OCTOBER 2023
CITY OF THOUSAND OAKS
Local Limits Report
PREPARED BY:
PREPARED FOR :
ATTACHMENT #3
DPW:610-10; 530-25;290-50\ev\Council\2025\070825\Sewer Use and Discharge Local Limits Ordinance Updates Att 3.pdf CITY OF THOUSAND OAKS October 2023 | i
HILL CANYON TREATMENT PLANT LOCAL LIMITS REPORT
TABLE OF CONTENTS
Section Page
INTRODUCTION ................................................................................................................................. 1 DESCRIPTION OF THE HILL CANYON TREATMENT PLANT................................................................. 2 LOCAL LIMITS DEVELOPMENT APPROACH ....................................................................................... 3 Pollutants of Concern .................................................................................................................... 3 Local Limits Monitoring ................................................................................................................. 4 Local Limits Data Review ........................................................................................................... 5 Additional Pollutant of Concern Screening ............................................................................... 6 Data Analysis ............................................................................................................................. 6 MAXIMUM ALLOWABLE HEADWORKS LOADINGS ........................................................................... 8 Environmental and Operational Restrictions Driving MAHL Derivation ....................................... 8 NPDES Permit Effluent Limitations ............................................................................................ 8 Biosolids Restrictions ................................................................................................................. 8 Treatment Process Inhibition .................................................................................................... 8 HCTP Design Capacity ................................................................................................................ 9 Flow Measurements ...................................................................................................................... 9 Removal Efficiency Calculations .................................................................................................... 9 Allowable Headworks Loading Calculations................................................................................ 10 NPDES Permit Effluent Limitations .......................................................................................... 10 HCTP Treatment Design Capacity ............................................................................................ 11 Biological Treatment Process Inhibition .................................................................................. 11 Anaerobic Sludge Digestion Inhibition .................................................................................... 11 Biosolids Restrictions ............................................................................................................... 12 Maximum Allowable Headworks Loading ................................................................................... 13 Comparison of Current Influent Loads to MAHLs ....................................................................... 15 MAXIMUM ALLOWABLE INDUSTRIAL LOADINGS ........................................................................... 18 CITY OF THOUSAND OAKS October 2023 | ii
HILL CANYON TREATMENT PLANT LOCAL LIMITS REPORT
MAIL Calculation Procedures ...................................................................................................... 18 Derivation Results ....................................................................................................................... 18 MAIL Calculation Results ......................................................................................................... 18 Collection System-Based Limits ............................................................................................... 21 MAIL Allocation Methods ............................................................................................................ 22 Uniform Local Limits ................................................................................................................ 22 Local Limits by Contributory Flow ........................................................................................... 23 Facility-Specific Local Limits by Mass Proportion .................................................................... 23 Creative Allocation .................................................................................................................. 23 MAIL Allocation ........................................................................................................................... 23 PUBLIC PARTICIPATION ................................................................................................................... 26 NEXT STEPS ..................................................................................................................................... 27 REFERENCES .................................................................................................................................... 28
LIST OF TABLES
Table 1. Hill Canyon Treatment Plant Pollutants of Concern ........................................................................ 4 Table 2. Pollutants of Concern Screening ..................................................................................................... 7 Table 3. Hill Canyon Treatment Plant Maximum Allowable Headworks Loadings ...................................... 14 Table 4. Comparison of July 2019 to June 2022 Hill Canyon Treatment Plant Influent Loads to the Maximum Allowable Headworks Loadings ......................................................................................... 16 Table 5. Comparison of July 2019 to June 2022 Hill Canyon Treatment Plant Maximum Monthly Average Influent Loads for Ammonia, BOD, and TSS to the Maximum Allowable Headworks Loadings ......... 17 Table 6. Industrial User Average Daily Chloride Load ................................................................................. 19 Table 7. Hill Canyon Treatment Plant Maximum Allowable Industrial Loadings ......................................... 20 Table 8. Hill Canyon Treatment Plant Proposed Uniform Local Limits ........................................................ 24 Table 9. Local Limits Monitoring Program – Recommended On-going Monitoring Frequency................... 27
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LIST OF ACRONYMS
AHL Allowable headworks loading
BNR Biological nutrient removal
BOD Biochemical oxygen demand
CCR California Code of Regulations
CFR Code of Federal Regulations
DNQ Detected but not quantified
HCTP Hill Canyon Treatment Plant
MAHL Maximum allowable headworks loading
MAIL Maximum allowable industrial loading
MBAS Methylene blue active substances
MDL Method detection limit
MGD million gallons per day
MLE Modified Ludzak-Ettinger
NIOSH National Institute for Occupational Safety and Health NPDES National Pollutant Discharge Elimination System
PCB Polychlorinated biphenyl
POC Pollutant of concern
POTW Publicly-owned treatment works
QA/QC Quality assurance/quality control
RL Reporting limit
ROS Regression-on-order statistics
TDS Total dissolved solids
TSS Total suspended solids
TTO Total toxic organics
USEPA United States Environmental Protection Agency
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INTRODUCTION
The City of Thousand Oaks (City) is required to implement a Pretreatment Program under Title 40 of the Code of Federal Regulations (40 CFR) Part 403 and its National Pollutant Discharge Elimination System (NPDES) permit (Order No. R4-2019-0137), which was adopted by the Los Angeles Regional Water Quality Control Board (Los Angeles Water Board) in November 2019.
Local limits development and implementation are part of the City’s Pretreatment Program, which involves strategies to control discharge of conventional and toxic pollutants entering the Hill Canyon Treatment Plant (HCTP) from permitted dischargers (e.g., industrial users). The objectives of the City’s Pretreatment Program are to prevent:
• Interference and/or upset with HCTP treatment operations • Pass-through of conventional and toxic pollutants
• Harm to the HCTP and/or collection system infrastructure • Contamination of municipal biosolids
• Worker exposure to chemical hazards
The City’s local limits were developed prior to 1994. The City conducted local limits evaluations and proposed updates in 1994 and 2004, but the proposed local limit updates were implemented. Due to the changes that have occurred in regulations and HCTP upgrades since the adoption and implementation of the current local limits, the purpose of this report is to present updated local limits to protect the HCTP treatment processes and infrastructure, meet current NPDES permit effluent limitations, protect biosolids quality, and protect worker health and safety. The major elements of this report include the following:
• Description of the Hill Canyon Treatment Plant
• Local limits development approach
• Maximum allowable headworks loadings
• Maximum allowable industrial loadings
• Public participation
• Next steps
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DESCRIPTION OF THE HILL CANYON TREATMENT PLANT
The City of Thousand Oaks owns and operates the Hill Canyon Treatment Plant, which treats domestic, commercial, and industrial wastewater. The HCTP has a dry weather design capacity of 14 million gallons per day (mgd) and serves an estimated population of 130,000 people.
Wastewater treatment at the HCTP includes preliminary treatment through a rock baffle and step-stair screens followed by aerated grit removal. The HCTP has three rectangular primary clarifiers in the South Plant and four circular primary clarifiers in the North Plant where wastewater undergoes primary sedimentation. Secondary treatment is accomplished via nitrification and denitrification for biological nitrogen removal (BNR) using the Modified Ludzack-Ettinger (MLE) process. There are two aeration basins in the North Plant and four in the South Plant, and three secondary clarifiers. Secondary effluent is filtered through ten deep bed, multi-media filters, and then disinfected using sodium hypochlorite and aqueous ammonia in a closed chlorine contact chamber. After chlorination, treated wastewater is dechlorinated with sodium bisulfite before it is discharged to the North Fork of Arroyo Conejo.
The HCTP biosolids stabilization process consists of combining primary sludge from the primary clarifiers and waste activated sludge from the secondary clarifiers through a common solid handling process that includes thickening, anaerobic digestion, dewatering, and drying. Grit and screenings are hauled off-site for disposal in a landfill. Biosolids are hauled to an off-site facility for composting.
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LOCAL LIMITS DEVELOPMENT APPROACH
The procedures for deriving local limits are described in the United States Environmental Protection Agency (USEPA) Local Limits Development Guidance, 2004 (Local Limits Guidance), which include the following steps:
• Identifying pollutants of concern (POCs)
• Collecting sufficient monitoring data
• Deriving the maximum allowable headworks loading (MAHL) • Calculating the maximum allowable industrial loading (MAIL) • Developing the allocation method for permitted dischargers Identifying pollutants of concern and local limits monitoring are addressed in this section of the report. The other steps are discussed in the following sections.
POLLUTANTS OF CONCERN
The first step in local limits development involves identifying POCs that may prevent the City’s Pretreatment Program from achieving its objectives. Local Limits Guidance identifies 15 national POCs that are commonly found in publicly-owned treatment works (POTW) influent, effluent, and biosolids. These national POCs are arsenic, cadmium, chromium, copper, cyanide, lead, nickel, silver, mercury, molybdenum, selenium, zinc, biochemical oxygen demand (BOD), total suspended solids (TSS), and ammonia (as N). The national POCs and HCTP-specific POCs were evaluated and summarized in the Local Limits Evaluation (April 2020) and included in Appendix A. Based on the Local Limits Evaluation, a summary of the POCs considered for this study are presented in Table 1.
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Table 1. Hill Canyon Treatment Plant Pollutants of Concern Conventional
Ammonia as N Sulfide as S
Biochemical oxygen demand (BOD) Total dissolved solids (TDS) Chloride Total suspended solids (TSS)
Sulfate as SO4
Metals
Arsenic Mercury
Barium Molybdenum
Boron Nickel
Cadmium Selenium
Chromium Silver
Cobalt Vanadium
Copper Zinc
Lead
Organics Bis(2-ethylhexyl)phthalate
Other Toxics Cyanide
As discussed in the following section, local limits monitoring was conducted to obtain data necessary to update or develop local limits for these pollutants.
LOCAL LIMITS MONITORING
It is necessary to collect and analyze water quality data in order to develop a technically-sound and supportable strategy to control POCs entering into and within the HCTP. Three general areas that are monitored for local limits development include the following:
• Collection system
• Wastewater treatment plant
• Biosolids
First, it is important to determine the distribution of controllable and non-controllable pollutant sources. Uncontrollable pollutant sources (non-industrial users such as residential, commercial, inflow and infiltration, drinking water, and stormwater) typically contribute most of the wastewater flow to a POTW, but generally contain lower concentrations when compared to industrial wastewater, which are controllable sources. The City conducted pollutant sampling at
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one collection system site, which services residential and commercial users and no industrial users, to obtain the necessary data to characterize pollutant levels from uncontrollable sources.
Second, in-plant removal efficiencies are required to calculate the maximum pollutant loads that can be accepted at the headworks and effectively treated without overloading HCTP design treatment capacities, upsetting treatment processes, or exceeding effluent water or biosolids quality limitations. This information was developed by collecting influent, primary treatment effluent, final effluent water quality and anaerobic sludge digester data to calculate appropriate in-plant removal efficiencies.
Finally, biosolids quality must be assessed because biosolids disposal regulations require different levels of biosolids quality depending on disposal practices. Biosolids must be monitored to determine the presence of any POCs and to derive local limits that will protect biosolids handling processes and quality. Biosolids quality data were not collected as part of the Local Limits Monitoring Program. Instead, existing data collected for HCTP’s Biosolids Annual Reports from 2019 to 2021 were utilized in this assessment.
The Local Limits Evaluation identified several data gaps and recommended additional monitoring to further assess potential POCs and to gather data at the necessary locations for the local limits update. The Local Limits Sampling Plan (May 2022), included in Appendix B, provides detailed information about the City’s Local Limits Monitoring Program. Data collected in May and June 2022 during local limits monitoring were supplemented with relevant monitoring data collected between July 2019 and June 2022 by the City as part of its on-going monitoring program and requirements.
Local Limits Data Review
All local limits monitoring sample analyses were conducted by Weck Laboratories, Inc.
Laboratory reports included analytical results, reporting limits (RLs), and method detection limits (MDLs) along with all laboratory quality assurance/quality control (QA/QC) results. Results below the RL, but above the MDL were qualified as detected but not quantified (DNQ), or “J-flagged”.
Results below the MDL were qualified as “non-detect”. Although they were estimated, all monitoring results qualified as “J-flagged” were included in local limits derivation calculations. A summary of analytical results is presented in Appendix D. Original analytical laboratory reports are available upon request.
QA/QC analyses were conducted to ensure analytical data quality. For the Local Limits Monitoring Program, the following QA/QC analyses were initiated:
• Field controls (field log, clean sampling and handling techniques, field blanks, equipment blanks, field duplicates)
• Laboratory controls (laboratory duplicates, standard laboratory calibration procedures, matrix spikes/matrix spike duplicates, laboratory control standards, method blanks) • Sample chain-of-custody
• Data verification
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There were QA/QC issues with the collection system equipment blank sampling, composite samples likely collecting excess sediment from the collection system, and analysis for chromium during the local limits monitoring. These issues are is discussed in Appendix F.
Additional Pollutant of Concern Screening
Additional screening of POCs was conducted using a step included in USEPA’s Guidance Manual on the Development and Implementation of Local Discharge Limitations under the Pretreatment Program (December 1987) (1987 Local Limits Guidance) to determine if the pollutants needed to undergo a headworks loading analysis or local limit development. The screening step criteria used are as follows:
• Criterion 1. The maximum concentration of the pollutant in the effluent is more than one-half the allowable effluent concentration required to meet water quality criteria/standards or the maximum sludge concentration is more than one-half the applicable biosolids criteria guidelines; or
• Criterion 2. The maximum concentration of the pollutant in a grab sample from the influent is more than one-half the inhibition threshold; or • Criterion 3. The maximum concentration of the pollutant in a composite sample from the influent is more than one-fourth the inhibition threshold; or • Criterion 4. The maximum concentration of the pollutant in the influent is more than 1/500th of the applicable biosolids use criteria.
Pollutants that did not meet the screening criteria above did not undergo further headworks loading analysis or local limits development because they were detected at levels significantly below any applicable environmental and/or operational restrictions or limits. This analysis was initially conducted in the Local Limits Evaluation. However, there were several pollutants for which there were insufficient data to conduct the screening. The City collected additional data during the Local Limits Monitoring Program so these pollutants could be screened. A summary of the screening for these pollutants with additional data is presented in Table 2.
Based on this screening, local limits will be developed for the pollutants in Table 1 and exclude those in Table 2.
Data Analysis
When possible, data are statistically analyzed using regression-on-order statistics (ROS), which is a method that determines summary statistics for data sets that have non-detect data. The ROS method develops probability plotting positions for each data point (detect and non-detect values) based on an ordering of the data. The log-transform of the data is regressed and fitted with a least squares line to probability plotting positions. Non-detect data points are assigned values for calculation of summary statistics based on their probability plotting positions and the regression line equation. Summary statistics are calculated based on the detected data points and “filled-in” non-detect values. Variance summary statistics are calculated using a Tukey- Jackknife algorithm, which sequentially removes one point from the dataset, runs the analysis, and calculates the variance estimators as the average of each of the “n” runs of data.
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Table 2. Pollutants of Concern Screening
Pollutant Screening Result
Sulfide as S The maximum influent concentration (0.7 mg/L) is less than one-half of the activated sludge level (25 mg/L). A local limit will not be developed for this pollutant at this time.
Barium The maximum influent concentration (0.069 mg/L) is less than one-half of the CCR Biosolids Regulations inhibition criteria (10 mg/L). A local limit will not be developed for this pollutant at this time.
Boron The existing local limit for boron will be retained at 1 mg/L.
Cobalt The maximum influent concentration (0.41 ug/L) is less than one-half of the CCR Biosolids Regulations inhibition criteria (8,000 ug/L). A local limit will not be developed for this pollutant at this time.
Vanadium The maximum influent concentration (6.4 ug/L) is less than one-half of the CCR Biosolids Regulations inhibition criteria (2,400 ug/L). A local limit will not be developed for this pollutant at this time.
Bis(2-ethylhexyl)
phthalate
The effluent concentrations are all non-detect below one-half of the effluent limit. A local limit will not be developed for this pollutant at this time.
ROS is limited if there are insufficient data (e.g., less than 20 percent detected data, too few data points) to perform the analysis. This approach is generally found to provide only small errors for major summary statistics parameters (mean, median, standard deviation, and interquartile range) when less than 100 percent of the data are detected. It should be noted that unless all data are detected, the ROS method is only an estimation of the data.
In cases where the ROS method could not be used, a surrogate is used to substitute for non- detect results. The three surrogates commonly used (per the 2004 Local Limits Guidance) are the reporting limit, zero, and one-half the reporting limit. The most conservative approach is to select a surrogate equal to the reporting limit, which assumes that the pollutant concentration is always higher than the actual value. On the other hand, if the surrogate is equal to zero, it assumes that the pollutant concentration is likely lower than the actual value. For this derivation of local limits, the MDL is used for non-detect data when there were insufficient detected data to use the ROS method.
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MAXIMUM ALLOWABLE HEADWORKS LOADINGS
The MAHL is the maximum pollutant loading that may be received at the HCTP headworks and not have the potential to negatively impact the City’s Pretreatment Program objectives. The MAHL must be determined for each POC before developing a local limit. In this section, the following information is presented:
• Environmental and operational restrictions driving MAHL derivation • Flow measurements
• Removal efficiency calculations
• Allowable headworks loading calculations
• Maximum allowable headworks loading
• Need for local limit
ENVIRONMENTAL AND OPERATIONAL RESTRICTIONS DRIVING MAHL
DERIVATION
Four major factors serve as the basis for MAHL development. These include NPDES permit effluent limitations, biosolids disposal restrictions, treatment process inhibition levels, and HCTP treatment design capacity. These restrictions are described in this section.
NPDES Permit Effluent Limitations
The City’s NPDES permit provides numeric restrictions on effluent discharges ammonia as N, BOD, boron, chloride, methylene blue active substances (MBAS), nitrate plus nitrite as N, nitrate as N, nitrite as N, oil and grease, sulfate, TDS, TSS, copper, nickel, mercury, cyanide, bis(2- ethylhexyl)phthalate, chlorpyrifos, diazinon, chlordane, 4,4’-DDD, 4,4’-DDE, 4,4’-DDT, dieldrin, polychlorinated biphenyls (PCBs), and toxaphene. The City’s NPDES permit restrictions are presented in Appendix C of this report. As previously discussed, several pollutants with NPDES permit effluent limitations were removed from consideration for local limit update or development in the Local Limits Evaluation.
Biosolids Restrictions
The City currently disposes of biosolids at a composting facility. Restrictions for metals under 40 CFR Part 503 apply for biosolids disposed of through land application or composting. Waste disposal, which includes biosolids, is also subject to hazardous waste requirements for metals, pesticides, and polychlorinated biphenyls (PCBs) under Title 22 of the California Code of Regulations (CCR). The biosolids disposal restrictions used in the development of MAHLs are presented in Appendix C of this report. As previously discussed, several pollutants with biosolids restrictions were removed from consideration for local limit update or development in the Local Limits Evaluation.
Treatment Process Inhibition
Treatment process inhibition refers to pollutant levels that will interfere with biological, chemical, and/or physical processes of wastewater treatment, thereby resulting in reduced
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facility performance and/or upset. To protect the HCTP, the activated sludge, nitrification, and anaerobic sludge digestion inhibition levels from the 2004 Local Limits Guidance, which are presented in Appendix C, were used for this analysis. As previously discussed, several pollutants that may cause treatment process inhibition were removed from consideration for local limit update or development in the Local Limits Evaluation.
HCTP Design Capacity
For ammonia as N, BOD, and TSS, it is necessary to consider the design capacity of the HCTP in formulating the MAHLs. For this analysis, the maximum monthly design capacity for BOD and TSS were 27,000 and 29,000 lbs/day, respectively, at the current ratio of the influent flow rate to the annual average design flow. There is no design capacity loading for ammonia.
FLOW MEASUREMENTS
Flow measurements are used to calculate pollutant mass loadings. The following flow information is necessary to calculate pollutant loadings:
• Influent and effluent flow
• Industrial user flow
• Biosolids volume for disposal
The July 2019 to June 2022 average daily influent and effluent flows were 8.67 mgd and 8.55 mgd, respectively. When calculating pollutant loads, average daily flow data corresponding to the sample date was used. The 2022 average industrial flow was estimated to be 0.77 mgd based on data available to the City. From the 2019 to 2021 Sludge Handling and Disposal Activities, the average daily mass of biosolids disposed of at the landfill was 11,200 pounds per day dry weight with an average of 63.5 percent solids.
REMOVAL EFFICIENCY CALCULATIONS
Removal efficiency through the HCTP, or specific unit within the treatment process, is defined as the fraction (or percent) of the pollutant that is removed. The 2004 Local Limits Guidance identifies several methods of calculating removal efficiencies, including the average daily removal efficiency, mean removal efficiency, and decile methods. For this study, removal efficiencies were calculated using the mean removal efficiency method and utilized historical monitoring data. The mean removal efficiency method allows for the use of historical data that may not have been collected based on the hydraulic residence time.
The primary treatment removal efficiency according to the mean removal efficiency method is calculated using the following equation:
𝑅𝑅
𝑃𝑃 = 𝐶𝐶𝐼𝐼𝐼𝐼 − 𝐶𝐶𝑃𝑃𝑃𝑃
𝐶𝐶𝐼𝐼𝐼𝐼
× 100%
Where:
RP Pollutant removal efficiency through primary treatment process
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CIN Average influent pollutant concentration
CPE Average primary treatment effluent pollutant concentration Total HCTP removal efficiencies were calculated as a change in loads as opposed to change in concentrations to account for the difference in influent and final effluent flows. The total removal efficiency was calculated using the following equation:
𝑅𝑅𝐻𝐻𝐻𝐻𝐻𝐻𝑃𝑃 = 𝐿𝐿𝐼𝐼𝐼𝐼 − 𝐿𝐿𝐹𝐹𝑃𝑃
𝐿𝐿𝐼𝐼𝐼𝐼
× 100%
Where:
RHCTP Pollutant removal efficiency through the HCTP
LIN Average influent pollutant load [lb/day]
LFE Average final effluent pollutant load [lb/day]
In general, the following guidelines are used when calculating removal efficiencies:
• Calculated removal efficiencies were cross-checked with removal efficiency ranges provided in the Local Limits Guidance to verify that realistic values are used. • Special consideration was given to instances when the concentrations of pollutants appear to increase during the treatment process. In these situations, negative removal efficiencies were used to derive local limits. This approach provides a conservative assessment of treatment performance as well as an additional safety factor to protect the HCTP. Negative removal efficiencies may result from chemical addition of the pollutant during treatment or generation of the pollutant during treatment. • For instances where the influent data was detected but effluent data was non-detected, the minimum reporting limits were utilized as surrogates to calculate the removal efficiencies.
• Literature removal efficiencies were used for instances where insufficient sampling results or insufficient detected data were identified (See Appendix F).
ALLOWABLE HEADWORKS LOADING CALCULATIONS
Prior to developing a local limit, it is necessary to calculate allowable headworks loading (AHLs) for each POC for each operational restriction or environmental criterion. The AHL is the estimated pollutant loading that can be received at the headworks without causing an exceedance of a particular operational restriction or environmental criterion. AHLs are calculated for each type of restriction (i.e., NPDES permit effluent limitations, treatment design capacity, treatment process inhibition levels, biosolids disposal restrictions). The calculation procedures shown below are based on the methodologies and equations in the 2004 Local Limits Guidance. Depending on the units used, conversion factors are applied to the calculations.
NPDES Permit Effluent Limitations
The AHL based on NPDES permit effluent limitations was calculated using the following equation to prevent pass-through:
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𝐴𝐴𝐴𝐴𝐿𝐿𝐼𝐼𝑃𝑃𝑁𝑁𝑃𝑃𝑁𝑁 = 8.34 × 𝐶𝐶𝐼𝐼𝑃𝑃𝑁𝑁𝑃𝑃𝑁𝑁 × 𝑄𝑄𝐹𝐹𝑃𝑃
1 − 𝑅𝑅𝐻𝐻𝐻𝐻𝐻𝐻𝑃𝑃
Where:
AHLNPDES NPDES permit-based AHL [lbs/day]
CNPDES NPDES permit effluent limitation [mg/L]
QFE Average daily final effluent flow rate [mgd]
RHCTP Pollutant removal efficiency through the HCTP
HCTP Treatment Design Capacity
The HCTP treatment design capacities for BOD and TSS, as discussed above, were directly used as the AHL.
Biological Treatment Process Inhibition
The AHL based on activated sludge inhibition was calculated using the following equation:
𝐴𝐴𝐴𝐴𝐿𝐿𝐴𝐴𝑁𝑁 = 8.34 × 𝐶𝐶𝐴𝐴𝑁𝑁 × 𝑄𝑄𝐼𝐼𝐼𝐼
1 − 𝑅𝑅𝑃𝑃
Where:
AHLAS Activated sludge inhibition-based AHL [lbs/day]
CAS Activated sludge inhibition concentration [mg/L]
QIN Average daily final influent flow rate [mgd]
RP Pollutant removal efficiency through primary treatment The AHL based on nitrification inhibition was calculated using the following equation:
𝐴𝐴𝐴𝐴𝐿𝐿𝐼𝐼 = 8.34 × 𝐶𝐶𝐼𝐼 × 𝑄𝑄𝐼𝐼𝐼𝐼
1 − 𝑅𝑅𝑃𝑃
Where:
AHLN Nitrification inhibition-based AHL [lbs/day]
CN Nitrification inhibition concentration [mg/L]
QIN Average daily final influent flow rate [mgd]
RP Pollutant removal efficiency through primary treatment Anaerobic Sludge Digestion Inhibition
The AHL for anaerobic sludge digestion inhibition depends on whether a pollutant is conservative (e.g., metals) or non-conservative (e.g., cyanide). For conservative pollutants, the AHL based on anaerobic sludge digestion inhibition is calculated using the following equation:
𝐴𝐴𝐴𝐴𝐿𝐿
𝐴𝐴𝑁𝑁𝑁𝑁 = 8.34 × 𝐶𝐶𝐴𝐴𝑁𝑁𝑁𝑁 × 𝑄𝑄𝐴𝐴𝑁𝑁𝑁𝑁
𝑅𝑅𝐻𝐻𝐻𝐻𝐻𝐻𝑃𝑃
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Where:
AHLASD Anaerobic sludge digestion inhibition-based AHL for conservative pollutants [lbs/day]
CASD Anaerobic sludge digestion inhibition concentration [mg/L] QASD Average daily flow to anaerobic sludge digesters [mgd] RHCTP Pollutant removal efficiency through the HCTP
For non-conservative pollutants, the AHL based on anaerobic sludge digestion is calculated using the following equation:
𝐴𝐴𝐴𝐴𝐿𝐿𝐴𝐴𝑁𝑁𝑁𝑁 = 8.34 × 𝐿𝐿𝐼𝐼𝐼𝐼 × 𝐶𝐶𝐴𝐴𝑁𝑁𝑁𝑁
𝐶𝐶𝑁𝑁𝐼𝐼𝐷𝐷
Where:
AHLASD Anaerobic sludge digestion inhibition-based AHL for non-conservative pollutants [lbs/day]
LIN Average influent pollutant load [lbs/day]
CASD Anaerobic sludge digestion inhibition concentration [mg/L] CDIG Average anaerobic sludge digester pollutant concentration [mg/L] Biosolids Restrictions
Biosolids generated by the HCTP are disposed of through composting, which means that both 40 CFR Part 503 and CCR Title 22 biosolids restrictions apply.
The AHL based on 40 CFR Part 503 biosolids restriction is calculated using the following equation:
𝐴𝐴𝐴𝐴𝐿𝐿𝐻𝐻𝐹𝐹𝐶𝐶 = 0.000001 × 𝐶𝐶𝐻𝐻𝐹𝐹𝐶𝐶 × 𝑉𝑉𝐵𝐵𝐼𝐼𝐵𝐵𝑁𝑁𝐵𝐵𝐵𝐵𝐼𝐼𝑁𝑁𝑁𝑁 𝑅𝑅𝐻𝐻𝐻𝐻𝐻𝐻𝑃𝑃
Where:
AHLCFR 40 CFR Part 503 biosolids restriction-based AHL [lbs/day] CCFR 40 CFR Part 503 numeric biosolids restrictions [mg/kg dry weight] VBIOSOLIDS Average daily volume of biosolids disposed of [lbs/day dry weight] RHCTP Pollutant removal efficiency through the HCTP
Biosolids cannot be hazardous waste if they are to be disposed of in non-hazardous waste facilities (e.g., composted, land applied). CCR Title 22 biosolids restrictions may apply either to conservative or non-conservative pollutants. However, non-conservative pollutants were evaluated and excluded from this study during the Local Limits Evaluation. For conservative pollutants, the AHL based on CCR biosolids restriction is calculated using the following equation:
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𝐴𝐴𝐴𝐴𝐿𝐿𝐻𝐻𝐻𝐻𝐶𝐶 = 0.000001 × 𝐶𝐶𝐻𝐻𝐻𝐻𝐶𝐶 × 𝑉𝑉𝐵𝐵𝐼𝐼𝐵𝐵𝑁𝑁 𝐵𝐵𝐵𝐵𝐼𝐼 𝑁𝑁𝑁𝑁 𝑃𝑃𝑃𝑃 × 𝑅𝑅𝐻𝐻𝐻𝐻𝐻𝐻𝑃𝑃
Where:
AHLCCR CCR Title 22 biosolids restrictions-based AHL [lbs/day] CCCR CCR Title 22 numeric biosolids restrictions [mg/kg wet weight] VBIOSOLIDS Average daily volume of biosolids disposed of [lbs/day dry weight] PS Percent solids at disposal
RHCTP Pollutant removal efficiency through the HCTP
MAXIMUM ALLOWABLE HEADWORKS LOADING
Following the calculation of the applicable AHLs for each POC, the minimum AHL for each POC is designated as the MAHL, or the maximum influent loading that can be accepted at the HCTP headworks to ensure compliance with all operational restrictions and/or environmental criteria.
The MAHLs are presented in Table 3.
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Table 3. Hill Canyon Treatment Plant Maximum Allowable Headworks Loadings Pollutant MAHL
(lbs/day) (1) Basis for MAHL
Conventional
Ammonia as N 7,600 Anaerobic digestion inhibition
Biochemical oxygen demand (BOD) 27,000 HCTP design capacity Chloride 9,600 NPDES permit effluent limitation
Sulfate as SO4 15,000 NPDES permit effluent limitation
Total dissolved solids (TDS) 61,000 NPDES permit effluent limitation Total suspended solids (TSS) 29,000 HCTP design capacity Metals (total recoverable)
Arsenic 1.4 40 CFR Part 503 biosolids restrictions
Cadmium 0.55 40 CFR Part 503 biosolids restrictions
Chromium 11 CCR Title 22 biosolids restrictions
Copper 5.4 NPDES permit effluent limitation
Lead 3.6 40 CFR Part 503 biosolids restrictions
Mercury 0.045 NPDES permit effluent limitation
Molybdenum 5.5 40 CFR Part 503 biosolids restrictions
Nickel 14 NPDES permit effluent limitation
Selenium 2.1 40 CFR Part 503 biosolids restrictions
Silver 7.2 Anaerobic digestion inhibition
Zinc 11 Nitrification inhibition
Other Toxics
Cyanide 0.89 NPDES permit effluent limitation
(1) Based on average influent and effluent flow rates of 8.67 mgd and 8.55 mgd, respectively (July 2019 - June 2022).
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COMPARISON OF CURRENT INFLUENT LOADS TO MAHLS
Although MAHLs were calculated for each POC, there may not be a need to develop a local limit for the pollutant. The following 2004 Local Limits Guidance evaluation and exclusion steps are intended to determine if local limits are necessary for each POC. A local limit is not necessary if the following criteria are met:
• The average influent loading of the pollutant is less than 60 percent of the MAHL; • The maximum daily influent loading of the pollutant is less than 80 percent of the MAHL any time in the 12-month period preceding the analysis; or • Monthly average influent loading is less than 80 percent of the average design capacity for BOD, TSS, and ammonia as N during any one month in the 12-month period preceding the analysis.
A comparison of the MAHLs with the July 2019 to June 2022 average and maximum influent loadings, for each POC, except ammonia as N, BOD, and TSS, is presented in Table 4.
For ammonia as N, BOD, and TSS, the 2004 Local Limits Guidance recommends using a monthly average comparison of influent loading to the MAHL because POTWs are expected to have capacity to consistently treat a design conventional pollutant load to acceptable levels for discharge. The July 2019 to June 2022 maximum monthly average influent loads, for ammonia as N, BOD, and TSS and percentages of the respective MAHLs are presented in Table 5.
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Table 4. Comparison of July 2019 to June 2022 Hill Canyon Treatment Plant Influent Loads to the Maximum Allowable Headworks Loadings
Pollutant MAHL
(lbs/day) (1)
Average
Influent
Load
(lbs/day)
Average
Influent %
of MAHL (2)
Maximum
Influent
Load
(lbs/day)
Maximum
Influent %
of MAHL (3)
Conventional
Chloride 9,600 8,800 92% 9,900 103%
Sulfate as SO4 15,000 7,700 51% 12,000 80%
Total dissolved solids (TDS) 61,000 42,000 69% 55,000 90% Metals (total recoverable)
Arsenic 1.4 0.33 24% 0.43 31%
Cadmium 0.55 0.012 2.2% 0.036 6.5%
Chromium 11 0.12 1.1% 0.23 2.1%
Copper 5.4 2.9 54% 3.8 70%
Lead 3.6 0.075 2.1% 0.17 4.7%
Mercury 0.045 0.0039 8.7% 0.012 27%
Molybdenum 5.5 1.4 25% 2.2 40%
Nickel 14 0.22 1.6% 0.35 2.5%
Selenium 2.1 0.078 3.7% 0.13 6.2%
Silver 7.2 0.016 0.22% 0.024 0.33%
Zinc 11 9.9 90% 14 130%
Other Toxics
Cyanide 0.89 0.12 13% 0.13 15%
(1) Based on average influent and effluent flow rates of 8.67 mgd and 8.55 mgd, respectively (July 2019 - June 2022).
(2) Percentages in bold indicate average influent load exceeds 60 percent of the MAHL. (3) Percentages in bold indicate maximum influent load exceeds 80 percent of the MAHL.
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Table 5. Comparison of July 2019 to June 2022 Hill Canyon Treatment Plant Maximum Monthly Average Influent Loads for Ammonia, BOD, and TSS to the Maximum Allowable Headworks Loadings
Pollutant MAHL
(lbs/day) (1)
Maximum
Monthly Average
Influent Load
(lbs/day)
Maximum
Monthly Average
Influent % of
MAHL (2)
Ammonia as N 7,600 4,200 55%
Biochemical oxygen demand (BOD) 27,000 26,000 96%
Total suspended solids (TSS) 29,000 30,000 103%
(1) Based on average influent and effluent flow rates of 8.67 mgd and 8.55 mgd, respectively (July 2019 - June 2022).
(2) Percentages in bold indicate maximum influent load exceeds 80 percent of the MAHL.
Of the pollutants that were evaluated through the headworks loading analysis, BOD, chloride, sulfate as SO4, TDS, TSS, and zinc were above the threshold requiring the development of local limits. Additionally, it is recommended that local limits be updated for other national POCs, including ammonia as N, arsenic, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, silver, and cyanide because these pollutants are commonly found in industrial wastewater.
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MAXIMUM ALLOWABLE INDUSTRIAL LOADINGS
From the MAHL, the MAIL and subsequent local limits are derived. The MAIL is the maximum pollutant loading from industrial users that may enter the HCTP without resulting in an exceedance of the MAHLs. In this section, the following information is presented:
• MAIL calculation procedures
• Derivation results
• MAIL allocation methods
MAIL CALCULATION PROCEDURES
The MAIL, or the maximum pollutant load that can come from industrial sources, is obtained from the MAHL by reducing the MAHL by a safety factor and subtracting the existing loading from uncontrollable sources (i.e., non-permitted sources). The MAIL is calculated using the following equation:
𝑀𝑀𝐴𝐴𝑀𝑀𝐿𝐿 = (1 − 𝑃𝑃𝑆𝑆) × 𝑀𝑀𝐴𝐴𝐴𝐴𝐿𝐿 − (8.34 × 𝑄𝑄𝑈𝑈 × 𝐶𝐶𝑈𝑈) Where:
MAIL Maximum allowable industrial loading for pollutant [lbs/day] SF Safety factor
MAHL Maximum allowable headworks loading [lbs/day]
QU Average daily flow rate from uncontrolled sources [mgd] CU Average pollutant concentration from uncontrolled sources [mg/L] As indicated in the equation above, the 2004 Local Limits Guidance suggests reserving a portion of the MAIL as a safety factor to account for variability in data, quality of data used in MAHL and MAIL derivations, and potential for slug loadings. The 2004 Local Limits Guidance also states that “as a general rule, a minimum safety factor of 10% of the maximum allowable headworks loading is usually necessary to adequately address [these] issues.” Unless otherwise noted, a safety factor of 10 percent is used in the development of MAILs presented below.
DERIVATION RESULTS
The following section provides the results of MAIL derivation and collection system-based numeric limits.
MAIL Calculation Results
For this analysis, MAILs were derived using a spreadsheet model based upon the methodologies provided in the 2004 Local Limits Guidance for each pollutant.
Additional consideration was taken for the development of the MAIL for chloride. The average chloride concentration at the collection system location from local limits sampling was 160 mg/L, which resulted in a load of 10,500 lbs/day. This uncontrollable source load is significantly higher than the average influent load of 8,800 lbs/day. A review of historical industrial
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monitoring data indicated that these sources contribute approximately 700 lbs/day of chloride to HCTP. This results in a chloride load from uncontrollable sources of 8,100 lbs/day. This adjusted uncontrollable chloride load was used to calculate the MAIL. A summary of industrial user chloride loads is presented in Table 6.
A similar analysis could not be conducted for zinc because there was an incomplete data set from industrial users.
Table 6. Industrial User Average Daily Chloride Load
Industrial User
Average
Daily Flow
(mgd)
July 2021-June 2023
Average Chloride
Concentration (mg/L)
Average Daily
Chloride Load
(lbs/day)
Amgen 0.40 101 340
Baxalta 0.09 117 90
Skyworks (Hillcrest) 0.24 110 220
Skyworks (Lawrence) 0.02 90 10
Teledyne 0.02 106 20
Total 0.77 680
The MAIL derivations are summarized in Table 7 and presented in Appendix E. The assumptions used in the local limits derivations are summarized in Appendix F. These are the proposed local limits expressed as the MAIL in pounds per day (lbs/day).
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Table 7. Hill Canyon Treatment Plant Maximum Allowable Industrial Loadings Pollutant Maximum Allowable
Industrial Loading (lbs/day) (1)
Conventional
Ammonia as N 1,900
Biochemical oxygen demand (BOD) 3,200
Chloride 1,000
Sulfate as SO4 6,000
Total dissolved solids (TDS) 13,000
Total suspended solids (TSS) 3,200
Metals (total recoverable)
Arsenic 1.1
Cadmium 0.48
Chromium 10
Copper 2.1
Lead 3.2
Mercury 0.037
Molybdenum 4.6
Nickel 12
Selenium 1.8
Silver 6.5
Zinc (2)
Other Toxics
Cyanide 0.55
(1) Based on average influent and effluent flow rates of 8.67 mgd and 8.55 mgd, respectively (July 2019 - June 2022 average daily flow).
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(2) The maximum allowable industrial loading could not be calculated for this pollutant because the pollutant load from uncontrollable sources (e.g., non-industrial) exceeded the maximum allowable headworks loading.
Collection System-Based Limits
Collection system-based numeric limits, which are intended to address explosivity, corrosivity, flow obstruction, temperature, and headspace toxicity, apply directly to users and do not involve calculation of local limits.
The General Pretreatment Regulations (40 CFR Part 403.5(b)(1)) prohibit discharge of “pollutants that will cause a fire or explosion hazard in the collection system. The City prohibits these discharges in the City of Thousand Oaks Municipal Code. The City is currently in the process of updating its Municipal Code and this restriction will be included in Section 10-1.606(b)(1). A resource for closed cup flashpoint values is the National Institute for Occupational Safety and Health (NIOSH) chemical database (http:///www.cdc.gov/niosh/npg ).
The General Pretreatment Regulations (40 CFR Part 403.5(b)(2)) specify a minimum industrial discharge pH limit of 5.0 to prevent against corrosion. Federal regulations (40 CFR Part 261.22(a)(1)) also specify that the maximum discharge pH limit should be 12.5 to prevent wastewater from being classified as hazardous waste. The City implements a minimum discharge pH of 6.5 and a maximum discharge pH of 8.5 as established in Section 4.A.1.c of its NPDES permit. The City is currently in the process of updating its Municipal Code and this restriction will be included in Section 10-1.606(b)(2). The City is proposing to revise its minimum discharge pH to 6.0 and its maximum discharge pH to 11.5.
The General Pretreatment Regulations (40 CFR Part 403.5(b)(3)) prohibit discharge of solid or viscous pollutants that will obstruct flows and interfere with wastewater flows in the collection system or at the HCTP. The City prohibits these discharges in the City of Thousand Oaks Municipal Code. The City is currently in the process of updating its Municipal Code and this restriction will be included in Section 10-1.606(b)(3).
The General Pretreatment Regulations (40 CFR Part 403.5(b)(4)) prohibit the discharge of any pollutant, including oxygen demanding pollutants (e.g., BOD) released in a discharge at a flow rate and/or pollutant concentration which will cause interference in the collection system or at the HCTP. The City prohibits these discharges in the City of Thousand Oaks Municipal Code. The City is currently in the process of updating its Municipal Code and this restriction will be included in Section 10-1.606(b)(4).
The General Pretreatment Regulations (40 CFR Part 403.5(b)(5)) prohibit the discharge of heat in amounts which will inhibit biological activity at the HCTP resulting in interference. In no situation should heat be discharged in quantities such that the temperature at the HCTP exceeds 40°C (104°F). The City prohibits these discharges in the City of Thousand Oaks Municipal Code. The City is currently in the process of updating its Municipal Code and this restriction will be included in Section 10-1.606(b)(5).
The General Pretreatment Regulations (40 CFR Part 403.5(b)(6)) prohibit the discharge of petroleum oil, nonbiodegradable cutting oil, or products of mineral oil origin in amounts that will
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cause interference or pass through. The City prohibits these discharges in the City of Thousand Oaks Municipal Code. The City is currently in the process of updating its Municipal Code and this restriction will be included in Section 10-1.606(b)(6).
General Pretreatment Regulations (40 CFR Part 403.5(b)(7)) prohibit discharge of pollutants that can lead to the accumulation of toxic gases, vapors, or fumes in the collection system and/or at the HCTP in a quantity that may cause acute worker health and safety problems. T The City prohibits these discharges in the City of Thousand Oaks Municipal Code. The City is currently in the process of updating its Municipal Code and this restriction will be included in Section 10-
1.606(b)(7). A resource for fume toxicity screening levels is the NIOSH chemical database (http:///www.cdc.gov/niosh/npg
).
The General Pretreatment Regulations (40 CFR Part 403.5(b)(8)) prohibit the discharge of trucked or hauled pollutants except at discharge points designated by a POTW. The City, which allows trucked or hauled waste with approval by the Public Works Director, currently implements this requirement in the City of Thousand Oaks Municipal Code. The City is currently in the process of updating its Municipal Code and this restriction will be included in Sections 10-
1.606(b)(8) and 10-1.612.
MAIL ALLOCATION METHODS
MAIL allocation is necessary for developing local limits and permitting users under the Pretreatment Program. The 2004 Local Limits Guidance specifies the following four types of numeric local limits allocation strategies:
• Uniform local limits
• Local limits by contributory flow
• Facility-specific local limits by mass proportion
• Creative allocation
Uniform Local Limits
For certain parameters, it may be desirable to calculate uniform numeric discharge concentration restrictions that are intended to apply to all industrial users. This can be achieved by simply assigning the MAIL concentration as a local limit. In general, this is the most restrictive MAIL allocation approach, but the easiest to administer.
The MAIL can be converted to a uniform concentration using the following equation:
𝑀𝑀
𝐴𝐴𝑀𝑀𝐿𝐿𝐻𝐻𝐵𝐵𝐼𝐼𝐻𝐻 = 𝑀𝑀 𝐴𝐴𝑀𝑀𝐿𝐿
8.34 × 𝑄𝑄𝐼𝐼
Where:
MAILCONC MAIL expressed as a concentration [mg/L]
MAIL MAIL expressed as a load [lbs/day]
QI Average daily flow rate from all industrial users [mgd]
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Local Limits by Contributory Flow
The derivation of contributory flow local limits for targeted facilities is like the uniform local limits approach except that the number of users affected is limited to those for which it has been established that the given POC is present at levels higher than background levels. In other words, only dischargers that are known to or suspected of being significant contributors of the given pollutant would be subjected to the limit. For all remaining users, it is assumed that their discharges are non-industrial in character.
Contributory flow-based local limits are calculated from the MAIL as follows:
𝐿𝐿𝐿𝐿𝐻𝐻 = 𝑀𝑀𝐴𝐴𝑀𝑀𝐿𝐿 − 8.34 × 𝑄𝑄𝐵𝐵 × 𝐶𝐶𝐵𝐵
8.34 × (𝑄𝑄𝐵𝐵 + 𝑄𝑄𝑃𝑃𝐼𝐼)
Where:
LLC Contributory flow-based local limit [mg/L]
MAIL Maximum allowable industrial loading of pollutant [lbs/day] QPN Average total user daily flow rate for controlled sources not discharging pollutant [mgd]
QO Average daily flow rate for other users [mgd]
CO Average pollutant concentration for other users [mg/L] Facility-Specific Local Limits by Mass Proportion
Facility-specific local limits by mass proportion are developed by allocating the MAIL for each POC in proportion to the existing loadings from each user or at the discretion of the POTW. This approach enables dischargers with higher strength effluent to receive more achievable limits, while providing lower strength dischargers with limits more in line with the characteristics of their own discharges. The methodology for derivation of facility-specific local limits by mass proportion is presented in the 2004 Local Limits Guidance.
Creative Allocation
In general, after the MAIL has been calculated, a POTW has flexibility in allocating the loading among its permitted users as long as a safety factor is maintained and the POTW accounted for all allocations, and public notice of the allocation is properly issued and allocation is adopted.
MAIL ALLOCATION
The City proposes to adopt its local limits using the uniform local limits allocation method and implement them as daily maximum concentrations. The uniform local limits, which are based on the MAILs presented in Table 7, are presented in Table 8.
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Table 8. Hill Canyon Treatment Plant Proposed Uniform Local Limits Pollutant Existing Local Limit
(mg/L)
Proposed Local
Limit as Daily
Maximum
(mg/L) (1)
Conventional
Ammonia as N – 290
Biochemical oxygen demand (BOD) 600 510
Chloride 200 160
Sulfate as SO4 – 930
Sulfide and/or sulfite 1.0 (2)
Total dissolved solids (TDS) 1,000 2,000
Total suspended solids (TSS) 500 490
Metals (total recoverable)
Arsenic 1.0 0.17
Boron 1.0 1.0
Cadmium 0.8 0.075
Chromium 2.5 1.5
Copper 2.0 0.33
Fluoride 3.0 (2)
Lead 0.6 0.49
Mercury 0.01 0.0057
Molybdenum – 0.72
Nickel 2.0 1.9
Selenium 0.1 0.28
Silver 0.5 1.0
Zinc 5.0 5.0 (3)
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Pollutant Existing Local Limit
(mg/L)
Proposed Local
Limit as Daily
Maximum
(mg/L) (1)
Organics
Phenols 1.0 (2)
Total Identifiable Chlorinated
Hydrocarbons 0.05 (2)
Other Toxics
Cyanide 2.5 0.086
(1) Based on average influent and effluent flow rates of 8.67 mgd and 8.55 mgd, respectively (July 2019 - June 2022 average daily flow).
(2) The existing local limit will be removed based on the April 2020 Local Limits Evaluation. (3) The City proposes to maintain its existing local limit for zinc. A local limit could not be calculated because the domestic source contributions exceeded the MAIL. The zinc discharge from HCTP is well below the lowest applicable water quality criterion and HCTP has not experience treatment inhibition. The City will continue to collect data and re-evaluate the local limit for zinc in the future.
An updated local limit for zinc was not calculated because the pollutant load from uncontrollable sources (e.g., non-industrial) is equivalent to the MAHL leaving no available allocation for industrial users. As discussed previously, there were potential issues with collection system sampling for several samples where excess sediment was likely pulled into the sample resulting in abnormally high concentrations of TSS and metals. While these sample results were excluded from this analysis, further collection system sampling may be conducted to better characterize contributions from uncontrollable sources. The City does not currently have an NPDES permit effluent limitation for zinc, observed effluent concentrations (maximum effluent concentration of 46 µg/L) exceeding the lowest applicable water quality objective (311 µg/L), or experience treatment inhibition. The City will retain the existing local limit, continue to evaluate this pollutant in the future to determine the need for an updated local limit in the future.
As described in the Local Limits Evaluation (Appendix A), the City proposes to remove existing local limits for phenols, total identifiable chlorinated hydrocarbons, sulfide/sulfite, and fluoride.
The Local Limits Evaluation assessed each individual pollutant that is part of the group of phenols and total identifiable chlorinated hydrocarbons, and it was determined that local limits were not needed for those pollutants. There are no environmental or operational restrictions to justify maintaining a fluoride local limit. This was likely a pollutant that had an NPDES permit effluent limitation in the past that provided a need for implementing a local limit. Local limits sampling data collected for sulfide indicate that it is not a pollutant of concern, which justifies the removal of the existing local limit.
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PUBLIC PARTICIPATION
General Pretreatment Regulations encourage public participation by requiring public notices or hearings for Pretreatment Program approval, removal credits, program revisions, local limits development and revisions, and permitted users in significant non-compliance. For a substantial modification to the Pretreatment Program, such as the development less stringent local limits or removal of existing local limits, the City is required to notify the Los Angeles Water Board of its desire to modify its program and its basis for the changes. The requested modifications cannot be implemented until the City receives approval from the Los Angeles Water Board of the modifications. For non-substantial modifications to the Pretreatment Program, such as the development of new or more stringent local limits, the City is required to notify the Los Angeles Water Board of its desire to modify its program and its basis for the changes at least forty-five (45) days prior to implementation of the modifications. If the Los Angeles Water Board does not notify the City within 45 days of its decision to approve or deny the modification or to treat the modification as substantial, the City can implement the non-substantial modifications.
Federal regulations [40 CFR Part 403.5(c)(3)] require POTWs notify permitted users and other affected parties and provide them with an opportunity to respond to changes in local limits. The federal regulations do not specify the exact public notice process, but USEPA recommends that the POTWs notify affected parties in the local newspaper when the new local limits are proposed. This public comment period can be open while the proposed local limits are being submitted to the regulatory agency (i.e., Los Angeles Water Board) for initial review or a POTW can wait until after it receives comments from the regulatory agency. During the comment period, the public may present technical challenges to the rationale for a particular local limit. To prepare for potential challenges, a POTW should thoroughly document its local limits development process.
For this local limits development process, the City will provide a public notice and public comment period during the first reading at City Council after the proposed local limits are submitted to the Los Angeles Water Board for initial review. Additionally, the City will send letters to its industrial users to notify them of the proposed revisions to the local limits. The City requires a second reading to adopt the changes into its Sewer Use Ordinance.
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NEXT STEPS
The proposed local limits update is part of a dynamic process that includes periodic review and update as necessary. The 2004 Local Limits Guidance recommends that POTWs conduct regular monitoring as part of the local limits evaluation process. Recommended monitoring frequencies are presented in Table 9. It should be noted that more frequent monitoring may be required through other permits and/or regulations.
Table 9. Local Limits Monitoring Program – Recommended On-going Monitoring Frequency Location POCs with Local Limits (1)
Collection System Annually
HCTP Influent Semiannually
HCTP Primary Effluent Semiannually
HCTP Final Effluent Semiannually
HCTP Biosolids Disposal Point Annually
(1) This refers to POCs that have proposed local limits (i.e., Table 8 POCs).
Future circumstances may create a need to update The City’s MAILs to allow for the compliance with environmental and operational restrictions. Such circumstances may include the following:
• Significant changes in the City’s industrial user base. • Significant changes in the discharge characteristics of existing users. • Significant changes in the environmental and/or NPDES permit regulations applicable to the City.
• Facility operational difficulties, discharge compliance difficulties, or biosolids disposal compliance difficulties from any pollutants known or suspected to be significantly contributed from controllable sources.
• Facility infrastructure upgrades that can affect wastewater and/or biosolids treatment processes and quality.
• Difficulties in meeting local limits without any corresponding facility operational challenges, discharge compliance challenges, or biosolids disposal compliance challenges.
The City intends to adopt the proposed local limits presented in Table 8. Following the Los Angeles Water Board’s approval of the local limits, the City will implement the updated local limits in its wastewater discharge permits.
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REFERENCES
California Regional Water Quality Control Board, Los Angeles Region. Waste Discharge Requirements for the City of Thousand Oaks Hill Canyon Treatment Plant (Order No. R4-2019- 0137, NPDES No. CA0056294), November 14, 2019.
CH2M Hill and RMI. Local Limits Calculations. January 24, 1994.
EOA, Inc. Local Limits Update. November 2004.
Larry Walker Associates, Inc. City of Thousand Oaks Local Limits Evaluation. April 2020.
Larry Walker Associates, Inc. City of Thousand Oaks Local Limits Sampling Plan. May 2022.
United States Environmental Protection Agency. Local Limits Development Guidance. July 2004.
United States Environmental Protection Agency. Guidance Manual on the Development and Implementation of Local Discharge Limitations under the Pretreatment Program. December 1987.
United States Environmental Protection Agency. Sampling Ambient Water for Determination of Metals at EPA Water Quality Criteria Levels (Method 1669). April 1995.
APPENDIX
Appendix A: Local Limits Evaluation (April 2020)
Appendix B: Local Limits Sampling Plan (May 2022)
Appednix C: Local Limits Development Guidance
Inhibition Levels; Biosolids Disposal Regulations; NPDES Permit Effluent Limitations
Appendix D: Local Limits Data Summary
Appendix E: Local Limits Calculations
Appendix F: Local Limits Calculations Documentation/
Assumptions
APPENDIX A
Local Limits Evaluation (April 2020)
City of Thousand Oaks 1 April 2020
Hill Canyon Treatment Plant
Memorandum
Gorman Lau, P.E.
1480 Drew Avenue, Suite 100
Davis, CA 95618
530.753.6400 (phone)
530.753.7030 (fax)
[email protected]
DATE: April 28, 2020
TO: Paul Jorgensen, City of Thousand
Oaks
SUBJECT: Local Limits Evaluation
cc:
INTRODUCTION
Local limits development and implementation are a requirement of the National Pretreatment Program and the City of Thousand Oaks (City) National Pollutant Discharge Elimination System (NPDES) permit (CA0056294, Order No. R4-2019-0137), which was adopted by the Los Angeles Regional Water Quality Control Board ( Los Angeles Water Board) in November 2019. Local limits are effluent quality limits that regulate the discharge of industrial wastewater at the point in which the industrial user connects to the collection system.
The NPDES permit (Attachment I, Section B) required that the City conduct a technical evaluation to determine if the City’s local limits needed to be revised. The purpose of this technical memorandum is to summarize an evaluation of monitoring data from September 2016 through August 2019 to determine if the City’s local limits adequately protect the Hill Canyon Treatment Plant (HCTP) from process upset and/or inhibition, protect biosolids quality, meet NPDES permit effluent limitations, and protect worker health and safety.
The major elements of this technical memorandum include the following:
• Background;
• Local limits evaluation;
• Compliance history review; and
• Summary and recommendations.
Local Limits Evaluation
City of Thousand Oaks 2 April 2020
Hill Canyon Treatment Plant
BACKGROUND
Hill Canyon Treatment Plant Process Description
The HCTP is a tertiary-level treatment facility with an average dry weather design capacity of 14 million gallons per day (m gd) that treats domestic, commercial, and industrial wastewater from the City . Wastewater treatment consists of screening , primary clarification, activated sludge and nitrogen removal using the Modified Ludzack-Ettinger (MLE) biological nutrient removal (B NR) process, flow equalization (if necessary), secondary clarifiers, filtration, chlorination with sodium hypochlorite, and dechlorination with sodium bisulfite. Final effluent is discharged to North Fork Arroyo Conejo.
Grit and screenings are hauled off -site for disposal in a landfill. Sludge from secondary clarification is pumped to gravity belt thickeners. Dewatered sludge is either further solar dried and ha uled off for disposal at a landfill or hauled directly to the landfill from the gravity belt thickeners.
Pretreatment Program
The City operates a Pretreatment Program to regulate wastewater under the authority of Title 10 of the City of Thousand Oaks Munic ipal Code . Through the Pretreatment Program, the City regulates a total of six significant industrial users (SIUs), of which three are categorical industrial users (CIUs). The City also implements a Fats, Oils, and Grease (FOG) program to mitigate FOG primarily from the restaurants in its service area.
As part of its Pretreatment Program, the City currently implements local limits for arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, zinc, cyanide, phenols, total identifiable chlorinated hydrocarbons, biochemical oxygen demand (BOD), boron, chloride, fluoride, oil and grease, sulfide, total dissolved solids (TDS), and total suspended solids (TSS). It appears that most of the current local limits pre- date 1994.
The City conducted a local limits update in 1994
1 (1994 Local Limits Calculations), but it
does not appear tha t the proposed local limits from that study were implemented. The City most recently completed a local limits evaluation in 20042 (2004 Local Limits Update) and determined that the current local limits did not need to be updated.
1 CH2M Hill and RMI. Local Limits Calculations. January 24, 1994. 2 EOA, Inc. Local Limits Update. November 2004.
Local Limits Evaluation
City of Thousand Oaks 3 April 2020
Hill Canyon Treatment Plant
LOCAL LIMITS EVALUATION
As part of this local limits evaluation, recent monitoring data ( September 2016 through August 2019) were evaluated to assess if the current local limits are sufficiently protective, update the list of pollutants of concern ( POCs), determine if local limi ts for these POCs need to be developed and/or updated, and identify any additional monitoring to obtain data to update the City’s local limits.
Pollutants of Concern
The pollutants currently with local limits and recent monitoring data were reviewed to create a list of potential POCs. A summary of potential POCs that are national POCs, have NPDES permit effluent limitations, cause treatment process inhibition, or have biosolids restrictions are presented in Table 1.
Table 1. City of Thousand Oaks Hill Canyon Treatment Plant Potential Pollutants of Concern Pollutant National
POCs
NPDES Permit
Effluent
Limitations
Treatment
Process
Inhibition
Biosolids
Restrictions
Conventional
Ammonia as N X X X
Biochemical oxygen demand (1) X X X
Chloride (1) X
Fluoride (1)
Oil & Grease (1) X
Sulfate as SO4 X X
Sulfide as S (1) X
Surfactants (MBAS) X X
Total dissolved solids (1) X
Total suspended solids (1) X X X
Metals
Antimony X
Arsenic (1) X X X
Barium X
Beryllium X
Boron (1) X
Cadmium (1) X X X
Chromium (1) X X X
Cobalt X
Copper (1) X X X X
Local Limits Evaluation
City of Thousand Oaks 4 April 2020
Hill Canyon Treatment Plant
Pollutant National
POCs
NPDES Permit
Effluent
Limitations
Treatment
Process
Inhibition
Biosolids
Restrictions
Lead (1) X X X
Mercury (1) X X X X
Molybdenum X X
Nickel (1) X X X X
Selenium (1) X X
Silver (1) X X X
Thallium X
Vanadium X
Zinc (1) X X X
Volatile Organics
1,2-Dichlorobenzene X
1,3-Dichlorobenzene X
1,4-Dichlorobenzene X
Acrylonitrile X
Benzene X
Carbon tetrachloride X
Chlorobenzene X
Chloroform X
Ethylbenzene X
Methyl chloride X
Methylene chloride
Tetrachloroethylene X
Toluene X
Trichloroethylene X X
Xylene
Semi- and Non-volatile Organics
1,2-Diphenylhydrazine X
2-Chlorophenol X
2,4-Dichlorophenol X
2,4-Dimethylphenol X
2,4-Dinitrotoluene X
2,4,6-Trichlorophenol X
Anthracene X
Bis(2-ethylhexyl)phthalate X
Local Limits Evaluation
City of Thousand Oaks 5 April 2020
Hill Canyon Treatment Plant
Pollutant National
POCs
NPDES Permit
Effluent
Limitations
Treatment
Process
Inhibition
Biosolids
Restrictions
Hexachlorobenzene X
Naphthalene X
Nitrobenzene X
Pentachlorophenol X X
Phenanthrene X
Phenol (1) X
Pesticides & PCBs
4,4’-DDD X X
4,4’-DDE X X
4,4’-DDT X X
Aldrin X
gamma-BHC X
Chlordane X X
Chlorpyrifos X
Diazinon X
Dieldrin X X
Endrin X
Heptachlor X
Methoxychlor X
PCBs X X
Toxaphene X X
Other Toxics
Cyanide (1) X X X
(1) Pollutants that currently have local limits in the City of Thousand Oaks Municipal Code.
A screening step included in the USEPA’s Guidance Manual on the Development and Implementation of Local Discharge Limitations under the Pretreatment Program (1987 Local Limits Guidance) , but not included in the USEPA’s Local Limits Development Guidance (2004 Local Limits Guidance), is a useful tool for determining if a potential POC warrants a headworks loading analysis and a subsequent local limit.
This screening step is particularly useful in determining if it is necessary to conduct a headworks loading analysis for organic pollutants that have treatment process inhibition levels, but may not have any other environmental or operational restriction to drive local limits development. Current standard laboratory detection levels are typically several orders of magnitude lower than the treatment process inhibition thresholds presented in the 2004 Local Limits Guidance and applicable biosolids disposal limitations and Local Limits Evaluation
City of Thousand Oaks 6 April 2020
Hill Canyon Treatment Plant
regulations. Additionally, most organic pollutants that h ave treatment process inhibition levels are typically not detected in wastewater, which further justifies that these pollutants be excluded from the headworks loading analysis.
The following screening step criteria were used to determine if a potential POC needs to undergo the headworks loading analysis:
• Criterion 1. The maximum concentration of the pollutant in the effluent is more than one- half the allowable effluent concentration required to meet water quality criteria/ standards or the maximum sludge concentration is more than one-half the applicable biosolids criteria guidelines; • Criterion 2. The maximum concentration of the pollutant in a grab sample from the influent is more than one-half the inhibition threshold; • Criterion 3. The maximum concentration of the pollutant in a composite sample from the influent is more than one-fourth the inhibition threshold; or • Criterion 4. The maximum concentration of the pollutant in the influent is more than 1/500th of the applicable biosolids use criteria.
Data collected between September 2016 and August 2019 were used to conduc t a screening for the pollutants listed in Table 1 except for national POCs, which are expected to have local limits . If a pollutant met any of criteri a listed above, a headworks loading analysis was conducted for the pollutant to assess if it was necessary to develop a local limit for the pollutant. A summary of the screening is presented in Attachment A.
Based on the screening, headworks loading analyses should be conducted for bis(2 - ethylhexyl)phthalate, boron, chloride, sulfate as S, and TDS in addition to the national POCs. There were insufficient available data to conduct the screening for barium, cobalt, molybdenum, sulfide as S, and vanadium. Additional data are necessary to complete the screening evaluation for these pollutants.
Maximum Allowable Headworks Loadings
Four major fact ors, including NPDES permit effluent limitations, biosolids disposal restrictions, treatment process inhibition levels, and plant design capac ity, serve as the basis for the development of local limits. For each factor, an allowable headworks loading (AHL) is calculated to determine the pollutant load that may enter the headworks without causing an exceedance of the environmental/operational res triction. After each AHL is determined, the minimum AHL is selected, and becomes the maximum allowable headworks l oading (MAHL), which is the maximum pollutant load that can enter the headworks without causing an exceedance of all environmental and operati onal restriction.
The current local limits appear to be based on MAHLs that were developed prior to the 1994 Local Limits Calculation since the proposed local limits from that study were not implemented. Updated MAHLs were calculated in the 2004 Local Limits Update, but were also not implemented. In reviewing both study reports, it was determined that there were Local Limits Evaluation
City of Thousand Oaks 7 April 2020
Hill Canyon Treatment Plant
significant changes, such as HCTP upgrades and new NPDES permit effluent limitations, that have occurred since the current l ocal limits were developed that could impact or change the local limits.
Using available historic data from September 2016 to August 2019, estimated allowable headworks loadings (AHLs) were calculated for each environmental/operational restriction for a POC. A comparison of the MA HLs calculated in 1994 and 2004 and estimated in 2019 are presented in Table 2. MAHLs could not be estimated for sulfate as SO4, boron, and molybdenum due to insufficient available data at key HCTP locations.
Table 2. City of Thousand Oaks Hill Canyon Treatment Plant Maximum Allowable Headworks Loadings
Pollutant 1994 MAHL
(lb/day) (1)
2004 MAHL
(lb/day) (2)
Estimated 2019
MAHL (lb/day) (3)
Ammonia as N – – 4,500
Biochemical oxygen demand – 34,000 16,000
Chloride – 13,000 9,300
Sulfate as SO4 – – Insufficient data
Total dissolved solids – – 59,000
Total suspended solids – 45,000 15,000
Arsenic 0.57 1.8 6.9
Boron – 81 Insufficient data
Cadmium – 0.57 1.6
Chromium 9.9 42 8.1
Copper 12 18 4.4
Lead 3.5 3.9 14
Mercury – 0.053 0.0018
Molybdenum 3.3 – Insufficient data
Nickel 8.9 13 17
Selenium – 5.5 2.8
Silver 4.2 6.3 6.7
Thallium – 0.35 (4)
Zinc 37 42 7.6
Cyanide – 0.46 0.30
4,4’-DDD – 0.0044 (4)
4,4’-DDE – 0.0044 (4)
Tetrachloroethylene – 4.9 (4)
Bis(2-ethylhexyl)phthalate 13 >2.0 0.79
Local Limits Evaluation
City of Thousand Oaks 8 April 2020
Hill Canyon Treatment Plant
(1) The 1994 MAHLs were calculated using an influent design flow rate of 12.0 mgd. (2) The 2004 MAHLs were calculated using the average January 2003 to August 2004 flow rate of
10.56 mgd.
(3) The estimated 2019 MAHLs were calculated using the average September 2016 to August 2019 flow rate of 8.32 mgd.
(4) Pollutant screening indicates that a local limit for this pollutant is not necessary.
Headworks Loading Analysis Criteria
The 2004 Local Limits Guidance provides guidelines for conducting a headworks loading analysis for pollutants to determine if a local limit needs to be updated. For pollutants that currently have local limits, the 2004 Local Limits Guidance recommends the following steps for evaluating each POC:
• If the current influent POC loading exceeds the MAHL, USEPA recommends revising the local limit (unless an investigation reveals that the elevated loading is due to an unusual, one- time event), invest igating the cause of the high loading, identifying any non- complying industries, increasing monitoring of industrial users, and considering adopting pollution prevention efforts.
• If the current influent POC loading has increased significantly from the previous year (e.g., from 55% to 75% of the MAHL), USEPA recommends investigating the cause of the increased loading, increasing monitoring for the POC, or revising the local limit.
• If the current influent POC loading is below the established threshold , USEPA recommends reviewing the pollutant periodically.
For POCs that currently have MAHLs, but do not have current local limits, the 2004 Local Limits Guidance recommends developing a local limit if any of the following thresholds are met:
• The average influent loading of the pollutant is greater than 60 percent of the MAHL;
• The maximum daily influent loading of the pollutant is greater than 80 percent of the MAHL any time in the 12 -month period preceding the headworks loading analysis; or
• Monthly average influent loading is greater than 80 percent of the average design capacity for BOD, TSS, and ammonia as N during any one month in the 12-month period preceding the headworks loading analysis.
Headworks Loading Analysis and MAHL Comparison
Influent loads were calculated as the product of the measured pollutant concentration and influent flow on the day that the pollutant was sampled. Pollutant loads for each year were statistically analyzed using regression on order statistics (ROS), which is a method that Local Limits Evaluation
City of Thousand Oaks 9 April 2020
Hill Canyon Treatment Plant
estimates summary statistics for data sets that have non- detect data. The ROS method developed probability plotting positions for each data point (detect and non-detect values) based on an ordering of the data. The log- transformation of the concentrations was regressed and fitted with a least squares line to probability plotting positions. Non-detect data points were assigned concentrations for calculation of summary statistics based on their probability plotting positions and regression line equation. Summary statistics were calculated based on detected data points and “filled- in” non- detect values. Variance summary statistics were calculated using a Tukey-Jackknife algorithm, which sequentially removed one point from the dataset, ran the analysis, and calculat ed the variance estimators as the average of each of the “n” runs of data.
The ROS method cannot be used if there are insufficient detected data to perform the analysis (i.e., less than 20 percent detected data), yet is found to provide only small errors for important summary statistics parameters (mean, median, standard deviation, and interquartile range) when less than 100 percent of the data are detected. Unless 100 percent of the data set is detected, the ROS method provides only an estimation of the data.
In cases where the ROS method could not be used due to insufficient detected data, a surrogate was used to substitute for non- detect results. According to the 2004 Local Limits Guidance, three surrogates are commonly used: the reporting limit, zero, and one- half the reporting limit. The most conservative approach is to select a surrogate equal to the reporting limit, which assumes that the pollutant concentration is the maximum possible value. On the other hand, if the surrogate is equal to zero, it ass umes that the pollutant concentration is the lowest possible value. Using one-half the reporting limit as the surrogate attempts to compromise between the two extr emes. For this local limits evaluation, the reporting limit was conservatively used for non- detect data when there were insufficient detected data to use the ROS method. This approach will help put an upper bound on the potential pollutant load while assessing its relative impact on the Plant when comparing to the MAHLs.
A comparison of the MAHLs to the a nnual average and annual maximum influent loads for POCs (except ammonia as N, BOD, and TSS) are summarized in Table 3 and Table 4, respectively. The 2004 Local Limits Guidance recommends using monthly average influent loads for conventional pollutants to compare to their respective MAHLs because wastewater treatment facilities are expected t o have capacity to consistently treat a design load of conventional pollutant s to acceptable levels for discharge. The annual maximum monthly average influent loads for ammonia as N , BOD, and TSS and percentages of respective MAHLs are provided in Table 5.
Based on this analysis with estimated MAHLs using recent data , the City may need to update its local limits for BOD, chloride, TDS, TSS, copper, mercury, and zinc . While influent loads for bis(2 -ethylhexyl)phthalate exceeded the headworks loading analysis criteria in the September 2016 to August 2017 period, more recent data are inconclusive because it was not detected in the influent.
Local Limits Evaluation
City of Thousand Oaks 10 April 2020
Hill Canyon Treatment Plant
Table 3. Comparison of Annual Average Influent Loads for Pollutants of Concern to the Maximum Allowable Headworks Load, September 2016-August 2019
Pollutant
Estimated
2019
MAHL
(lb/day) (1)
September 2016-August 2017 September 2017-August 2018 September 2018-August 2019 Annual
Average
Influent Load
(lb/day)
% of MAHL
Annual
Average
Influent Load
(lb/day)
% of MAHL
Annual
Average
Influent Load
(lb/day)
% of MAHL
Chloride 9,300 10,000 110% 6,800 73% 9,600 103%
Total dissolved
solids 59,000 43,000 73% 34,000 58% 46,000 78%
Arsenic 6.9 0.34 4.9% 0.31 4.5% 0.34 4.9%
Cadmium 1.6 0.032 2.0% 0.013 0.8% 0.014 0.9%
Chromium 8.1 0.14 1.7% 0.093 1.1% 0.14 1.7%
Copper 4.4 2.9 66% 2.8 64% 4.4 100%
Lead 14 0.064 0.5% 0.084 0.6% 0.11 0.8%
Mercury 0.0018 0.0062 340% 0.0081 450% 0.0079 440%
Nickel 17 0.28 1.6% 0.23 1.4% 0.30 1.8%
Selenium 2.8 0.076 2.7% 0.045 1.6% 0.12 4.3%
Silver 6.7 0.029 0.4% 0.011 0.2% 0.015 0.2%
Zinc 7.6 8.5 110% 9.3 120% 11 140%
Cyanide 0.30 <0.17 <57% <0.17 <57% <0.18 <60%
Bis(2-
ethylhexyl)
phthalate
0.79 0.46 58% <0.77 <97% <0.85 <110%
(1) The estimated MAHL is based on an average influent flow rate of 8.32 mgd (September 2016- August 2019).
Local Limits Evaluation
City of Thousand Oaks 11 April 2020
Hill Canyon Treatment Plant
Table 4. Comparison of Maximum Annual Influent Loads for Pollutants of Concern to the Maximum Allowable Headworks Load, September 2016-August 2018
Pollutant
Estimated
2019
MAHL
(lb/day) (1)
September 2016-August 2017 September 2017-August 2018 September 2018-August 2019 Annual
Maximum
Influent Load
(lb/day)
% of MAHL
Annual
Maximum
Influent Load
(lb/day)
% of MAHL
Annual
Maximum
Influent Load
(lb/day)
% of MAHL
Chloride 9,300 11,000 120% 7,100 76% 14,000 150%
Total dissolved
solids 59,000 48,000 81% 36,000 61% 66,000 110%
Arsenic 6.9 0.36 5.2% 0.37 5.4% 0.46 6.7%
Cadmium 1.6 0.034 2.1% 0.013 0.8% 0.018 1.1%
Chromium 8.1 0.16 2.0% 0.12 1.5% 0.23 2.8%
Copper 4.4 3.3 75% 4.1 93% 4.8 110%
Lead 14 0.066 0.5% 0.090 0.6% 0.12 0.9%
Mercury 0.0018 0.0074 410% 0.015 830% 0.020 1,100%
Nickel 17 0.33 1.9% 0.26 1.5% 0.35 2.1%
Selenium 2.8 0.10 3.6% 0.058 2.1% 0.18 6.4%
Silver 6.7 0.044 0.7% 0.019 0.3% 0.019 0.3%
Zinc 7.6 8.9 120% 11 140% 11 140%
Cyanide 0.30 <0.17 <57% <0.17 <57% <0.18 <60%
Bis(2-
ethylhexyl)
phthalate
0.79 0.82 100% <0.77 <97% <0.85 <110%
(1) The estimated MAHL is based on an average influent flow rate of 8.32 mgd (September 2016-August 2019).
Local Limits Evaluation
City of Thousand Oaks 12 April 2020
Hill Canyon Treatment Plant
Table 5. Annual Maximum Monthly Average Influent Loads for Ammonia, Biochemical Oxygen Demand, and Total Suspended Solids, September 2016-August 2018
Pollutant
Estimated
2019 MAHL
(lb/day) (1)
September 2016-
August 2017
September 2017-
August 2018
September 2018-
August 2019
Maximum
Monthly
Average
Influent
Load
(lb/day)
Maximum
Monthly
Average
Influent
Load
(lb/day)
Maximum
Monthly
Average
Influent %
of MAHL
Maximum
Monthly
Average
Influent %
of MAHL
Maximum
Monthly
Average
Influent
Load
(lb/day)
Maximum
Monthly
Average
Influent %
of MAHL
Ammonia as N 4,500 2,200 49% 2,300 51% 3,000 67%
Biochemical Oxygen Demand 16,000 22,000 140% 21,000 130% 23,000 140% Total Suspended Solids 15,000 23,000 150% 22,000 150% 28,000 190% (1) The estimated MAHL is based on an average influent flow rate of 8.32 mgd (September 2016-August 2019).
Local Limits Evaluation
City of Thousand Oaks 13 April 2020
Hill Canyon Wastewater Treatment Plant
COMPLIANCE HISTORY REVIEW
The 2004 Local Limits Guidance recommends that compliance records be examined to determine if the local limits are providing sufficient protection from pass -through and treatment plant/process inhibition and/or upset. The following areas were reviewed to determine the City’s compliance history:
• HCTP inhibition and/or upset;
• NPDES permit effluent limitations;
• Biosolids regulations; and
• Pretreatment program standards.
HCTP Inhibition and/or Upset
In 2019, high BOD and foaming were observed at the HCTP. However, these incidents did not result in inhibition or upset at the HCTP.
NPDES Permit Effluent Limitations
The City has effluent limitations for ammonia as N, BOD, boron, chloride, methylene blue active substances (MBAS), nitrate plus nitrite as N, nitrate as N, nitrite as N, oil and grease, sulfate, TDS, TSS, copper, nickel, mercury, cyanide, bis(2-ethylhexyl)phthalate, chlorpyrifos, diazinon, chlordane, 4,4’-DDD, 4,4’-DDE, 4,4’-DDT, dieldrin, polychlorinated biphenyls (PCBs), and toxaphene in its 2019 NPDES permit (Order No. R4-2019-0137).
A review of the City’s compliance history indicated that there may be difficulty meeting NPDES permit effluent limitations for copper and cyanide.
Biosolids Regulations
A review of 2018 biosolids monitoring data indicates that the City complied with all applicable biosolids regulations.
Pretreatment Program Standards
The City did not make changes to its Pretreatment Program in 2017 and 2018. The Los Angeles Water Board, through PG Environmental, most recently conducted a Pretreatment Compliance Inspection (PCI) in November 2017. The City is currently working to address the requirements and recommendations identified in the PCI Summary Report.
Local Limits Evaluation
City of Thousand Oaks 14 April 2020
Hill Canyon Treatment Plant
SUMMARY AND RECOMMENDATIONS
LWA conducted a local limits evaluation that:
• Conducted a pollutant screening and determined that current local limits for fluoride, chlorinated hydrocarbons, and phenols are not necessary; • Determined that additional data are ne eded to conduct the pollutant screening for barium, cobalt, molybdenum, sulfide as S, and vanadium; • Estimated MAHLs based on recent monitoring data. The MAHLs were estimated because t here were incomplete available data to develop updated MAHLs;
• Determined that additional data are necessary to conduct headwork loading analyses for boron and sulfate as SO4;
• Compared influent pollutant loads from September 2016 to August 2019 to the estimated MAHLs and identif ied if influent pollutant loads were increasing to assess if the City’s local limits are sufficiently protective of the HCTP;
• Determined that local limits for BOD, chloride, TDS, TSS, copper, mercury, and zinc may need to be updated. Additionally, bis(2-ethylhexyl)phthalate may need to be further investigated because the headworks loading analysis was inconclusive; and
• Reviewed the City’s compliance history and determined that the HCTP may have difficulty meeting NPDES permit effluent limitations for copper an d cyanide.
Based on the local limits evaluation, LWA recommends that the City conduct an update of its local limits because the current local limits were based on conditions prior to 1994.
Since the development of the current local limits, there have been significant changes to both the HCTP, industrial user base, regulations, and other factors that warrant a local limits update. Most of the existing data can be used to supplement the data set that needs to be developed for the local limits update. This approach will help reduce the additional sampling that is necessary to fill data gaps and costs associated with sampling and analyses.
The City prepared a draft Local Limits Sampling and Analysis Plan (December 2019) and intended to move forward with a local limits update study in Spring 2020. However, due to the health orders to shelter -in-place for COVID -19, sampling would not be representative of typical conditions to characterize wastewater , particularly with the decreased non-domestic wastewater contributions. The City will continue to evaluate the proper time to implement local limits sampling efforts during dry weather conditions to move this study forward.
ATTACHMENT A
Headworks Loading Analyses Screening for
Pollutants of Concern
Local Limits Evaluation
City of Thousand Oaks A-1 April 2020
Hill Canyon Treatment Plant
Pollutant Reason for Not Conducting Headworks Loading Analysis Conventional
Fluoride The City currently has a local limit for this pollutant. However, there are no environmental or operational restrictions to drive the development or update of a technically -based local limit . It is recommended that the City consider removing this pollutant as a local limit.
Methylene blue active
substances (MBAS)
The maximum effluent concentration (0.09 mg/L) is less than one-half of the average monthly effluent limitation (0.5 mg/L).
Nitrate as N This pollutant is typically not from sources within the service area nor observed in high concentrations or loads at the influent. This pol lutant is generated from incomplete nutrient removal during wastewater treatment. At present, a local limit for this pollutant is not necessary.
Nitrite as N This pollutant is typically not from sources within the service area nor observed in high concentrations or loads at the influent. This pollutant is generated from incomplete nutrient removal during wastewater treatment. At present, a local limit for this pollutant is not necessary.
Oil and Grease The maximum effluent concentration (J1.8 mg/L) is less than one-half of the average monthly effluent limitation (10 mg/L). A local limit is currently implemented to protect the collection system from sanitary sewer overflows.
Metals (Total Recoverable)
Antimony The maximum influent pollutant concentration (0.89 µg/L) significantly below 1/500th of the applicable biosolids use criterion (15,000 µg/L).
Beryllium The pollutant was not detected in the influent at a level (0.015 µg/L) significantly below 1/500th of the applicable biosolids use criterion (750 µg/L).
Thallium The pollutant was not detected in the influent at a level (0.028 µg/L) significantly below 1/500th of the applicable biosolids use criterion (7,000 µg/L).
Volatile Organics
1,2-Dichlorobenzene Influent grab samples were not detected at a level ( 0.33 µg/L) significantly below one- half of the activated sludge and anaerobic digester inhibition thresholds (5,000 µg/L and 230 µg/L, respectively). 1,3-Dichlorobenzene Influent grab samples were not detected at a level (0.35 µg/L) significantly below on e-half of the activated sludge inhibition threshold (5,000 µg/L).
1,4-Dichlorobenzene Influent grab samples were not detected at a level (0.37 µg/L) significantly below one- half of the activated sludge and anaerobic digester inhibition thresholds (5,000 µg/L and 1,400 µg/L, respectively).
Local Limits Evaluation
City of Thousand Oaks A-2 April 2020
Hill Canyon Treatment Plant
Pollutant Reason for Not Conducting Headworks Loading Analysis Acrylonitrile Influent grab samples were not detected at a level ( 1.8 µg/L) significantly below one- half of the anaerobic digestion inhibition threshold (5,000 µg/L).
Benzene Influent grab samples were not detected at a level (0.23 µg/L) significantly below one- half of the activated sludge inhibition threshold (100,000 µg/L).
Carbon tetrachloride Influent grab samples were not detected at a level (0.33 µg/L) significantly below one- half of the anaerobic digester inhibition threshold (2,000 µg/L).
Chlorobenzene Influent grab samples were not detected at a level (0.21 µg/L) significantly below one- half of the anaerobic digester inhibition threshold (83,000 µg/L).
Chloroform The maximum influent grab sample concentration (1.2 µg/L) is significantly below one- half of the nitrification and anaerobic digester inhibition thresholds (10,000 µg/L and 1,000 µg/L, respectively).
Ethylbenzene Influent grab samples were not detected at a level (0.17 µg/L) significantly below one- half of the anaerobic digester inhibition threshold (200,000 µg/L).
Methyl chloride Influent grab samples were not detected at a level (0.26 µg/L) significantly below one- half of the anaerob ic digestion inhibition threshold (3,300 µg/L).
Tetrachloroethylene The maximum influent grab sample concentration ( 1.7 µg/L) is significantly below one- half of the anaerobic digester inhibition threshold (20,000 µg/L).
Toluene The maximum influent concentration (4.6 µ g/L) is significantly below one- half of the anaerobi c digestion inhibition threshold (200,000 µg/L).
Trichloroethylene Influent grab samples were not detected at a level (0.37 µg/L) significantly below one- half of the anaerobic digestion inhibition threshold (1,000 µg/L) and 1/500th of the applicable biosolids use criterion (204,000 µg/L).
Semi- and Non-Volatile Organics
1,2-Diphenylhydrazine Influent composite samples were not detected at a level (1.8 µ g/L) significantly below one- fourth of the activated sludge inhibition threshold (5,000 µg/L).
2-Chlorophenol Influent composite sample s were not detected at a level ( 2.8 µg/L) significantly below one -fourth of the activated sludge inhibition threshold (5,000 µg/L).
2,4-Dichlorophenol Influent composite sample s were not detected at a level ( 2.6 µg/L) significantly below one- fourth of the activated sludge and nitrification inhibition thresholds (both 64,000 µg/L).
Local Limits Evaluation
City of Thousand Oaks A-3 April 2020
Hill Canyon Treatment Plant
Pollutant Reason for Not Conducting Headworks Loading Analysis 2,4-Dimethylphenol Influent composite samples were not detected at a level (3 µg/L) significantly below one-fourth of the activated sludge inhibition threshold (40,000 µg/L).
2,4-Dinitrophenol Influent composite samples were not detected at a level (16 µ g/L) significantly below one- fourth of the nitrification inhibition threshold (150,000 µg/L).
2,4-Dinitrotoluene Influent composite samples were not detected at a level (1.8 µ g/L) significantly below one- fourth of the activated sludge inhibition threshold (50,000 µg/L).
2,4,6-Trichlorophenol Influent composite sample s were not detected at a level ( 2.2 µg/L) significantly below one- fourth of the activated sludge inhibition threshold (50,000 µg/L).
Anthracene Influent composite samples were not detected at a level (1.7 µ g/L) significantly below one- fourth of the activated sludge inhibition threshold (500,000 µg/L).
Hexachlorobenzene Influent composite samples were not detected at a level (3.5 µg/L) below one-fourth of the activated sludge inhibition threshold (5,000 µg/L).
Naphthalene Influent composite sample s were not det ected at a level ( 2.4 µg/L) significantly below one- fourth of the activated sludge inhibition threshold (500,000 µg/L).
Nitrobenzene Influent composite sample s were not detected at a level ( 2.3 µg/L) significantly below one- fourth of the activated sludge inhibition threshold (30,000 µg/L).
Pentachlorophenol The maximum influent concentration (J3.6 µg/L) is significantly below one-fourth of the activated sludge and anaerobic digester inhibition thresholds (950 and 600 µg/L, respectively).
Phenanthrene Influent composite sample s were not detected at a level ( 1.8 µg/L) significantly below one- fourth of the activated sludge inhibition threshold (500,000 µg/L).
Phenol The maximum influent composite sample concentration (18 µ g/L) is significantly below one- fourth of the activated sludge and nitrification inhibition thresholds (50,000 and 4,000 µg/L, respectively).
Pesticides and PCBs
4,4’-DDD The pollutant was not detected in the influent at a level (0.03 µg/L) significantly below 1/500th of the applicable biosolids use criteria (100 µg/L). The pollutant was not detected in the effl uent at a level (0.003 µg/L). The method detection limit is above the average monthly effluent limitation (0.00084 µg/L). At present, a local limit for this pollutant is not necessary. It is recommended that the City continue to monitor for this pollutant and re- evaluate the need for a local limit in the future.
Local Limits Evaluation
City of Thousand Oaks A-4 April 2020
Hill Canyon Treatment Plant
Pollutant Reason for Not Conducting Headworks Loading Analysis 4,4’-DDE The pollutant was not detected in the influent at a level (0.01 µg/L) significantly below 1/500th of the applicable biosolids use criteria (100 µg/L). The pollutant was not detected in the effluent at a level (0.0025 µg/L). The method detection limit is above the average monthly effluent limitation (0.00059 µg/L). At present, a local limit for this pollutant is not necessary. It is recommended that the City continue to monitor for this pollutant and re- evaluate the need for a local limit in the future.
4,4’-DDT The pollutant was not detected in the influent at a level (0.03 µg/L) significantly below 1/500th of the applicable biosolids use criteria (100 µg/L). The pollutant was not detected in the effluent at a level (0.0031 µg/L). The method detection limit is above the average monthly effluent limitation (0.00059 µg/L). At present, a local limit for this pollutant is not necessary. It is recommended that the City continue to monitor for this pollutant and re- evaluate the need for a local limit in the future.
Aldrin The pollutant was not detected in the influent at a level (0.015 µg/L) significantly below 1/500th of the applicable biosolids use criterion (140 µg/L).
gamma-BHC The pollutant was not detected in the influent at a level (0.021 µg/L) significantly below 1/500th of the applicable biosolids use criterion (400 µg/L).
Chlordane The pollutant was not detected in the influent at a level (0.06 µg/L) significantly below 1/500th of the applicable biosolids use criterion (250 µ g/L). The pollutant was not detected in the effluent at a level (0.1 µ g/L). The method detection limit is above the average monthly effluent limitation (0.00059 µg/L). At present, a local limit for this pollutant is not necessary. It is recommended that the City continue to monitor for this pollutant and re- evaluate the need for a local limit in the future.
Chlorpyrifos There were no available HCTP data to evaluate this pollutant. Since this pollutant is banned for non-agricultural uses, a local limit for this pollutant is not recommended.
Diazinon There were no available HCTP data to evaluate this pollutant. Since this pollutant is banned for non-agricultural uses, a local limit for this pollutant is not recommended.
Dieldrin The pollutant was not detected in the influent at a level (0.021 µg/L) significantly below 1/500th of the applicable biosolids use criterion (800 µ g/L). The pollutant was not detected in the effluent at a level (0.0021 µ g/L). The method detection limit is above the average monthly effluent limitation (0.00014 µg/L). At present, a local limit for this pollutant is not necessary. It is recommended that the City continue to monitor for this pollutant and re- evaluate the need for a local limit in the future.
Endrin The pollutant was not detected in the influent at a level (0.028 µg/L) significantly below 1/500th of the applicable biosolids use criterion (20 µg/L).
Heptachlor The pollutant was not detected in the influent at a level (0.017 µg/L) significantly below 1/500th of the applicable biosolids use criterion (470 µg/L).
Local Limits Evaluation
City of Thousand Oaks A-5 April 2020
Hill Canyon Treatment Plant
Pollutant Reason for Not Conducting Headworks Loading Analysis Methoxychlor The pollutant was not detected in the influent at a level (0.054 µg/L) significantly below 1/500th of the applicable biosolids use criterion (10,000 µg/L).
PCBs The pollutant was not detected in the influent at a level (0.05 µg/L) significantly below 1/500th of the applicable biosolids use criterion (5,000 µg/L). The pollutant was not detected in the effluent at a level (0.5 µg/L). The method detection limit is above the average monthly effluent limitation (0.00017 µg/L). At present, a local limit for this pollutant is not necessary. It is recommended that the City continue to monitor for this pollutant and re- evaluate the need for a local limit in the future.
Toxaphene The pollutant was not detected in the influent at a level (0.042 µg/L) significantly below 1/500th of the applicable biosolids use criterion (500 µg/L). The pollutant was not detected in the effluent at a level (0.5 µ g/L). The method detection limit is above the average monthly effluent limitation (0.00016 µg/L). At present, a local limit for this pollutant is not necessary. It is recommended that the City continue to monitor for this pollutant and re- evaluate the need for a local limit in the future.
APPENDIX B
Local Limits Sampling Plan (May 2022)
MAY 2022
CIT Y OF THOUSAND OAKS
Local Limits Sampling Plan
Prepared by
LARRY WALKER ASSOCIATES
Local Limits Sampling Plan
City of Thousand Oaks i May 2022
Hill Canyon Treatment Plant
TABLE OF CONTENTS
INTRODUCTION ................................ ................................ ................................ ......... 1 HILL CANYON TREATMENT PLANT DESCRIPTION ................................ ................. 2 LOCAL LIMITS DEVELOPMENT APPROACH ................................ ............................ 3 Sampling Locations Identification ................................ ................................ ............. 3 Recommended Sampling Frequency ................................ ................................ ....... 4 Existing Conditions and Data Evaluation ................................ ................................ .. 4 PROPOSED LOCAL LIMITS SAMPLING PLAN ................................ .......................... 6 Pollutants of Concern ................................ ................................ ............................... 6 Sampling Locations and Schedule ................................ ................................ ........... 7 Sampling and Analysis Procedures ................................ ................................ .......... 7 QUALITY ASSURANCE/QUALITY CONTROL ................................ .......................... 10 Field Controls ................................ ................................ ................................ ......... 11 Laboratory Controls ................................ ................................ ................................ 13 Data Verification ................................ ................................ ................................ ..... 14 LOCAL LIMITS DERIVATION ................................ ................................ .................... 16 Narrative Discharge Prohibitions ................................ ................................ ............ 16 National USEPA Categorical Pretreatment Standards ................................ ............ 16 POTW-specific Local Limits ................................ ................................ .................... 16 Schedule for Local Limits Development ................................ ................................ .. 17 REFERENCES ................................ ................................ ................................ .......... 18
Local Limits Sampling Plan
City of Thousand Oaks ii May 2022
Hill Canyon Treatment Plant
LIST OF TABLES
Table 1. Minimum Recommended Sampling Frequency for Local Limits Development............... 4 Table 2. Sampling Locations and General Sampling Frequency .................................................. 7 Table 3. Sample Collection and Analysis Requirements ............................................................... 8 Table 4. Quality Assurance/Quality Control Schedule ................................................................. 11
LIST OF APPENDICES
Appendix A: Maximum Reporting Limits and Analytical Methods Appendix B: Sampling Schedule
Appendix C: Sampling Equipment List
Appendix D: Sampling Procedures
Local Limits Sampling Plan
City of Thousand Oaks 1 May 2022
Hill Canyon Treatment Plant
INTRODUCTION
The development, implementation, and periodic review/update of local discharge limitations (local limits) are requirements of the National Pretreatment Program. Local limits development, implementation, and review are part of the City of Thousand Oaks (City) Pretreatment Program, which involves strategies to control discharge of conventional and toxic pollutants entering the Hill Canyon Treatment Plant (HCTP).
The objectives of the City’s Pretreatment Program are to prevent:
• Interference with HCTP treatment operations
• Pass-through of conventional and toxic pollutants
• Contamination of municipal biosolids
• Worker exposure to chemical hazards
To meet these objectives, the City developed local limits prior to 1994, and implements them to control inputs to HCTP from industrial users. Local limits are periodically evaluated, and revised as necessary, to respond to changes in treatment plant infrastructure or operations, regulations, or industrial user base. The procedures for developing and updating local limits are described in Local Limits Development Guidance, USEPA, 2004 (2004 Local Limits Guidance). The City conducted local limits evaluations in 1994, 2004, and 2019. In the 2019 local limits evaluation, it was recommended that the City update its local limi ts because of changes to HCTP infrastructure, industrial user base, and regulations, including a new National Pollutant Discharge Elimination System (NPDES) permit (CA0056294, Order No. R4-2019-0137), which was adopted by the Los Angeles Regional Water Quality Control Board in November 2019, since the development of the current local limits.
This sampling plan is based on fulfilling data requirements specified in the 2004 Local Limits Guidance to update the City’s local limits. The major elements of this work plan include the following:
• Hill Canyon Treatment Plant description
• Local limits development approach
• Proposed local limits sampling plan
• Quality assurance/quality control
• Local limits derivation
Local Limits Sampling Plan
City of Thousand Oaks 2 May 2022
Hill Canyon Treatment Plant
HILL CANYON TREATMENT PLANT DESCRIPTION
The City owns and operates the HCTP. The HCTP provides treatment of domestic, commercial, and industrial wastewater from the City , and has an average dry weather design capacity of 14 million gallons per day (MGD). Treatment at HCTP consists of primary clarification, activated sludge and nitrogen removal using the Modified Ludzack - Ettinger (MLE) process, secondary filtration, flow equalization (if necessary), tertiary filtration, disinfection via chlorination with sodium hypochlorite and aqueous ammonia, and dechlorination with bisulfide. Treated effluent is discharged to North Fork Arroy o Conejo.
Grit and screenings are hauled off -site for disposal in a landfill. Sludge from secondary clarification is pumped to gravity belt thickeners or pumped to the MLE process as return activated sludge. Dewatered sludge is either further solar dried and hauled off for disposal at a landfill or hauled directly to the landfill from the gravity belt thickeners.
Local Limits Sampling Plan
City of Thousand Oaks 3 May 2022
Hill Canyon Treatment Plant
LOCAL LIMITS DEVELOPMENT APPROACH
The purpose of developing local limits is to prevent interference and upset of HCTP operations, protect worker health and safety, prevent pass -through of conventional and toxic pollutants, and prevent contamination of biosolids. The approach for updating and developing technically- and scientifically-based local limits is centered on the following information:
• Identification of sampling locations
• Development of sampling frequencies
• Evaluation of existing conditions
Sampling Locations Identification
The development of technically- and scientifically-based local limits relies on wastewater and biosolids quality data from the City’s collection system and at various points in the treatment process to establish:
• Uncontrollable pollutant loads
• In-plant removal efficiencies
• Biosolids quality
Uncontrollable Pollutant Loads
Uncontrollable sources of pollutants (domestic users, commercial users, inflow and infiltration, drinking water, and stormwater) typically contribute most of the flow to a wastewater treatment plant, and can result in significant pollutant loads. However, for most pollutants, uncontrollable sources contain lower pollutant concentrations compared to industrial wastewater.
To establish pollutant levels from uncontrollable sources, the collection system must be monitored in an area where there are no industrial users or industrial wastewater sources.
The 2004 Local Limits Guidance recomm ends selecting sampling points based on the size of the service area, variability in pollutant concentrations in different parts of the collection system, presence of inflow and infiltration, types and mix of commercial users, and variability in drinking water sources.
In-Plant Removal Efficiencies
In-plant removal efficiencies for pollutants are required to determine the maximum allowable headworks loading (MAHL) that can be effectively treated without overloading treatment design capacities, upsetting or inhibiting treatment processes, causing contamination of biosolids, or exceeding NPDES permit effluent limitations. W astewater quality data are collected at the influent, primary treatment effluent, and final effluent locations to obtain this information.
Local Limits Sampling Plan
City of Thousand Oaks 4 May 2022
Hill Canyon Treatment Plant
Influent wastewater quality samples must be collected at a location prior to where raw wastewater mixes with any operational recirculation flows. Primary effluent data are used to determine the pollutant removal efficiencies through primary treatment and calculate allowable headworks loadings (AHLs) that are protective of biological treatment processes. Final effluent sampling is needed to calculate overall treatment plant removal efficiencies and to determine compliance with NPDES permit effluent limitations.
Biosolids Quality
Different regulations apply depending on the biosolids disposal practice. Biosolids must be monitored to determine the presence of any pollutants at levels exceeding the applicable biosolids regulations and to derive local limits that will protect biosolids handling processes and quality.
Recommended Sampling Frequency
For local limits development, the 2004 Local Limits Guidance recommends the sampling scheme, presented in Table 1, for a wastewater treatment plant of similar size to HCTP (i.e., larger than 10 MGD).
Table 1. Minimum Recommended Sampling Frequency for Local Limits Development Parameter
Publicly Owned Treatment Works Residential/
Commercial
Influent Effluent Biosolids Collection
System
Organic priority pollutants 2 2 1 2
National pollutants of concern 14 14 2 7
POTW-specific pollutants of
concern 14 14 2 7
Biosolids percent solids (1) – – 2 –
TCLP pollutants (2) – – 1 –
Note: Samples should be 24-hour composite samples unless sampling methods for a given pollutant only allow for grab samples. Samples should be collected on consecutive days. (1) Biosolids regulations in 40 CFR Part 503 require percent solids to be determined every day that biosolids are applied to land.
(2) Conduct if biosolids are (or are likely to be) disposed of in a landfill.
Existing Conditions and Data Evaluation
The City developed its current local limits prior to 1994 using the procedures and recommendations presented in the 1987 USEPA Guidance Manual on the Development and Implementation of Local Discharge Limitations Under the Pretreatment Program Local Limits Sampling Plan
City of Thousand Oaks 5 May 2022
Hill Canyon Treatment Plant
(1987 Local Limits Guidance). The City conducted a local limits update in 1994 1 (1994 Local Limits Calculations), but it did not appear that the proposed local limits from that study were implemented. The City also completed a local limits evaluation in 20042 (2004 Local Limits Update) and determined that the current local limits did not need to be updated at that time.
Most recently, the City conducted a local limits evaluation in 2019 (2019 Local Limits Evaluation
3) that considered recent data and 2019 NPDES permit effluent limitations. In the 2019 Local Limits Evaluation, pollutants of concern (POCs) were identified and MAHLs under current flow conditions were estimated based on recent monitoring data (September 2016 to August 2019) . The 2019 Local Limits Evaluation also outlined additional information and data that were needed to further evaluate or update the City’s local limits. B ased on the findings of the 2019 Local Limits Evaluation, it was recommended that the City completely update its local limits because the current local limits were based on conditions prior to 1994. Since the development of the current local limits, there have been significant changes to the HCTP, industrial user base, regulations, and other factors that would warrant a local limits update. Additionally, most of the recent monitoring data collected by the City could be used to supplement the data set that i s needed for the local limits update.
1 CH2M Hill and RMI. Local Limits Calculations. January 24, 1994. 2 EOA, Inc. Local Limits Update. November 2004.
3 Larry Walker Associates. Local Limits Evaluation. November 2019.
Local Limits Sampling Plan
City of Thousand Oaks 6 May 2022
Hill Canyon Treatment Plant
PROPOSED LOCAL LIMITS SAMPLING PLAN
The use of reliable, scientifically defensible data is essential to local limits development.
Based on an evaluation of existing data, additional sampling data are necessary to update the City’s local limits. The following local limits sampling program is proposed to collect additional data needed to complete the local limits update. Key elements of the proposed local limits sampling program include the following:
• Pollutants of concern
• Sampling locations and schedule
• Sampling and analysis procedures
Pollutants of Concern
POCs were selected for sampling, following Local Limits Guidance and the 2019 Local Limits Evaluation, for all pollutants that have the potential to interfere with one or more of the City Pretreatment Program’s objectives. Based on the 2019 Local Limits Evaluation, additional sampling is required for the following POCs:
Conventional
Ammonia Sulfide as S
Biochemical oxygen demand Total dissolved solids
Chloride Total suspended solids
Sulfate as SO
4 Metals
Arsenic Mercury
Barium Molybdenum
Boron Nickel
Cadmium Selenium
Chromium Silver
Cobalt Vanadium
Copper Zinc
Lead
Organics
Bis(2-ethylhexyl)phthalate
Other Toxics
Cyanide
Local Limits Sampling Plan
City of Thousand Oaks 7 May 2022
Hill Canyon Treatment Plant
Sampling Locations and Schedule
For the local limits sampling effort, wastewater quality samples will be collected during dry, normal operating conditions in the collection system and HCTP influent, primary treatment effluent, and final effluent. Because the City routinely collects data at some of the sampling locations, a reduced sampling frequency is proposed compared to Local Limits Guidance for a publicly-owned treatment works (POTW) of a similar size.
A general sampling schedule is provided in Table 2. It should be noted that some pollutants will not require additional sampling, and other pollutants are required to be sampled more frequently. The pollutant -specific sampling schedule is presented in Appendix B.
Table 2. Sampling Locations and General Sampling Frequency Location
Consecutive Days of Sampling
Conventional
Pollutants
Metals and
Cyanide (1) Organics
Collection System 7 7 2
HCTP Influent 7 7 2
HCTP Primary Effluent 7 7 –
HCTP Final Effluent 7 7 2
HCTP Biosolids – (2) –
(1) Metals are total recoverable forms of arsenic, barium, boron, cadmium, chromium, cobalt, copper, lead, mercury, molybdenum, nickel, selenium, silver, vanadium, zinc. (2) Existing biosolids quality data will be used for the local limits update.
Sampling and Analysis Procedures
All HCTP sampling will be conducted such that wastewater is followed through the treatment process (i.e., primary treatment effluent sampling is initiated after influent sampling).
Depending on the pollutant sampled, both composite and grab samples will be collected.
A summary of sample collection and analysis requirements is presented in Table 3.
Recommended analytical methods and maximum reporting limits are provided in Appendix A. Sampling procedures are provided in Appendix D.
Local Limits Sampling Plan
City of Thousand Oaks 8 May 2022
Hill Canyon Treatment Plant
Table 3. Sample Collection and Analysis Requirements
Parameter Sample
Type (1)
Sample
Size (2) Container Preservation (3)
Maximum
Holding
Time
Biochemical Oxygen
Demand Composite 2000 mL Plastic None 48 hours
Chloride
Composite (4) Plastic None
28 days
Sulfate as SO4 28 days
Total Suspended
Solids
7 days
Total Dissolved Solids 7 days
Metals (total
recoverable)
Composite 500 mL Plastic HNO
3 to pH<2 6 months
Bis(2-ethylhexyl)
phthalate
Grab 1000mL amber glass None 7 days
Ammonia as N Grab 250 mL Plastic H2SO4 to pH<2 28 days
Cyanide Grab 500 mL Plastic NaOH to
pH<12
14 days
Mercury (5) Grab 250 mL glass (double-
bagged)
HCl to pH<2 28 days
Sulfide as S Grab 250 mL Plastic NaOH, Zinc
acetate
7 days
(1) Composite samples will be collected at the collection system site, HCTP influent, HCTP primary treatment effluent, and HCTP final effluent.
(2) Smaller volume size is appropriate if it meets the minimum analytical volume requirements. (3) All samples must be iced or chilled to 0-6°C.
(4) When chloride, sulfate, TDS, and TSS are sampled together, 2000 mL of sample is needed. When chloride, sulfate, and TDS are sampled together, 1000 mL of sample is needed. When only chloride is sampled, 60 mL of sample is needed.
(5) Mercury is sampled individually at the primary treatment effluent and final effluent locations. At the collection system and influent, it is sampled and analyzed from the same bottle as the other metals.
A partial list of equipment required for sample collection is presented in Appendix C. All samples must be collected using clean techniques according to EPA Method 1669 (see Appendix D). Samples must be iced or chilled to 0-6 ° C, from the time of collection to delivery to the analytical laboratory, to minimize sample degradation.
All sample containers should be labeled with the following information:
• Project name
• Sample location
• Date of sample collection
Local Limits Sampling Plan
City of Thousand Oaks 9 May 2022
Hill Canyon Treatment Plant
• Time of sample collection
• Sample collector’s initials
• Sample preservative
• Analysis to be performed
Time of sample collection is the time that a grab sample was taken or the end of the composite period for composite samples. Samples must be preserved within 15 minutes from sample collection. Sample containers must be properly labeled prior to sample collection to expedite the sampling process as well as to ensure that the proper samples are collected. Chain-of -custody forms must be completed at the time of sampling and accompany each sampling events. Coolers for storage during transport must have sufficient cooling agents to maintain sample temperature of less than 6° C.
Composite Sampling
Prior to initiating sampling efforts, composite sampler intake tubing, peristaltic silicone pump tubing, and the intake strainer must be acid-washed to minimize the potential for contamination. Composite samplers should be calibrated to ensure accurate operation.
All composite samples must be collected in clean, acid-washed borosilicate glass or high- density polyethylene (HDPE) sample containers. Specific cleaning protocols to be used are included in Appendix D.
If possible, composite samples should be taken as 24-hour flow-proportioned samples. If flow-proportioned composite samples cannot be collected, then composite samples should be 24-hour time-proportioned samples.
Grab Sampling
Grab samples should be collected at locations close to the composite sampler intake to ensure that composite and grab samples are collected at the same location. Grab samples must be collected directly into clean, laboratory -provided sample containers. If necessary, the sampl e container can be fastened to a sampling grab pole. Using this sampling technique, the “pole-side” of the container must be always directed downstream of the sample container to minimize the potential for contamination from the sampling grab pole. Grab samples are associated with the composite sample removed from the sampling unit on the same day that the grab samples are collected.
Field Measurements
At the time of grab sample collection, electrical conductivity, pH, and temperature are to be measured and recorded using equipment calibrated according to instrument specifications for all locations. Field measurements must be conducted within the shortest holding time requirements prescribed for the parameter (i.e., temperature and pH).
Local Limits Sampling Plan
City of Thousand Oaks 10 May 2022
Hill Canyon Treatment Plant
QUALITY ASSURANCE/QUALITY CONTROL
An effective quality assurance/quality control (QA/QC) plan is implemented as part of the local limits sampling program to ensure that analytical data can be used with confidence.
QA/QC procedures to be initiated include the following:
• Field controls
• Laboratory controls
• Sample chain-of-custody
• Data verification
On days when samples are collected for QA/QC purposes, extra volume (sample or blank water) may be required for analyses. When duplicate samples are collected for QA/QC purposes, double the sample volume is required for analyses. Once the filled composite containers are retrieved from the sampler, the sample is split, adhering to clean techniques, into the appropriate sample containers as specified by the analytical method.
For grab sample field duplicates, it is necessary to collect two individual grab sam ples.
After samples are split into the appropriate containers, samples are to be packaged appropriately, iced, and delivered/shipped to the analytical laboratory.
A QA/QC schedule is provided in Table 4.
Local Limits Sampling Plan
City of Thousand Oaks 11 May 2022
Hill Canyon Treatment Plant
Table 4. Quality Assurance/Quality Control Schedule
Day Quality Assurance/Quality Control Analyses (1)
Collection System
Day 0 Field blank (metals)
Day 1 Field blank (cyanide)
Day 6 Field duplicate (cyanide; metals)
HCTP Influent
Day 0 Field blank (metals)
Day 1 Field blank (cyanide; bis(2-ethylhexyl)phthalate) Day 3 Laboratory duplicate (ammonia as N; chloride; cyanide; metals; sulfide as S; sulfate as SO4; TDS)
Day 4 MS/MSD (metals; cyanide)
HCTP Primary Treatment Effluent
Day 0 Field blank (metals)
Day 1 Field blank (mercury, cyanide)
Day 3 Field duplicate (ammonia as N; chloride, cyanide; mercury; metals; sulfide as S)
HCTP Final Effluent
Day 0 Field blank (metals)
Day 1 Field blank (cyanide; mercury)
Day 5 MS/MSD (cyanide; mercury; metals)
Day 7 Laboratory duplicate (ammonia as N; chloride; cyanide; mercury; metals; sulfate as SO4; TDS)
(1) For samples identified for site- specific field duplicates, laboratory duplicates, and MS/MSD, extra sample volume may be collected and must be identified on the chain-of-custody form as the sample designated for QA/QC sample . See Table B -1 for sampling schedule and sample container requirements.
Field Controls
Field controls are QA/QC procedures that are conducted prior to and during sampling until samples are delivered to the analytical laboratory in order to minimize sampling errors and potential contamination. Field controls to be initiated include the following:
• Field logs
• Sample chain-of-custody
• Sampling equipment cleaning
• Clean techniques
• Field/equipment blanks
• Field duplicates
Local Limits Sampling Plan
City of Thousand Oaks 12 May 2022
Hill Canyon Treatment Plant
Field Logs
The purpose of field logs is to record sampling information and field observations during sampling that may explain any uncharacteristic analytical results. The field log should contain sampling information such as the date and time of sample collection, s ampling team, container identification numbers, and types of samples (composite or grab) that were collected. The field log should also document any field observations that are abnormal at the sampling location (color, odor, etc.). Field measurements for electrical conductivity, pH, and temperature should be recorded in the field log.
Sample Chain-of-Custody
Sample chain-of-custody procedures include the following:
• Proper labeling of samples
• Use of chain-of-custody forms for all samples from field to the analytical laboratory • Prompt sample delivery to the laboratory
The following notes should be added to chain-of-custody forms:
• Low detection limits for metals, cyanide, and bis(2-ethylhexyl)phthalate • Detected-but-not-quantified (DNQ), or J-flag, reporting • Field and laboratory duplicate and matrix spike/matrix spike duplicate (MS/MSD ) analyses for specific samples as noted in Table 4
Sampling Equipment Cleaning
Composite containers, tubing, and lids will be cleaned by the analytical laboratory. To ensure that equipment used for sampling is clean, field/equipment blanks will be collected at the commencement of sampling efforts to identify any potential contamination.
Clean Techniques
Clean techniques involve the use of certified clean containers for sample collection, clean powder-free nitrile gloves during sample collection and handling, acid-washed tubing for the suction line, and acid-washed silicone tubing for the peristaltic pump tubing. A discussion of clean techniques is included as Appendix D. Strict adherence to clean technique protocols will minimize the potential of field contamination.
Field/Equipment Blanks
The purpose of field/equipment blanks is to check for potential contamination that may occur during equipment handling and sample collection. Field/equipment blanks should be collected under field conditions to best simulate field procedures. Blank water used for field/equipment blank collection should be provided by the analytical laboratory performing the blank analysis. Field/equipment blanks will be generated for metals (including mercury), cyanide, and bis(2-ethylhexyl)phthalate at the collection system and Local Limits Sampling Plan
City of Thousand Oaks 13 May 2022
Hill Canyon Treatment Plant
HCTP influent, primary treatment effluent, and final effluent locations.
Because composite samplers vary in design, follow manufacturer’s instruction for instrument set -up and operation. The following steps are basic recommendations for equipment blank collection prior to composite sample collection:
1. Using clean techniques, install clean silicone pump tubing into sampler peristaltic pump. Connect the intake side of the silicone tubing to the clean intake tubing.
2. Remove the end cap from the intake end of the clean intake tubing and place the intake end of the tubing inside the full laboratory-provided blank water container. Remove the end cap from the outlet side of the silicone tubing and place the outlet end of the tubing into a clean composite container.
3. Press “pump forward” on the automatic sampler. Allow pumping to continue until the blank water has been pumped through the tubing and into the composite sample container. Then press “stop”.
4. Remove the outlet of the silicone tubing from the composite sample container and cover with a new glove or plastic bag. Then pour the blank water from the composite sample container into the appropriate pre- labeled sample container(s) while using clean techniques. Place the full sample container(s) on ice.
5. Return the outlet of the silicone tubing to the composite sample container.
Place the inlet of the intake tubing into the next container of blank water and proceed with Step 3.
6. After all composite equipment blanks have been collected, prepare and set-up the sampler for composite sample collection.
Field blanks are applicable for grab sample collection and should be collected on the same day that grab samples are collected. Field blanks are collected in the field by simply by pouring appropriate, laboratory -provided, blank water directly into pre- labeled grab sample container(s) while using clean techniques.
Field Duplicates
The purpose of field duplicates is to check for constancy in field sampling procedures.
Field duplicate analyses will be performed for all pollutants. Two separate sample containers will be collected for each analysis. One sample container is labeled as the regular sample while the other sample container is labeled the same with a designation of FDU to indicate that it is the field duplicate.
Laboratory Controls
The analytical laboratory should conduct the following QA/QC procedures:
• Standard laboratory operation and calibration procedures Local Limits Sampling Plan
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Hill Canyon Treatment Plant
• Laboratory control standards (LCS/LCSD) and method blank (MB) • Analytical batch matrix spike/matrix spike duplicate (MS/MSD) • Laboratory duplicate
Standard Laboratory Operation and Calibration Procedures The analytical laboratory must calibrate equipment according to standard laboratory procedures in order to prevent analytical inaccuracies.
Laboratory Control Standards (LCS/LCSD) and Method Blank The analytical laboratory will typically conduct laboratory control standard and method blank analyses per analytical batch of twenty samples. LCS/LCSD analyses are intended to provide information on the accuracy and precision of the analytical method and laboratory performance.
The analytical batch must meet the laboratory QA/QC acceptance criteria to certify that all results within the analytical batch are accurate and acceptable. The purpose of the method blank is to determine the presence of, if any, and extent of contamination resulting from laboratory activities. If there is contamination in the method blank, the associated data must be carefully evaluated to determine if the data are valid.
Analytical Batch Matrix Spikes/Matrix Spike Duplicates (MS/MSD) The purpose of MS/MSD analyses is to check for accuracy and precision of the laboratory analyses and to demonstrate acceptable compound recovery at the analytical laboratory.
Triple the normal sample volume ma y be required. Analytical batch MS/MSD analyses must be performed on site-specific field samples, identified in Table 4, and should be conducted, at a maximum, for every twenty samples for the following pollutants:
• Metals
• Mercury
• Cyanide
Laboratory Duplicate
The purpose of the laboratory duplicate performed on site -specific sample identified o n the chain-of-custody form is to check consistency in laboratory and analytical procedures.
Laboratory duplicates must be taken from the same sample container as the original sample.
Data Verification
After analytical results are received from the laboratory, the data will be verified with the following procedures:
• Check the adequacy of the results obtained from the analyses of blanks, spikes, Local Limits Sampling Plan
City of Thousand Oaks 15 May 2022
Hill Canyon Treatment Plant
and duplicates (according to acceptability criteria set forth in Standard Methods) • Check the data set for outlier values and, accordingly, request reanalysis of samples where appropriate
• Perform in-house verification of all analytical data results. This may include, but is not limited to:
o Check that all samples were analyzed within the maximum holding time o Check that all laboratory QA/QC parameters meet laboratory -established criteria. Any results reported outside the QA/QC acceptance range must be qualified with a narrative explaining why the sample result is or is not acceptable
Local Limits Sampling Plan
City of Thousand Oaks 16 May 2022
Hill Canyon Treatment Plant
LOCAL LIMITS DERIVATION
Users discharging to POTWs may be subject to any of the following restrictions:
• Narrative discharge prohibitions
• National USEPA categorical pretreatment standards
• POTW-specific (and possibly industry-specific) local limits Narrative Discharge Prohibitions
Narrative local limits provide non-numeric restrictions to protect against such problems as violations of final effluent, biosolids, or air quality standards, treatment process inhibition or upset, flow obstruction in the c ollection system or at the POTW, fire and explosion hazard, or work safety hazard. Narrative limits often serve as a supplement to numeric limits or are used for parameters where technically-based numeric limits are not feasible or relevant. Narrative discharge prohibitions are typically identified in the Sewer Use Ordinance and wastewater discharge permit.
National USEPA Categorical Pretreatment Standards
Categorical standards are predetermined discharge limitations, based upon best available technologies (BATs), which apply to specific categories of industries defined by existing federal regulations (Title 40 of the Code of Federal Regulations [ 40 CFR] Parts 405 through 471). Categorical standards are applied to the end of a user’s regulated process, and not necessarily at the end-of-pipe. Both categorical and local limits apply to users, as appropriate.
POTW-specific Local Limits
Numeric local limits are intended to apply to all users, as defined under the Pretreatment Program, unless specific exceptions c an be justified. Local limit derivation is typically based on the following factors:
• Final effluent and/or receiving water quality limitations • In-plant inhibition and/or upset of unit processes
• Biosolids disposal limits
• Collection system concerns (i.e., flow obstruction, corrosion, worker safety) According to Local Limits Guidance, numeric local limits can be applied by the City to users using any of the following allocation methods:
• Limits based on user contribution of a POC
• Uniform limits for all users
• User needs for POC discharge loading on a case-by-case basis • Other creative allocation methods
Local Limits Sampling Plan
City of Thousand Oaks 17 May 2022
Hill Canyon Treatment Plant
Schedule for Local Limits Development
The City is expected to conduct local limits sampling in Spring 2022 during a period where there is no precipitation. The updated local limits are anticipated to be developed by late 2022.
Local Limits Sampling Plan
City of Thousand Oaks 18 May 2022
Hill Canyon Treatment Plant
REFERENCES
California Regional Water Quality Control Board Los Angeles Region. Waste Discharge Requirements for the City of Thousand Oaks Hill Canyon Treatment Plant (NPDES NO.
CA0037788) Order No. R4-2019-0137. November 2019.
CH2M Hill and RMI. Local Limits Calculation. January 24, 1994.
Eisenberg, Olivieri, & Associates (EOA). Local Limits Update. November 2004.
Larry Walker Associates. Local Limits Evaluation (Draft). November 2019.
United States Environmental Protection Agency. Local Limits Development Guidance.
July 2004.
United States Environmental Protection Agency. Sampling Ambient Water for Determination of Metals at EPA Water Quality Criteria Levels (Method 1669). April 1995.
APPENDIX A
Maximum Reporting Limits and Analytical Methods
Local Limits Sampling Plan
City of Thousand Oaks A-1 May 2022
Hill Canyon Treatment Plant
Table A-1. Reporting Limits and Analytical Methods
Pollutant Reporting Limit Units Analytical Method
Conventional
Ammonia as N 5 mg/L EPA 350.1
Biochemical oxygen demand (BOD) 5 mg/L SM 5210B
Chloride 1 mg/L EPA 300.0
Sulfate as SO4 0.5 mg/L EPA 300.0
Sulfide as S 0.1 mg/L SM 4500-S2-D
Total Dissolved Solids (TDS) 10 mg/L SM 2540C
Total Suspended Solids (TSS) 5 mg/L SM 2540D
Metals (total recoverable)
Arsenic 1 µg/L EPA 200.8
Cadmium 0.2 µg/L EPA 200.8
Chromium 0.2 µg/L EPA 200.8
Copper 0.5 µg/L EPA 200.8
Lead 0.25 µg/L EPA 200.8
Mercury (1) 0.05 µg/L EPA 245.1
Mercury (2) 0.0005 µg/L EPA 1631E
Molybdenum 0.20 µg/L EPA 200.8
Nickel 2.0 µg/L EPA 200.8
Selenium 0.5 µg/L EPA 200.8
Silver 0.2 µg/L EPA 200.8
Zinc 10 µg/L EPA 200.8
Semi-Volatile and Non-Volatile Organics
Bis(2-ethylhexyl) phthalate 5 µg/L EPA 625.1
Other Toxics
Cyanide 5 µg/L EPA 335.4
(1) Mercury will be analyzed using this method for the collection system and HCTP influent samples. (2) Mercury will be analyzed using this method for the HCTP primary treatment effluent and final effluent samples.
APPENDIX B
Sampling Schedule
Local Limits Sampling Plan
City of Thousand Oaks B-1 May 2022
Hill Canyon Treatment Plant
Table B-1. Sampling Schedule
Sampling
Day
Samples to Collect Sample Containers
Required (1) Composite Grab
Collection System
Day 0 Metals (field blank) (2) 1 – 500 mL plastic HNO3 Day 1 BOD
Chloride
Sulfate as SO4
TDS
TSS
Metals (2)
Ammonia as N
Cyanide (+field blank)
Sulfide as S
Field parameters (3)
2 – 2 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
2 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 2 BOD
Chloride
Sulfate as SO4
TDS
TSS
Metals (2)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
2 – 2 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 3 BOD
Chloride
Sulfate as SO4
TDS
TSS
Metals (2)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
2 – 2 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 4 BOD
Chloride
Sulfate as SO4
TDS
TSS
Metals (2)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
2 – 2 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 5 BOD
Chloride
Sulfate as SO4
TDS
TSS
Metals (2)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
2 – 2 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 6 BOD
Chloride
Sulfate as SO4
TDS
TSS
Metals (+field duplicate) (2)
Ammonia as N
Cyanide (+field duplicate)
Sulfide as S
Field parameters (3)
2 – 2 L plastic
2 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
2 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Local Limits Sampling Plan
City of Thousand Oaks B-2 May 2022
Hill Canyon Treatment Plant
Sampling
Day
Samples to Collect Sample Containers
Required (1) Composite Grab
Day 7 BOD
Chloride
Sulfate as SO4
TDS
TSS
Metals (2)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
2 – 2 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
HCTP Influent
Day 0 Metals (field blank) (2) 1 – 500 mL plastic HNO3 Day 1 Chloride
Sulfate as SO4
TDS
Metals (4)
Ammonia as N
Bis(2-ethylhexyl)phthalate
(+field blank)
Cyanide (+field blank)
Sulfide as S
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
2 – 1 L amber glass
2 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 2 Chloride
Sulfate as SO4
TDS
Metals (4)
Ammonia as N
Bis(2-ethylhexyl)phthalate
Cyanide
Sulfide as S
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 1 L amber glass
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 3 Chloride
Sulfate as SO4
TDS
Metals (4)
(+laboratory duplicate)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
(+laboratory duplicate)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 4 Chloride
Sulfate as SO4
TDS
Metals (+MS/MSD) (4)
Ammonia as N
Cyanide (+MS/MSD)
Sulfide as S
Field parameters (3)
1 – 1 L plastic
3 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
3 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 5 Chloride
Sulfate as SO4
TDS
Metals (4)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 6 Chloride
Sulfate as SO4
TDS
Metals (4)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Local Limits Sampling Plan
City of Thousand Oaks B-3 May 2022
Hill Canyon Treatment Plant
Sampling
Day
Samples to Collect Sample Containers
Required (1) Composite Grab
Day 7 Chloride
Sulfate as SO4
TDS
Metals (4)
Ammonia as N
Cyanide
Sulfide as S
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
HCTP Primary Treatment Effluent
Day 0 Metals (field blank) (5) 1 – 500 mL plastic HNO3 Day 1 Chloride
Metals (5)
Ammonia as N
Mercury (+field blank)
Cyanide (+field blank)
Sulfide as S
Field parameters (3)
1 – 60 mL plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
2 – 250 mL glass (double-
bagged)
2 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 2 Chloride
Metals (5)
Ammonia as N
Mercury
Cyanide
Sulfide as S
Field parameters (3)
1 – 60 mL plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 250 mL plastic NaOH
1 – 500 mL plastic NaOH,
zinc acetate
Day 3 Chloride
Metals (5)
(+field duplicate)
Ammonia as N
Mercury
Cyanide
Sulfide as S
Field parameters (3)
(+field duplicate)
2 – 60 mL plastic
2 – 500 mL plastic HNO3
2 – 250 mL plastic H2SO4
2 – 250 mL glass (double-
bagged)
2 – 500 mL plastic NaOH
2 – 250 mL plastic NaOH,
zinc acetate
Day 4 Chloride
Metals (5)
Ammonia as N
Mercury
Cyanide
Sulfide as S
Field parameters (3)
1 – 60 mL plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 5 Chloride
Metals (5)
Ammonia as N
Mercury
Cyanide
Sulfide as S
Field parameters (3)
1 – 60 mL plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Local Limits Sampling Plan
City of Thousand Oaks B-4 May 2022
Hill Canyon Treatment Plant
Sampling
Day
Samples to Collect Sample Containers
Required (1) Composite Grab
Day 6 Chloride
Metals (5)
Ammonia as N
Mercury
Cyanide
Sulfide as S
Field parameters (3)
1 – 60 mL plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
Day 7 Chloride
Metals (5)
Ammonia as N
Mercury
Cyanide
Sulfide as S
Field parameters (3)
1 – 60 mL plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
1 – 250 mL plastic NaOH,
zinc acetate
HCTP Final Effluent
Day 0 Metals (field blank) (6) 1 – 500 mL plastic HNO3 Day 1 Chloride
Sulfate as SO4
TDS
Metals (6)
Ammonia as N
Mercury (+field blank)
Cyanide (+field blank)
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
2 – 250 mL glass (double-
bagged)
2 – 500 mL plastic NaOH
Day 2 Chloride
Sulfate as SO4
TDS
Metals (6)
Ammonia as N
Mercury
Cyanide
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
Day 3 Chloride
Sulfate as SO4
TDS
Metals (6)
Ammonia as N
Mercury
Cyanide
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
Day 4 Chloride
Sulfate as SO4
TDS
Metals (6)
Ammonia as N
Mercury
Cyanide
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
Day 5 Chloride
Sulfate as SO4
TDS
Metals (+MS/MSD) (6)
Ammonia as N
Mercury (+MS/MSD)
Cyanide (+MS/MSD)
Field parameters (3)
1 – 1 L plastic
3 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
3 – 250 mL glass (double-
bagged)
3 – 500 mL plastic NaOH
Local Limits Sampling Plan
City of Thousand Oaks B-5 May 2022
Hill Canyon Treatment Plant
Sampling
Day
Samples to Collect Sample Containers
Required (1) Composite Grab
Day 6 Chloride
Sulfate as SO4
TDS
Metals (6)
Ammonia as N
Mercury
Cyanide
Field parameters (3)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
Day 7 Chloride
Sulfate as SO4
TDS
Metals (6)
(+laboratory duplicate)
Ammonia as N
Mercury
Cyanide
Field parameters (3)
(+laboratory duplicate)
1 – 1 L plastic
1 – 500 mL plastic HNO3
1 – 250 mL plastic H2SO4
1 – 250 mL glass (double-
bagged)
1 – 500 mL plastic NaOH
(1) Sample volume and container size listed above are recommendation only. Sample size and number of containers may be reduced if the sample volume meets the minimum analytical volume criteria of the analytical laboratory.
(2) Metals (total recoverable) include arsenic, boron, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, silver, zinc
(3) Metals (total recoverable) include arsenic, barium, boron, cadmium, chromium, cobalt, copper, lead, mercury, molybdenum, nickel, selenium, silver, vanadium, zinc (4) Field parameters include electrical conductivity, pH, and temperature. (5) Metals (total recoverable) include arsenic, cadmium, chromium, copper, lead, nickel, zinc. (6) Metals (total recoverable) include arsenic, boron, cadmium, chromium, copper, lead, molybdenum, nickel, selenium, silver, zinc.
APPENDIX C
Sampling Equipment List
Local Limits Sampling Plan
City of Thousand Oaks C-1 May 2022
Hill Canyon Treatment Plant
At a minimum, the following list of equipment will be required for local limits sample collection:
• Four (4) automated peristaltic samplers for composite sample collection • New silicone tubing for the composite samplers
• Strainers for influent and collection system intake tubing • Powder-free nitrile gloves for clean sampling
• Sampling containers and field blank water listed in Tables C-1 and C-2 Table C-1. Sample Container Requirements by Sampling Site Sample Type Pollutant Sample Containers (1)
Collection System
Composite (2) BOD; chloride; sulfate as SO4; TDS; TSS 14 – 2 L plastic Metals (+1 field blank, +1 field duplicate) 9 – 500 mL plastic HNO3 Grab Ammonia as N 7 – 250 mL plastic H2SO4
Cyanide (+1 field blank, +1 field duplicate) 9 – 500 mL plastic NaOH Sulfide as S 7 – 250 mL plastic NaOH, zinc
acetate
HCTP Influent
Composite (2) Chloride; Sulfate as SO4; TDS
(+1 laboratory duplicate)
7 – 1 L plastic
Metals (+1 field blank, +1 MS/MSD, +1
laboratory duplicate)
10 – 500 mL plastic HNO3
Grab Ammonia as N (+1 laboratory duplicate) 7 – 250 mL plastic H2SO4 Bis(2-ethylhexyl)phthalate (+1 field blank) 3 – 1 L amber glass Cyanide (+1 field blank, +1 MS/MSD, +1
laboratory duplicate)
10 – 500 mL plastic NaOH
Sulfide as S (+1 laboratory duplicate) 7 – 250 mL plastic NaOH, zinc acetate
HCTP Primary Treatment Effluent
Composite (2) Chloride (+1 field duplicate) 8 – 60 mL plastic Metals (+1 field blank, +1 field duplicate) 9 – 500 mL plastic HNO3 Grab Ammonia as N (+1 field duplicate) 8 – 250 mL plastic H2SO4 Mercury (+1 field blank, +1 field duplicate) 9 – 250 mL glass HCl (double- bagged)
Cyanide (+1 field blank, +1 field duplicate) 9 – 500 mL plastic NaOH Sulfide as S (+1 field duplicate) 8 – 250 mL plastic NaOH, zinc acetate
HCTP Final Effluent
Composite (2) Chloride; Sulfate as SO4; TDS (+1 laboratory duplicate)
7 – 1 L plastic
Local Limits Sampling Plan
City of Thousand Oaks C-2 May 2022
Hill Canyon Treatment Plant
Sample Type Pollutant Sample Containers (1)
Metals (+1 field blank, +1 MS/MSD, +1
laboratory duplicate)
10 – 500 mL plastic HNO3
Grab Ammonia as N (+1 laboratory duplicate) 7 – 250 mL plastic H2SO4 Mercury (+1 field blank, +1 MS/MSD, +1
laboratory duplicate)
10 – 250 mL glass HCl (double-
bagged)
Cyanide (+1 field blank, +1 MS/MSD, +1
laboratory duplicate)
10 – 500 mL plastic NaOH
(1) Sample volume and container size listed above are recommendation only. Sample size and number of containers may be reduced if the sample volume meets the minimum analytical volume criteria of the analytical laboratory.
(2) Collected in a clean 10-liter borosilicate glass or high-density polyethylene (HPDE) bottle to be split into individual sample containers.
Table C-2. Total Number of Sample Container and Blank Water Requirements Container Type Number Blank Water
Requirements
2 L plastic 14 0
1 L plastic 14 0
1 L amber glass 3 1
500 mL HDPE HNO3 38 4
250 mL HDPE H2SO4 29 0
500 mL HDPE NaOH 38 4
250 mL HDPE NaOH, zinc acetate 22 0
250 mL glass HCl (double-bagged) 19 2
APPENDIX D
Sampling Procedures
Local Limits Sampling Plan
City of Thousand Oaks D-1 May 2022
Hill Canyon Treatment Plant
GENERAL SAMPLING PROCEDURES
All sampling will be conducted in accordance with the City’s Health and Safety Plan. “Clean sampling” techniques are required to collect and handle wastewater samples in a way that does not result in contamination, loss, or change in the chemical form of the POC. Samples are collected using rigorous protocols, based on EPA Method 1669, as summarized below:
• All sampling will be conducted by two personnel using clean- hand/dirty-hand sampling procedures.
• Samples are collected only into pre-cleaned sample containers. • Clean, powder-free nitrile gloves are required to be worn for collection of samples for metals and organic pollutants.
• Gloves are changed whenever something not known to be clean has been touched.
• For this sampling plan, clean techniques must be employed whenever handling the composite containers, lids, suction tubing, or strainers. • To reduce potential contamination, sample collection personnel must adhere to the following rules while collecting samples:
o No smoking.
o Never sample near a running vehicle. Do not park vehicles in the immediate sample collection area (even non-running vehicles).
o Do not eat or drink during sample collection.
o Do not breathe, sneeze, or cough in the direction of an open sample container.
Local Limits Sampling Plan
City of Thousand Oaks D-2 May 2022
Hill Canyon Treatment Plant
SAMPLING AND HANDLING PROCEDURES
Composite Sampling Preparation and Set-up
• Composite samples will be collected with a portable, battery-operated sampler. • The composite sampler will be thoroughly cleaned before initial use. If conditions warrant, intake tubing may be rinsed in the field at the sampling site with laboratory- grade de-ionized water only.
• One continuous piece of new silicone tubing will be used for the pump tube. One continuous piece of Teflon-coated tubing will be used for the intake tubing. The same set of tubing will be used for the entire sampling effort and any follow -up and/or rescheduled sampling events. In the event of a rescheduled sampling event, all tubing will be rinsed for three (3) minutes with laboratory-grade de- ionized water and stored in a sealed plastic bag in the labor atory refrigerator until needed.
• The sample intake tube will be as short as possible.
• An intake rinse will not be used; however, a 100-count post-purge will be used. • Metal strainers will not be used.
• Pre-cleaned 10-liter borosilicate glass or HDPE containers will be used in the composite sampler. Even if no sample is collected, the sample container will be replaced with a new sample container daily.
Daily Composite Sampling Activities
• Install new battery for sampler.
• Remove previous day’s composite sample container and pour the previous day’s composite sample into sample bottles. Rinse composite sample container with de- ionized water and install composite sample container . Alternatively, a new composite sample container can be installed.
• Add a cooling agent ( e.g., ice) into the base of the composite sampler (if necessary) to maintain sample preservation requirements. For permanent composite sampler installations, verify that refrigeration is provided and operational.
• The actual start and stop time and number of sample aliquots collected will be noted on the field logs . Unusual condition(s) and flow conditions will be noted on a field log attached to the chain-of-custody form.
• Calibrate and program composite sampler. The composite sampler will be programmed using a variable collection time sequence. Set program for composite sampling. It is recommended that one aliquot be collected manually through the composite sampler before leaving the site.
• Composite samples will be split at the HCTP laboratory into the appropriate sample containers. Samples will be transported to the analytical laboratory on ice in an ice chest.
• Deliver daily samples to laboratory for analyses.
Local Limits Sampling Plan
City of Thousand Oaks D-3 May 2022
Hill Canyon Treatment Plant
Grab Sampling Procedures
• Clean sample containers provided by the laboratory will be used to collect grab sample(s). If required, a grab pole may be used for sample collectio n. If a grab pole is used the “pole side” of the container will remain downstream of the sample container to avoid contam ination. Grab samples will be associated with the composite samples removed from the sampling unit on the same day that the grab samples are collected.
• Sample containers will be stored and transported in an ice chest.
Unusual Sampling Conditions Procedures
• If a composite sampler malfunctions or does not collect a sample, determine the cause and correct. If the cause cannot be quickly and definitively determined, use the back -up composite sampler for sample collection. Switch the tubing to the back-up composite sampler. Complete the chain-of-custody form as filed and note all observed conditions. Extend the sample collection period by the number of days needed to fulfill sampling requirements and using the same settings. Use the same intake tubing, types of containers, procedures, etc. as used during the initial sample collection events.
• If the composite sampler collects low sample volume (e.g., less than 75 percent of the sample container volume), determine the cause. If the cause cannot be determined, replace the composite sampler with the back -up composite sampler for sample collection and note on the chain- of-custody form. Switch the tubing to the back -up composite sampler. Complete the field log note all observed conditions. Extend the sample collection period by the number of days needed to fulfill the sampling requirements and using the same settings. Use the same intake tubing, types of containers, procedures, etc. as used during the initial sample collection events. Take the available sample collected to the HCTP laboratory and split into the appropriate sample containers. Determine if the sample(s) will be submitted for analyses. Composite sample analysis priority is as follows:
o Metals
o BOD; TSS
o Chloride; Sulfate as SO4; TDS
• In the event there is only one person at the sampling location, servicing the sample and restarting for the next sample is the priority within the time frame allotted. If warranted, grab sample(s) can be delayed to accommodate these other tasks first.
Provide a note on the chain-of-custody form or field log.
• If sample is compromised during splitting at the HCTP laboratory or damaged in transit, a resampling event will be extended until all samples planned are collected.
Cleaning Instructions for Composite Samplers at HCTP
• Pre-cleaned 10-liter borosilicate glass or HDPE sample containers will be used.
Even if no sample is collected, the sample container will be replaced with a new sample container daily.
Local Limits Sampling Plan
City of Thousand Oaks D-4 May 2022
Hill Canyon Treatment Plant
• All tubing will be replaced with clean tubing prior to initiation of local limits sampling. • Metal strainers must not be used.
• Sampling tubing, strainers, and composite sample containers will be acid-washed with a 1% HCl solution by soaking for one hour in 1% HCl solution followed by triple rinsing with laboratory-grade de-ionized water and allowed to air-dry.
APPENDIX C
Local Limits Development Guidance Inhibition
Levels; Biosolids Disposal Regulations; NPDES
Permit Effluent Limitations
APPENDIX G -
LITERATURE INHIBITION VALUES
Pollutant
Reported Range of Activated Sludge
Inhibition Threshold
Levels, mg/L
References*
METALS/NONMETAL INORGANICS
Ammonia 480 (4)
Arsenic 0.1 (1), (2), (3)
Cadmium 1 - 10 (2), (3)
Chromium (VI) 1 (2), (3)
Chromium (III) 10 - 50 (2), (3)
Chromium (Total) 1 - 100 (1)
Copper 1 (2), (1), (3)
Cyanide 0.1 - 5
5 (1), (2), (3)
(1)
Iodine 10 (4)
Lead 1.0 - 5.0
10 - 100
(3)
(1)
Mercury 0.1 - 1
2.5 as
(2), (3)
(1)
Nickel 1.0 - 2.5
5 (2), (3)
(1)
Sulfide 25 -30 (4)
Zinc 0.3 - 5
5 - 10
(3)
(1)
Hg (II) ORGANICS
Anthracene 500 (1)
Benzene 100 - 500
125 - 500
(3)
(1)
2-Chlorophenol 5
20 - 200
(2)
(3)
1,2 Dichlorobenzene 5 (2)
1,3 Dichlorobenzene 5 (2)
1,4 Dichlorobenzene 5 (2)
2,4-Dichlorophenol 64 (3)
2,4 Dimethylphenol 40 - (3)
2,4 Dinitrotoluene 5 (2)
1,2-Diphenylhydrazine 5 (2)
Ethylbenzene 200 (3)
Hexachlorobenzene 5 (2)
Naphthalene 500
500
500
(1)
(2)
(3)
Nitrobenzene 30 - 500
500
500
(3)
(1)
(2)
200 G-1
Reported Range of Activated Sludge
Pollutant Inhibition Threshold References*
Levels, mg/L
Pentachlorophenol 0.95 (2)
50 (3)
75 - 150 (1)
500 (1)
500 (2)
50 - 200 (3)
200 (2)
200 (1)
200 (3)
50 - 100 (1)
Surfactants 100 - 500 (4)
Phenanthrene
Phenol
Toluene
2,4,6 Trichlorophenol
Pollutant Reported Range of Trickling Filter References*Inhibition Threshold Levels, mg/L Chromium (III) 3.5 - 67.6 (1)
Cyanide 30 (1)
Pollutant Reported Range of Nitrification
Inhibition Threshold Levels, mg/L References*
METALS/NONMETAL INORGANICS
Arsenic 1.5 (2)
Cadmium 5.2 (1), (2)
Chloride 180 (4)
Chromium (VI) 1 - 10 [as (CrO4 )2-] (1)
Chromium (T) 0.25 - 1.9
1 - 100
(trickling filter)
(1), (2), (3)
(1)
Copper 0.05 - 0.48 (2), (3)
Cyanide 0.34 - 0.5 (2), (3)
Lead 0.5 (2), (3)
Nickel 0.25 - 0.5
5 (2), (3)
(1)
Zinc 0.08 - 0.5 (2), (3)
ORGANICS
Chloroform 10 (2)
2,4-Dichlorophenol 64 (3)
2,4-Dinitrophenol 150 (2)
Phenol 4
4 - 10
(2)
(3)
G-2
Pollutant
Reported Range of Anaerobic
Digestion Inhibition Threshold
Levels, mg/L
References*
METALS/NONMETAL INORGANICS
Ammonia 1500 - 8000 (4)
Arsenic 1.6 (1)
Cadmium 20 (3)
Chromium (III) 130 (3)
Chromium (VI) 110 (3)
Copper 40 (3)
Cyanide 4 - 100
1 - 4
(1)
(2), (3)
Lead 340 (3)
Nickel 10
136
(2), (3)
(1)
Silver 13 - 65** (3)
Sulfate 500 - 1000 (4)
Sulfide 50 - 100 (4)
Zinc 400 (3)
ORGANICS
Acrylonitrile 5
5 (3)
(2)
Carbon Tetrachloride 2.9 - 159.4
10 - 20
2.0 (1)
(3)
(2)
Chlorobenzene 0.96 - 3
0.96 (1)
(2)
Chloroform 1
5 - 16
10 - 16
(2)
(1)
(3)
1,2-Dichlorobenzene 0.23 - 3.8
0.23 (1)
(2)
1,4-Dichlorobenzene 1.4 - 5.3
1.4 (1)
(2)
Methyl chloride 3.3 - 536.4
100
(1)
(2)
Pentachlorophenol 0.2
0.2 -
(2)
(1)
Tetrachloroethylene 20 (2)
Trichloroethylene 1 - 20
20 20
(1)
(2)
(3)
Trichlorofluoromethane - (2)
1.8 * Total pollutant inhibition levels, unless otherwise indicated. ** Dissolved metal inhibition levels.
(1) Jenkins, D.I., and Associates. 1984. Impact of Toxics on Treatment Literature Review.
G-3
(2) Russell, L. L., C. B. Cain, and D.I. Jenkins. 1984. Impacts of Priority Pollutants on Publicly Owned Treated Works Processes: A Literature Review. 1984 Purdue Industrial Waste Conference.
(3) Anthony, R. M., and L. H. Briemburst. 1981. Determining Maximum Influent Concentrations of Priority Pollutants for Treatment Plants. Journal Water Pollution Control Federation 53(10):1457-1468.
(4) U.S. EPA. 1986, Working Document; Interferences at Publicly Owned Treatment Works.
September 1986.
Source: EPA’s Guidance Manual on the Development and Implementation of Local Discharge Limitations Under the Pretreatment Program, December 1987, pp. 3-44 to 3-49.
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California Code of Regulations
22 CA ADC § 66261.24
22 CCR § 66261.24
Cal. Admin. Code tit. 22, § 66261.24
BARCLAYS OFFICIAL CALIFORNIA CODE OF REGULATIONS
TITLE 22. SOCIAL SECURITY
DIVISION 4.5. ENVIRONMENTAL HEALTH STANDARDS FOR THE MANAGEMENT OF HAZARDOUS WASTE
CHAPTER 11. IDENTIFICATION AND LISTING OF HAZARDOUS WASTE ARTICLE 3. CHARACTERISTICS OF HAZARDOUS WASTE
This database is current through 5/2/08, Register 2008, No. 18
(a) A waste exhibits the characteristic of toxicity if representative samples of the waste have any of the following properties:
_______________________________________________________________ EPA Chemical
Hazardous Abstracts Regulatory Waste Service Level Number Contaminant Number Mg/l _______________________________________________________________ D004 Arsenic 7440-38-2 5.0
D005 Barium 7440-39-3 100.0 D018 Benzene 71-43-2 0.5
D006 Cadmium 7440-43-9 1.0
D019 Carbon tetrachloride 56-23-5 0.5
D020 Chlordane 57-74-9 0.03
§ 66261.24. Characteristic of Toxicity.
(1) when using the Toxicity Characteristic Leaching Procedure (TCLP), test Method 1311 in "Test Methods for Evaluating Solid Waste, Physical/Chemical Methods," EPA Publication SW-846, third edition and Updates (incorporated by reference in section 66260.11 of this division), the extracts from representative samples of the waste contain any of the contaminants listed in Table I of this section at a concentration equal to or greater than the respective value given in that table unless the waste is excluded from classification as a solid waste or hazardous waste or is exempted from regulation pursuant to 40 CFR section 261.4. Where the waste contains less than 0.5 percent filterable solids, the waste itself, after filtering using the methodology outlined in Method 1311, is considered to be the extract for the purposes of this section;
(A) a waste that exhibits the characteristic of toxicity pursuant to subsection (a)(1) of this section has the EPA Hazardous Waste Number specified in Table I of this section which corresponds to the toxic contaminant causing it to be hazardous;
(B) Table I - Maximum Concentration of Contaminants for the Toxicity Characteristic:
California Code of Regulations
D021 Chlorobenzene 108-90-7 100.0 D022 Chloroform 67-66-3 6.0
D007 Chromium 7440-47-3 5.0
D023 o-Cresol 95-48-7 200.0 [FN1] D024 m-Cresol 108-39-4 200.0 [FN1] D025 p-Cresol 106-44-5 200.0 [FN1] D026 Cresol 200.0 [FN1] D016 2,4-D 94-75-7 10.0
D027 1,4-Dichlorobenzene 106-46-7 7.5
D028 1,2-Dichloroethane 107-06-2 0.5
D029 1,1-Dichloroethylene 75-35-4 0.7
D030 2,4-Dinitrotoluene 121-14-2 0.13
D012 Endrin 72-20-8 0.02
D031 Heptachlor (and its epoxide) 76-44-8 0.008 D032 Hexachlorobenzene 118-74-1 0.13
D033 Hexachlorobutadiene 87-68-3 0.5
D034 Hexachloroethane 67-72-1 3.0
D008 Lead 7439-92-1 5.0
D013 Lindane 58-89-9 0.4
D009 Mercury 7439-97-6 0.2
D014 Methoxychlor 72-43-5 10.0
D035 Methyl ethyl ketone 78-93-3 200.0 D036 Nitrobenzene 98-95-3 2.0
D037 Pentachlorophenol 87-86-5 100.0 D038 Pyridine 110-86-1 5.0 [FN2] D010 Selenium 7782-49-2 1.0
D011 Silver 7440-22-4 5.0
D039 Tetrachloroethylene 127-18-4 0.7
D015 Toxaphene 8001-35-2 0.5
D040 Trichloroethylene 79-01-6 0.5
D041 2,4,5-Trichlorophenol 95-95-4 400.0 D042 2,4,6-Trichlorophenol 88-06-2 2.0
D017 2,4,5-TP (Silvex) 93-72-1 1.0
D043 Vinyl chloride 75-01-4 0.2
_______________________________________________________________
[FN1]1 If o-, m- and p-Cresol concentrations cannot be differentiated, the total cresol (D026) concentration is used. The regulatory level of total cresol is 200 mg/l. [FN2]2 Quantitation limit is greater than the calculated regulatory level. The quantitation limit therefore becomes the regulatory level .
(2) it contains a substance listed in subsections (a)(2)(A) or (a)(2)(B) of this section at a concentration in milligrams per liter of waste extract, as determined using the Waste Extraction Test (WET) described in Appendix II of this chapter, which equals or exceeds its listed soluble threshold limit concentration or at a concentration in milligrams per kilogram in the waste which equals or exceeds its listed total threshold limit concentration;
(A) Table II - List of Inorganic Persistent and Bioaccumulative Toxic Substances and Their Soluble Threshold Limit Concentration:
(STLC) and Total Threshold Limi t Concentration (TTLC) Values.
California Code of Regulations
________________________________________________________________
STLC TTLC
Wet-Weight
Substance [FNa], [FNb] mg/l mg/kg
________________________________________________________________ Antimony and/or antimony compounds 15 500
Arsenic and/or arsenic compounds 5.0 500
Asbestos 1.0
(as percent)
Barium and/or barium compounds (excluding
barite) 100 10,000 [FNc]
Beryllium and/or beryllium compounds 0.75 75
Cadmium and/or cadmium compounds 1.0 100
Chromium (VI) compounds 5 500
Chromium and/or chromium (III) compounds 5 [FNd] 2,500 Cobalt and/or cobalt compounds 80 8,000
Copper and/or copper compounds 25 2,500
Fluoride salts 180 18,000
Lead and/or lead compounds 5.0 1,000
Mercury and/or mercury compounds 0.2 20
Molybdenum and/or molybdenum compounds 350 3,500 [FNe] Nickel and/or nickel compounds 20 2,000
Selenium and/or selenium compounds 1.0 100
Silver and/or silver compounds 5 500
Thallium and/or thallium compounds 7.0 700
Vanadium and/or vanadium compounds 24 2,400
Zinc and/or zinc compounds 250 5,000
________________________________________________________________
[FNa]a STLC and TTLC values are calculated on the concentrations of the elements, not the compounds.
[FNb]b In the case of asbestos and elemental metals, the specified concentration limits apply only if the substances are in a friable, powdered or finely divided state. Asbestos includes chrysotile, amosite, crocidolite, tremolite, anthophyllite, and actinolite.In the case of asbestos and elemental metals, the specified concentration limits apply only if the substances are in a friable, powdered or finely divided state. Asbestos includes chrysotile, amosite, crocidolite, tremolite, anthophyllite, and actinolite.In the case of asbestos and elemental metals, the specified concentration limits apply only if the substances are in a friable, powdered or finely divided state. Asbestos includes chrysotile, amosite, crocidolite, tremolite, anthophyllite, and actinolite.
[FNc]c excluding barium sulfate.
[FNd]d If the soluble chromium, as determined by the TCLP set forth in Appendix I of chapter 18 of this division, is less than 5 mg/l, and the soluble chromium, as determined by the procedures set forth in Appendix II of chapter 11, equals or exceeds 560 mg/l and the waste is not otherwise identified as a RCRA hazardous waste pursuant to section 66261.100, then the waste is a non- RCRA hazardous waste.
[FNe]e Excluding molybdenum disulfide.
California Code of Regulations
_______________________________________________________
STLC TTLC
Wet Weight
Substance mg/l mg/kg
_______________________________________________________ Aldrin 0.14 1.4
Chlordane 0.25 2.5
DDT, DDE, DDD 0.1 1.0
2,4-Dichlorophenoxyacetic acid 10 100
Dieldrin 0.8 8.0
Dioxin (2,3,7,8-TCDD) 0.001 0.01
Endrin 0.02 0.2
Heptachlor 0.47 4.7
Kepone 2.1 21
Lead compounds, organic - 13
Lindane 0.4 4.0
Methoxychlor 10 100
Mirex 2.1 21
Pentachlorophenol 1.7 17
Polychlorinated biphenyls (PCBs) 5.0 50
Toxaphene 0.5 5
Trichloroethylene 204 2,040
2,4,5-Trichlorophenoxypropionic acid 1.0 10
_______________________________________________________
(B) Table III - List of Organic Persistent and Bioaccumulative Toxic Substances and Their Soluble Threshold Limit Concentration (STLC) and Total Threshold Limit Concentration (TTLC) Values:
(3) it has an acute oral LD 50 less than 2,500 milligrams per kilogram; (4) it has an acute dermal LD 50 less than 4,300 milligrams per kilogram; (5) it has an acute inhalation LC 50 less than 10,000 parts per million as a gas or vapor;
(6) it has an acute aquatic 96-hour LC 50 less than 500 milligrams per liter when measured in soft water (total hardness 40 to 48 milligrams per liter of calcium carbonate) with fathead minnows (Pimephales promelas), rainbow trout (Salmo gairdneri) or golden shiners (Notemigonus crysoleucas) according to procedures described in Part 800 of the "Standard Methods for the Examination of Water and Wastewater (16th Edition)," American Public Health Association, 1985 and "Static Acute Bioassay Procedures for Hazardous Waste Samples," California Department of Fish and Game, Water Pollution Control Laboratory, revised November 1988 (incorporated by reference, see section 66260.11), or by other test methods or test fish approved by the Department, using test samples prepared or meeting the conditions for testing as prescribed in subdivisions (c) and (d) of Appendix II of this chapter, and solubilized, suspended, dispersed or emulsified by the cited procedures or by other methods approved by the Department;
(7) it contains any of the following substances at a single or combined concentration equal to or exceeding 0.001 percent by weight:
California Code of Regulations
(0) beta-Propiolactone (BPL);
(P) Vinyl chloride (VCM);
(A) 2-Acetylaminofluorene (2-AAF);
(B) Acrylonitrile;
(C) 4-Aminodiphenyl;
(D) Benzidine and its salts;
(E) bis (Chloromethyl) ether (BCME);
(F) Methyl chloromethyl ether;
(G) 1,2-Dibromo-3-chloropropane (DBCP);
(H) 3,3'-Dichlorobenzidine and its salts (DCB);
(I) 4-Dimethylaminoazobenzene (DAB);
(J) Ethyleneimine (EL);
(K) alpha-Naphthylamine (1-NA);
(L) beta-Naphthylamine (2-NA);
(M) 4-Nitrobiphenyl (4-NBP);
(N) N-Nitrosodimethylamine (DMN);
(8) it has been shown through experience or testing to pose a hazard to human health or environment because of its carcinogenicity, acute toxicity, chronic toxicity, bioaccumulative properties or persistence in the environment.
(b) A waste containin
g one or more materials which exhibit the characteristic of toxicity because the materials have the property specified in subsection (a)(5) of this section may be classified as nonhazardous pursuant to section 66260.200 if the waste does not exhibit any other California Code of Regulations
Image 1 (0.5" X 4.25") Not available for Offline Print to STP or FAX
Image 2 (0.75" X 3.25") Not available for Offline Print to STP or FAX
characteristic of this article and is not listed in article 4 of this chapter and its head space vapor contains no such toxic materials in concentrations exceeding their respective acute inhalation LC 50 or their LC LO. The head space vapor of a waste shall be prepared, and two milliliters of it shall be sampled using a five milliliter gas-tight syringe, according to Method 5020 in "Test Methods for Evaluating Solid Waste, Physical/Chemical Methods," SW-846, 2nd edition, U.S.
Environmental Protection Agency, 1982 (incorporated by reference, see section 66260.11). The quantity in milligrams of each material, which exhibits the characteristic of toxicity because it has the property specified in subsection (a)(5) of this section, in the sampling syringe shall be determined by comparison to liquid standard solutions according to the appropriate gas chromatographic procedures in Method 8010, 8015, 8020, 8030 or 8240 in "Test Methods for Evaluating Solid Waste, Physical/Chemical Methods," SW-846, 3rd edition, U.S. Environmental Protection Agency, 1986 (incorporated by reference, see section 66260.11). The concentration of each material in the head space vapor shall be calculated using the following equation:
where C (in parts per million) is the concentration of material A in head space vapor, Q (in milligrams) is the quantity of material A in sampling syringe and MW (in milligrams per millimole) is the molecular weight of material A. Where an acute inhalation LC 50 is not available, an LC 50 measured for another time (t) may be converted to an eight-hour value with the following equation:
Eight-hour LC 50 = (t/8) x (t-hour LC 50).
(c) A waste containing one or more materials which exhibit the characteristic of toxicity because the materials have either of the properties specified in subsection (a)(3) or (a)(4) of this section may be classified as nonhazardous pursuant to section 66260.200 if the waste does not exhibit any other characteristic of this article and is not listed in article 4 of this chapter and the calculated oral LD 50 of the waste mixture is greater than 2,500 milligrams per kilogram and the calculated dermal LD 50 is greater than 4,300 milligrams per kilogram by the following equation:
where %A x is the weight percent of each component in the waste mixture and [FNT]A X is the acute oral or dermal LD 50 or the acute oral LD LO of each component.
Note: Authority cited: Sections 25141, 25159, 58004 and 58012, Health and Safety Code.
Reference: Sections 25117, 25120.2, 25141, 25159 and 25159.5, Health and Safety Code and 40 CFR Section 261.24.
California Code of Regulations
HISTORY
1. New section filed 5-24-91; effective 7-1-91 (Register 91, No. 22).
2. Amendment of table II filed 1-31-94; operative 1-31-94 (Register 94, No. 5).
3. Editorial correction of equation (Register 95, No. 36).
4. Amendment of subsection (a)(1) and Note filed 10-13-98; operative 11-12-98 (Register 98, No. 42).
5. Change without regulatory effect amending subsections (a)(3) and (c) filed 6-3-2004 pursuant to section 100, title 1, California Code of Regulations (Register 2004, No. 23).
22 CCR § 66261.24, 22 CA ADC § 66261.24
1CAC
22 CA ADC § 66261.24
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7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 1/16
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e-CFR data is current as of July 22, 2020
Title 40 → Chapter I → Subchapter O → Part 503 → Subpart B Title 40: Protection of Environment
PART 503—STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE Subpart B—Land Application
Contents
§503.10 Applicability.
§503.11 Special definitions.
§503.12 General requirements.
§503.13 Pollutant limits.
§503.14 Management practices.
§503.15 Operational standards—pathogens and vector attraction reduction. §503.16 Frequency of monitoring.
§503.17 Recordkeeping.
§503.18 Reporting.
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§503.10 Applicability.
(a) This subpart applies to any person who prepares sewage sludge that is applied to the land, to any person who applies sewage sludge to the land, to sewage sludge applied to the land, and to the land on which sewage sludge is applied. (b)(1) Bulk sewage sludge. The general requirements in §503.12 and the management practices in §503.14 do not apply when bulk sewage sludge is applied to the land if the bulk sewage sludge meets the ceiling concentrations in Table 1 of §503.13 and the pollutant concentrations in Table 3 of §503.13; the Class A pathogen requirements in §503.32(a); and one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8). (2) The Regional Administrator of EPA or, in the case of a State with an approved sludge management program, the State Director, may apply any or all of the general requirements in §503.12 and the management practices in §503.14 to the bulk sewage sludge in §503.10(b) (1) on a case-by-case basis after determining that the general requirements or management practices are needed to protect public health and the environment from any reasonably anticipated adverse effect that may occur from any pollutant in the bulk sewage sludge. 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 2/16 (c)(1) The general requirements in §503.12 and the management practices in §503.14 do not apply when a bulk material derived from sewage sludge is applied to the land if the derived bulk material meets the ceiling concentrations in Table 1 of §503.13 and the pollutant concentrations in Table 3 of §503.13; the Class A pathogen requirements in §503.32(a); and one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8). (2) The Regional Administrator of EPA or, in the case of a State with an approved sludge management program, the State Director, may apply any or all of the general requirements in §503.12 or the management practices in §503.14 to the bulk material in §503.10(c)(1) on a case-by-case basis after determining that the general requirements or management practices are needed to protect public health and the environment from any reasonably anticipated adverse effect that may occur from any pollutant in the bulk sewage sludge. (d) The requirements in this subpart do not apply when a bulk material derived from sewage sludge is applied to the land if the sewage sludge from which the bulk material is derived meets the ceiling concentrations in Table 1 of §503.13 and the pollutant concentrations in Table 3 of §503.13; the Class A pathogen requirements in §503.32(a); and one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8). (e) Sewage sludge sold or given away in a bag or other container for application to the land. The general requirements in §503.12 and the management practices in §503.14 do not apply when sewage sludge is sold or given away in a bag or other container for application to the land if the sewage sludge sold or given away in a bag or other container for application to the land meets the ceiling concentrations in Table 1 of §503.13 and the pollutant concentrations in Table 3 of §503.13; the Class A pathogen requirements in §503.32(a); and one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8). (f) The general requirements in §503.12 and the management practices in §503.14 do not apply when a material derived from sewage sludge is sold or given away in a bag or other container for application to the land if the derived material meets the ceiling concentrations in Table 1 of §503.13 and the pollutant concentrations in Table 3 of §503.13; the Class A pathogen requirements in §503.32(a); and one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8).
(g) The requirements in this subpart do not apply when a material derived from sewage sludge is sold or given away in a bag or other container for application to the land if the sewage sludge from which the material is derived meets the ceiling concentrations in Table 1 of §503.13 and the pollutant concentrations in Table 3 of §503.13; the Class A pathogen requirements in §503.32(a); and one of the vector attraction reduction requirements in §503.33 (b)(1) through (b)(8).
[58 FR 9387, Feb. 19, 1993, as amended at 64 FR 42568, Aug. 4, 1999] Back to Top
§503.11 Special definitions.
7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 3/16 (a) Agricultural land is land on which a food crop, a feed crop, or a fiber crop is grown.
This includes range land and land used as pasture.
(b) Agronomic rate is the whole sludge application rate (dry weight basis) designed:
(1) To provide the amount of nitrogen needed by the food crop, feed crop, fiber crop, cover crop, or vegetation grown on the land; and
(2) To minimize the amount of nitrogen in the sewage sludge that passes below the root zone of the crop or vegetation grown on the land to the ground water. (c) Annual pollutant loading rate is the maximum amount of a pollutant that can be applied to a unit area of land during a 365 day period. (d) Annual whole sludge application rate is the maximum amount of sewage sludge (dry weight basis) that can be applied to a unit area of land during a 365 day period. (e) Bulk sewage sludge is sewage sludge that is not sold or given away in a bag or other container for application to the land.
(f) Cumulative pollutant loading rate is the maximum amount of an inorganic pollutant that can be applied to an area of land.
(g) Forest is a tract of land thick with trees and underbrush. (h) Land application is the spraying or spreading of sewage sludge onto the land surface; the injection of sewage sludge below the land surface; or the incorporation of sewage sludge into the soil so that the sewage sludge can either condition the soil or fertilize crops or vegetation grown in the soil.
(i) Monthly average is the arithmetic mean of all measurements taken during the month. (j) Other container is either an open or closed receptacle. This includes, but is not limited to, a bucket, a box, a carton, and a vehicle or trailer with a load capacity of one metric ton or less.
(k) Pasture is land on which animals feed directly on feed crops such as legumes, grasses, grain stubble, or stover.
(l) Public contact site is land with a high potential for contact by the public. This includes, but is not limited to, public parks, ball fields, cemeteries, plant nurseries, turf farms, and golf courses.
(m) Range land is open land with indigenous vegetation. (n) Reclamation site is drastically disturbed land that is reclaimed using sewage sludge.
This includes, but is not limited to, strip mines and construction sites.
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7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 4/16 §503.12 General requirements.
(a) No person shall apply sewage sludge to the land except in accordance with the requirements in this subpart.
(b) No person shall apply bulk sewage sludge subject to the cumulative pollutant loading rates in §503.13(b)(2) to agricultural land, forest, a public contact site, or a reclamation site if any of the cumulative pollutant loading rates in §503.13(b)(2) has been reached. (c) No person shall apply domestic septage to agricultural land, forest, or a reclamation site during a 365 day period if the annual application rate in §503.13(c) has been reached during that period.
(d) The person who prepares bulk sewage sludge that is applied to agricultural land, forest, a public contact site, or a reclamation site shall provide the person who applies the bulk sewage sludge written notification of the concentration of total nitrogen (as N on a dry weight basis) in the bulk sewage sludge.
(e)(1) The person who applies sewage sludge to the land shall obtain information needed to comply with the requirements in this subpart. (2)(i) Before bulk sewage sludge subject to the cumulative pollutant loading rates in §503.13(b)(2) is applied to the land, the person who proposes to apply the bulk sewage sludge shall contact the permitting authority for the State in which the bulk sewage sludge will be applied to determine whether bulk sewage sludge subject to the cumulative pollutant loading rates in §503.13(b)(2) has been applied to the site since July 20, 1993. (ii) If bulk sewage sludge subject to the cumulative pollutant loading rates in §503.13(b) (2) has not been applied to the site since July 20, 1993, the cumulative amount for each pollutant listed in Table 2 of §503.13 may be applied to the site in accordance with §503.13(a)(2)(i).
(iii) If bulk sewage sludge subject to the cumulative pollutant loading rates in §503.13(b) (2) has been applied to the site since July 20, 1993, and the cumulative amount of each pollutant applied to the site in the bulk sewage sludge since that date is known, the cumulative amount of each pollutant applied to the site shall be used to determine the additional amount of each pollutant that can be applied to the site in accordance with §503.13(a)(2)(i).
(iv) If bulk sewage sludge subject to the cumulative pollutant loading rates in §503.13(b) (2) has been applied to the site since July 20, 1993, and the cumulative amount of each pollutant applied to the site in the bulk sewage sludge since that date is not known, an additional amount of each pollutant shall not be applied to the site in accordance with §503.13(a)(2)(i).
(f) When a person who prepares bulk sewage sludge provides the bulk sewage sludge to a person who applies the bulk sewage sludge to the land, the person who prepares the 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 5/16 bulk sewage sludge shall provide the person who applies the sewage sludge notice and necessary information to comply with the requirements in this subpart. (g) When a person who prepares sewage sludge provides the sewage sludge to another person who prepares the sewage sludge, the person who provides the sewage sludge shall provide the person who receives the sewage sludge notice and necessary information to comply with the requirements in this subpart.
(h) The person who applies bulk sewage sludge to the land shall provide the owner or lease holder of the land on which the bulk sewage sludge is applied notice and necessary information to comply with the requirements in this subpart. (i) Any person who prepares bulk sewage sludge that is applied to land in a State other than the State in which the bulk sewage sludge is prepared shall provide written notice, prior to the initial application of bulk sewage sludge to the land application site by the applier, to the permitting authority for the State in which the bulk sewage sludge is proposed to be applied. The notice shall include:
(1) The location, by either street address or latitude and longitude, of each land application site.
(2) The approximate time period bulk sewage sludge will be applied to the site. (3) The name, address, telephone number, and National Pollutant Discharge Elimination System permit number (if appropriate) for the person who prepares the bulk sewage sludge. (4) The name, address, telephone number, and National Pollutant Discharge Elimination System permit number (if appropriate) for the person who will apply the bulk sewage sludge. (j) Any person who applies bulk sewage sludge subject to the cumulative pollutant loading rates in §503.13(b)(2) to the land shall provide written notice, prior to the initial application of bulk sewage sludge to a land application site by the applier, to the permitting authority for the State in which the bulk sewage sludge will be applied and the permitting authority shall retain and provide access to the notice. The notice shall include:
(1) The location, by either street address or latitude and longitude, of the land application site.
(2) The name, address, telephone number, and National Pollutant Discharge Elimination System permit number (if appropriate) of the person who will apply the bulk sewage sludge.
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§503.13 Pollutant limits.
(a) Sewage sludge. (1) Bulk sewage sludge or sewage sludge sold or given away in a bag or other container shall not be applied to the land if the concentration of any pollutant in the sewage sludge exceeds the ceiling concentration for the pollutant in Table 1 of §503.13. 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 6/16 (2) If bulk sewage sludge is applied to agricultural land, forest, a public contact site, or a reclamation site, either:
(i) The cumulative loading rate for each pollutant shall not exceed the cumulative pollutant loading rate for the pollutant in Table 2 of §503.13; or (ii) The concentration of each pollutant in the sewage sludge shall not exceed the concentration for the pollutant in Table 3 of §503.13.
(3) If bulk sewage sludge is applied to a lawn or a home garden, the concentration of each pollutant in the sewage sludge shall not exceed the concentration for the pollutant in Table 3 of §503.13.
(4) If sewage sludge is sold or given away in a bag or other container for application to the land, either:
(i) The concentration of each pollutant in the sewage sludge shall not exceed the concentration for the pollutant in Table 3 of §503.13; or (ii) The product of the concentration of each pollutant in the sewage sludge and the annual whole sludge application rate for the sewage sludge shall not cause the annual pollutant loading rate for the pollutant in Table 4 of §503.13 to be exceeded. The procedure used to determine the annual whole sludge application rate is presented in appendix A of this part.
(b) Pollutant concentrations and loading rates—sewage sludge—(1) Ceiling concentrations.
T 1 §503.13—C C
Pollutant Ceiling concentration (milligrams per kilogram)1 Arsenic 75
Cadmium 85
Copper 4300
Lead 840
Mercury 57
Molybdenum 75
Nickel 420
Selenium 100
Zinc 7500
1Dry weight basis.
(2) Cumulative pollutant loading rates.
T 2 §503.13—C P L R
Pollutant Cumulative pollutant loading rate (kilograms per hectare) Arsenic 41
7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 7/16 Cadmium 39
Copper 1500
Lead 300
Mercury 17
Nickel 420
Selenium 100
Zinc 2800
(3) Pollutant concentrations.
T 3 §503.13—P C
Pollutant Monthly average concentration (milligrams per kilogram)1 Arsenic 41
Cadmium 39
Copper 1500
Lead 300
Mercury 17
Nickel 420
Selenium 100
Zinc 2800
1Dry weight basis.
(4) Annual pollutant loading rates.
T 4 §503.13—A P L R
Pollutant Annual pollutant loading rate (kilograms per hectare per 365 day period) Arsenic 2.0
Cadmium 1.9
Copper 75
Lead 15
Mercury 0.85
Nickel 21
Selenium 5.0
Zinc 140
(c) Domestic septage. The annual application rate for domestic septage applied to agricultural land, forest, or a reclamation site shall not exceed the annual application rate calculated using equation (1).
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Where:
AAR = Annual application rate in gallons per acre per 365 day period. 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 8/16 N = Amount of nitrogen in pounds per acre per 365 day period needed by the crop or vegetation grown on the land.
[58 FR 9387, Feb. 19, 1993, as amended at 58 FR 9099, Feb. 25, 1994; 60 FR 54769, Oct. 25, 1995]
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§503.14 Management practices.
(a) Bulk sewage sludge shall not be applied to the land if it is likely to adversely affect a threatened or endangered species listed under section 4 of the Endangered Species Act or its designated critical habitat.
(b) Bulk sewage sludge shall not be applied to agricultural land, forest, a public contact site, or a reclamation site that is flooded, frozen, or snow-covered so that the bulk sewage sludge enters a wetland or other waters of the United States, as defined in 40 CFR 122.2, except as provided in a permit issued pursuant to section 402 or 404 of the CWA. (c) Bulk sewage sludge shall not be applied to agricultural land, forest, or a reclamation site that is 10 meters or less from waters of the United States, as defined in 40 CFR 122.2, unless otherwise specified by the permitting authority. (d) Bulk sewage sludge shall be applied to agricultural land, forest, a public contact site, or a reclamation site at a whole sludge application rate that is equal to or less than the agronomic rate for the bulk sewage sludge, unless, in the case of a reclamation site, otherwise specified by the permitting authority.
(e) Either a label shall be affixed to the bag or other container in which sewage sludge that is sold or given away for application to the land, or an information sheet shall be provided to the person who receives sewage sludge sold or given away in an other container for application to the land. The label or information sheet shall contain the following information:
(1) The name and address of the person who prepared the sewage sludge that is sold or given away in a bag or other container for application to the land. (2) A statement that application of the sewage sludge to the land is prohibited except in accordance with the instructions on the label or information sheet. (3) The annual whole sludge application rate for the sewage sludge that does not cause any of the annual pollutant loading rates in Table 4 of §503.13 to be exceeded.
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§503.15 Operational standards—pathogens and vector attraction reduction. (a) Pathogens—sewage sludge. (1) The Class A pathogen requirements in §503.32(a) or the Class B pathogen requirements and site restrictions in §503.32(b) shall be met when 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 9/16 bulk sewage sludge is applied to agricultural land, forest, a public contact site, or a reclamation site.
(2) The Class A pathogen requirements in §503.32(a) shall be met when bulk sewage sludge is applied to a lawn or a home garden.
(3) The Class A pathogen requirements in §503.32(a) shall be met when sewage sludge is sold or given away in a bag or other container for application to the land. (b) Pathogens—domestic septage. The requirements in either §503.32 (c)(1) or (c)(2) shall be met when domestic septage is applied to agricultural land, forest, or a reclamation site.
(c) Vector attraction reduction—sewage sludge. (1) One of the vector attraction reduction requirements in §503.33 (b)(1) through (b)(10) shall be met when bulk sewage sludge is applied to agricultural land, forest, a public contact site, or a reclamation site. (2) One of the vector attraction reduction requirements in §503.33 (b)(1) through (b)(8) shall be met when bulk sewage sludge is applied to a lawn or a home garden. (3) One of the vector attraction reduction requirements in §503.33 (b)(1) through (b)(8) shall be met when sewage sludge is sold or given away in a bag or other container for application to the land.
(d) Vector attraction reduction—domestic septage. The vector attraction reduction requirements in §503.33(b)(9), (b)(10), or (b)(12) shall be met when domestic septage is applied to agricultural land, forest, or a reclamation site.
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§503.16 Frequency of monitoring.
(a) Sewage sludge. (1) The frequency of monitoring for the pollutants listed in Table 1, Table 2, Table 3 and Table 4 of §503.13; the pathogen density requirements in §503.32(a) and §503.32(b)(2); and the vector attraction reduction requirements in §503.33 (b)(1) through (b)(4) and §503.33 (b)(7) through (b)(8) shall be the frequency in Table 1 of §503.16.
T 1 §503.16—F M —L A Amount of sewage sludge1 (metric tons per 365 day period) Frequency Greater than zero but less than 290 Once per year.
Equal to or greater than 290 but less than 1,500 Once per quarter (four times per year).
Equal to or greater than 1,500 but less than 15,000 Once per 60 days (six times per year).
Equal to or greater than 15,000 Once per month (12 times per year). 1Either the amount of bulk sewage sludge applied to the land or the amount of sewage sludge prepared for sale or give-away in a bag or other container for application to the land (dry weight basis).
7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 10/16 (2) After the sewage sludge has been monitored for two years at the frequency in Table 1 of §503.16, the permitting authority may reduce the frequency of monitoring for pollutant concentrations and for the pathogen density requirements in §503.32(a)(5)(ii) and (a)(5)(iii). (b) Domestic septage. If either the pathogen requirements in §503.32(c)(2) or the vector attraction reduction requirements in §503.33(b)(12) are met when domestic septage is applied to agricultural land, forest, or a reclamation site, each container of domestic septage applied to the land shall be monitored for compliance with those requirements. (Approved by the Office of Management and Budget under control number 2040-0157) [58 FR 9387, Feb. 19, 1993, as amended at 64 FR 42569, Aug. 4, 1999] Back to Top
§503.17 Recordkeeping.
(a) Sewage sludge. (1) The person who prepares the sewage sludge in §503.10(b)(1) or (e) shall develop the following information and shall retain the information for five years:
(i) The concentration of each pollutant listed in Table 3 of §503.13 in the sewage sludge. (ii) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the Class A pathogen requirements in §503.32(a) and the vector attraction reduction requirement in [insert one of the vector attraction reduction requirements in §503.33(b)(1) through §503.33(b)(8)] was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment.
(iii) A description of how the Class A pathogen requirements in §503.32(a) are met. (iv) A description of how one of the vector attraction reduction requirements in §503.33 (b)(1) through (b)(8) is met.
(2) The person who derives the material in §503.10 (c)(1) or (f) shall develop the following information and shall retain the information for five years:
(i) The concentration of each pollutant listed in Table 3 of §503.13 in the material. (ii) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the Class A pathogen requirements in §503.32(a) and the vector attraction reduction requirement in (insert one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8)) was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment.
(iii) A description of how the Class A pathogen requirements in §503.32(a) are met. 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 11/16 (iv) A description of how one of the vector attraction reduction requirements in §503.33 (b)(1) through (b)(8) is met.
(3) If the pollutant concentrations in §503.13(b)(3), the Class A pathogen requirements in §503.32(a), and the vector attraction reduction requirements in either §503.33 (b)(9) or (b) (10) are met when bulk sewage sludge is applied to agricultural land, forest, a public contact site, or a reclamation site:
(i) The person who prepares the bulk sewage sludge shall develop the following information and shall retain the information for five years. (A) The concentration of each pollutant listed in Table 3 of §503.13 in the bulk sewage sludge.
(B) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the Class A pathogen requirements in §503.32(a) was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment.
(C) A description of how the pathogen requirements in §503.32(a) are met. (ii) The person who applies the bulk sewage sludge shall develop the following information and shall retain the information for five years. (A) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the management practices in §503.14 and the vector attraction reduction requirement in (insert either §503.33(b) (9) or (b)(10)) was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (B) A description of how the management practices in §503.14 are met for each site on which bulk sewage sludge is applied.
(C) A description of how the vector attraction reduction requirements in either §503.33(b) (9) or (b)(10) are met for each site on which bulk sewage sludge is applied. (4) If the pollutant concentrations in §503.13(b)(3) and the Class B pathogen requirements in §503.32(b) are met when bulk sewage sludge is applied to agricultural land, forest, a public contact site, or a reclamation site:
(i) The person who prepares the bulk sewage sludge shall develop the following information and shall retain the information for five years:
(A) The concentration of each pollutant listed in Table 3 of §503.13 in the bulk sewage sludge.
7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 12/16 (B) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the Class B pathogen requirements in §503.32(b) and the vector attraction reduction requirement in (insert one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8)if one of those requirements is met) was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (C) A description of how the Class B pathogen requirements in §503.32(b) are met. (D) When one of the vector attraction reduction requirements in §503.33 (b)(1) through (b)(8) is met, a description of how the vector attraction reduction requirement is met. (ii) The person who applies the bulk sewage sludge shall develop the following information and shall retain the information for five years. (A) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the management practices in §503.14, the site restrictions in §503.32(b)(5), and the vector attraction reduction requirement in (insert either §503.33(b)(9) or (b)(10) if one of those requirements is met) was prepared for each site on which bulk sewage sludge is applied under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (B) A description of how the management practices in §503.14 are met for each site on which bulk sewage sludge is applied.
(C) A description of how the site restrictions in §503.32(b)(5) are met for each site on which bulk sewage sludge is applied.
(D) When the vector attraction reduction requirement in either §503.33 (b)(9) or (b)(10) is met, a description of how the vector attraction reduction requirement is met. (E) The date bulk sewage sludge is applied to each site. (5) If the requirements in §503.13(a)(2)(i) are met when bulk sewage sludge is applied to agricultural land, forest, a public contact site, or a reclamation site:
(i) The person who prepares the bulk sewage sludge shall develop the following information and shall retain the information for five years. (A) The concentration of each pollutant listed in Table 1 of §503.13 in the bulk sewage sludge.
(B) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the pathogen requirements in (insert either §503.32(a) or §503.32(b)) and the vector attraction reduction requirement in (insert one of the vector attraction reduction requirements in §503.33(b)(1) through (b)(8) if one of those requirements is met) was prepared under my direction and supervision in accordance with the system 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 13/16 designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (C) A description of how the pathogen requirements in either §503.32 (a) or (b) are met. (D) When one of the vector attraction requirements in §503.33 (b)(1) through (b)(8) is met, a description of how the vector attraction requirement is met. (ii) The person who applies the bulk sewage sludge shall develop the following information, retain the information in §503.17 (a)(5)(ii)(A) through (a)(5)(ii)(G) indefinitely, and retain the information in §503.17 (a)(5)(ii)(H) through (a)(5)(ii)(M) for five years. (A) The location, by either street address or latitude and longitude, of each site on which bulk sewage sludge is applied.
(B) The number of hectares in each site on which bulk sewage sludge is applied. (C) The date bulk sewage sludge is applied to each site. (D) The cumulative amount of each pollutant (i.e., kilograms) listed in Table 2 of §503.13 in the bulk sewage sludge applied to each site, including the amount in §503.12(e)(2)(iii). (E) The amount of sewage sludge (i.e., metric tons) applied to each site. (F) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the requirement to obtain information in §503.12(e)(2) was prepared for each site on which bulk sewage sludge was applied under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (G) A description of how the requirements to obtain information in §503.12(e)(2) are met. (H) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the management practices in §503.14 was prepared for each site on which bulk sewage sludge was applied under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (I) A description of how the management practices in §503.14 are met for each site on which bulk sewage sludge is applied.
(J) The following certification statement when the bulk sewage sludge meets the Class B pathogen requirements in §503.32(b):
I certify, under penalty of law, that the information that will be used to determine compliance with the site restrictions in §503.32(b)(5) for each site on which Class B sewage sludge was applied was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. 7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 14/16 (K) A description of how the site restrictions in §503.32(b)(5) are met for each site on which Class B bulk sewage sludge is applied.
(L) The following certification statement when the vector attraction reduction requirement in either §503.33(b)(9) or (b)(10) is met:
I certify, under penalty of law, that the information that will be used to determine compliance with the vector attraction reduction requirement in (insert either §503.33(b)(9) or §503.33(b)(10)) was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (M) If the vector attraction reduction requirements in either §503.33 (b)(9) or (b)(10) are met, a description of how the requirements are met.
(6) If the requirements in §503.13(a)(4)(ii) are met when sewage sludge is sold or given away in a bag or other container for application to the land, the person who prepares the sewage sludge that is sold or given away in a bag or other container shall develop the following information and shall retain the information for five years:
(i) The annual whole sludge application rate for the sewage sludge that does not cause the annual pollutant loading rates in Table 4 of §503.13 to be exceeded. (ii) The concentration of each pollutant listed in Table 4 of §503.13 in the sewage sludge. (iii) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the management practice in §503.14(e), the Class A pathogen requirement in §503.32(a), and the vector attraction reduction requirement in (insert one of the vector attraction reduction requirements in §503.33(b)(1) through §503.33(b)(8)) was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment. (iv) A description of how the Class A pathogen requirements in §503.32(a) are met. (v) A description of how one of the vector attraction requirements in §503.33 (b)(1) through (b)(8) is met.
(b) Domestic septage. When domestic septage is applied to agricultural land, forest, or a reclamation site, the person who applies the domestic septage shall develop the following information and shall retain the information for five years:
(1) The location, by either street address or latitude and longitude, of each site on which domestic septage is applied.
(2) The number of acres in each site on which domestic septage is applied. (3) The date domestic septage is applied to each site.
7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 15/16 (4) The nitrogen requirement for the crop or vegetation grown on each site during a 365 day period.
(5) The rate, in gallons per acre per 365 day period, at which domestic septage is applied to each site.
(6) The following certification statement:
I certify, under penalty of law, that the information that will be used to determine compliance with the pathogen requirements (insert either §503.32(c)(1) or §503.32(c)(2)) and the vector attraction reduction requirement in [insert §503.33(b)(9), 503.33(b)(10), or §503.33(b)(12)] was prepared under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate this information. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment.
(7) A description of how the pathogen requirements in either §503.32(c)(1) or (c)(2) are met.
(8) A description of how the vector attraction reduction requirements in §503.33 (b)(9), (b)(10), or (b)(12) are met.
(Approved by the Office of Management and Budget under control number 2040-0157) [58 FR 9387, Feb. 19, 1993, as amended at 64 FR 42569, Aug. 4, 1999] Back to Top
§503.18 Reporting.
(a) Class I sludge management facilities, POTWs (as defined in §501.2 of this chapter) with a design flow rate equal to or greater than one million gallons per day, and POTWs that serve 10,000 people or more shall submit a report on February 19 of each year. As of December 21, 2016 all reports submitted in compliance with this section must be submitted electronically by the operator to EPA when the Regional Administrator is the Director in compliance with this section and 40 CFR part 3 (including, in all cases, subpart D to part 3), 40 CFR 122.22, and 40 CFR part 127. As of December 21, 2020 all reports submitted in compliance with this section must be submitted electronically in compliance with this section and 40 CFR part 3 (including, in all cases, subpart D to part 3), 40 CFR 122.22, and 40 CFR part 127. Part 127 is not intended to undo existing requirements for electronic reporting. Prior to the start dates for electronic reporting (see Table 1 in 40 CFR 127.16), the Director may also require operators to electronically submit annual reports under this section if required to do so by state law.
(1) The information in §503.17(a), except the information in §503.17 (a)(3)(ii), (a)(4)(ii) and in (a)(5)(ii), for the appropriate requirements on February 19 of each year. (2) The information in §503.17(a)(5)(ii)(A) through (a)(5)(ii)(G) on February 19th of each year when 90 percent or more of any of the cumulative pollutant loading rates in Table 2 of §503.13 is reached at a land application site.
7/24/2020 Electronic Code of Federal Regulations (eCFR) https://www.ecfr.gov/cgi-bin/text-idx?SID=329f93cbc6b912757dc170a8a1d3f745&mc=true&node=sp40.32.503.b&rgn=div6 16/16 (Approved by the Office of Management and Budget under control number 2040-0157) [58 FR 9387, Feb. 19, 1993, as amended at 64 FR 42570, Aug. 4, 1999; 80 FR 64157, Oct. 22, 2015]
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Adopted Order: 11/14/2019
CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD
LOS ANGELES REGION
320 West 4th Street, Suite 200, Los Angeles, California 90013 (213) 576-6600 Fax (213) 576-6640
Website for the Los Angeles Region (http://www.waterboards.ca.gov/losangeles/) ORDER R4-2019-0137
NPDES NO. CA0056294
WASTE DISCHARGE REQUIREMENTS
FOR THE CITY OF THOUSAND OAKS
HILL CANYON TREATMENT PLANT
DISCHARGE TO NORTH FORK ARROYO CONEJO VIA OUTFALL 005
The following entity is subject to waste discharge requirements (WDRs) set forth in this Order:
Table 1. Discharger Information
Discharger City of Thousand Oaks (Discharger or Permittee) Name of Facility Hill Canyon Treatment Plant (Hill Canyon TP or Facility) including its associated wastewater collection system and outfalls Facility Address 9600 Santa Rosa Road, Camarillo, CA 93012, Ventura County Table 2. Discharge Location
Discharge
Point
Effluent
Description
Discharge Point
Latitude (North)
Discharge Point
Longitude (West) Receiving Water
005 Tertiary treated
wastewater 34.213201º -118.9211516º North Fork
Arroyo Conejo
Table 3. Administrative Information
This Order was adopted on: November 14, 2019
This Order shall become effective on: January 1, 2020
This Order shall expire on: December 31, 2024
The Discharger shall file a Report of Waste Discharge as an application for reissuance of WDRs in accordance with title 23, California Code of Regulations, and an application for reissuance of a National Pollutant Discharge Elimination System (NPDES) permit no later than:
180 days prior to the
Order expiration
date
The United States Environmental Protection Agency (USEPA) and the California Regional Water Quality Control Board, Los Angeles Region have classified this discharge as follows:
Major
Adopted Order: 11/14/2019
I, Renee Purdy, Executive Officer, do hereby certify that this Order with all attachments is a full, true, and correct copy of the Order adopted by the California Regional Water Quality Control Board, Los Angeles Region, on the date indicated above.
Renee Purdy, Executive Officer
CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019
CONTENTS
I. Facility Information……………………………………………………………………………………… .. 4 II. Findings…………………………………………………………………………………………………… . 4
III. Discharge Prohibitions…………………………………………………………………………………… 5 IV. Effluent Limitations and Discharge Specifications…………………………………………………… . 5 A. Effluent Limitations – Discharge Point 005………………………………………… … … … … … 5
1. Final Effluent Limitations – Discharge Point 005…………………………… … … … … … 5
2. Interim Effluent Limitations………………………………………………………………… . 9 B. Land Discharge Specifications – Not Applicable……………………………………………… . 10 C. Recycling Specifications………………………………………………………………………… . 10 V. Receiving Water Limitations…………………………………………………………………………… 10 A. Surface Water Limitations……………………………………………………………………… . 10 B. Groundwater Limitations………………………………………………………………………… 12 VI. Provisions………………………………………………………………………………………………… 13 A. Standard Provisions……………………………………………………………………………… 13 B. Monitoring and Reporting Program (MRP) Requirements…………………………………… 16 C. Special Provisions……………………………………………… ……………………………… . 16
1. Reopener Provisions……………………………………………………………………… 16
2. Special Studies, Technical Reports and Additional Monitoring Requirements……… 18
3. Best Management Practices and Pollution Prevention………………………………… 19
4. Construction, Operation and Maintenance Specifications…………………………… . 21
5. Special Provisions for Municipal Facilities (POTWs Only) …………………………… 21
6. Spill Reporting Requirements…………………………………………………………… . 23
7. Compliance Schedules – Not Applicable………………………………………… ……. 27 VII. Compliance Determination……………………………………………………………… …………… 27 TABLES
Table 1. Discharger Information……………………………………………………………………………… 1 Table 2. Discharge Location………………………………………………………………………………… . 1 Table 3. Administrative Information………………………………………………………………………… . 1 Table 4. Effluent Limitations………………………………………………………………………………… . 5 Table 5. Radioactivity Effluent Limitations……………………………………………………………… … . 8
ATTACHMENTS
Attachment A – Definitions………………………………………………………………………………… . A-1 Attachment B-1 – Vicinity Map…………………………………………………………………………… ... B-1 Attachment B-2 – Map of Hill Canyon TP………………………………………………………………… B-2 Attachment C – Flow Schematic…………………………………………………………………………… C-1 Attachment D – Standard Provisions……………………………………………………………………… D-1 Attachment E – Monitoring and Reporting Program…………………………………………………… … E-1 Attachment F – Fact Sheet………………………………………………………………………………… F-1 Attachment G – Toxicity Reduction Evaluation (TRE) Work Plan……………………………………… G-1 Attachment H – Biosolids and Sludge Management…………………………………………………… . H-1 Attachment I – Pretreatment Reporting Requirements………………………………………………… . I-1
FIGURES
Figure E-1. Hill Canyon TP Receiving Water Stations………………………………………………… . E-6 THE CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019 4
I. FACILITY INFORMATION
Information describing the Hill Canyon Treatment Plant (Hill Canyon TP or Facility) is summarized in Table 1 and in sections I and II of the Fact Sheet (Attachment F). Section I of the Fact Sheet also includes information regarding the Facility’s permit application.
II. FINDINGS
The California Regional Water Quality Control Board, Los Angeles Region (Regional Water Board), finds:
A. Legal Authorities. This Order serves as waste discharge requirements (WDRs) pursuant to article 4, chapter 4, division 7 of the California Water Code (CWC) (commencing with section 13260).This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the U.S.
EPA and chapter 5.5, division 7 of the Water Code (commencing with section 13370).
It shall serve as a National Pollutant Discharge Elimination System (NPDES) permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 2 subject to the WDRs in this Order.
B. Background and Rationale for Requirements. The Regional Water Board developed the requirements in this Order based on information submitted as part of the application, through monitoring and reporting programs, and other available information. The Fact Sheet (Attachment F), which contains background information and rationale for the requirements in this Order, is hereby incorporated into and constitutes Findings for this Order. Attachments A through E and G through I are also incorporated into this Order.
C. Provisions and Requirements Implementing State Law. The provisions/requirements in subsection IV.B, IV.C, and V.B are included to implement state law only.
D. Notification of Interested Parties. The Regional Water Board has notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and has provided them with an opportunity to submit their written comments and recommendations. Details of the notification are provided in the Fact Sheet.
E. Consideration of Public Comment. The Regional Water Board, in a public meeting, heard and considered all comments pertaining to the discharge. Details of the Public Hearing are provided in the Fact Sheet.
THEREFORE, IT IS HEREBY ORDERED that this Order supersedes Order R4-2014- 0064-A02 except for enforcement purposes, and, in order to meet the provisions contained in Division 7 of the CWC (commencing with section 13000) and regulations adopted thereunder, and the provisions of the CWA and regulations and guidelines adopted thereunder, the Permittee is authorized to discharge from the identified facility and outfalls into waters of the United States and shall comply with the requirements in this Order. This action in no way prevents the Regional Water Board from taking enforcement action for past violations of the previous Order.
THE CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019 5
III. DISCHARGE PROHIBITIONS
A. Discharge of treated wastewater at a location different from that described in this Order is prohibited.
B. The bypass or overflow of untreated wastewater or wastes to surface waters or surface water drainage courses is prohibited, except as allowed in Standard Provision I.G. of Attachment D, Standard Provisions.
C. The monthly average effluent dry weather discharge flow rate from the facility shall not exceed the 14 million gallons per day (MGD) design capacity.
D. The Permittee shall not cause degradation of any water supply, except as consistent with State Water Board Resolution No. 68-16.
E. The treatment or disposal of wastes from the facility shall not cause pollution or nuisance as defined in section 13050, subdivisions (l) and (m), of the CWC.
F. The discharge of any substances in concentrations toxic to animal or plant is prohibited.
G. The discharge of any radiological, chemical, or biological warfare agent or high level radiological waste is prohibited.
IV. EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS
A. Effluent Limitations – Discharge Point 005
1. Final Effluent Limitations – Discharge Point 005
a. The Permittee shall maintain compliance with the following effluent limitations at Discharge Point 005, into North Fork Arroyo Conejo, with compliance measured at Monitoring Location EFF-005 as described in the Monitoring and Reporting Program (MRP), Attachment E:
Table 4. Effluent Limitations
Parameters Units Average
Monthly
Average
Weekly
Maximum
Daily
Biochemical Oxygen
Demand (BOD520°C) mg/L 20 30 45
BOD520°C lbs/day 2,300 3,500 5,200
Total Suspended Solids
(TSS) mg/L 15 40 45
TSS lbs/day 1,750 4,600 5,200
Temperature °F -- -- 86
Removal Efficiency for BOD % ≥85 -- --
Removal Efficiency for TSS % ≥85 -- --
Oil and Grease mg/L 10 -- 15
THE CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019 6
Parameters Units Average
Monthly
Average
Weekly
Maximum
Daily
Oil and Grease lbs/day 1,200 -- 1,750
Settleable Solids ml/L 0.1 -- 0.3
Total Residual Chlorine mg/L -- -- 0.1
Total Dissolved Solids
(TDS) (dry-weather) lbs/day 99,250 -- --
TDS (wet-weather) mg/L 850 -- --
Sulfate (dry-weather) lbs/day 29,200 -- --
Sulfate (wet-weather) mg/L 250 -- --
Chloride (dry-weather) lbs/day 17,500 -- --
Chloride (wet-weather) mg/L 150 -- --
Boron (dry-weather) lbs/day 120 -- --
Boron (wet-weather) mg/l 1.0 -- --
MBAS mg/L 0.5 -- --
MBAS lbs/day 60 -- --
Ammonia Nitrogen mg/L 3.1 -- 5.6
Ammonia Nitrogen lbs/day -- -- 5.1 x Q1
Nitrate + Nitrite (as N) mg/L 9 -- --
Nitrate (as N) mg/L 9 -- --
Nitrite (as N) mg/L 0.9 -- --
Copper µg/L 6 -- 9
Copper lbs/day -- -- 0.7
Nickel µg/L 153 -- 231
Nickel lbs/day -- -- 0.3
Mercury lbs/month 0.022 -- --
Cyanide µg/L 4.2 -- 8.5
Cyanide lbs/day 0.49 -- 0.99
Bis (2-Ethylhexyl) Phthalate µg/L 4 -- --
Bis (2-Ethylhexyl) Phthalate lbs/day 0.46 -- --
1 Q represents the POTW effluent flow at the time the water quality measurement is collected (not to exceed the design flow of 14 mgd) and a conversion factor to lbs/day based on the units of measure for the flow.
THE CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019 7
Parameters Units Average
Monthly
Average
Weekly
Maximum
Daily
Chlorpyrifos µg/L 0.014 -- 0.025
Diazinon µg/L 0.1 -- 0.1
Chronic Toxicity2, 3
Pass or Fail,
% Effect
(Test of
Significant
Toxicity,
(TST))
Pass4 -- Pass or
% Effect <50
Chlordane µg/L 0.00059 -- 0.0012
4,4’-DDD µg/L 0.00084 -- 0.0017
4,4’-DDE µg/L 0.00059 -- 0.0012
4,4’-DDT µg/L 0.00059 -- 0.0012
Dieldrin µg/L 0.00014 -- 0.00028
PCBs µg/L 0.00017 -- 0.00034
Toxaphene µg/L 0.00016 -- 0.00033
2 The Median Monthly Effluent Limitation (MMEL) shall be reported as “Pass” or “Fail.” The Maximum Daily Effluent Limitation (MDEL) shall be reported as “Pass” or “Fail” and “% Effect.” The MMEL for chronic toxicity shall only apply when there is a discharge on more than one day in a calendar month period.
During such calendar months, up to three independent toxicity tests may be conducted when one toxicity test results in “Fail.”
3 The Calleguas Creek Watershed Toxicity TMDL includes a WLA of 1.0 TUc for toxicity, which is required to be implemented in accordance with USEPA, State Water Board, and Regional Water Board resolutions, guidance and policy at the time of permit issuance or renewal. In addition, a numeric water quality-based effluent limitation (WQBEL) is established because effluent data showed that there is reasonable potential for the effluent to cause or contribute to an exceedance of the chronic toxicity water quality objective. The numeric WLA is protective of both the numeric acute toxicity and the narrative toxicity Basin Plan water quality objectives. Consistent with the Toxicity TMDL, these chronic toxicity WLA-based final effluent limitations shall be implemented using the Short Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (U.S. EPA 2002, EPA- 821-R-02-013), and current USEPA guidance in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, June /2010) EPA Regions 8, 9, and 10 Toxicity Training Tool (January 2010)
(https://www.epa.gov/sites/production/files/documents/ToxTrainingTool10Jan2010.pdf). 4 This is a Median Monthly Effluent Limitation.
THE CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019 8
Table 5. Radioactivity Effluent Limitations
Parameters Units Average
Monthly
Average
Weekly
Maximum
Daily
Combined Radium-226 and
Radium 228
Pico Curies
per liter
(pCi/L)
5 -- --
Gross Alpha particle activity
(excluding radon and
uranium)
pCi/L 15 -- --
Uranium pCi/L 20 -- --
Gross Beta/photon emitters millirem/
year 4 -- --
Strontium-90 pCi/L 8 -- --
Tritium pCi/L 20,000 -- --
b. The mass based effluent limitations are based on the plant design flow rate of 14 mgd and are calculated as follows: Flow (MGD) x Concentration (mg/L) x 8.34 (conversion factor) = lbs/day. During wet-weather storm events in which the flow exceeds the design capacity, the mass discharge rate limitations shall not apply, and concentration limitations shall be the only applicable effluent limitations.
c. The effluent values for pH shall be maintained within the limits of 6.5 standard units and 8.5 standard units.
d. The wastes discharged to water courses shall at all times be adequately disinfected. For the purpose of this requirement, the wastes shall be considered adequately disinfected if: (1) the median number of total coliform bacteria at some point in the treatment process does not exceed a 7-day median of 2.2 Most Probable Number (MPN) or Colony Forming Unit (CFU) per 100 milliliters utilizing the bacteriological results of the last seven (7) days for which an analysis has been completed, (2) the number of total coliform bacteria does not exceed 23 MPN or CFU per 100 milliliters in more than one sample within any 30-day period, and (3) no sample shall exceed 240 MPN or CFU of total coliform bacteria per 100 milliliters. Samples shall be collected at a time when wastewater flow and characteristics are most demanding on treatment facilities and disinfection processes. e. For the protection of the water contact recreation beneficial use, the wastes discharged to water courses shall have received adequate treatment, so that the turbidity of the treated wastewater does not exceed any of the following:
(a) an average of 2 Nephelometric turbidity units (NTU) within a 24-hour period, (b) 5 NTU more than 5 percent of the time (72 minutes) within a 24- hour period, and (c) 10 NTU at any time.
THE CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019 9
f. For TDS, sulfate, chloride, and boron discharges during wet- and dry- weather; dry-weather is defined in the Calleguas Creek Watershed Salts Total Maximum Daily Load (Salts TMDL) as the condition when the flows in the receiving water are below the 86th percentile flow. Wet-weather is defined in the Salts TMDL as the condition when the flows in the receiving water are greater than or equal to the 86th percentile flow. These are explained in section VII.O of this Order.
g. To protect the existing beneficial use of groundwater recharge (GWR) and the underlying ground water basins, pollutants shall not be present in the wastes discharged at concentrations that pose a threat to ground water quality.
2. Interim Effluent Limitations
a. Metals TMDL-based Interim limits: As of December 31, 2017, the effluent from the Hill Canyon TP has consistently achieved the final waste load allocations for the Metals TMDL. Therefore, no interim effluent limitations are included in this Order for these pollutants and only the final effluent limitations for these pollutants are applicable in this Order. b. Organo Chlorine Pesticides, PCBs, and Siltation TMDL-based Interim limits: Interim WLAs are included in the OC Pesticides, PCBs, and Siltation TMDL for chlordane, 4,4’-DDD, 4,4’-DDE, 4,4’-DDT, dieldrin, PCBs, and toxaphene applicable to Hill Canyon TP effluent discharge. However, existing data indicate that the facility is consistently meeting the final effluent limitations for the aforementioned parameters. Therefore, the interim effluent limitations are not warranted and only the final effluent limitations for these pollutants are applicable in this Order.
c. Boron, Chloride, Sulfate, and TDS (Salts) TMDL-based Interim limits:
The interim effluent limitations for salts are derived from the interim WLAs as set forth in the Calleguas Creek Watershed Salts TMDL (Salts TMDL), established by the Regional Water Board on October 4, 2007, which became effective on December 8, 2008. The TMDL interim effluent limitation are set equal to the 95th percentile of available discharge data. There is no interim effluent limitation for boron because the 95th percentile concentration is below the Basin Plan objective. TDS, sulfate, and chloride data indicate that the facility is complying with the Basin Plan water quality objectives (WQOs).
Therefore, the interim effluent limitations for TDS, sulfate, chloride, and boron are not warranted and only the final effluent limitations for TDS, sulfate, chloride, and boron are applicable in this Order. d. Toxicity, Chlorpyrifos, and Diazinon TMDL-based Interim limits: The interim effluent limitations for toxicity, chlorpyrifos, and diazinon, contained in the Calleguas Creek TMDL for Toxicity, Chlorpyrifos, and Diazinon, are no longer applicable because they expired on March 24, 2008. Therefore, no interim effluent limitations are included in this Order for these pollutants and only the final effluent limitations for these pollutants are applicable in this Order.
THE CITY OF THOUSAND OAKS ORDER R4-2019-0137
HILL CANYON TREATMENT PLANT NPDES NO. CA0056294
Adopted Order: 11/14/2019 10
e. Nitrogen Compounds TMDL-based Interim limits: The interim effluent limitations are no longer applicable because the implementation plan of the Nitrogen Compounds TMDL required POTWs to achieve compliance with the final WLAs for nitrate-N, nitrite-N, and nitrate plus nitrite as nitrogen by October 15, 2013 and the WLA for ammonia-N by October 15, 2016.
Therefore, no interim effluent limitations are included in this Order for these pollutants and only the final effluent limitations for these pollutants are applicable in this Order.
B. Land Discharge Specifications – Not Applicable
C. Recycling Specifications
The Discharger captures and treats storm water on the premises through its wastewater treatment plant and recycles tertiary treated water through a separate Order, Board Order No. R4-2013-0140, adopted on September 12, 2013. During the next permit term, the Permittee shall continue to investigate the feasibility of increasing the amount of recycling, conservation, and/or alternative disposal methods for wastewater (such as groundwater injection), and/or beneficial use of storm water and dry-weather urban runoff and submit an update to this feasibility study as part of the submittal of the Report of Waste Discharge (ROWD) for the next permit renewal.
No additional recycling specifications are included in this Order.
V. RECEIVING WATER LIMITATIONS
A. Surface Water Limitations
Receiving water limitations are based on water quality objectives contained in the Basin Plan and are a required part of this Order. The discharge shall not cause the following in the receiving water:
1. The natural receiving water temperature of all regional waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses.
Alterations that are allowed must meet the following requirements at the receiving water point of compliance, North Fork Arroyo Conejo: For waters designated with a warm freshwater habitat (WARM) beneficial use, water temperature shall not be altered by more than 5°F above the natural temperature. At no time shall these WARM-designated waters be raised above 80°F as a result of waste discharge.
2. The pH of inland surface waters shall not be depressed below 6.5 or raised above 8.5 as a result of wastes discharged. Ambient pH levels shall not be changed more than 0.5 units from natural conditions as a result of wastes discharged. Natural conditions shall be determined on a case-by-case basis.
3. The dissolved oxygen in the receiving water shall not be depressed below 5 mg/L as a result of the wastes discharged.
4. The total residual chlorine shall not exceed 0.1 mg/L in the receiving waters and shall not persist in the receiving water at any concentration that causes impairment of beneficial uses as a result of the wastes discharged.
APPENDIX D
Local Limits Data Summary
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
06/01/19 8.60 8.45
06/02/19 8.66 8.29
06/03/19 8.68 8.49
06/04/19 8.69 8.46
06/05/19 8.82 8.66
06/06/19 8.77 8.38
06/07/19 8.73 8.67
06/08/19 8.69 8.44
06/09/19 8.68 8.41
06/10/19 8.80 8.59
06/11/19 8.69 8.42
06/12/19 8.68 8.50
06/13/19 8.05 8.28
06/14/19 8.82 8.64
06/15/19 8.61 8.30
06/16/19 8.70 8.33
06/17/19 8.73 8.45
06/18/19 8.84 8.24
06/19/19 8.83 8.40
06/20/19 8.71 8.35
06/21/19 8.64 8.31
06/22/19 8.69 8.35
06/23/19 8.68 8.44
06/24/19 8.72 8.50
06/25/19 8.59 8.17
06/26/19 8.60 8.28
06/27/19 8.56 8.27
06/28/19 8.78 8.25
06/29/19 8.50 8.28
06/30/19 8.47 8.12
07/01/19 8.61 8.25
07/02/19 8.46 8.09
07/03/19 8.39 8.04
07/04/19 8.15 7.81
07/05/19 8.26 8.05
07/06/19 8.30 7.65
07/07/19 8.59 8.31
07/08/19 8.60 8.21
07/09/19 8.45 7.99
07/10/19 8.52 8.22
07/11/19 8.52 8.03
07/12/19 8.73 8.40
07/13/19 8.60 8.16
07/14/19 8.53 8.12
07/15/19 8.64 8.26
City of Thousand Oaks
Hill Canyon Treatment Plant D-1 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
07/16/19 8.70 8.20
07/17/19 8.69 8.36
07/18/19 8.58 8.09
07/19/19 8.57 8.23
07/20/19 8.38 7.91
07/21/19 8.46 8.20
07/22/19 8.73 8.21
07/23/19 8.76 8.28
07/24/19 8.73 8.25
07/25/19 8.77 8.18
07/26/19 8.78 8.34
07/27/19 8.57 8.15
07/28/19 8.68 8.19
07/29/19 8.74 8.43
07/30/19 8.65 8.24
07/31/19 8.74 8.08
08/01/19 8.56 8.56
08/02/19 8.51 8.51
08/03/19 8.57 8.57
08/04/19 8.51 8.51
08/05/19 8.55 8.55
08/06/19 8.62 8.62
08/07/19 8.66 8.66
08/08/19 8.52 8.52
08/09/19 8.61 8.61
08/10/19 8.37 8.37
08/11/19 8.46 8.46
08/12/19 8.57 8.57
08/13/19 8.48 8.48
08/14/19 8.47 8.47
08/15/19 8.50 8.50
08/16/19 8.46 8.46
08/17/19 8.43 8.43
08/18/19 8.54 8.54
08/19/19 8.65 8.65
08/20/19 8.74 8.74
08/21/19 8.67 8.67
08/22/19 8.61 8.61
08/23/19 8.56 8.56
08/24/19 8.64 8.64
08/25/19 8.75 8.75
08/26/19 8.66 8.66
08/27/19 8.69 8.69
08/28/19 8.64 8.64
08/29/19 8.61 8.61
City of Thousand Oaks
Hill Canyon Treatment Plant D-2 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
08/30/19 8.57 8.57
08/31/19 8.44 8.44
09/01/19 8.28 7.69
09/02/19 8.93 7.73
09/03/19 8.75 7.71
09/04/19 8.73 9.33
09/05/19 8.65 8.56
09/06/19 8.66 8.31
09/07/19 8.57 8.36
09/08/19 8.70 8.30
09/09/19 8.80 8.13
09/10/19 8.53 8.18
09/11/19 8.50 8.44
09/12/19 8.52 8.06
09/13/19 8.57 8.27
09/14/19 8.48 8.17
09/15/19 8.66 8.36
09/16/19 8.56 7.75
09/17/19 8.54 8.07
09/18/19 8.45 8.30
09/19/19 8.44 8.18
09/20/19 8.47 8.17
09/21/19 8.37 8.03
09/22/19 8.53 8.05
09/23/19 8.59 8.13
09/24/19 8.47 7.95
09/25/19 8.51 8.15
09/26/19 8.64 8.37
09/27/19 8.40 7.98
09/28/19 8.33 8.16
09/29/19 8.52 8.09
09/30/19 8.66 8.17
10/01/19 8.57 8.22
10/02/19 8.44 8.02
10/03/19 8.41 8.08
10/04/19 8.40 7.92
10/05/19 8.41 8.25
10/06/19 8.54 8.10
10/07/19 8.48 8.19
10/08/19 8.46 8.10
10/09/19 8.59 8.31
10/10/19 8.37 7.96
10/11/19 8.27 7.97
10/12/19 8.31 7.81
10/13/19 8.48 8.15
City of Thousand Oaks
Hill Canyon Treatment Plant D-3 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
10/14/19 8.55 8.23
10/15/19 8.56 8.06
10/16/19 8.40 8.09
10/17/19 8.45 8.06
10/18/19 8.38 8.05
10/19/19 8.30 7.84
10/20/19 8.54 8.25
10/21/19 8.39 7.99
10/22/19 8.35 7.95
10/23/19 8.42 7.98
10/24/19 8.39 8.04
10/25/19 8.29 7.61
10/26/19 8.38 8.06
10/27/19 8.55 8.33
10/28/19 8.45 8.00
10/29/19 8.46 8.20
10/30/19 7.96 7.82
10/31/19 8.14 7.59
11/01/19 8.39 7.99
11/02/19 8.33 8.04
11/03/19 8.44 8.11
11/04/19 8.38 8.05
11/05/19 8.22 7.98
11/06/19 8.01 7.94
11/07/19 8.31 8.06
11/08/19 8.23 7.85
11/09/19 8.24 7.95
11/10/19 8.32 7.91
11/11/19 8.56 8.30
11/12/19 8.30 7.97
11/13/19 8.38 8.10
11/14/19 8.29 7.77
11/15/19 8.33 8.29
11/16/19 8.42 8.00
11/17/19 8.56 8.22
11/18/19 8.64 8.25
11/19/19 8.32 8.05
11/20/19 7.91 7.48
11/21/19 8.41 8.05
11/22/19 8.36 8.25
11/23/19 8.41 7.95
11/24/19 8.32 8.23
11/25/19 8.40 7.94
11/26/19 8.43 8.31
11/27/19 8.93 8.38
City of Thousand Oaks
Hill Canyon Treatment Plant D-4 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
11/28/19 9.66 9.47
11/29/19 8.85 8.73
11/30/19 8.61 8.24
12/01/19 9.15 8.68
12/02/19 8.69 8.26
12/03/19 8.49 8.16
12/04/19 10.23 10.32
12/05/19 9.03 8.51
12/06/19 8.70 8.48
12/07/19 8.98 8.46
12/08/19 9.25 9.13
12/09/19 8.93 8.47
12/10/19 8.86 8.48
12/11/19 8.74 8.43
12/12/19 8.79 8.33
12/13/19 8.81 8.62
12/14/19 8.79 8.35
12/15/19 8.90 8.49
12/16/19 8.76 8.49
12/17/19 8.69 8.26
12/18/19 8.66 8.17
12/19/19 8.75 8.47
12/20/19 8.60 8.49
12/21/19 8.78 8.25
12/22/19 9.54 9.19
12/23/19 9.92 9.94
12/24/19 9.50 9.34
12/25/19 9.36 9.00
12/26/19 11.50 11.64
12/27/19 9.68 9.37
12/28/19 9.14 8.81
12/29/19 8.84 8.66
12/30/19 8.90 8.56
12/31/19 9.08 8.63
01/01/20 8.61 8.39
01/02/20 8.81 8.35
01/03/20 8.87 8.55
01/04/20 8.85 8.91
01/05/20 9.24 8.45
01/06/20 8.91 8.31
01/07/20 8.75 8.44
01/08/20 8.78 8.28
01/09/20 8.81 8.55
01/10/20 8.66 8.44
01/11/20 8.79 8.30
City of Thousand Oaks
Hill Canyon Treatment Plant D-5 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
01/12/20 9.04 8.76
01/13/20 8.76 8.40
01/14/20 8.74 8.33
01/15/20 8.70 8.24
01/16/20 8.67 8.35
01/17/20 8.76 8.42
01/18/20 8.83 8.47
01/19/20 8.70 8.37
01/20/20 9.01 8.54
01/21/20 8.77 8.30
01/22/20 8.74 8.34
01/23/20 8.76 8.27
01/24/20 8.76 8.42
01/25/20 8.74 8.20
01/26/20 8.83 8.57
01/27/20 8.81 8.27
01/28/20 8.70 8.36
01/29/20 8.70 8.20
01/30/20 8.72 8.38
01/31/20 8.60 8.01
02/01/20 8.86 8.36
02/02/20 9.01 8.54
02/03/20 8.72 8.35
02/04/20 8.53 8.19
02/05/20 8.36 8.35
02/06/20 8.56 8.19
02/07/20 8.73 8.40
02/08/20 8.82 8.29
02/09/20 8.92 8.65
02/10/20 8.77 8.26
02/11/20 8.71 8.35
02/12/20 8.69 8.66
02/13/20 8.54 8.11
02/14/20 8.74 9.03
02/15/20 8.63 8.18
02/16/20 8.57 9.10
02/17/20 9.12 8.38
02/18/20 8.83 8.08
02/19/20 8.74 8.17
02/20/20 8.73 7.88
02/21/20 8.70 8.10
02/22/20 8.74 7.98
02/23/20 8.93 8.31
02/24/20 8.66 8.05
02/25/20 8.48 7.69
City of Thousand Oaks
Hill Canyon Treatment Plant D-6 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
02/26/20 8.57 8.01
02/27/20 8.61 7.69
02/28/20 8.55 7.95
02/29/20 8.73 7.85
03/01/20 8.87 8.31
03/02/20 8.69 7.93
03/03/20 8.68 8.03
03/04/20 8.63 7.89
03/05/20 8.62 8.15
03/06/20 8.81 8.02
03/07/20 8.64 7.95
03/08/20 9.00 8.42
03/09/20 8.73 8.12
03/10/20 8.73 8.15
03/11/20 8.84 8.18
03/12/20 9.41 8.70
03/13/20 10.22 10.06
03/14/20 9.49 8.75
03/15/20 9.45 9.43
03/16/20 10.45 9.22
03/17/20 9.91 9.05
03/18/20 9.53 8.81
03/19/20 9.22 8.12
03/20/20 9.10 10.38
03/21/20 9.22 8.32
03/22/20 9.48 9.40
03/23/20 9.58 9.30
03/24/20 9.23 8.79
03/25/20 9.11 8.58
03/26/20 9.00 8.51
03/27/20 8.90 8.30
03/28/20 9.01 8.47
03/29/20 9.03 8.39
03/30/20 8.91 8.33
03/31/20 8.87 8.34
04/01/20 8.84 8.36
04/02/20 8.81 8.19
04/03/20 8.81 8.27
04/04/20 8.85 8.22
04/05/20 8.86 8.49
04/06/20 9.63 9.12
04/07/20 9.14 8.94
04/08/20 9.28 9.09
04/09/20 10.07 9.32
04/10/20 10.12 10.09
City of Thousand Oaks
Hill Canyon Treatment Plant D-7 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
04/11/20 9.95 9.47
04/12/20 9.47 8.52
04/13/20 9.42 8.90
04/14/20 9.30 8.59
04/15/20 9.16 8.47
04/16/20 9.11 8.52
04/17/20 9.15 8.39
04/18/20 9.08 8.43
04/19/20 9.14 8.47
04/20/20 9.02 8.53
04/21/20 8.94 8.09
04/22/20 8.99 8.29
04/23/20 9.03 8.29
04/24/20 9.09 8.23
04/25/20 9.14 8.22
04/26/20 9.29 8.61
04/27/20 9.08 8.39
04/28/20 8.96 8.23
04/29/20 9.05 8.38
04/30/20 8.82 8.36
05/01/20 8.55 8.26
05/02/20 8.57 8.48
05/03/20 8.55 8.33
05/04/20 8.38 8.40
05/05/20 8.45 8.01
05/06/20 8.48 8.05
05/07/20 8.35 8.07
05/08/20 8.44 8.73
05/09/20 8.53 8.66
05/10/20 8.31 8.94
05/11/20 8.44 8.63
05/12/20 8.33 8.57
05/13/20 8.39 8.78
05/14/20 8.41 8.58
05/15/20 8.51 8.72
05/16/20 8.44 8.81
05/17/20 8.57 8.73
05/18/20 8.46 8.89
05/19/20 8.45 8.56
05/20/20 8.36 8.63
05/21/20 8.53 8.57
05/22/20 8.98 9.03
05/23/20 8.60 8.73
05/24/20 8.58 8.55
05/25/20 8.77 8.89
City of Thousand Oaks
Hill Canyon Treatment Plant D-8 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
05/26/20 8.32 8.11
05/27/20 8.67 8.77
05/28/20 8.60 8.48
05/29/20 8.79 8.90
05/30/20 8.65 8.91
05/31/20 8.71 8.74
06/01/20 8.71 8.89
06/02/20 8.64 8.60
06/03/20 8.68 8.75
06/04/20 8.81 8.70
06/05/20 8.55 8.83
06/06/20 8.58 8.85
06/07/20 8.62 8.39
06/08/20 8.51 8.84
06/09/20 8.49 9.08
06/10/20 8.64 9.15
06/11/20 8.68 8.73
06/12/20 8.82 8.82
06/13/20 8.60 8.70
06/14/20 8.60 8.69
06/15/20 8.67 8.75
06/16/20 8.61 8.64
06/17/20 8.62 8.69
06/18/20 8.60 8.78
06/19/20 8.63 8.53
06/20/20 8.57 8.77
06/21/20 8.63 8.80
06/22/20 8.81 9.09
06/23/20 8.86 8.59
06/24/20 8.66 8.91
06/25/20 8.69 8.67
06/26/20 8.84 8.94
06/27/20 8.60 8.77
06/28/20 8.63 8.82
06/29/20 8.86 8.79
06/30/20 8.58 8.69
07/01/20 8.59 8.68
07/02/20 8.48 8.61
07/03/20 8.52 8.49
07/04/20 8.28 8.47
07/05/20 8.40 8.38
07/06/20 8.70 8.86
07/07/20 8.50 8.41
07/08/20 8.52 8.62
07/09/20 8.47 8.56
City of Thousand Oaks
Hill Canyon Treatment Plant D-9 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
07/10/20 8.74 8.91
07/11/20 8.49 8.54
07/12/20 8.53 8.71
07/13/20 8.74 8.62
07/14/20 8.53 8.66
07/15/20 8.44 8.40
07/16/20 8.47 8.73
07/17/20 8.45 8.44
07/18/20 8.36 8.55
07/19/20 8.51 8.42
07/20/20 8.58 8.70
07/21/20 8.44 8.47
07/22/20 8.38 8.35
07/23/20 8.29 7.88
07/24/20 8.46 8.56
07/25/20 8.39 8.46
07/26/20 8.41 8.65
07/27/20 8.41 8.43
07/28/20 8.33 8.47
07/29/20 8.39 8.38
07/30/20 8.44 8.47
07/31/20 8.48 8.58
08/01/20 8.44 8.36
08/02/20 8.57 8.70
08/03/20 8.54 8.56
08/04/20 8.86 8.87
08/05/20 9.47 9.67
08/06/20 9.49 9.58
08/07/20 9.49 9.46
08/08/20 9.46 9.63
08/09/20 9.62 9.41
08/10/20 9.61 10.04
08/11/20 9.52 9.63
08/12/20 9.52 9.60
08/13/20 9.47 9.39
08/14/20 9.51 9.63
08/15/20 9.67 9.32
08/16/20 9.87 9.81
08/17/20 9.81 10.06
08/18/20 9.66 9.93
08/19/20 9.85 9.84
08/20/20 9.82 9.58
08/21/20 9.84 10.03
08/22/20 9.72 9.72
08/23/20 9.93 9.93
City of Thousand Oaks
Hill Canyon Treatment Plant D-10 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
08/24/20 9.91 10.16
08/25/20 9.77 9.79
08/26/20 9.72 9.89
08/27/20 9.69 9.58
08/28/20 9.51 9.90
08/29/20 9.46 8.80
08/30/20 9.64 10.22
08/31/20 9.52 9.59
09/01/20 9.52 9.84
09/02/20 9.56 9.53
09/03/20 9.57 9.71
09/04/20 9.65 9.52
09/05/20 9.51 9.56
09/06/20 9.38 9.22
09/07/20 9.88 9.61
09/08/20 9.88 10.03
09/09/20 9.61 9.58
09/10/20 9.50 9.52
09/11/20 9.45 8.50
09/12/20 9.44 9.22
09/13/20 9.57 9.63
09/14/20 9.54 9.55
09/15/20 9.45 10.11
09/16/20 9.39 9.96
09/17/20 9.49 9.86
09/18/20 9.20 9.59
09/19/20 8.45 8.21
09/20/20 8.39 8.75
09/21/20 9.02 8.77
09/22/20 9.42 9.70
09/23/20 9.39 9.23
09/24/20 9.41 9.27
09/25/20 9.33 8.22
09/26/20 9.40 8.65
09/27/20 9.45 9.99
09/28/20 9.52 9.90
09/29/20 9.47 9.85
09/30/20 9.41 8.98
10/01/20 9.54 9.61
10/02/20 9.49 9.42
10/03/20 9.34 9.30
10/04/20 9.60 9.37
10/05/20 9.62 9.78
10/06/20 9.48 9.31
10/07/20 9.38 9.48
City of Thousand Oaks
Hill Canyon Treatment Plant D-11 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
10/08/20 9.35 9.23
10/09/20 9.39 9.67
10/10/20 9.46 9.17
10/11/20 9.58 9.90
10/12/20 9.54 9.34
10/13/20 9.42 9.49
10/14/20 9.47 9.26
10/15/20 9.38 9.37
10/16/20 9.34 9.05
10/17/20 9.35 9.38
10/18/20 9.55 9.67
10/19/20 9.59 9.50
10/20/20 9.52 9.68
10/21/20 9.64 9.51
10/22/20 9.54 9.62
10/23/20 9.47 9.51
10/24/20 9.46 9.33
10/25/20 9.57 9.94
10/26/20 9.46 9.60
10/27/20 9.24 9.08
10/28/20 9.48 9.18
10/29/20 9.51 9.06
10/30/20 9.51 9.54
10/31/20 9.47 9.07
11/01/20 9.61 9.72
11/02/20 9.18 8.96
11/03/20 8.94 8.64
11/04/20 9.46 9.32
11/05/20 9.41 9.03
11/06/20 9.38 9.42
11/07/20 9.33 9.42
11/08/20 9.48 9.50
11/09/20 9.54 9.17
11/10/20 9.49 9.56
11/11/20 9.45 9.42
11/12/20 9.45 9.38
11/13/20 9.18 9.22
11/14/20 7.85 8.19
11/15/20 9.59 9.70
11/16/20 9.54 9.12
11/17/20 9.32 9.37
11/18/20 9.39 9.14
11/19/20 9.37 9.64
11/20/20 9.47 9.58
11/21/20 9.44 9.36
City of Thousand Oaks
Hill Canyon Treatment Plant D-12 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
11/22/20 9.46 9.44
11/23/20 9.39 9.47
11/24/20 9.40 9.36
11/25/20 9.53 9.38
11/26/20 9.72 9.73
11/27/20 9.30 9.35
11/28/20 9.37 9.43
11/29/20 9.52 9.29
11/30/20 9.60 9.64
12/01/20 9.53 9.30
12/02/20 9.56 9.59
12/03/20 9.34 9.08
12/04/20 9.34 9.32
12/05/20 9.38 9.08
12/06/20 9.54 9.70
12/07/20 9.39 9.31
12/08/20 9.34 9.15
12/09/20 9.38 9.11
12/10/20 9.30 9.27
12/11/20 9.31 9.16
12/12/20 9.39 9.36
12/13/20 9.58 9.62
12/14/20 9.28 9.30
12/15/20 9.26 9.09
12/16/20 9.42 9.18
12/17/20 9.34 9.42
12/18/20 9.33 9.07
12/19/20 9.38 9.00
12/20/20 9.42 9.37
12/21/20 9.33 9.13
12/22/20 9.28 9.14
12/23/20 9.36 9.15
12/24/20 9.60 9.28
12/25/20 9.08 9.33
12/26/20 9.41 9.22
12/27/20 9.35 9.37
12/28/20 10.22 10.51
12/29/20 9.57 9.46
12/30/20 9.42 9.28
12/31/20 9.56 9.60
01/01/21 9.47 9.52
01/02/21 9.63 9.48
01/03/21 9.90 10.08
01/04/21 9.61 9.52
01/05/21 9.45 9.33
City of Thousand Oaks
Hill Canyon Treatment Plant D-13 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
01/06/21 9.28 9.25
01/07/21 9.30 9.09
01/08/21 9.28 9.31
01/09/21 9.41 9.29
01/10/21 9.55 9.40
01/11/21 9.37 9.33
01/12/21 9.32 9.08
01/13/21 9.25 9.10
01/14/21 9.29 9.01
01/15/21 9.27 9.29
01/16/21 9.35 8.88
01/17/21 9.37 9.34
01/18/21 9.45 9.14
01/19/21 8.48 8.39
01/20/21 9.25 8.84
01/21/21 9.38 9.24
01/22/21 9.27 9.37
01/23/21 9.32 9.09
01/24/21 9.55 9.54
01/25/21 9.55 9.70
01/26/21 9.38 9.11
01/27/21 9.31 9.49
01/28/21 9.86 9.59
01/29/21 9.91 10.10
01/30/21 9.64 9.80
01/31/21 9.66 9.54
02/01/21 9.59 9.42
02/02/21 9.42 9.30
02/03/21 9.46 9.42
02/04/21 9.43 9.29
02/05/21 9.40 9.25
02/06/21 9.49 9.32
02/07/21 9.63 9.55
02/08/21 9.46 9.47
02/09/21 9.38 9.18
02/10/21 9.39 9.47
02/11/21 9.00 8.70
02/12/21 8.12 9.46
02/13/21 8.07 5.45
02/14/21 8.09 9.21
02/15/21 8.41 8.20
02/16/21 8.20 8.10
02/17/21 8.12 8.19
02/18/21 8.73 8.71
02/19/21 8.61 8.57
City of Thousand Oaks
Hill Canyon Treatment Plant D-14 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
02/20/21 8.29 8.17
02/21/21 8.44 8.23
02/22/21 8.37 8.15
02/23/21 8.29 7.92
02/24/21 8.31 8.07
02/25/21 8.33 8.41
02/26/21 8.26 7.94
02/27/21 8.30 8.13
02/28/21 8.44 8.21
03/01/21 8.42 8.27
03/02/21 8.83 8.65
03/03/21 9.44 9.43
03/04/21 9.37 9.45
03/05/21 9.39 9.24
03/06/21 9.43 9.41
03/07/21 9.51 9.31
03/08/21 9.43 9.31
03/09/21 9.31 9.17
03/10/21 9.67 9.69
03/11/21 9.39 9.48
03/12/21 9.33 9.50
03/13/21 9.36 9.13
03/14/21 9.47 9.61
03/15/21 9.51 9.22
03/16/21 9.57 9.42
03/17/21 9.47 9.36
03/18/21 9.37 9.23
03/19/21 9.44 9.36
03/20/21 9.38 9.20
03/21/21 9.49 9.35
03/22/21 9.56 9.60
03/23/21 9.53 9.27
03/24/21 9.51 9.37
03/25/21 9.40 9.29
03/26/21 9.35 9.31
03/27/21 9.48 9.23
03/28/21 9.58 9.27
03/29/21 9.47 9.46
03/30/21 9.17 9.13
03/31/21 8.41 8.24
04/01/21 8.40 8.21
04/02/21 8.54 8.27
04/03/21 8.40 8.15
04/04/21 8.33 8.20
04/05/21 8.30 7.96
City of Thousand Oaks
Hill Canyon Treatment Plant D-15 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
04/06/21 8.28 8.16
04/07/21 8.21 8.21
04/08/21 8.19 8.11
04/09/21 8.21 7.88
04/10/21 8.21 8.12
04/11/21 8.40 8.06
04/12/21 8.53 8.41
04/13/21 8.37 8.21
04/14/21 8.40 8.06
04/15/21 8.42 8.21
04/16/21 8.47 8.68
04/17/21 8.49 8.21
04/18/21 8.65 8.21
04/19/21 8.53 8.37
04/20/21 8.42 8.15
04/21/21 8.42 8.46
04/22/21 8.47 8.55
04/23/21 8.43 8.56
04/24/21 8.40 8.17
04/25/21 8.54 8.55
04/26/21 8.46 8.18
04/27/21 8.44 8.34
04/28/21 8.33 8.21
04/29/21 8.27 8.47
04/30/21 8.28 8.25
05/01/21 8.12 8.00
05/02/21 8.21 8.37
05/03/21 8.19 8.19
05/04/21 8.20 8.21
05/05/21 8.24 8.22
05/06/21 8.20 8.07
05/07/21 8.10 8.18
05/08/21 8.14 8.05
05/09/21 8.26 8.48
05/10/21 8.31 8.21
05/11/21 8.22 8.37
05/12/21 8.24 8.19
05/13/21 8.12 8.18
05/14/21 8.20 8.46
05/15/21 8.03 7.88
05/16/21 8.18 8.43
05/17/21 8.24 8.16
05/18/21 8.15 8.30
05/19/21 8.09 7.80
05/20/21 8.05 8.37
City of Thousand Oaks
Hill Canyon Treatment Plant D-16 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
05/21/21 8.10 8.10
05/22/21 8.02 8.63
05/23/21 8.13 7.71
05/24/21 8.15 8.14
05/25/21 8.23 8.06
05/26/21 8.09 8.10
05/27/21 8.03 7.99
05/28/21 8.11 8.19
05/29/21 7.88 7.79
05/30/21 7.85 8.13
05/31/21 8.24 8.25
06/01/21 8.25 8.34
06/02/21 8.20 8.09
06/03/21 8.15 8.30
06/04/21 8.16 8.10
06/05/21 8.16 8.08
06/06/21 8.27 8.50
06/07/21 8.14 8.09
06/08/21 8.28 8.33
06/09/21 8.19 8.17
06/10/21 8.09 8.17
06/11/21 8.30 8.11
06/12/21 8.23 8.32
06/13/21 8.25 8.21
06/14/21 8.31 8.39
06/15/21 8.17 8.06
06/16/21 8.20 8.21
06/17/21 8.25 8.12
06/18/21 8.24 8.39
06/19/21 8.20 8.01
06/20/21 8.23 8.36
06/21/21 8.18 8.05
06/22/21 8.22 8.27
06/23/21 8.23 8.14
06/24/21 8.10 8.24
06/25/21 8.25 8.10
06/26/21 8.14 8.16
06/27/21 8.23 8.28
06/28/21 8.37 8.25
06/29/21 8.35 8.39
06/30/21 8.38 8.33
07/01/21 8.39 8.30
07/02/21 8.35 8.46
07/03/21 8.25 8.05
07/04/21 8.04 8.23
City of Thousand Oaks
Hill Canyon Treatment Plant D-17 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
07/05/21 8.48 8.22
07/06/21 8.25 8.38
07/07/21 8.25 8.14
07/08/21 8.25 8.28
07/09/21 8.30 8.10
07/10/21 8.32 8.28
07/11/21 8.31 8.18
07/12/21 8.40 8.48
07/13/21 8.32 8.16
07/14/21 8.38 8.37
07/15/21 8.28 8.18
07/16/21 8.34 8.78
07/17/21 8.30 7.85
07/18/21 8.26 8.17
07/19/21 8.28 8.29
07/20/21 8.26 8.02
07/21/21 8.32 8.38
07/22/21 8.32 8.23
07/23/21 8.38 8.11
07/24/21 8.59 8.77
07/25/21 8.62 8.67
07/26/21 8.40 8.46
07/27/21 8.20 8.17
07/28/21 8.21 8.30
07/29/21 8.15 8.17
07/30/21 8.16 8.08
07/31/21 8.06 7.91
08/01/21 8.09 8.12
08/02/21 8.01 7.89
08/03/21 8.00 7.90
08/04/21 8.10 8.06
08/05/21 8.12 8.15
08/06/21 8.12 8.68
08/07/21 8.20 8.59
08/08/21 8.23 8.42
08/09/21 8.51 8.42
08/10/21 8.43 8.47
08/11/21 8.21 8.14
08/12/21 8.23 7.89
08/13/21 8.12 8.06
08/14/21 8.10 7.90
08/15/21 8.28 8.31
08/16/21 8.34 8.40
08/17/21 8.38 8.21
08/18/21 8.25 8.49
City of Thousand Oaks
Hill Canyon Treatment Plant D-18 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
08/19/21 8.16 8.11
08/20/21 8.18 8.42
08/21/21 8.07 7.87
08/22/21 8.39 8.42
08/23/21 8.19 8.15
08/24/21 8.10 7.54
08/25/21 8.15 7.22
08/26/21 8.22 8.38
08/27/21 8.20 8.68
08/28/21 8.18 9.00
08/29/21 8.36 8.46
08/30/21 8.27 8.30
08/31/21 8.16 8.22
09/01/21 8.16 8.14
09/02/21 8.15 8.30
09/03/21 8.13 8.08
09/04/21 7.95 7.87
09/05/21 7.83 7.79
09/06/21 8.24 8.27
09/07/21 8.37 8.19
09/08/21 8.20 8.30
09/09/21 8.12 8.25
09/10/21 8.07 7.97
09/11/21 8.08 7.84
09/12/21 8.26 8.44
09/13/21 8.08 8.04
09/14/21 8.00 7.92
09/15/21 8.00 7.96
09/16/21 8.11 8.13
09/17/21 8.06 7.95
09/18/21 7.90 7.88
09/19/21 8.15 8.07
09/20/21 8.17 8.23
09/21/21 8.17 8.13
09/22/21 8.00 8.00
09/23/21 7.98 8.16
09/24/21 7.87 7.71
09/25/21 7.91 7.99
09/26/21 8.13 8.09
09/27/21 8.07 8.29
09/28/21 7.89 7.84
09/29/21 8.09 8.10
09/30/21 8.03 7.93
10/01/21 8.02 7.80
10/02/21 7.93 7.85
City of Thousand Oaks
Hill Canyon Treatment Plant D-19 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
10/03/21 8.15 8.17
10/04/21 7.95 7.82
10/05/21 8.05 7.98
10/06/21 8.13 7.97
10/07/21 8.00 8.21
10/08/21 7.96 7.68
10/09/21 8.00 7.93
10/10/21 8.21 8.15
10/11/21 8.11 8.22
10/12/21 8.19 8.12
10/13/21 8.20 7.99
10/14/21 8.10 8.08
10/15/21 8.16 7.91
10/16/21 8.24 8.11
10/17/21 8.42 8.36
10/18/21 8.17 8.34
10/19/21 8.06 7.89
10/20/21 8.01 8.09
10/21/21 7.97 7.78
10/22/21 7.88 8.02
10/23/21 7.92 7.70
10/24/21 8.13 8.18
10/25/21 8.36 8.64
10/26/21 8.05 8.08
10/27/21 8.07 8.15
10/28/21 8.04 7.88
10/29/21 8.03 7.89
10/30/21 8.07 8.59
10/31/21 7.96 7.48
11/01/21 8.17 8.13
11/02/21 7.99 7.83
11/03/21 7.83 7.94
11/04/21 7.83 7.94
11/05/21 7.93 7.98
11/06/21 7.91 7.79
11/07/21 8.02 8.28
11/08/21 7.95 7.84
11/09/21 7.93 8.08
11/10/21 8.03 7.80
11/11/21 8.21 8.22
11/12/21 7.95 7.81
11/13/21 7.95 7.60
11/14/21 8.05 8.09
11/15/21 7.88 7.87
11/16/21 7.85 7.84
City of Thousand Oaks
Hill Canyon Treatment Plant D-20 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
11/17/21 7.91 7.85
11/18/21 7.86 8.18
11/19/21 7.88 7.60
11/20/21 7.95 7.59
11/21/21 8.00 8.31
11/22/21 8.08 8.08
11/23/21 8.08 8.03
11/24/21 8.12 8.02
11/25/21 7.97 7.97
11/26/21 7.85 7.85
11/27/21 7.81 7.69
11/28/21 8.11 7.91
11/29/21 7.96 8.15
11/30/21 7.86 7.83
12/01/21 7.91 8.03
12/02/21 7.94 7.91
12/03/21 7.78 7.67
12/04/21 7.80 7.72
12/05/21 8.08 8.14
12/06/21 7.93 7.48
12/07/21 7.79 6.80
12/08/21 7.88 7.96
12/09/21 7.78 7.78
12/10/21 7.93 9.22
12/11/21 7.87 5.28
12/12/21 8.04 9.32
12/13/21 7.93 7.88
12/14/21 10.82 11.21
12/15/21 8.63 8.78
12/16/21 8.36 8.62
12/17/21 8.41 8.58
12/18/21 8.37 8.19
12/19/21 8.27 8.59
12/20/21 8.26 8.03
12/21/21 8.17 8.33
12/22/21 8.22 8.32
12/23/21 11.48 10.76
12/24/21 11.40 12.06
12/25/21 9.25 10.23
12/26/21 9.62 10.14
12/27/21 9.31 9.40
12/28/21 9.15 9.43
12/29/21 9.46 9.38
12/30/21 18.09 15.69
12/31/21 12.50 15.39
City of Thousand Oaks
Hill Canyon Treatment Plant D-21 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
01/01/22 10.35 11.10
01/02/22 10.01 10.21
01/03/22 9.74 9.88
01/04/22 9.69 9.63
01/05/22 9.43 9.32
01/06/22 9.37 9.16
01/07/22 9.26 9.80
01/08/22 9.32 8.97
01/09/22 9.39 9.24
01/10/22 9.07 8.98
01/11/22 8.96 8.60
01/12/22 8.87 8.67
01/13/22 8.78 8.75
01/14/22 8.74 8.61
01/15/22 8.64 8.35
01/16/22 8.80 8.56
01/17/22 9.09 9.03
01/18/22 8.76 8.59
01/19/22 8.74 8.64
01/20/22 8.73 8.49
01/21/22 8.75 8.66
01/22/22 8.78 8.51
01/23/22 8.90 8.92
01/24/22 8.75 8.48
01/25/22 8.67 8.61
01/26/22 8.69 8.68
01/27/22 8.67 8.55
01/28/22 8.62 8.86
01/29/22 8.68 8.62
01/30/22 8.86 8.68
01/31/22 8.77 8.68
02/01/22 8.70 8.43
02/02/22 8.65 8.35
02/03/22 8.62 8.56
02/04/22 8.53 8.54
02/05/22 8.61 8.26
02/06/22 8.86 8.77
02/07/22 9.18 9.27
02/08/22 8.06 8.35
02/09/22 8.53 8.39
02/10/22 8.53 8.51
02/11/22 8.46 8.35
02/12/22 8.66 8.33
02/13/22 8.69 8.62
02/14/22 8.58 8.33
City of Thousand Oaks
Hill Canyon Treatment Plant D-22 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
02/15/22 8.48 8.48
02/16/22 8.55 8.28
02/17/22 8.43 8.41
02/18/22 8.41 8.14
02/19/22 8.25 8.74
02/20/22 8.22 8.35
02/21/22 8.71 8.53
02/22/22 8.45 8.28
02/23/22 8.37 8.34
02/24/22 8.32 8.04
02/25/22 8.30 8.20
02/26/22 8.34 8.21
02/27/22 8.61 8.53
02/28/22 8.49 8.21
03/01/22 8.38 8.03
03/02/22 8.30 8.15
03/03/22 8.33 8.09
03/04/22 8.29 8.04
03/05/22 8.36 8.16
03/06/22 8.46 8.60
03/07/22 8.38 8.16
03/08/22 8.21 8.03
03/09/22 8.26 8.17
03/10/22 8.28 8.09
03/11/22 8.19 7.97
03/12/22 8.26 8.00
03/13/22 8.53 8.53
03/14/22 8.44 8.18
03/15/22 8.26 8.04
03/16/22 8.30 8.06
03/17/22 8.32 8.11
03/18/22 8.32 8.21
03/19/22 8.24 8.22
03/20/22 8.56 8.38
03/21/22 8.41 8.29
03/22/22 8.29 8.21
03/23/22 8.36 8.15
03/24/22 8.35 8.00
03/25/22 8.21 8.06
03/26/22 8.32 8.21
03/27/22 8.43 8.47
03/28/22 9.31 9.36
03/29/22 8.85 8.72
03/30/22 8.41 8.31
03/31/22 8.37 8.62
City of Thousand Oaks
Hill Canyon Treatment Plant D-23 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
04/01/22 8.30 8.51
04/02/22 8.13 8.31
04/03/22 8.40 8.48
04/04/22 8.36 8.46
04/05/22 8.21 8.13
04/06/22 8.26 8.17
04/07/22 8.30 8.12
04/08/22 8.09 8.00
04/09/22 8.15 7.88
04/10/22 8.25 8.23
04/11/22 8.15 8.24
04/12/22 8.08 7.88
04/13/22 8.12 8.26
04/14/22 8.03 7.91
04/15/22 8.12 8.06
04/16/22 7.99 7.82
04/17/22 7.92 8.22
04/18/22 7.87 7.73
04/19/22 7.79 7.87
04/20/22 7.75 7.72
04/21/22 7.81 7.87
04/22/22 8.14 8.10
04/23/22 8.00 7.81
04/24/22 8.26 8.28
04/25/22 8.29 8.15
04/26/22 8.08 7.97
04/27/22 8.07 8.14
04/28/22 8.00 7.87
04/29/22 7.94 7.90
04/30/22 7.93 7.82
05/01/22 8.21 8.30
05/02/22 8.07 7.94
05/03/22 8.01 8.08
05/04/22 8.09 8.07
05/05/22 8.00 7.86
05/06/22 7.90 7.98
05/07/22 8.04 7.92
05/08/22 8.05 8.25
05/09/22 8.17 8.04
05/10/22 7.80 7.97
05/11/22 8.08 8.12
05/12/22 7.97 7.94
05/13/22 8.04 7.97
05/14/22 8.02 7.85
05/15/22 8.11 8.29
City of Thousand Oaks
Hill Canyon Treatment Plant D-24 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
05/16/22 8.10 8.20
05/17/22 7.93 8.34
05/18/22 7.98 8.06
05/19/22 8.00 7.80
05/20/22 7.84 7.94
05/21/22 7.92 7.74
05/22/22 8.12 8.34
05/23/22 8.04 8.05
05/24/22 7.98 7.83
05/25/22 8.09 8.21
05/26/22 7.91 7.86
05/27/22 7.91 7.78
05/28/22 7.77 7.70
05/29/22 7.66 7.86
05/30/22 8.17 7.90
05/31/22 8.00 8.02
06/01/22 7.90 8.02
06/02/22 7.84 7.69
06/03/22 7.83 7.75
06/04/22 7.86 7.73
06/05/22 8.06 8.24
06/06/22 8.03 7.85
06/07/22 7.95 7.92
06/08/22 7.93 7.95
06/09/22 7.99 8.05
06/10/22 8.03 7.74
06/11/22 7.89 7.90
06/12/22 7.94 8.14
06/13/22 7.85 7.68
06/14/22 7.90 7.90
06/15/22 7.91 7.83
06/16/22 7.89 8.17
06/17/22 7.69 8.40
06/18/22 7.68 5.22
06/19/22 7.68 8.88
06/20/22 7.87 7.65
06/21/22 7.78 7.57
06/22/22 7.39 7.79
06/23/22 7.82 7.81
06/24/22 7.76 7.56
06/25/22 7.66 7.60
06/26/22 7.68 7.46
06/27/22 7.83 7.70
06/28/22 7.76 7.50
06/29/22 7.88 7.83
City of Thousand Oaks
Hill Canyon Treatment Plant D-25 October 2023
Appendix D - Local Limits Data Summary
Date Influent
(MGD)
Effluent
(MGD)
06/30/22 7.84 7.70
City of Thousand Oaks
Hill Canyon Treatment Plant D-26 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Collection System Ammonia as N 06/01/22 71 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Collection System Ammonia as N 06/02/22 75 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Collection System Ammonia as N 06/03/22 72 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Collection System Ammonia as N 06/04/22 85 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Collection System Ammonia as N 06/05/22 85 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Collection System Ammonia as N 06/06/22 73 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Collection System Ammonia as N 06/07/22 64 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Collection System Arsenic 06/01/22 3.1 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Arsenic 06/02/22 2.5 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Arsenic 06/03/22 2.4 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Arsenic 06/04/22 2.6 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Arsenic 06/05/22 2.8 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Arsenic 06/06/22 J 2.7 3.2 0.59 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Arsenic 06/07/22 2.5 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Barium 06/01/22 62 2 0.28 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Biochemical Oxygen Demand 06/01/22 350 2 2 mg/L SM 5210 B Weck Laboratories, Inc.
Collection System Biochemical Oxygen Demand 06/02/22 450 2 2 mg/L SM 5210 B Weck Laboratories, Inc.
Collection System Biochemical Oxygen Demand 06/03/22 270 2 2 mg/L SM 5210 B Weck Laboratories, Inc.
Collection System Biochemical Oxygen Demand 06/04/22 400 2 2 mg/L SM 5210 B Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Biochemical Oxygen Demand 06/05/22 410 2 2 mg/L SM 5210 B Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Biochemical Oxygen Demand 06/06/22 370 2 2 mg/L SM 5210 B Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Biochemical Oxygen Demand 06/07/22 270 2 2 mg/L SM 5210 B Weck Laboratories, Inc.
Collection System Boron 06/01/22 350 20 6 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Boron 06/02/22 320 20 6 ug/L EPA 200.7 Weck Laboratories, Inc.
Collection System Boron 06/03/22 160 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Collection System Boron 06/04/22 350 20 6 ug/L EPA 200.7 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Boron 06/05/22 390 20 6 ug/L EPA 200.7 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Boron 06/06/22 440 20 6 ug/L EPA 200.7 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Boron 06/07/22 300 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Collection System Cadmium 06/01/22 J 0.39 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Cadmium 06/02/22 J 0.11 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Cadmium 06/03/22 J 0.13 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Cadmium 06/04/22 J 0.21 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Cadmium 06/05/22 J 0.2 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Cadmium 06/06/22 < 0.34 1.6 0.34 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Cadmium 06/07/22 J 0.14 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Chloride 06/01/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Chloride 06/02/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Chloride 06/03/22 190 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Chloride 06/04/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Chloride 06/05/22 160 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Chloride 06/06/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Chloride 06/07/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Chromium 06/01/22 < 2.7 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc. Equipment blank contamination at 5.2 ug/L. Qualified as non-detect.
Collection System Chromium 06/02/22 < 1.3 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc. Equipment blank contamination at 5.2 ug/L. Qualified as non-detect.
Collection System Chromium 06/03/22 < 1.6 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc. Equipment blank contamination at 5.2 ug/L. Qualified as non-detect.
Collection System Chromium 06/04/22 < 2.3 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc. Equipment blank contamination at 5.2 ug/L. Qualified as non-detect.
Collection System Chromium 06/05/22 < 2.6 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc. Equipment blank contamination at 5.2 ug/L. Qualified as non-detect.
Collection System Chromium 06/06/22 < 2.7 1.6 0.71 ug/L EPA 200.8 Weck Laboratories, Inc. Equipment blank contamination at 5.2 ug/L. Qualified as non-detect.
Collection System Chromium 06/07/22 < 1.5 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc. Equipment blank contamination at 5.2 ug/L. Qualified as non-detect.
Collection System Cobalt 06/01/22 0.51 0.2 0.031 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Copper 06/01/22 59 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Copper 06/02/22 32 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Copper 06/03/22 33 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Copper 06/04/22 65 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Copper 06/05/22 54 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Copper 06/06/22 59 4 1.8 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Copper 06/07/22 43 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Cyanide 06/01/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Collection System Cyanide 06/02/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
City of Thousand Oaks
Hill Canyon Treatment Plant D-27 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Collection System Cyanide 06/03/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Collection System Cyanide 06/04/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Collection System Cyanide 06/05/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Collection System Cyanide 06/06/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Collection System Cyanide 06/07/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Collection System Lead 06/01/22 1.6 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Lead 06/02/22 0.59 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Lead 06/03/22 0.99 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Lead 06/04/22 1.2 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Lead 06/05/22 1.5 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Lead 06/06/22 2.8 1.6 0.66 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Lead 06/07/22 0.91 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Mercury 06/01/22 0.098 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Collection System Mercury 06/02/22 0.05 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Collection System Mercury 06/03/22 0.054 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Collection System Mercury 06/04/22 < 0.037 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Mercury 06/05/22 < 0.037 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Mercury 06/06/22 J 0.048 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Mercury 06/07/22 J 0.039 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Collection System Molybdenum 06/01/22 5.3 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Molybdenum 06/02/22 4.9 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Molybdenum 06/03/22 5.3 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Molybdenum 06/04/22 5.2 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Molybdenum 06/05/22 6 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Molybdenum 06/06/22 6.4 0.8 0.16 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Molybdenum 06/07/22 5.6 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Nickel 06/01/22 4.3 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Nickel 06/02/22 J 2.6 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Nickel 06/03/22 J 3.1 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Nickel 06/04/22 J 3.6 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Nickel 06/05/22 4.9 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Nickel 06/06/22 J 3.3 16 1.3 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Nickel 06/07/22 2.8 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Selenium 06/01/22 1.5 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Selenium 06/02/22 1.3 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Selenium 06/03/22 1.3 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Selenium 06/04/22 1.4 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Selenium 06/05/22 1.5 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Selenium 06/06/22 J 2 3.2 0.54 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Selenium 06/07/22 1.4 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Silver 06/01/22 J 0.37 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Silver 06/02/22 < 0.26 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Silver 06/03/22 < 0.26 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Silver 06/04/22 < 0.26 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Silver 06/05/22 J 0.35 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Silver 06/06/22 < 1 1.6 1 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Silver 06/07/22 0.2 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Sulfate as SO4 06/01/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Sulfate as SO4 06/02/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Sulfate as SO4 06/03/22 120 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Sulfate as SO4 06/04/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Sulfate as SO4 06/05/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Sulfate as SO4 06/06/22 J 4.4 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Sulfate as SO4 06/07/22 140 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Collection System Sulfide as S 06/01/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Collection System Sulfide as S 06/02/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Collection System Sulfide as S 06/03/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Collection System Sulfide as S 06/04/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Collection System Sulfide as S 06/05/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
City of Thousand Oaks
Hill Canyon Treatment Plant D-28 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Collection System Sulfide as S 06/06/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Collection System Sulfide as S 06/07/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Collection System Total Dissolved Solids 06/01/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Collection System Total Dissolved Solids 06/02/22 660 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Collection System Total Dissolved Solids 06/03/22 660 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Collection System Total Dissolved Solids 06/04/22 640 10 4 mg/L SM 2540 C Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Total Dissolved Solids 06/05/22 650 10 4 mg/L SM 2540 C Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Total Dissolved Solids 06/06/22 680 10 4 mg/L SM 2540 C Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Total Dissolved Solids 06/07/22 620 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Collection System Total Suspended Solids 06/01/22 330 5 - mg/L SM 2540 D Weck Laboratories, Inc.
Collection System Total Suspended Solids 06/02/22 520 5 - mg/L SM 2540 D Weck Laboratories, Inc.
Collection System Total Suspended Solids 06/03/22 250 5 - mg/L SM 2540 D Weck Laboratories, Inc.
Collection System Total Suspended Solids 06/04/22 460 5 - mg/L SM 2540 D Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Total Suspended Solids 06/05/22 400 5 - mg/L SM 2540 D Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Total Suspended Solids 06/06/22 520 5 - mg/L SM 2540 D Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Total Suspended Solids 06/07/22 370 5 - mg/L SM 2540 D Weck Laboratories, Inc.
Collection System Vanadium 06/01/22 8.5 1 0.32 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Zinc 06/01/22 260 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Zinc 06/02/22 130 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Zinc 06/03/22 130 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Collection System Zinc 06/04/22 220 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Zinc 06/05/22 260 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Zinc 06/06/22 250 80 13 ug/L EPA 200.8 Weck Laboratories, Inc. Excluded from analysis due to composite sampling issues.
Collection System Zinc 06/07/22 160 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Ammonia as N 07/11/19 1.4 mg/L SM 4500-NH Final Effluent Ammonia as N 08/08/19 1.7 mg/L SM 4500-NH Final Effluent Ammonia as N 09/12/19 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 10/10/19 1.3 mg/L SM 4500-NH Final Effluent Ammonia as N 11/07/19 1.8 mg/L SM 4500-NH Final Effluent Ammonia as N 12/12/19 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 01/16/20 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 02/06/20 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 03/05/20 1.4 mg/L SM 4500-NH Final Effluent Ammonia as N 04/09/20 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 05/07/20 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 06/04/20 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 07/09/20 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 08/06/20 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 09/10/20 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 10/08/20 1.3 mg/L SM 4500-NH Final Effluent Ammonia as N 11/05/20 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 12/10/20 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 01/07/21 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 02/18/21 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 03/11/21 1.4 mg/L SM 4500-NH Final Effluent Ammonia as N 04/08/21 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 05/06/21 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 06/10/21 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 07/08/21 1.3 mg/L SM 4500-NH Final Effluent Ammonia as N 08/05/21 1.4 mg/L SM 4500-NH Final Effluent Ammonia as N 09/09/21 1.7 mg/L SM 4500-NH Final Effluent Ammonia as N 10/07/21 1.7 mg/L SM 4500-NH Final Effluent Ammonia as N 11/10/21 1.3 mg/L SM 4500-NH Final Effluent Ammonia as N 12/09/21 2 mg/L SM 4500-NH
Final Effluent Ammonia as N 01/06/22 1.8 mg/L SM 4500-NH Final Effluent Ammonia as N 02/10/22 1.6 mg/L SM 4500-NH Final Effluent Ammonia as N 03/10/22 1.7 mg/L SM 4500-NH Final Effluent Ammonia as N 04/07/22 1.9 mg/L SM 4500-NH Final Effluent Ammonia as N 05/05/22 1.5 mg/L SM 4500-NH Final Effluent Ammonia as N 06/01/22 1.4 0.1 0.017 mg/L EPA 350.1 Weck Laboratories, Inc.
City of Thousand Oaks
Hill Canyon Treatment Plant D-29 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Ammonia as N 06/02/22 1.3 0.1 0.017 mg/L EPA 350.1 Weck Laboratories, Inc.
Final Effluent Ammonia as N 06/03/22 1.3 0.1 0.017 mg/L EPA 350.1 Weck Laboratories, Inc.
Final Effluent Ammonia as N 06/04/22 1.3 0.1 0.017 mg/L EPA 350.1 Weck Laboratories, Inc.
Final Effluent Ammonia as N 06/05/22 1.4 0.1 0.017 mg/L EPA 350.1 Weck Laboratories, Inc.
Final Effluent Ammonia as N 06/06/22 1.3 0.1 0.017 mg/L EPA 350.1 Weck Laboratories, Inc.
Final Effluent Ammonia as N 06/07/22 1.3 0.1 0.017 mg/L EPA 350.1 Weck Laboratories, Inc.
Final Effluent Arsenic 08/08/19 2.2 ug/L EPA 200.8
Final Effluent Arsenic 02/06/20 2.1 ug/L EPA 200.8
Final Effluent Arsenic 08/06/20 2.2 ug/L EPA 200.8
Final Effluent Arsenic 02/18/21 4 ug/L EPA 200.8
Final Effluent Arsenic 08/05/21 2.9 ug/L EPA 200.8
Final Effluent Arsenic 02/10/22 3.6 ug/L EPA 200.8
Final Effluent Arsenic 06/01/22 3 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Arsenic 06/02/22 3.4 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Arsenic 06/03/22 3.7 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Arsenic 06/04/22 3.8 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Arsenic 06/05/22 4.2 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Arsenic 06/06/22 4 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Arsenic 06/07/22 3.6 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Biochemical Oxygen Demand 07/03/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/11/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/19/19 7.1 mg/L SM 5210 B Sample result was excluded from analysis because it is an outlier.
Final Effluent Biochemical Oxygen Demand 07/25/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/30/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/08/19 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/16/19 2.4 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/20/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/28/19 2.3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/06/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/12/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/18/19 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/24/19 2.1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/04/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/10/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/16/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/22/19 2.3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/30/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/07/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/15/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/19/19 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/27/19 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/05/19 < 1 1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/12/19 < 1 1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/19/19 < 1 1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/31/19 < 1 1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/08/20 2.2 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/16/20 < 1 1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/24/20 < 1 1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/28/20 < 1 1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/06/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/12/20 2.4 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/21/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/25/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/05/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/13/20 2.3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/19/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/25/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/31/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/09/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/17/20 < 2 2 mg/L SM 5210 B City of Thousand Oaks
Hill Canyon Treatment Plant D-30 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Biochemical Oxygen Demand 04/21/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/28/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/07/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/15/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/19/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/27/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/04/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/12/20 2.4 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/18/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/24/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/30/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/09/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/15/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/23/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/31/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/06/20 3.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/14/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/19/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/25/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/02/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/10/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/18/20 2.6 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/23/20 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/29/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/08/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/13/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/21/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/30/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/05/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/13/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/18/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/25/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/04/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/10/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/15/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/22/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/29/20 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/07/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/12/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/22/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/27/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/05/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/10/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/18/21 2.7 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/23/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/05/21 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/11/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/17/21 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/23/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/31/21 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/08/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/16/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/20/21 2.3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/28/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/06/21 2.1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/14/21 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/19/21 2.5 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/25/21 2.1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/04/21 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/10/21 < 2 2 mg/L SM 5210 B City of Thousand Oaks
Hill Canyon Treatment Plant D-31 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Biochemical Oxygen Demand 06/17/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/23/21 2.1 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/08/21 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/14/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/22/21 2.7 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 07/30/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/05/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/13/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/19/21 2.3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/25/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 08/31/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/09/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/14/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/24/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 09/29/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/07/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/12/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/21/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 10/28/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/05/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/10/21 2.6 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/18/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/24/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 11/30/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/09/21 2.6 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/17/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/23/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 12/29/21 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/06/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/14/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/19/22 2.6 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 01/25/22 2.7 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/02/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/10/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/15/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 02/25/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/04/22 2.5 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/06/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/10/22 2.3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/25/22 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 03/29/22 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/07/22 3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/15/22 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/21/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 04/27/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/05/22 2.2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/13/22 2.3 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/19/22 3.4 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 05/25/22 < 2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/02/22 1.9 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/09/22 2.2 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/17/22 1.9 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/22/22 1.9 2 mg/L SM 5210 B Final Effluent Biochemical Oxygen Demand 06/30/22 1.9 2 mg/L SM 5210 B Final Effluent Boron 07/11/19 400 ug/L SM 4500 B
Final Effluent Boron 08/08/19 400 ug/L SM 4500 B
Final Effluent Boron 09/12/19 400 ug/L SM 4500 B
Final Effluent Boron 10/10/19 400 ug/L SM 4500 B
Final Effluent Boron 11/07/19 400 ug/L SM 4500 B
Final Effluent Boron 12/12/19 400 ug/L SM 4500 B
City of Thousand Oaks
Hill Canyon Treatment Plant D-32 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Boron 01/16/20 400 ug/L SM 4500 B
Final Effluent Boron 02/06/20 400 ug/L SM 4500 B
Final Effluent Boron 03/05/20 400 ug/L SM 4500 B
Final Effluent Boron 04/09/20 300 ug/L SM 4500 B
Final Effluent Boron 05/07/20 300 ug/L SM 4500 B
Final Effluent Boron 06/04/20 400 ug/L SM 4500 B
Final Effluent Boron 07/09/20 400 ug/L SM 4500 B
Final Effluent Boron 08/06/20 400 ug/L SM 4500 B
Final Effluent Boron 09/10/20 400 ug/L SM 4500 B
Final Effluent Boron 10/08/20 400 ug/L SM 4500 B
Final Effluent Boron 11/05/20 400 ug/L SM 4500 B
Final Effluent Boron 12/10/20 300 ug/L SM 4500 B
Final Effluent Boron 01/07/21 400 ug/L SM 4500 B
Final Effluent Boron 02/18/21 400 ug/L SM 4500 B
Final Effluent Boron 03/11/21 500 ug/L SM 4500 B
Final Effluent Boron 04/08/21 500 ug/L SM 4500 B
Final Effluent Boron 05/06/21 500 ug/L SM 4500 B
Final Effluent Boron 06/10/21 500 ug/L SM 4500 B
Final Effluent Boron 07/08/21 300 ug/L SM 4500 B
Final Effluent Boron 08/05/21 500 ug/L SM 4500 B
Final Effluent Boron 09/09/21 500 ug/L SM 4500 B
Final Effluent Boron 10/07/21 400 ug/L SM 4500 B
Final Effluent Boron 11/10/21 400 ug/L SM 4500 B
Final Effluent Boron 12/09/21 400 ug/L SM 4500 B
Final Effluent Boron 01/06/22 500 ug/L SM 4500 B
Final Effluent Boron 02/10/22 400 ug/L SM 4500 B
Final Effluent Boron 03/10/22 500 ug/L SM 4500 B
Final Effluent Boron 04/07/22 400 ug/L SM 4500 B
Final Effluent Boron 05/05/22 500 ug/L SM 4500 B
Final Effluent Boron 06/01/22 400 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Final Effluent Boron 06/02/22 380 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Final Effluent Boron 06/03/22 380 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Final Effluent Boron 06/04/22 360 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Final Effluent Boron 06/05/22 370 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Final Effluent Boron 06/06/22 380 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Final Effluent Boron 06/07/22 380 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Final Effluent Cadmium 08/08/19 J 0.05 0.1 0.041 ug/L EPA 200.8 Final Effluent Cadmium 02/06/20 J 0.07 0.1 0.04 ug/L EPA 200.8 Final Effluent Cadmium 08/06/20 < 0.04 0.04 ug/L EPA 200.8 Final Effluent Cadmium 02/18/21 < 0.04 0.04 ug/L EPA 200.8 Final Effluent Cadmium 08/05/21 < 0.11 0.11 ug/L EPA 200.8 Final Effluent Cadmium 02/10/22 < 0.042 0.042 ug/L EPA 200.8 Final Effluent Cadmium 06/01/22 < 0.042 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Cadmium 06/02/22 < 0.042 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Cadmium 06/03/22 < 0.042 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Cadmium 06/04/22 < 0.042 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Cadmium 06/05/22 J 0.078 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Cadmium 06/06/22 < 0.042 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Cadmium 06/07/22 < 0.042 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Chloride 07/11/19 140 mg/L EPA 300.0
Final Effluent Chloride 08/08/19 140 mg/L EPA 300.0
Final Effluent Chloride 09/12/19 137 mg/L EPA 300.0
Final Effluent Chloride 10/10/19 134 mg/L EPA 300.0
Final Effluent Chloride 11/07/19 140 mg/L EPA 300.0
Final Effluent Chloride 12/12/19 130 mg/L EPA 300.0
Final Effluent Chloride 01/16/20 128 mg/L EPA 300.0
Final Effluent Chloride 02/06/20 141 mg/L EPA 300.0
Final Effluent Chloride 03/05/20 129 mg/L EPA 300.0
Final Effluent Chloride 04/09/20 123 mg/L EPA 300.0
Final Effluent Chloride 05/07/20 126 mg/L EPA 300.0
City of Thousand Oaks
Hill Canyon Treatment Plant D-33 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Chloride 06/04/20 125 mg/L EPA 300.0
Final Effluent Chloride 07/09/20 123 mg/L EPA 300.0
Final Effluent Chloride 08/06/20 124 mg/L EPA 300.0
Final Effluent Chloride 09/10/20 130 mg/L EPA 300.0
Final Effluent Chloride 10/08/20 130 mg/L EPA 300.0
Final Effluent Chloride 11/05/20 135 mg/L EPA 300.0
Final Effluent Chloride 12/10/20 133 mg/L EPA 300.0
Final Effluent Chloride 01/07/21 135 mg/L EPA 300.0
Final Effluent Chloride 02/18/21 136 mg/L EPA 300.0
Final Effluent Chloride 03/11/21 138 mg/L EPA 300.0
Final Effluent Chloride 04/08/21 135 mg/L EPA 300.0
Final Effluent Chloride 05/06/21 133 mg/L EPA 300.0
Final Effluent Chloride 06/10/21 135 mg/L EPA 300.0
Final Effluent Chloride 07/08/21 147 mg/L EPA 300.0
Final Effluent Chloride 08/05/21 147 mg/L EPA 300.0
Final Effluent Chloride 09/09/21 148 mg/L EPA 300.0
Final Effluent Chloride 10/07/21 160 mg/L EPA 300.0
Final Effluent Chloride 11/10/21 150 mg/L EPA 300.0
Final Effluent Chloride 12/09/21 133 mg/L EPA 300.0
Final Effluent Chloride 01/06/22 160 mg/L EPA 300.0
Final Effluent Chloride 02/10/22 152 mg/L EPA 300.0
Final Effluent Chloride 03/10/22 148 mg/L EPA 300.0
Final Effluent Chloride 04/07/22 153 mg/L EPA 300.0
Final Effluent Chloride 05/05/22 150 mg/L EPA 300.0
Final Effluent Chloride 06/01/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Chloride 06/02/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Chloride 06/03/22 160 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Chloride 06/04/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Chloride 06/05/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Chloride 06/06/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Chloride 06/07/22 150 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Chromium 08/08/19 0.29 ug/L EPA 200.8
Final Effluent Chromium 02/06/20 0.22 ug/L EPA 200.8
Final Effluent Chromium 08/06/20 0.29 ug/L EPA 200.8
Final Effluent Chromium 02/18/21 < 0.5 0.5 ug/L EPA 200.8 Final Effluent Chromium 08/05/21 1.8 ug/L EPA 200.8 Sample result was excluded from analysis because it is an outlier.
Final Effluent Chromium 02/10/22 0.33 ug/L EPA 200.8
Final Effluent Chromium 06/01/22 0.34 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Chromium 06/02/22 0.37 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Chromium 06/03/22 0.34 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Chromium 06/04/22 0.33 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Chromium 06/05/22 0.44 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Chromium 06/06/22 0.39 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Chromium 06/07/22 0.35 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Copper 07/11/19 2 ug/L EPA 200.8
Final Effluent Copper 08/08/19 5.2 ug/L EPA 200.8
Final Effluent Copper 09/12/19 3 ug/L EPA 200.8
Final Effluent Copper 10/10/19 2.3 ug/L EPA 200.8
Final Effluent Copper 11/07/19 2.6 ug/L EPA 200.8
Final Effluent Copper 12/12/19 8.3 ug/L EPA 200.8
Final Effluent Copper 01/16/20 3.7 ug/L EPA 200.8
Final Effluent Copper 02/06/20 2.8 ug/L EPA 200.8
Final Effluent Copper 03/05/20 5 ug/L EPA 200.8
Final Effluent Copper 04/09/20 16 ug/L EPA 200.8 Sample result was excluded from analysis because it is an outlier.
Final Effluent Copper 05/07/20 1.3 ug/L EPA 200.8
Final Effluent Copper 06/04/20 3.3 ug/L EPA 200.8
Final Effluent Copper 07/09/20 3.1 ug/L EPA 200.8
Final Effluent Copper 08/06/20 2.2 ug/L EPA 200.8
Final Effluent Copper 09/10/20 2 ug/L EPA 200.8
Final Effluent Copper 10/08/20 3.4 ug/L EPA 200.8
City of Thousand Oaks
Hill Canyon Treatment Plant D-34 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Copper 11/05/20 2.3 ug/L EPA 200.8
Final Effluent Copper 12/10/20 1.3 ug/L EPA 200.8
Final Effluent Copper 01/07/21 2.4 ug/L EPA 200.8
Final Effluent Copper 02/18/21 9 ug/L EPA 200.8
Final Effluent Copper 03/11/21 7.9 ug/L EPA 200.8
Final Effluent Copper 04/08/21 4.9 ug/L EPA 200.8
Final Effluent Copper 05/06/21 2.7 ug/L EPA 200.8
Final Effluent Copper 06/10/21 3.2 ug/L EPA 200.8
Final Effluent Copper 07/08/21 5.3 ug/L EPA 200.8
Final Effluent Copper 08/05/21 5.1 ug/L EPA 200.8
Final Effluent Copper 09/09/21 2.5 ug/L EPA 200.8
Final Effluent Copper 10/07/21 2.7 ug/L EPA 200.8
Final Effluent Copper 11/10/21 4.2 ug/L EPA 200.8
Final Effluent Copper 12/09/21 3.2 ug/L EPA 200.8
Final Effluent Copper 01/06/22 1.2 ug/L EPA 200.8
Final Effluent Copper 02/10/22 1.2 ug/L EPA 200.8
Final Effluent Copper 03/10/22 1.4 ug/L EPA 200.8
Final Effluent Copper 04/07/22 3.6 ug/L EPA 200.8
Final Effluent Copper 05/05/22 6.9 ug/L EPA 200.8
Final Effluent Copper 06/01/22 3.6 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Copper 06/02/22 2.6 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Copper 06/03/22 1.7 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Copper 06/04/22 2.4 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Copper 06/05/22 1.9 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Copper 06/06/22 1.5 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Copper 06/07/22 1.9 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Cyanide 07/11/19 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 08/08/19 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 09/12/19 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 10/10/19 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 11/07/19 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 12/12/19 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 01/16/20 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 02/05/20 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 03/04/20 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 04/08/20 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 05/06/20 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 06/03/20 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 07/08/20 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 08/05/20 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 09/09/20 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 10/07/20 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 11/04/20 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 12/09/20 4.4 ug/L EPA 335.4
Final Effluent Cyanide 01/06/21 J 3.1 4.2 1.7 ug/L EPA 335.4 Final Effluent Cyanide 02/17/21 J 1.7 4.2 1.7 ug/L EPA 335.4 Final Effluent Cyanide 03/10/21 J 3.6 4.2 2.7 ug/L EPA 335.4 Final Effluent Cyanide 04/07/21 J 3.9 4.2 1.7 ug/L EPA 335.4 Final Effluent Cyanide 05/05/21 < 1.7 1.7 ug/L EPA 335.4 Final Effluent Cyanide 06/09/21 < 1.7 1.7 ug/L EPA 335.4 Final Effluent Cyanide 07/07/21 < 2.7 2.7 ug/L EPA 335.4 Final Effluent Cyanide 08/04/21 6.4 ug/L EPA 335.4 Sample result was excluded from analysis because it is an outlier.
Final Effluent Cyanide 09/08/21 5.9 ug/L EPA 335.4
Final Effluent Cyanide 10/06/21 J 3.1 4.2 1.7 ug/L EPA 335.4 Final Effluent Cyanide 11/09/21 J 3.3 4.2 1.7 ug/L EPA 335.4 Final Effluent Cyanide 12/08/21 J 3.7 1.7 ug/L EPA 335.4 Final Effluent Cyanide 01/05/22 < 3.8 4.2 3.8 ug/L EPA 335.4 Final Effluent Cyanide 02/09/22 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 03/09/22 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 04/06/22 < 3.8 4.2 3.8 ug/L EPA 335.4 City of Thousand Oaks
Hill Canyon Treatment Plant D-35 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Cyanide 05/04/22 < 3.8 3.8 ug/L EPA 335.4 Final Effluent Cyanide 06/01/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Final Effluent Cyanide 06/02/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Final Effluent Cyanide 06/03/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Final Effluent Cyanide 06/04/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Final Effluent Cyanide 06/05/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Final Effluent Cyanide 06/06/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Final Effluent Cyanide 06/07/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Final Effluent Lead 08/08/19 J 0.06 ug/L EPA 200.8
Final Effluent Lead 02/06/20 J 0.087 ug/L EPA 200.8
Final Effluent Lead 08/06/20 J 0.081 ug/L EPA 200.8
Final Effluent Lead 02/18/21 J 0.12 ug/L EPA 200.8
Final Effluent Lead 08/05/21 < ND ug/L EPA 200.8 Sample result not used in analysis because it is non-detect and missing MDL/RL.
Final Effluent Lead 02/10/22 < ND ug/L EPA 200.8 Sample result not used in analysis because it is non-detect and missing MDL/RL.
Final Effluent Lead 06/01/22 < 0.083 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Lead 06/02/22 < 0.083 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Lead 06/03/22 < 0.083 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Lead 06/04/22 < 0.083 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Lead 06/05/22 J 0.091 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Lead 06/06/22 < 0.083 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Lead 06/07/22 < 0.083 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Mercury 07/11/19 < 0.025 0.025 ug/L EPA 245.1 Final Effluent Mercury 08/08/19 < 0.045 0.045 ug/L EPA 245.1 Final Effluent Mercury 09/12/19 < 0.025 0.025 ug/L EPA 245.1 Final Effluent Mercury 10/10/19 < 0.025 0.025 ug/L EPA 245.1 Final Effluent Mercury 11/07/19 < 0.025 0.025 ug/L EPA 245.1 Final Effluent Mercury 12/12/19 < 0.025 0.025 ug/L EPA 245.1 Final Effluent Mercury 06/01/22 0.00064 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Final Effluent Mercury 06/02/22 0.00063 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Final Effluent Mercury 06/03/22 0.0011 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Final Effluent Mercury 06/04/22 0.00067 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Final Effluent Mercury 06/05/22 0.0001 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Final Effluent Mercury 06/06/22 0.00059 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Final Effluent Mercury 06/07/22 0.00068 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Final Effluent Molybdenum 06/01/22 40 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Molybdenum 06/02/22 33 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Molybdenum 06/03/22 28 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Molybdenum 06/04/22 24 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Molybdenum 06/05/22 17 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Molybdenum 06/06/22 15 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Molybdenum 06/07/22 16 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Nickel 07/11/19 2.5 ug/L EPA 200.8
Final Effluent Nickel 08/08/19 2.9 ug/L EPA 200.8
Final Effluent Nickel 09/12/19 2.8 ug/L EPA 200.8
Final Effluent Nickel 10/10/19 2.4 ug/L EPA 200.8
Final Effluent Nickel 11/07/19 2.2 ug/L EPA 200.8
Final Effluent Nickel 12/12/19 2 ug/L EPA 200.8
Final Effluent Nickel 01/16/20 2.3 ug/L EPA 200.8
Final Effluent Nickel 02/06/20 1.7 ug/L EPA 200.8
Final Effluent Nickel 03/05/20 1.7 ug/L EPA 200.8
Final Effluent Nickel 04/09/20 2.1 ug/L EPA 200.8
Final Effluent Nickel 05/07/20 2 ug/L EPA 200.8
Final Effluent Nickel 06/04/20 2.3 ug/L EPA 200.8
Final Effluent Nickel 07/09/20 2.2 ug/L EPA 200.8
Final Effluent Nickel 08/06/20 1.9 ug/L EPA 200.8
Final Effluent Nickel 09/10/20 2 ug/L EPA 200.8
Final Effluent Nickel 10/08/20 1.8 ug/L EPA 200.8
Final Effluent Nickel 11/05/20 1.9 ug/L EPA 200.8
Final Effluent Nickel 12/10/20 3 ug/L EPA 200.8
Final Effluent Nickel 01/07/21 2.8 ug/L EPA 200.8
City of Thousand Oaks
Hill Canyon Treatment Plant D-36 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Nickel 02/18/21 2.4 ug/L EPA 200.8
Final Effluent Nickel 03/11/21 2.5 ug/L EPA 200.8
Final Effluent Nickel 04/08/21 3 ug/L EPA 200.8
Final Effluent Nickel 05/06/21 3.3 ug/L EPA 200.8
Final Effluent Nickel 06/10/21 3.6 ug/L EPA 200.8
Final Effluent Nickel 07/08/21 3.4 ug/L EPA 200.8
Final Effluent Nickel 08/05/21 3 ug/L EPA 200.8
Final Effluent Nickel 09/09/21 3.1 ug/L EPA 200.8
Final Effluent Nickel 10/07/21 2.8 ug/L EPA 200.8
Final Effluent Nickel 11/10/21 3.9 ug/L EPA 200.8
Final Effluent Nickel 12/09/21 3.8 ug/L EPA 200.8
Final Effluent Nickel 01/06/22 2.1 ug/L EPA 200.8
Final Effluent Nickel 02/10/22 J 1.9 0.2 0.16 ug/L EPA 200.8 Final Effluent Nickel 03/10/22 1.9 ug/L EPA 200.8
Final Effluent Nickel 04/07/22 2.2 ug/L EPA 200.8
Final Effluent Nickel 05/05/22 2 ug/L EPA 200.8
Final Effluent Nickel 06/01/22 2.2 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Nickel 06/02/22 2.1 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Nickel 06/03/22 2.2 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Nickel 06/04/22 2.2 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Nickel 06/05/22 2.5 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Nickel 06/06/22 2.2 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Nickel 06/07/22 2.2 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Selenium 08/08/19 0.24 ug/L EPA 200.8
Final Effluent Selenium 02/06/20 0.42 ug/L EPA 200.8
Final Effluent Selenium 08/06/20 J 0.29 0.4 0.14 ug/L EPA 200.8 Final Effluent Selenium 02/18/21 J 0.66 2 0.19 ug/L EPA 200.8 Final Effluent Selenium 08/05/21 J 1.2 2 0.19 ug/L EPA 200.8 Final Effluent Selenium 02/10/22 0.78 ug/L EPA 200.8
Final Effluent Selenium 06/01/22 0.51 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Selenium 06/02/22 0.49 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Selenium 06/03/22 0.47 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Selenium 06/04/22 0.41 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Selenium 06/05/22 0.48 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Selenium 06/06/22 0.42 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Selenium 06/07/22 0.51 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Silver 08/08/19 < 0.012 0.012 ug/L EPA 200.8 Final Effluent Silver 02/06/20 < 0.012 0.012 ug/L EPA 200.8 Final Effluent Silver 08/06/20 < 0.012 0.012 ug/L EPA 200.8 Final Effluent Silver 02/18/21 < 0.012 0.012 ug/L EPA 200.8 Final Effluent Silver 08/05/21 < 0.1 0.1 ug/L EPA 200.8 Final Effluent Silver 02/10/22 < 0.1 0.1 ug/L EPA 200.8 Final Effluent Silver 06/01/22 J 0.16 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Silver 06/02/22 < 0.13 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Silver 06/03/22 < 0.13 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Silver 06/04/22 < 0.13 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Silver 06/05/22 < 0.13 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Silver 06/06/22 < 0.13 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Silver 06/07/22 < 0.13 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Sulfate as SO4 07/11/19 107 mg/L EPA 300.0 Final Effluent Sulfate as SO4 08/08/19 110 mg/L EPA 300.0 Final Effluent Sulfate as SO4 09/12/19 107 mg/L EPA 300.0 Final Effluent Sulfate as SO4 10/10/19 107 mg/L EPA 300.0 Final Effluent Sulfate as SO4 11/07/19 120 mg/L EPA 300.0 Final Effluent Sulfate as SO4 12/12/19 101 mg/L EPA 300.0 Final Effluent Sulfate as SO4 01/16/20 102 mg/L EPA 300.0 Final Effluent Sulfate as SO4 02/06/20 106 mg/L EPA 300.0 Final Effluent Sulfate as SO4 03/05/20 98 mg/L EPA 300.0 City of Thousand Oaks
Hill Canyon Treatment Plant D-37 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Sulfate as SO4 04/09/20 103 mg/L EPA 300.0 Final Effluent Sulfate as SO4 05/07/20 105 mg/L EPA 300.0 Final Effluent Sulfate as SO4 06/04/20 102 mg/L EPA 300.0 Final Effluent Sulfate as SO4 07/09/20 99 mg/L EPA 300.0 Final Effluent Sulfate as SO4 08/06/20 139 mg/L EPA 300.0 Final Effluent Sulfate as SO4 09/10/20 156 mg/L EPA 300.0 Final Effluent Sulfate as SO4 10/08/20 150 mg/L EPA 300.0 Final Effluent Sulfate as SO4 11/05/20 141 mg/L EPA 300.0 Final Effluent Sulfate as SO4 12/10/20 149 mg/L EPA 300.0 Final Effluent Sulfate as SO4 01/07/21 151 mg/L EPA 300.0 Final Effluent Sulfate as SO4 02/18/21 103 mg/L EPA 300.0 Final Effluent Sulfate as SO4 03/11/21 151 mg/L EPA 300.0 Final Effluent Sulfate as SO4 04/08/21 114 mg/L EPA 300.0 Final Effluent Sulfate as SO4 05/06/21 97 mg/L EPA 300.0 Final Effluent Sulfate as SO4 06/10/21 98 mg/L EPA 300.0 Final Effluent Sulfate as SO4 07/08/21 127 mg/L EPA 300.0 Final Effluent Sulfate as SO4 08/05/21 131 mg/L EPA 300.0 Final Effluent Sulfate as SO4 09/09/21 140 mg/L EPA 300.0 Final Effluent Sulfate as SO4 10/07/21 140 mg/L EPA 300.0 Final Effluent Sulfate as SO4 11/10/21 160 mg/L EPA 300.0 Final Effluent Sulfate as SO4 12/09/21 149 mg/L EPA 300.0 Final Effluent Sulfate as SO4 01/06/22 150 mg/L EPA 300.0 Final Effluent Sulfate as SO4 02/10/22 175 mg/L EPA 300.0 Final Effluent Sulfate as SO4 03/10/22 127 mg/L EPA 300.0 Final Effluent Sulfate as SO4 04/07/22 175 mg/L EPA 300.0 Final Effluent Sulfate as SO4 05/05/22 153 mg/L EPA 300.0 Final Effluent Sulfate as SO4 06/01/22 140 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Sulfate as SO4 06/02/22 130 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Sulfate as SO4 06/03/22 130 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Sulfate as SO4 06/04/22 130 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Sulfate as SO4 06/05/22 130 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Sulfate as SO4 06/06/22 130 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Sulfate as SO4 06/07/22 140 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Final Effluent Total Dissolved Solids 07/11/19 585 mg/L SM 2540 C Final Effluent Total Dissolved Solids 08/08/19 594 mg/L SM 2540 C Final Effluent Total Dissolved Solids 09/12/19 578 mg/L SM 2540 C Final Effluent Total Dissolved Solids 10/10/19 578 mg/L SM 2540 C Final Effluent Total Dissolved Solids 11/07/19 561 mg/L SM 2540 C Final Effluent Total Dissolved Solids 12/12/19 556 mg/L SM 2540 C Final Effluent Total Dissolved Solids 01/16/20 551 mg/L SM 2540 C Final Effluent Total Dissolved Solids 02/06/20 575 mg/L SM 2540 C Final Effluent Total Dissolved Solids 03/05/20 562 mg/L SM 2540 C Final Effluent Total Dissolved Solids 04/09/20 555 mg/L SM 2540 C Final Effluent Total Dissolved Solids 05/07/20 543 mg/L SM 2540 C Final Effluent Total Dissolved Solids 06/04/20 546 mg/L SM 2540 C Final Effluent Total Dissolved Solids 07/09/20 546 mg/L SM 2540 C Final Effluent Total Dissolved Solids 08/06/20 631 mg/L SM 2540 C Final Effluent Total Dissolved Solids 09/10/20 649 mg/L SM 2540 C Final Effluent Total Dissolved Solids 10/08/20 638 mg/L SM 2540 C Final Effluent Total Dissolved Solids 11/05/20 633 mg/L SM 2540 C Final Effluent Total Dissolved Solids 12/10/20 661 mg/L SM 2540 C Final Effluent Total Dissolved Solids 01/07/21 648 mg/L SM 2540 C Final Effluent Total Dissolved Solids 02/18/21 565 mg/L SM 2540 C Final Effluent Total Dissolved Solids 03/11/21 645 mg/L SM 2540 C City of Thousand Oaks
Hill Canyon Treatment Plant D-38 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Total Dissolved Solids 04/08/21 563 mg/L SM 2540 C Final Effluent Total Dissolved Solids 05/06/21 550 mg/L SM 2540 C Final Effluent Total Dissolved Solids 06/10/21 576 mg/L SM 2540 C Final Effluent Total Dissolved Solids 07/08/21 591 mg/L SM 2540 C Final Effluent Total Dissolved Solids 08/05/21 626 mg/L SM 2540 C Final Effluent Total Dissolved Solids 09/09/21 652 mg/L SM 2540 C Final Effluent Total Dissolved Solids 10/07/21 674 mg/L SM 2540 C Final Effluent Total Dissolved Solids 11/10/21 674 mg/L SM 2540 C Final Effluent Total Dissolved Solids 12/09/21 661 mg/L SM 2540 C Final Effluent Total Dissolved Solids 01/06/22 676 mg/L SM 2540 C Final Effluent Total Dissolved Solids 02/10/22 681 mg/L SM 2540 C Final Effluent Total Dissolved Solids 03/10/22 616 mg/L SM 2540 C Final Effluent Total Dissolved Solids 04/07/22 700 mg/L SM 2540 C Final Effluent Total Dissolved Solids 05/05/22 670 mg/L SM 2540 C Final Effluent Total Dissolved Solids 06/01/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Final Effluent Total Dissolved Solids 06/02/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Final Effluent Total Dissolved Solids 06/03/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Final Effluent Total Dissolved Solids 06/04/22 610 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Final Effluent Total Dissolved Solids 06/05/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Final Effluent Total Dissolved Solids 06/06/22 590 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Final Effluent Total Dissolved Solids 06/07/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Final Effluent Total Suspended Solids 07/03/19 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/11/19 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/19/19 1.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/25/19 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/30/19 0.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/08/19 0.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/16/19 1.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/20/19 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/28/19 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/06/19 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/12/19 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/18/19 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/24/19 0.4 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/04/19 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/10/19 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/16/19 1.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/22/19 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/30/19 1.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/07/19 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/15/19 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/19/19 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/27/19 0.4 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/05/19 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/12/19 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/19/19 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/31/19 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/08/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/16/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/24/20 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/28/20 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/06/20 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/12/20 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/21/20 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/25/20 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/05/20 1.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/13/20 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/19/20 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/25/20 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/31/20 0.1 mg/L SM 2540 D City of Thousand Oaks
Hill Canyon Treatment Plant D-39 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Total Suspended Solids 04/09/20 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/17/20 1.4 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/21/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/28/20 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/07/20 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/15/20 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/19/20 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/27/20 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/04/20 0.4 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/12/20 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/18/20 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/24/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/30/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/09/20 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/15/20 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/23/20 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/31/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/06/20 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/14/20 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/19/20 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/25/20 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/02/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/10/20 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/18/20 1.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/23/20 0.4 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/29/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/08/20 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/13/20 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/21/20 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/30/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/05/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/13/20 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/18/20 0.4 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/25/20 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/04/20 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/10/20 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/15/20 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/22/20 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/29/20 0.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/07/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/22/21 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/27/21 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/05/21 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/10/21 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/18/21 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/23/21 1.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/05/21 1.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/11/21 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/17/21 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/23/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/31/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/08/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/16/21 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/20/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/28/21 0.4 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/06/21 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/14/21 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/19/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/25/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/04/21 0.7 mg/L SM 2540 D City of Thousand Oaks
Hill Canyon Treatment Plant D-40 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Total Suspended Solids 06/10/21 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/17/21 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/23/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/29/21 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/08/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/14/21 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/22/21 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 07/30/21 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/05/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/13/21 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/19/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/25/21 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 08/31/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/09/21 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/14/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/24/21 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 09/29/21 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/07/21 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/12/21 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/21/21 0.7 mg/L SM 2540 D Final Effluent Total Suspended Solids 10/28/21 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/05/21 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/10/21 1.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/18/21 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/24/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 11/30/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/09/21 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/17/21 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/23/21 1.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 12/29/21 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/06/22 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/14/22 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/19/22 1.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 01/25/22 1.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/02/22 1.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/10/22 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/15/22 1.3 mg/L SM 2540 D Final Effluent Total Suspended Solids 02/25/22 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/04/22 1.2 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/06/22 0.9 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/10/22 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/25/22 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 03/29/22 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/07/22 1 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/15/22 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/21/22 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 04/27/22 0.8 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/05/22 1.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/13/22 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/19/22 0.5 mg/L SM 2540 D Final Effluent Total Suspended Solids 05/25/22 0.6 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/02/22 0.5 0.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/09/22 0.8 0.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/17/22 0.8 0.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/22/22 0.5 0.1 mg/L SM 2540 D Final Effluent Total Suspended Solids 06/30/22 0.8 0.1 mg/L SM 2540 D Final Effluent Zinc 08/08/19 41 ug/L EPA 200.8
Final Effluent Zinc 02/06/20 35 ug/L EPA 200.8
Final Effluent Zinc 05/07/20 33 ug/L EPA 200.8
Final Effluent Zinc 08/06/20 43 ug/L EPA 200.8
City of Thousand Oaks
Hill Canyon Treatment Plant D-41 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Final Effluent Zinc 11/05/20 33 ug/L EPA 200.8
Final Effluent Zinc 02/18/21 45 ug/L EPA 200.8
Final Effluent Zinc 05/06/21 39 ug/L EPA 200.8
Final Effluent Zinc 08/05/21 46 ug/L EPA 200.8
Final Effluent Zinc 11/10/21 35 ug/L EPA 200.8
Final Effluent Zinc 02/10/22 33 ug/L EPA 200.8
Final Effluent Zinc 05/05/22 28 ug/L EPA 200.8
Final Effluent Zinc 06/01/22 27 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Zinc 06/02/22 28 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Zinc 06/03/22 34 10 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Zinc 06/04/22 28 10 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Zinc 06/05/22 32 10 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Zinc 06/06/22 31 10 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Final Effluent Zinc 06/07/22 31 10 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Ammonia as N 11/07/19 28.2 mg/L SM 4500-NH Excluded from analysis since collected as composite samples.
Influent Ammonia as N 02/06/20 32.6 mg/L SM 4500-NH Excluded from analysis since collected as composite samples.
Influent Ammonia as N 08/06/20 31.4 mg/L SM 4500-NH Excluded from analysis since collected as composite samples.
Influent Ammonia as N 02/18/21 30.8 0.07 mg/L SM 4500-NH Excluded from analysis since collected as composite samples.
Influent Ammonia as N 08/05/21 29.9 mg/L SM 4500-NH Excluded from analysis since collected as composite samples.
Influent Ammonia as N 02/10/22 35.2 mg/L SM 4500-NH Excluded from analysis since collected as composite samples.
Influent Ammonia as N 06/01/22 63 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Influent Ammonia as N 06/02/22 61 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Influent Ammonia as N 06/03/22 67 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Influent Ammonia as N 06/04/22 63 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Influent Ammonia as N 06/05/22 64 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Influent Ammonia as N 06/06/22 66 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Influent Ammonia as N 06/07/22 58 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Influent Arsenic 08/08/19 3.2 ug/L EPA 200.8
Influent Arsenic 02/06/20 3.9 ug/L EPA 200.8
Influent Arsenic 08/06/20 3.8 ug/L EPA 200.8
Influent Arsenic 02/18/21 4.3 ug/L EPA 200.8
Influent Arsenic 08/05/21 3.9 ug/L EPA 200.8
Influent Arsenic 02/10/22 4.9 ug/L EPA 200.8
Influent Arsenic 06/01/22 5.6 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Arsenic 06/02/22 6.6 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Arsenic 06/03/22 6.1 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Arsenic 06/04/22 5.1 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Arsenic 06/05/22 4.9 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Arsenic 06/06/22 5.5 3.2 0.59 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Arsenic 06/07/22 4.8 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Barium 02/06/20 50 ug/L EPA 200.8
Influent Barium 08/06/20 43 ug/L EPA 200.8
Influent Barium 02/18/21 50 ug/L EPA 200.8
Influent Barium 08/05/21 54 ug/L EPA 200.8
Influent Barium 02/10/22 69 ug/L EPA 200.8
Influent Barium 06/01/22 50 2 0.28 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Barium 06/02/22 55 2 0.28 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Barium 06/03/22 51 2 0.28 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Barium 06/04/22 44 1 0.14 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Barium 06/05/22 49 1 0.14 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Barium 06/06/22 53 8 1.1 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Barium 06/07/22 55 1 0.14 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Biochemical Oxygen Demand 07/03/19 331 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/11/19 296 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/19/19 285 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/25/19 304 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/30/19 243 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/08/19 283 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/16/19 197 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/20/19 286 mg/L SM 5210 B City of Thousand Oaks
Hill Canyon Treatment Plant D-42 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Biochemical Oxygen Demand 08/28/19 274 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/06/19 231 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/12/19 248 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/18/19 253 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/24/19 276 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/04/19 259 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/10/19 258 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/16/19 296 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/22/19 285 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/30/19 250 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/07/19 250 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/15/19 285 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/19/19 313 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/27/19 276 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/05/19 174 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/12/19 298 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/19/19 321 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/31/19 280 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/08/20 341 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/16/20 348 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/24/20 286 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/28/20 279 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/06/20 247 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/12/20 312 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/21/20 313 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/25/20 314 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/05/20 340 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/13/20 290 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/19/20 476 mg/L SM 5210 B Sample result was excluded from analysis because it is an outlier.
Influent Biochemical Oxygen Demand 03/25/20 255 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/31/20 281 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/09/20 331 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/17/20 378 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/21/20 283 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/28/20 331 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/07/20 286 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/15/20 264 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/19/20 270 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/27/20 245 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/04/20 273 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/12/20 376 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/18/20 321 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/24/20 338 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/30/20 259 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/09/20 264 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/15/20 300 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/23/20 292 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/31/20 320 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/06/20 249 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/14/20 290 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/19/20 242 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/25/20 242 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/02/20 277 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/10/20 250 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/18/20 293 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/23/20 246 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/29/20 283 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/08/20 279 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/13/20 266 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/21/20 264 mg/L SM 5210 B City of Thousand Oaks
Hill Canyon Treatment Plant D-43 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Biochemical Oxygen Demand 10/30/20 252 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/05/20 247 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/13/20 243 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/18/20 236 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/25/20 239 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/04/20 240 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/10/20 261 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/15/20 254 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/22/20 226 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/29/20 222 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/07/21 259 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/12/21 206 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/22/21 244 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/27/21 248 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/05/21 237 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/10/21 340 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/18/21 241 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/23/21 164 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/05/21 231 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/11/21 229 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/17/21 221 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/23/21 301 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/31/21 329 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/08/21 321 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/16/21 300 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/20/21 329 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/28/21 324 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/06/21 275 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/14/21 352 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/19/21 294 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/25/21 279 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/04/21 281 mg/L SM 5210 B 6-29-21 BOD invalidated this month - Lab error Influent Biochemical Oxygen Demand 06/10/21 307 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/17/21 283 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/23/21 290 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/08/21 211 mg/L SM 5210 B Inf sampler reset for 7-8/9-21, malfunction Influent Biochemical Oxygen Demand 07/14/21 279 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/22/21 278 mg/L SM 5210 B Influent Biochemical Oxygen Demand 07/30/21 284 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/05/21 244 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/13/21 317 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/19/21 284 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/25/21 296 mg/L SM 5210 B Influent Biochemical Oxygen Demand 08/31/21 181 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/09/21 265 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/14/21 282 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/24/21 247 mg/L SM 5210 B Influent Biochemical Oxygen Demand 09/29/21 272 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/07/21 282 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/12/21 258 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/21/21 257 mg/L SM 5210 B Influent Biochemical Oxygen Demand 10/28/21 270 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/05/21 266 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/10/21 284 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/18/21 290 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/24/21 292 mg/L SM 5210 B Influent Biochemical Oxygen Demand 11/30/21 335 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/09/21 313 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/17/21 192 mg/L SM 5210 B Influent Biochemical Oxygen Demand 12/23/21 326 mg/L SM 5210 B City of Thousand Oaks
Hill Canyon Treatment Plant D-44 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Biochemical Oxygen Demand 12/29/21 279 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/06/22 296 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/14/22 254 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/19/22 301 mg/L SM 5210 B Influent Biochemical Oxygen Demand 01/25/22 283 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/02/22 353 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/10/22 262 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/15/22 277 mg/L SM 5210 B Influent Biochemical Oxygen Demand 02/25/22 316 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/04/22 365 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/06/22 323 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/10/22 342 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/25/22 376 mg/L SM 5210 B Influent Biochemical Oxygen Demand 03/29/22 352 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/07/22 333 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/15/22 347 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/21/22 387 mg/L SM 5210 B Influent Biochemical Oxygen Demand 04/27/22 304 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/05/22 320 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/13/22 450 mg/L SM 5210 B Sample result was excluded from analysis because it is an outlier.
Influent Biochemical Oxygen Demand 05/19/22 370 mg/L SM 5210 B Influent Biochemical Oxygen Demand 05/25/22 379 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/02/22 318 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/09/22 349 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/17/22 321 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/22/22 321 mg/L SM 5210 B Influent Biochemical Oxygen Demand 06/30/22 329 mg/L SM 5210 B Influent Bis(2-ethylhexyl)phthalate 06/01/22 51 40 23 ug/L EPA 625.1 Weck Laboratories, Inc.
Influent Bis(2-ethylhexyl)phthalate 06/02/22 < 46 80 46 ug/L EPA 625.1 Weck Laboratories, Inc.
Influent Boron 02/06/20 500 ug/L SM 4500 B
Influent Boron 08/06/20 400 ug/L SM 4500 B
Influent Boron 02/18/21 400 3 ug/L SM 4500 B
Influent Boron 08/05/21 500 ug/L SM 4500 B
Influent Boron 02/10/22 400 ug/L SM 4500 B
Influent Boron 06/01/22 370 20 6 ug/L EPA 200.7 Weck Laboratories, Inc.
Influent Boron 06/02/22 350 20 6 ug/L EPA 200.7 Weck Laboratories, Inc.
Influent Boron 06/03/22 350 20 6 ug/L EPA 200.7 Weck Laboratories, Inc.
Influent Boron 06/04/22 350 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Influent Boron 06/05/22 360 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Influent Boron 06/06/22 380 20 6 ug/L EPA 200.7 Weck Laboratories, Inc.
Influent Boron 06/07/22 370 10 3 ug/L EPA 200.7 Weck Laboratories, Inc.
Influent Cadmium 08/08/19 0.26 ug/L EPA 200.8
Influent Cadmium 02/06/20 0.5 ug/L EPA 200.8
Influent Cadmium 08/06/20 0.1 ug/L EPA 200.8
Influent Cadmium 02/18/21 < 0.22 0.22 ug/L EPA 200.8
Influent Cadmium 08/05/21 < 0.11 0.11 ug/L EPA 200.8
Influent Cadmium 02/10/22 0.1 0.4 0.08 ug/L EPA 200.8
Influent Cadmium 06/01/22 J 0.14 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cadmium 06/02/22 J 0.17 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cadmium 06/03/22 J 0.15 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cadmium 06/04/22 J 0.13 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cadmium 06/05/22 J 0.13 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cadmium 06/06/22 < 0.34 1.6 0.34 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cadmium 06/07/22 J 0.16 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Chloride 08/08/19 126 mg/L EPA 300.0
Influent Chloride 11/07/19 120 mg/L EPA 300.0
Influent Chloride 02/06/20 130 mg/L EPA 300.0
Influent Chloride 08/06/20 125 mg/L EPA 300.0
Influent Chloride 02/18/21 118 0.14 mg/L EPA 300.0
Influent Chloride 08/05/21 127 mg/L EPA 300.0
City of Thousand Oaks
Hill Canyon Treatment Plant D-45 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Chloride 02/10/22 137 mg/L EPA 300.0
Influent Chloride 06/01/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Chloride 06/02/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Chloride 06/03/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Chloride 06/04/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Chloride 06/05/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Chloride 06/06/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Chloride 06/07/22 130 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Chromium 08/08/19 3.2 ug/L EPA 200.8
Influent Chromium 02/06/20 1.3 ug/L EPA 200.8
Influent Chromium 08/06/20 1.1 ug/L EPA 200.8
Influent Chromium 02/18/21 J 1.6 6 1 ug/L EPA 200.8
Influent Chromium 08/05/21 J 1.1 3 0.5 ug/L EPA 200.8
Influent Chromium 02/10/22 1.8 ug/L EPA 200.8
Influent Chromium 06/01/22 1.6 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Chromium 06/02/22 2.2 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Chromium 06/03/22 1.8 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Chromium 06/04/22 1.8 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Chromium 06/05/22 1.8 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Chromium 06/06/22 1.9 1.6 0.71 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Chromium 06/07/22 1.7 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cobalt 06/01/22 0.3 0.2 0.031 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cobalt 06/02/22 0.41 0.2 0.031 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cobalt 06/03/22 0.34 0.2 0.031 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cobalt 06/04/22 0.31 0.1 0.015 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cobalt 06/05/22 0.31 0.1 0.015 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cobalt 06/06/22 J 0.3 0.8 0.12 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cobalt 06/07/22 0.34 0.1 0.015 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Copper 08/08/19 54 ug/L EPA 200.8
Influent Copper 11/07/19 40 ug/L EPA 200.8
Influent Copper 02/06/20 44 ug/L EPA 200.8
Influent Copper 08/06/20 39 ug/L EPA 200.8
Influent Copper 02/18/21 46 ug/L EPA 200.8
Influent Copper 08/05/21 27 ug/L EPA 200.8
Influent Copper 02/10/22 42 ug/L EPA 200.8
Influent Copper 06/01/22 37 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Copper 06/02/22 47 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Copper 06/03/22 43 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Copper 06/04/22 39 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Copper 06/05/22 44 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Copper 06/06/22 41 4 1.8 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Copper 06/07/22 44 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Cyanide 08/08/19 < 2.7 2.7 ug/L EPA 335.4
Influent Cyanide 11/07/19 < 2.7 2.7 ug/L EPA 335.4
Influent Cyanide 02/05/20 < 2.7 2.7 ug/L EPA 335.4
Influent Cyanide 08/06/20 < 2.7 2.7 ug/L EPA 335.4
Influent Cyanide 02/18/21 < 1.7 1.7 ug/L EPA 335.4
Influent Cyanide 08/05/21 J 1.9 4.2 1.7 ug/L EPA 335.4
Influent Cyanide 02/10/22 < 1.7 1.7 ug/L EPA 335.4
Influent Cyanide 06/01/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Influent Cyanide 06/02/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Influent Cyanide 06/03/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Influent Cyanide 06/04/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Influent Cyanide 06/05/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Influent Cyanide 06/06/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Influent Cyanide 06/07/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Influent Lead 08/08/19 1.7 ug/L EPA 200.8
Influent Lead 02/06/20 0.9 ug/L EPA 200.8
Influent Lead 08/06/20 1.1 ug/L EPA 200.8
Influent Lead 02/18/21 2.3 ug/L EPA 200.8
City of Thousand Oaks
Hill Canyon Treatment Plant D-46 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Lead 08/05/21 J 0.9 ug/L EPA 200.8
Influent Lead 02/10/22 0.86 ug/L EPA 200.8
Influent Lead 06/01/22 0.79 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Lead 06/02/22 0.94 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Lead 06/03/22 0.87 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Lead 06/04/22 0.74 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Lead 06/05/22 0.75 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Lead 06/06/22 J 1.3 1.6 0.66 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Lead 06/07/22 0.83 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Mercury 08/08/19 J 0.04 0.05 0.025 ug/L EPA 245.1 Influent Mercury 11/07/19 0.08 ug/L EPA 245.1
Influent Mercury 02/18/21 0.014 0.001 ug/L EPA 245.1
Influent Mercury 06/01/22 0.091 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Influent Mercury 06/02/22 0.055 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Influent Mercury 06/03/22 0.18 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Influent Mercury 06/04/22 J 0.039 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Influent Mercury 06/05/22 < 0.037 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Influent Mercury 06/06/22 < 0.037 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Influent Mercury 06/07/22 J 0.049 0.05 0.037 ug/L EPA 245.1 Weck Laboratories, Inc.
Influent Molybdenum 06/01/22 28 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Molybdenum 06/02/22 22 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Molybdenum 06/03/22 20 0.2 0.04 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Molybdenum 06/04/22 13 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Molybdenum 06/05/22 13 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Molybdenum 06/06/22 21 0.8 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Molybdenum 06/07/22 33 0.1 0.02 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Nickel 08/08/19 4.9 ug/L EPA 200.8
Influent Nickel 11/07/19 2.7 ug/L EPA 200.8
Influent Nickel 02/06/20 2.7 ug/L EPA 200.8
Influent Nickel 08/06/20 3 ug/L EPA 200.8
Influent Nickel 02/18/21 4 ug/L EPA 200.8
Influent Nickel 08/05/21 3.8 ug/L EPA 200.8
Influent Nickel 02/10/22 J 3.4 4 0.33 ug/L EPA 200.8
Influent Nickel 06/01/22 J 3 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Nickel 06/02/22 J 3.2 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Nickel 06/03/22 J 3.3 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Nickel 06/04/22 2.6 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Nickel 06/05/22 3 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Nickel 06/06/22 J 2.1 16 1.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Nickel 06/07/22 3.1 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Selenium 08/08/19 J 0.66 0.8 0.28 ug/L EPA 200.8 Influent Selenium 02/06/20 1 ug/L EPA 200.8
Influent Selenium 08/06/20 0.7 ug/L EPA 200.8
Influent Selenium 02/18/21 J 1.8 4 0.38 ug/L EPA 200.8
Influent Selenium 08/05/21 J 1.6 2 0.19 ug/L EPA 200.8
Influent Selenium 02/10/22 1.5 ug/L EPA 200.8
Influent Selenium 06/01/22 1 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Selenium 06/02/22 1.2 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Selenium 06/03/22 1 0.8 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Selenium 06/04/22 0.92 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Selenium 06/05/22 0.98 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Selenium 06/06/22 J 1.2 3.2 0.54 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Selenium 06/07/22 1.1 0.4 0.067 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Silver 08/08/19 J 0.14 0.4 0.12 ug/L EPA 200.8 Influent Silver 02/06/20 0.2 ug/L EPA 200.8
Influent Silver 08/06/20 1.8 ug/L EPA 200.8 Sample result was excluded from analysis because it is an outlier.
Influent Silver 02/18/21 J 0.2 2 0.2 ug/L EPA 200.8
Influent Silver 08/05/21 J 0.2 1 0.1 ug/L EPA 200.8
Influent Silver 02/10/22 < 0.2 0.2 ug/L EPA 200.8
Influent Silver 06/01/22 J 0.36 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc.
City of Thousand Oaks
Hill Canyon Treatment Plant D-47 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Silver 06/02/22 0.35 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Silver 06/03/22 < 0.26 0.4 0.26 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Silver 06/04/22 0.25 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Silver 06/05/22 0.26 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Silver 06/06/22 < 1 1.6 1 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Silver 06/07/22 0.22 0.2 0.13 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Sulfate as SO4 08/08/19 96 mg/L EPA 300.0
Influent Sulfate as SO4 11/07/19 86 mg/L EPA 300.0
Influent Sulfate as SO4 02/06/20 92 mg/L EPA 300.0
Influent Sulfate as SO4 08/06/20 154 mg/L EPA 300.0
Influent Sulfate as SO4 02/18/21 84 mg/L EPA 300.0
Influent Sulfate as SO4 08/05/21 103 mg/L EPA 300.0
Influent Sulfate as SO4 02/10/22 147 mg/L EPA 300.0
Influent Sulfate as SO4 06/01/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Sulfate as SO4 06/02/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Sulfate as SO4 06/03/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Sulfate as SO4 06/04/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Sulfate as SO4 06/05/22 110 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Sulfate as SO4 06/06/22 120 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Sulfate as SO4 06/07/22 130 5 2.4 mg/L EPA 300.0 Weck Laboratories, Inc.
Influent Sulfide as S 06/01/22 0.3 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Influent Sulfide as S 06/02/22 0.3 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Influent Sulfide as S 06/03/22 0.3 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Influent Sulfide as S 06/04/22 0.1 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Influent Sulfide as S 06/05/22 0.7 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Influent Sulfide as S 06/06/22 0.4 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Influent Sulfide as S 06/07/22 0.4 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Influent Total Dissolved Solids 08/08/19 594 mg/L SM 2540 C Influent Total Dissolved Solids 11/07/19 549 mg/L SM 2540 C Influent Total Dissolved Solids 02/06/20 604 mg/L SM 2540 C Influent Total Dissolved Solids 08/06/20 690 mg/L SM 2540 C Influent Total Dissolved Solids 02/18/21 570 mg/L SM 2540 C Influent Total Dissolved Solids 08/05/21 624 mg/L SM 2540 C Influent Total Dissolved Solids 02/10/22 678 mg/L SM 2540 C Influent Total Dissolved Solids 06/01/22 590 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Influent Total Dissolved Solids 06/02/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Influent Total Dissolved Solids 06/03/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Influent Total Dissolved Solids 06/04/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Influent Total Dissolved Solids 06/05/22 590 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Influent Total Dissolved Solids 06/06/22 600 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Influent Total Dissolved Solids 06/07/22 630 10 4 mg/L SM 2540 C Weck Laboratories, Inc.
Influent Total Suspended Solids 07/03/19 392 mg/L SM 2540 D Influent Total Suspended Solids 07/11/19 378 mg/L SM 2540 D Influent Total Suspended Solids 07/19/19 387 mg/L SM 2540 D Influent Total Suspended Solids 07/25/19 314 mg/L SM 2540 D Influent Total Suspended Solids 07/30/19 268 mg/L SM 2540 D Influent Total Suspended Solids 08/08/19 295 mg/L SM 2540 D Influent Total Suspended Solids 08/16/19 235 mg/L SM 2540 D Influent Total Suspended Solids 08/20/19 325 mg/L SM 2540 D Influent Total Suspended Solids 08/28/19 299 mg/L SM 2540 D Influent Total Suspended Solids 09/06/19 258 mg/L SM 2540 D Influent Total Suspended Solids 09/12/19 324 mg/L SM 2540 D Influent Total Suspended Solids 09/18/19 287 mg/L SM 2540 D Influent Total Suspended Solids 09/24/19 156 mg/L SM 2540 D Influent Total Suspended Solids 10/04/19 287 mg/L SM 2540 D Influent Total Suspended Solids 10/10/19 286 mg/L SM 2540 D Influent Total Suspended Solids 10/16/19 296 mg/L SM 2540 D City of Thousand Oaks
Hill Canyon Treatment Plant D-48 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Total Suspended Solids 10/22/19 281 mg/L SM 2540 D Influent Total Suspended Solids 10/30/19 247 mg/L SM 2540 D Influent Total Suspended Solids 11/07/19 248 mg/L SM 2540 D Influent Total Suspended Solids 11/15/19 255 mg/L SM 2540 D Influent Total Suspended Solids 11/19/19 298 mg/L SM 2540 D Influent Total Suspended Solids 11/27/19 370 mg/L SM 2540 D Influent Total Suspended Solids 12/05/19 281 mg/L SM 2540 D Influent Total Suspended Solids 12/12/19 296 mg/L SM 2540 D Influent Total Suspended Solids 12/19/19 328 mg/L SM 2540 D Influent Total Suspended Solids 12/31/19 377 mg/L SM 2540 D Influent Total Suspended Solids 01/08/20 399 mg/L SM 2540 D Influent Total Suspended Solids 01/16/20 429 mg/L SM 2540 D Influent Total Suspended Solids 01/24/20 402 mg/L SM 2540 D Influent Total Suspended Solids 01/28/20 287 mg/L SM 2540 D Influent Total Suspended Solids 02/06/20 284 mg/L SM 2540 D Influent Total Suspended Solids 02/12/20 304 mg/L SM 2540 D Influent Total Suspended Solids 02/21/20 349 mg/L SM 2540 D Influent Total Suspended Solids 02/25/20 322 mg/L SM 2540 D Influent Total Suspended Solids 03/05/20 349 mg/L SM 2540 D Influent Total Suspended Solids 03/13/20 337 mg/L SM 2540 D Influent Total Suspended Solids 03/19/20 497 mg/L SM 2540 D Influent Total Suspended Solids 03/25/20 270 mg/L SM 2540 D Influent Total Suspended Solids 03/31/20 349 mg/L SM 2540 D Influent Total Suspended Solids 04/09/20 378 mg/L SM 2540 D Influent Total Suspended Solids 04/17/20 277 mg/L SM 2540 D Influent Total Suspended Solids 04/21/20 311 mg/L SM 2540 D Influent Total Suspended Solids 04/28/20 428 mg/L SM 2540 D Influent Total Suspended Solids 05/07/20 381 mg/L SM 2540 D Influent Total Suspended Solids 05/15/20 307 mg/L SM 2540 D Influent Total Suspended Solids 05/19/20 261 mg/L SM 2540 D Influent Total Suspended Solids 05/27/20 434 mg/L SM 2540 D Influent Total Suspended Solids 06/04/20 500 mg/L SM 2540 D Influent Total Suspended Solids 06/12/20 428 mg/L SM 2540 D Influent Total Suspended Solids 06/18/20 364 mg/L SM 2540 D Influent Total Suspended Solids 06/24/20 400 mg/L SM 2540 D Influent Total Suspended Solids 06/30/20 338 mg/L SM 2540 D Influent Total Suspended Solids 07/09/20 291 mg/L SM 2540 D Influent Total Suspended Solids 07/15/20 357 mg/L SM 2540 D Influent Total Suspended Solids 07/23/20 430 mg/L SM 2540 D Influent Total Suspended Solids 07/31/20 414 mg/L SM 2540 D Influent Total Suspended Solids 08/06/20 285 mg/L SM 2540 D Influent Total Suspended Solids 08/14/20 357 mg/L SM 2540 D Influent Total Suspended Solids 08/19/20 483 mg/L SM 2540 D Influent Total Suspended Solids 08/25/20 336 mg/L SM 2540 D Influent Total Suspended Solids 09/02/20 385 mg/L SM 2540 D Influent Total Suspended Solids 09/10/20 334 mg/L SM 2540 D Influent Total Suspended Solids 09/18/20 327 mg/L SM 2540 D Influent Total Suspended Solids 09/23/20 497 mg/L SM 2540 D Influent Total Suspended Solids 09/29/20 306 mg/L SM 2540 D Influent Total Suspended Solids 10/08/20 279 mg/L SM 2540 D Influent Total Suspended Solids 10/13/20 266 mg/L SM 2540 D Influent Total Suspended Solids 10/21/20 264 mg/L SM 2540 D Influent Total Suspended Solids 10/30/20 252 mg/L SM 2540 D Influent Total Suspended Solids 11/05/20 282 mg/L SM 2540 D Influent Total Suspended Solids 11/13/20 279 mg/L SM 2540 D Influent Total Suspended Solids 11/18/20 270 mg/L SM 2540 D Influent Total Suspended Solids 11/25/20 257 mg/L SM 2540 D Influent Total Suspended Solids 12/04/20 247 mg/L SM 2540 D Influent Total Suspended Solids 12/10/20 326 mg/L SM 2540 D Influent Total Suspended Solids 12/15/20 238 mg/L SM 2540 D City of Thousand Oaks
Hill Canyon Treatment Plant D-49 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Total Suspended Solids 12/22/20 256 mg/L SM 2540 D Influent Total Suspended Solids 12/29/20 232 mg/L SM 2540 D Influent Total Suspended Solids 01/07/21 283 mg/L SM 2540 D Influent Total Suspended Solids 01/12/21 253 mg/L SM 2540 D Influent Total Suspended Solids 01/22/21 222 mg/L SM 2540 D Influent Total Suspended Solids 01/27/21 249 mg/L SM 2540 D Influent Total Suspended Solids 02/05/21 254 mg/L SM 2540 D Influent Total Suspended Solids 02/10/21 244 mg/L SM 2540 D Influent Total Suspended Solids 02/18/21 216 mg/L SM 2540 D Influent Total Suspended Solids 02/23/21 250 mg/L SM 2540 D Influent Total Suspended Solids 03/05/21 228 mg/L SM 2540 D Influent Total Suspended Solids 03/11/21 228 mg/L SM 2540 D Influent Total Suspended Solids 03/17/21 221 mg/L SM 2540 D Influent Total Suspended Solids 03/23/21 236 mg/L SM 2540 D Influent Total Suspended Solids 03/31/21 244 mg/L SM 2540 D Influent Total Suspended Solids 04/08/21 305 mg/L SM 2540 D Influent Total Suspended Solids 04/16/21 232 mg/L SM 2540 D Influent Total Suspended Solids 04/20/21 313 mg/L SM 2540 D Influent Total Suspended Solids 04/28/21 272 mg/L SM 2540 D Influent Total Suspended Solids 05/06/21 252 mg/L SM 2540 D Influent Total Suspended Solids 05/14/21 308 mg/L SM 2540 D Influent Total Suspended Solids 05/19/21 296 mg/L SM 2540 D Influent Total Suspended Solids 05/25/21 263 mg/L SM 2540 D Influent Total Suspended Solids 06/04/21 302 mg/L SM 2540 D Influent Total Suspended Solids 06/10/21 268 mg/L SM 2540 D Influent Total Suspended Solids 06/17/21 321 mg/L SM 2540 D Influent Total Suspended Solids 06/23/21 264 mg/L SM 2540 D Influent Total Suspended Solids 06/29/21 278 mg/L SM 2540 D Influent Total Suspended Solids 07/08/21 292 mg/L SM 2540 D Influent Total Suspended Solids 07/14/21 277 mg/L SM 2540 D Influent Total Suspended Solids 07/22/21 274 mg/L SM 2540 D Influent Total Suspended Solids 07/30/21 276 mg/L SM 2540 D Influent Total Suspended Solids 08/05/21 244 mg/L SM 2540 D Influent Total Suspended Solids 08/13/21 317 mg/L SM 2540 D Influent Total Suspended Solids 08/19/21 284 mg/L SM 2540 D Influent Total Suspended Solids 08/25/21 296 mg/L SM 2540 D Influent Total Suspended Solids 08/31/21 181 mg/L SM 2540 D Influent Total Suspended Solids 09/09/21 277 mg/L SM 2540 D Influent Total Suspended Solids 09/14/21 241 mg/L SM 2540 D Influent Total Suspended Solids 09/24/21 215 mg/L SM 2540 D Influent Total Suspended Solids 09/29/21 240 mg/L SM 2540 D Influent Total Suspended Solids 10/07/21 230 mg/L SM 2540 D Influent Total Suspended Solids 10/12/21 201 mg/L SM 2540 D Influent Total Suspended Solids 10/21/21 225 mg/L SM 2540 D Influent Total Suspended Solids 10/28/21 207 mg/L SM 2540 D Influent Total Suspended Solids 11/05/21 266 mg/L SM 2540 D Influent Total Suspended Solids 11/10/21 284 mg/L SM 2540 D Influent Total Suspended Solids 11/18/21 290 mg/L SM 2540 D Influent Total Suspended Solids 11/24/21 292 mg/L SM 2540 D Influent Total Suspended Solids 11/30/21 335 mg/L SM 2540 D Influent Total Suspended Solids 12/09/21 246 mg/L SM 2540 D Influent Total Suspended Solids 12/17/21 94 mg/L SM 2540 D Sample result was excluded from analysis because it is an outlier.
Influent Total Suspended Solids 12/23/21 264 mg/L SM 2540 D Influent Total Suspended Solids 12/29/21 224 mg/L SM 2540 D Influent Total Suspended Solids 01/06/22 281 mg/L SM 2540 D Influent Total Suspended Solids 01/14/22 217 mg/L SM 2540 D Influent Total Suspended Solids 01/19/22 268 mg/L SM 2540 D Influent Total Suspended Solids 01/25/22 285 mg/L SM 2540 D Influent Total Suspended Solids 02/02/22 349 mg/L SM 2540 D Influent Total Suspended Solids 02/10/22 206 mg/L SM 2540 D City of Thousand Oaks
Hill Canyon Treatment Plant D-50 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Influent Total Suspended Solids 02/15/22 243 mg/L SM 2540 D Influent Total Suspended Solids 02/25/22 274 mg/L SM 2540 D Influent Total Suspended Solids 03/04/22 365 mg/L SM 2540 D Influent Total Suspended Solids 03/06/22 323 mg/L SM 2540 D Influent Total Suspended Solids 03/10/22 342 mg/L SM 2540 D Influent Total Suspended Solids 03/25/22 376 mg/L SM 2540 D Influent Total Suspended Solids 03/29/22 352 mg/L SM 2540 D Influent Total Suspended Solids 04/07/22 306 mg/L SM 2540 D Influent Total Suspended Solids 04/15/22 330 mg/L SM 2540 D Influent Total Suspended Solids 04/21/22 423 mg/L SM 2540 D Influent Total Suspended Solids 04/27/22 286 mg/L SM 2540 D Influent Total Suspended Solids 05/05/22 272 mg/L SM 2540 D Influent Total Suspended Solids 05/13/22 550 mg/L SM 2540 D Sample result was excluded from analysis because it is an outlier.
Influent Total Suspended Solids 05/19/22 356 mg/L SM 2540 D Influent Total Suspended Solids 05/25/22 450 mg/L SM 2540 D Influent Total Suspended Solids 06/02/22 263 mg/L SM 2540 D Influent Total Suspended Solids 06/09/22 286 mg/L SM 2540 D Influent Total Suspended Solids 06/17/22 272 mg/L SM 2540 D Influent Total Suspended Solids 06/22/22 292 mg/L SM 2540 D Influent Total Suspended Solids 06/30/22 288 mg/L SM 2540 D Influent Vanadium 06/01/22 5.8 1 0.32 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Vanadium 06/02/22 6 1 0.32 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Vanadium 06/03/22 6.4 1 0.32 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Vanadium 06/04/22 5.4 0.5 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Vanadium 06/05/22 6 0.5 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Vanadium 06/06/22 6.1 4 1.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Vanadium 06/07/22 5.6 0.5 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Zinc 08/08/19 160 ug/L EPA 200.8
Influent Zinc 02/06/20 130 ug/L EPA 200.8
Influent Zinc 08/06/20 180 ug/L EPA 200.8
Influent Zinc 02/18/21 170 ug/L EPA 200.8
Influent Zinc 08/05/21 130 ug/L EPA 200.8
Influent Zinc 02/10/22 140 ug/L EPA 200.8
Influent Zinc 06/01/22 130 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Zinc 06/02/22 150 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Zinc 06/03/22 140 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Zinc 06/04/22 110 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Zinc 06/05/22 130 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Zinc 06/06/22 150 80 13 ug/L EPA 200.8 Weck Laboratories, Inc.
Influent Zinc 06/07/22 140 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Ammonia as N 06/01/22 57 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Primary Effluent Ammonia as N 06/02/22 58 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Primary Effluent Ammonia as N 06/03/22 57 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Primary Effluent Ammonia as N 06/04/22 50 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Primary Effluent Ammonia as N 06/05/22 53 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Primary Effluent Ammonia as N 06/06/22 57 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Primary Effluent Ammonia as N 06/07/22 64 2.5 0.42 mg/L EPA 350.1 Weck Laboratories, Inc.
Primary Effluent Arsenic 06/01/22 4.4 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Arsenic 06/02/22 5.2 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Arsenic 06/03/22 5.1 0.8 0.15 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Arsenic 06/04/22 5.3 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Arsenic 06/05/22 5 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Arsenic 06/06/22 4.8 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Arsenic 06/07/22 4.2 0.4 0.074 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Cadmium 06/01/22 J 0.068 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Cadmium 06/02/22 < 0.084 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Cadmium 06/03/22 < 0.084 0.4 0.084 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Cadmium 06/04/22 J 0.067 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Cadmium 06/05/22 J 0.064 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Cadmium 06/06/22 J 0.091 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
City of Thousand Oaks
Hill Canyon Treatment Plant D-51 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Primary Effluent Cadmium 06/07/22 J 0.078 0.2 0.042 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Chloride 06/01/22 140 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Primary Effluent Chloride 06/02/22 140 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Primary Effluent Chloride 06/03/22 140 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Primary Effluent Chloride 06/04/22 140 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Primary Effluent Chloride 06/05/22 140 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Primary Effluent Chloride 06/06/22 140 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Primary Effluent Chloride 06/07/22 140 5 1.9 mg/L EPA 300.0 Weck Laboratories, Inc.
Primary Effluent Chromium 06/01/22 2.4 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Chromium 06/02/22 2.7 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Chromium 06/03/22 2.2 0.4 0.18 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Chromium 06/04/22 2.4 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Chromium 06/05/22 2.5 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Chromium 06/06/22 2.6 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Chromium 06/07/22 2.2 0.2 0.089 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Copper 06/01/22 25 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Copper 06/02/22 27 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Copper 06/03/22 27 1 0.46 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Copper 06/04/22 29 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Copper 06/05/22 31 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Copper 06/06/22 31 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Copper 06/07/22 28 0.5 0.23 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Cyanide 06/01/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Primary Effluent Cyanide 06/02/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Primary Effluent Cyanide 06/03/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Primary Effluent Cyanide 06/04/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Primary Effluent Cyanide 06/05/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Primary Effluent Cyanide 06/06/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Primary Effluent Cyanide 06/07/22 < 3.8 4 3.8 ug/L EPA 335.4 Weck Laboratories, Inc.
Primary Effluent Lead 06/01/22 0.4 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Lead 06/02/22 0.48 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Lead 06/03/22 0.44 0.4 0.17 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Lead 06/04/22 0.45 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Lead 06/05/22 0.45 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Lead 06/06/22 0.59 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Lead 06/07/22 0.41 0.2 0.083 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Mercury 06/01/22 0.013 0.0025 0.0005 ug/L EPA 1631E Weck Laboratories, Inc.
Primary Effluent Mercury 06/02/22 0.003 0.0005 0.0001 ug/L EPA 1631E Weck Laboratories, Inc.
Primary Effluent Mercury 06/03/22 0.018 0.0025 0.0005 ug/L EPA 1631E Weck Laboratories, Inc.
Primary Effluent Mercury 06/04/22 0.013 0.0025 0.0005 ug/L EPA 1631E Weck Laboratories, Inc.
Primary Effluent Mercury 06/05/22 0.012 0.0025 0.0005 ug/L EPA 1631E Weck Laboratories, Inc.
Primary Effluent Mercury 06/06/22 0.014 0.0025 0.0005 ug/L EPA 1631E Weck Laboratories, Inc.
Primary Effluent Mercury 06/07/22 0.019 0.0025 0.0005 ug/L EPA 1631E Weck Laboratories, Inc.
Primary Effluent Nickel 06/01/22 3.4 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Nickel 06/02/22 J 3.8 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Nickel 06/03/22 J 3.8 4 0.33 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Nickel 06/04/22 3.5 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Nickel 06/05/22 3.4 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Nickel 06/06/22 3.5 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Nickel 06/07/22 3.4 2 0.16 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Sulfide as S 06/01/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Primary Effluent Sulfide as S 06/02/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Primary Effluent Sulfide as S 06/03/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Primary Effluent Sulfide as S 06/04/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Primary Effluent Sulfide as S 06/05/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Primary Effluent Sulfide as S 06/06/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Primary Effluent Sulfide as S 06/07/22 < 0.05 0.1 0.05 mg/L SM 4500 S2-D Weck Laboratories, Inc.
Primary Effluent Zinc 06/01/22 72 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Zinc 06/02/22 77 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Zinc 06/03/22 74 20 3.3 ug/L EPA 200.8 Weck Laboratories, Inc.
City of Thousand Oaks
Hill Canyon Treatment Plant D-52 October 2023
Appendix D - Local Limits Data Summary
Sample Location Pollutant Sample
Date Result Reporting Limit Method
Detection Limit Units Analytical Method Analytical Laboratory Notes Primary Effluent Zinc 06/04/22 66 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Zinc 06/05/22 72 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Zinc 06/06/22 100 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
Primary Effluent Zinc 06/07/22 74 10 1.7 ug/L EPA 200.8 Weck Laboratories, Inc.
City of Thousand Oaks
Hill Canyon Treatment Plant D-53 October 2023
APPENDIX E
Local Limits Calculations
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 A B C D E
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration mg/L 63 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 4,200 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration mg/L 67 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 4,400 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration mg/L 57 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Concentration mg/L 1.5 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 110 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration mg/L 2.0 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 140 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration mg/L 75 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 4,941 8.34*(D4-D6)*D16 In-Plant Total Removal % 97.4% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % 10.2% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lbs/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids at Disposal Point % 63.5% 2021-2022 Monitoring Data Biosolids Density at Disposal Point kg/L 1.0 Estimated
Average Digester Concentration mg/L 830 2022 Local Limits Monitoring HCTP Design Capacity mg/L - -
Maximum Daily Discharge Limit mg/L 5.6 NPDES Permit Order No. R4-2019-0137 Weekly Average Discharge Limit mg/L - -
Monthly Average Discharge Limit mg/L 3.1 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit mg/L 480 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit mg/L - -
Anaerobic Digestion Inhibition Limit mg/L 1,500 USEPA Local Limits Guidance Manual HCTP Design Capacity Loading Limit lbs/day - -
Daily Discharge Loading Limit lbs/day 15,247 8.34*D5*D29/(1-D19) Weekly Average Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day 8,440 8.34*D5*D31/(1-D19) Activated Sludge Inhibition Loading Limit lbs/day 38,632 8.34*D4*D32/(1-D20) Nitrification Inhibition Limit Loading Limit lbs/day - - Anaerobic Digestion Inhibition Loading Limit lbs/day 7,590 D8*D34/D26 Headworks Limit lbs/day 7,590 MIN(D36:D42)
Basis of MAHL
Safety Factor 10% 759 C47*D44
Industrial Allocation lbs/day 1,890 D44-D17-D47
Uniform Local Limit mg/L 294 D48/D6/8.34
Maximum Allowable Industrial Loading (MAIL)
Existing Conditions (Wastewater)
Ammonia as N
Existing Conditions (Biosolids)
Removal Efficiency
Allowable Headworks Loading
Treatment/Discharge Limits
Maximum Allowable Headworks Loading (MAHL)
Anaerobic Digestion Inhibition Loading Limit
City of Thousand Oaks
Hill Canyon Treatment Plant E-1 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 F G H I J
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration mg/L 290 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 20,500 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration mg/L 387 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 31,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration mg/L - -
Average Final Effluent Concentration mg/L 1.8 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 130 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration mg/L 3.4 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 260 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration mg/L 340 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 22,401 8.34*(I4-I6)*I16 In-Plant Total Removal % 99.4% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % - -
Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lbs/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids at Disposal Point % 63.5% 2021-2022 Monitoring Data Biosolids Density at Disposal Point kg/L 1.0 Estimated
Average Digester Concentration mg/L - -
HCTP Design Capacity mg/L - -
Maximum Daily Discharge Limit mg/L 45 NPDES Permit Order No. R4-2019-0137 Weekly Average Discharge Limit mg/L 30 NPDES Permit Order No. R4-2019-0137 Monthly Average Discharge Limit mg/L 20 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit mg/L - -
Nitrification Inhibition Limit mg/L - -
Anaerobic Digestion Inhibition Limit mg/L - -
HCTP Design Capacity Loading Limit lbs/day 27,000 Plant Design Capacity Daily Discharge Loading Limit lbs/day 506,005 8.34*I5*I29/(1-I19) Weekly Average Discharge Loading Limit lbs/day 337,337 8.34*I5*I30/(1-I19) Monthly Average Discharge Loading Limit lbs/day 224,891 8.34*I5*I31/(1-I19) Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Limit Loading Limit lbs/day - - Anaerobic Digestion Inhibition Loading Limit lbs/day - - Headworks Limit lbs/day 27,000 MIN(I36:I42)
Basis of MAHL
Safety Factor 5% 1,350 H47*I44
Industrial Allocation lbs/day 3,249 I44-I17-I47
Uniform Local Limit mg/L 506 I48/I6/8.34
HCTP Design Capacity Loading Limit
Maximum Allowable Industrial Loading (MAIL)
Existing Conditions (Wastewater)
Biochemical Oxygen Demand (BOD)
Removal Efficiency
Allowable Headworks Loading
Treatment/Discharge Limits
Existing Conditions (Biosolids)
Maximum Allowable Headworks Loading (MAHL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-2 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 K L M N O
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration mg/L 130 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 8,800 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration mg/L 137 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 9,900 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration mg/L 140 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Concentration mg/L 140 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 9,800 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration mg/L 160 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 12,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration mg/L - -
Average Non-Industrial Loading lbs/day 8,100 Pollutant Mass Balance In-Plant Total Removal % -11.4% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % -7.7% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lbs/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids at Disposal Point % 63.5% 2021-2022 Monitoring Data Biosolids Density at Disposal Point kg/L 1.0 Estimated
Average Digester Concentration mg/L - -
HCTP Design Capacity mg/L - -
Maximum Daily Discharge Limit mg/L - -
Weekly Average Discharge Limit mg/L - -
Monthly Average Discharge Limit mg/L 150 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit mg/L - -
Nitrification Inhibition Limit mg/L 180 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit mg/L - -
HCTP Design Capacity Loading Limit lbs/day - -
Daily Discharge Loading Limit lbs/day - -
Weekly Average Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day 9,605 8.34*N5*N31/(1-N19) Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Limit Loading Limit lbs/day 12,086 8.34*N4*N33/(1-N20) Anaerobic Digestion Inhibition Loading Limit lbs/day - - Headworks Limit lbs/day 9,605 MIN(N36:N42)
Basis of MAHL
Safety Factor 5% 480 M47*N44
Industrial Allocation lbs/day 1,024 N44-N17-N47
Uniform Local Limit mg/L 160 N48/N6/8.34
Chloride
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Treatment/Discharge Limits
Allowable Headworks Loading
Maximum Allowable Headworks Loading (MAHL)
Monthly Average Discharge Loading Limit
Maximum Allowable Industrial Loading (MAIL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-3 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 P Q R S T
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration mg/L 110 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 7,700 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration mg/L 154 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 12,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration mg/L - -
Average Final Effluent Concentration mg/L 130 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 8,900 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration mg/L 175 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 12,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration mg/L 120 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 7,906 8.34*(S4-S6)*S16 In-Plant Total Removal % -15.6% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % - -
Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lbs/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids at Disposal Point % 63.5% 2021-2022 Monitoring Data Biosolids Density at Disposal Point kg/L 1.0 Estimated
Average Digester Concentration mg/L 200 Estimated
HCTP Design Capacity mg/L - -
Maximum Daily Discharge Limit mg/L - -
Weekly Average Discharge Limit mg/L - -
Monthly Average Discharge Limit mg/L 250 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit mg/L - -
Nitrification Inhibition Limit mg/L - -
Anaerobic Digestion Inhibition Limit mg/L 500 USEPA Local Limits Guidance Manual HCTP Design Capacity Loading Limit lbs/day - -
Daily Discharge Loading Limit lbs/day - -
Weekly Average Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day 15,423 8.34*S5*S31/(1-S19) Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Limit Loading Limit lbs/day - - Anaerobic Digestion Inhibition Loading Limit lbs/day 19,250 S8*S34/S26 Headworks Limit lbs/day 15,423 MIN(S36:S42)
Basis of MAHL
Safety Factor 10% 1,542 R47*S44
Industrial Allocation lbs/day 5,975 S44-S17-S47
Uniform Local Limit mg/L 930 S48/S6/8.34
Sulfate as SO4
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Treatment/Discharge Limits
Allowable Headworks Loading
Maximum Allowable Headworks Loading (MAHL)
Monthly Average Discharge Loading Limit
Maximum Allowable Industrial Loading (MAIL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-4 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 U V W X Y
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration mg/L 610 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 42,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration mg/L 690 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 55,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration mg/L - -
Average Final Effluent Concentration mg/L 610 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 42,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration mg/L 700 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 52,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration mg/L 630 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 41,508 8.34*(X4-X6)*X16 In-Plant Total Removal % 0% Zero Removal
In-Plant Primary Treatment Removal % - -
Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lbs/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids at Disposal Point % 63.5% 2021-2022 Monitoring Data Biosolids Density at Disposal Point kg/L 1.0 Estimated
Average Digester Concentration mg/L - -
HCTP Design Capacity mg/L - -
Maximum Daily Discharge Limit mg/L - -
Weekly Average Discharge Limit mg/L - -
Monthly Average Discharge Limit mg/L 850 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit mg/L - -
Nitrification Inhibition Limit mg/L - -
Anaerobic Digestion Inhibition Limit mg/L - -
HCTP Design Capacity Loading Limit lbs/day - -
Daily Discharge Loading Limit lbs/day - -
Weekly Average Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day 60,611 8.34*X5*X31/(1-X19) Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Limit Loading Limit lbs/day - - Anaerobic Digestion Inhibition Loading Limit lbs/day - - Headworks Limit lbs/day 60,611 MIN(X36:X42)
Basis of MAHL
Safety Factor 10% 6,061 W47*X44
Industrial Allocation lbs/day 13,042 X44-X17-X47
Uniform Local Limit mg/L 2,031 X48/X6/8.34
Total Dissolved Solids (TDS)
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Treatment/Discharge Limits
Allowable Headworks Loading
Maximum Allowable Headworks Loading (MAHL)
Monthly Average Discharge Loading Limit
Maximum Allowable Industrial Loading (MAIL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-5 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 Z AA AB AC AD
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration mg/L 300 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 22,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration mg/L 500 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 40,000 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration mg/L - -
Average Final Effluent Concentration mg/L 0.75 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 54 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration mg/L 1.6 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 140 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration mg/L 370 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 24,378 8.34*(AC4-AC6)*AC16 In-Plant Total Removal % 99.8% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % - -
Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lbs/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids at Disposal Point % 63.5% 2021-2022 Monitoring Data Biosolids Density at Disposal Point kg/L 1.0 Estimated
Average Digester Concentration mg/L - -
HCTP Design Capacity mg/L - -
Maximum Daily Discharge Limit mg/L 45 NPDES Permit Order No. R4-2019-0137 Weekly Average Discharge Limit mg/L 40 NPDES Permit Order No. R4-2019-0137 Monthly Average Discharge Limit mg/L 15 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit mg/L - -
Nitrification Inhibition Limit mg/L - -
Anaerobic Digestion Inhibition Limit mg/L - -
HCTP Design Capacity Loading Limit lbs/day 29,000 Plant Design Capacity Daily Discharge Loading Limit lbs/day 1,307,295 8.34*AC5*AC29/(1-AC19) Weekly Average Discharge Loading Limit lbs/day 1,162,040 8.34*AC5*AC30/(1-AC19) Monthly Average Discharge Loading Limit lbs/day 435,765 8.34*AC5*AC31/(1-AC19) Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Limit Loading Limit lbs/day - - Anaerobic Digestion Inhibition Loading Limit lbs/day - - Headworks Limit lbs/day 29,000 MIN(AC36:AC42)
Basis of MAHL
Safety Factor 5% 1,450 AB47*AC44
Industrial Allocation lbs/day 3,172 AC44-AC17-AC47
Uniform Local Limit mg/L 494 AC48/AC6/8.34
Total Suspended Solids (TSS)
Removal Efficiency
Existing Conditions (Wastewater)
Treatment/Discharge Limits
Existing Conditions (Biosolids)
Maximum Allowable Headworks Loading (MAHL)
Allowable Headworks Loading
Maximum Allowable Industrial Loading (MAIL)
HCTP Design Capacity Loading Limit
City of Thousand Oaks
Hill Canyon Treatment Plant E-6 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 A B C D E
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 4.8 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.33 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 6.6 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.43 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 4.9 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 3.3 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.22 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 4.2 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.29 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 2.6 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.17 0.00834*(D4-D6)*D16 In-Plant Total Removal % 33.3% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % -1.2% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L 100 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 1,500 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 1,600 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 41 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 500 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day 7.1 0.00834*D4*D30/(1-D20) Nitrification Inhibition Loading Limit lbs/day 107 0.00834*D4*D31/(1-D20) Anaerobic Digestion Inhibition Loading Limit lbs/day 2.5 0.00834*D22*D32/D19 Biosolids 40 CFR Part 503 Loading Limit lbs/day 1.4 0.000001*D23*D33/D19 Biosolids CCR Title 22 Loading Limit lbs/day 26 0.000001*D23*D34/D24/D19 Limiting MAHL lbs/day 1.4 MIN(D36:D42)
Basis of MAHL
Safety Factor 10% 0.14 C47*D44
Industrial Allocation lbs/day 1.1 D44-D17-D47
Uniform Local Limit mg/L 0.17 D48/D6/8.34
Arsenic
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Maximum Allowable Industrial Loading (MAIL)
Biosolids 40 CFR Part 503 Loading Limit
Treatment/Discharge/Disposal Limits
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-7 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 F G H I J
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 0.17 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.012 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 0.50 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.036 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 0.072 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 0.035 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.0025 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 0.078 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.0054 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 0.19 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.013 0.00834*(I4-I6)*I16 In-Plant Total Removal % 79.2% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % 57.6% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L 1,000 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 5,200 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 20,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 39 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 100 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day 171 0.00834*I4*I30/(1-I20) Nitrification Inhibition Loading Limit lbs/day 888 0.00834*I4*I31/(1-I20) Anaerobic Digestion Inhibition Loading Limit lbs/day 13 0.00834*I22*I32/I19 Biosolids 40 CFR Part 503 Loading Limit lbs/day 0.55 0.000001*I23*I33/I19 Biosolids CCR Title 22 Loading Limit lbs/day 2.2 0.000001*I23*I34/I24/I19 Limiting MAHL lbs/day 0.55 MIN(I36:I42)
Basis of MAHL
Safety Factor 10% 0.055 H47*I44
Industrial Allocation lbs/day 0.48 I44-I17-I47
Uniform Local Limit mg/L 0.075 I48/I6/8.34
Cadmium
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Biosolids 40 CFR Part 503 Loading Limit
Maximum Allowable Industrial Loading (MAIL)
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
Treatment/Discharge/Disposal Limits
City of Thousand Oaks
Hill Canyon Treatment Plant E-8 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 K L M N O
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 1.8 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.12 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 3.2 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.23 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 2.4 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 0.34 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.023 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 0.44 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.030 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 1.3 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.086 0.00834*(N4-N6)*N16 In-Plant Total Removal % 80.8% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % -33.3% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L 1,000 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 250 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 110,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg - - Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 500 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day 54 0.00834*N4*N30/(1-N20) Nitrification Inhibition Loading Limit lbs/day 14 0.00834*N4*N31/(1-N20) Anaerobic Digestion Inhibition Loading Limit lbs/day 72 0.00834*N22*N32/N19 Biosolids 40 CFR Part 503 Loading Limit lbs/day - -
Biosolids CCR Title 22 Loading Limit lbs/day 11 0.000001*N23*N34/N24/N19 Limiting MAHL lbs/day 11 MIN(N36:N42)
Basis of MAHL
Safety Factor 10% 1.1 M47*N44
Industrial Allocation lbs/day 10 N44-N17-N47
Uniform Local Limit mg/L 1.5 N48/N6/8.34
Chromium
Existing Conditions (Biosolids)
Existing Conditions (Wastewater)
Removal Efficiency
Maximum Allowable Industrial Loading (MAIL)
Biosolids CCR Title 22 Loading Limit
Treatment/Discharge/Disposal Limits
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-9 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 P Q R S T
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 42 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 2.9 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 54 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 3.8 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 28 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 3.3 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.23 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 9.0 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.65 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 42 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 2.8 0.00834*(S4-S6)*S16 In-Plant Total Removal % 92.1% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % 33.3% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L 9.0 NPDES Permit Order No. R4-2019-0137 Monthly Average Discharge Limit ug/L 6.0 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit ug/L 1,000 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 50 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 40,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 1,500 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 2,500 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day 8.1 0.00834*S5*S28/(1-S19) Monthly Average Discharge Loading Limit lbs/day 5.4 0.00834*S5*S29/(1-S19) Activated Sludge Inhibition Loading Limit lbs/day 108 0.00834*S4*S30/(1-S20) Nitrification Inhibition Loading Limit lbs/day 5.4 0.00834*S4*S31/(1-S20) Anaerobic Digestion Inhibition Loading Limit lbs/day 23 0.00834*S22*S32/S19 Biosolids 40 CFR Part 503 Loading Limit lbs/day 18 0.000001*S23*S33/S19 Biosolids CCR Title 22 Loading Limit lbs/day 48 0.000001*S23*S34/S24/S19 Limiting MAHL lbs/day 5.4 MIN(S36:S42)
Basis of MAHL
Safety Factor 10% 0.54 R47*S44
Industrial Allocation lbs/day 2.1 S44-S17-S47
Uniform Local Limit mg/L 0.33 S48/S6/8.34
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Copper
Maximum Allowable Industrial Loading (MAIL)
Monthly Average Discharge Loading Limit
Treatment/Discharge/Disposal Limits
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-10 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 U V W X Y
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 1.1 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.075 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 2.3 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.17 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 0.46 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 0.077 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.0051 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 0.12 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.0087 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 1.0 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.066 0.00834*(X4-X6)*X16 In-Plant Total Removal % 93.2% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % 58.2% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L 1,000 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 500 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 340,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 300 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 1,000 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day 173 0.00834*X4*X30/(1-X20) Nitrification Inhibition Loading Limit lbs/day 86 0.00834*X4*X31/(1-X20) Anaerobic Digestion Inhibition Loading Limit lbs/day 192 0.00834*X22*X32/X19 Biosolids 40 CFR Part 503 Loading Limit lbs/day 3.6 0.000001*X23*X33/X19 Biosolids CCR Title 22 Loading Limit lbs/day 19 0.000001*X23*X34/X24/X19 Limiting MAHL lbs/day 3.6 MIN(X36:X42)
Basis of MAHL
Safety Factor 10% 0.36 W47*X44
Industrial Allocation lbs/day 3.2 X44-X17-X47
Uniform Local Limit mg/L 0.49 X48/X6/8.34
Lead
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Maximum Allowable Industrial Loading (MAIL)
Biosolids 40 CFR Part 503 Loading Limit
Maximum Allowable Headworks Loading (MAHL)
Treatment/Discharge/Disposal Limits
Headworks Loading Limits
City of Thousand Oaks
Hill Canyon Treatment Plant E-11 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 Z AA AB AC AD
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 0.058 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.0039 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 0.18 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.012 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 0.013 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 0.00061 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.000038 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 0.0011 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.000071 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 0.060 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.0040 0.00834*(AC4-AC6)*AC16 In-Plant Total Removal % 99.0% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % 77.6% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L 0.0062 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit ug/L 100 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L - -
Anaerobic Digestion Inhibition Limit ug/L - -
Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 17 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 20 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day 0.045 0.00834*AC5*AC29/(1-AC19) Activated Sludge Inhibition Loading Limit lbs/day 32 0.00834*AC4*AC30/(1-AC20) Nitrification Inhibition Loading Limit lbs/day - -
Anaerobic Digestion Inhibition Loading Limit lbs/day - - Biosolids 40 CFR Part 503 Loading Limit lbs/day 0.19 0.000001*AC23*AC33/AC19 Biosolids CCR Title 22 Loading Limit lbs/day 0.36 0.000001*AC23*AC34/AC24/AC19 Limiting MAHL lbs/day 0.045 MIN(AC36:AC42)
Basis of MAHL
Safety Factor 10% 0.0045 AB47*AC44
Industrial Allocation lbs/day 0.037 AC44-AC17-AC47
Uniform Local Limit mg/L 0.0057 AC48/AC6/8.34
Mercury
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Maximum Allowable Industrial Loading (MAIL)
Treatment/Discharge/Disposal Limits
Monthly Average Discharge Loading Limit
Maximum Allowable Headworks Loading (MAHL)
Headworks Loading Limits
City of Thousand Oaks
Hill Canyon Treatment Plant E-12 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 AE AF AG AH AI
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 21 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 1.4 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 33 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 2.2 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L - -
Average Final Effluent Concentration ug/L 25 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 1.6 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 40 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 2.7 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 5.3 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.35 0.00834*(AH4-AH6)*AH16 In-Plant Total Removal % 15.2% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % - -
Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L - -
Nitrification Inhibition Limit ug/L - -
Anaerobic Digestion Inhibition Limit ug/L - -
Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 75 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 3,500 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Loading Limit lbs/day - -
Anaerobic Digestion Inhibition Loading Limit lbs/day - - Biosolids 40 CFR Part 503 Loading Limit lbs/day 5.5 0.000001*AH23*AH33/AH19 Biosolids CCR Title 22 Loading Limit lbs/day 407 0.000001*AH23*AH34/AH24/AH19 Limiting MAHL lbs/day 5.5 MIN(AH36:AH42)
Basis of MAHL
Safety Factor 10% 0.55 AG47*AH44
Industrial Allocation lbs/day 4.6 AH44-AH17-AH47
Uniform Local Limit mg/L 0.72 AH48/AH6/8.34
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
Biosolids 40 CFR Part 503 Loading Limit
Maximum Allowable Industrial Loading (MAIL)
Molybdenum
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Treatment/Discharge/Disposal Limits
City of Thousand Oaks
Hill Canyon Treatment Plant E-13 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 AJ AK AL AM AN
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 3.2 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.22 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 4.9 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.35 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 3.5 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 2.4 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.17 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 3.9 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.25 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 3.2 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.21 0.00834*(AM4-AM6)*AM16 In-Plant Total Removal % 22.7% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % -9.4% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L 231 NPDES Permit Order No. R4-2019-0137 Monthly Average Discharge Limit ug/L 153 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit ug/L 1,000 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 500 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 10,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 420 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 2,000 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day 21 0.00834*AM5*AM28/(1-AM19) Monthly Average Discharge Loading Limit lbs/day 14 0.00834*AM5*AM29/(1-AM19) Activated Sludge Inhibition Loading Limit lbs/day 66 0.00834*AM4*AM30/(1-AM20) Nitrification Inhibition Loading Limit lbs/day 33 0.00834*AM4*AM31/(1-AM20) Anaerobic Digestion Inhibition Loading Limit lbs/day 23 0.00834*AM22*AM32/AM19 Biosolids 40 CFR Part 503 Loading Limit lbs/day 21 0.000001*AM23*AM33/AM19 Biosolids CCR Title 22 Loading Limit lbs/day 155 0.000001*AM23*AM34/AM24/AM19 Limiting MAHL lbs/day 14 MIN(AM36:AM42)
Basis of MAHL
Safety Factor 10% 1.4 AL47*AM44
Industrial Allocation lbs/day 12 AM44-AM17-AM47
Uniform Local Limit mg/L 1.9 AM48/AM6/8.34
Nickel
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Maximum Allowable Industrial Loading (MAIL)
Monthly Average Discharge Loading Limit
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
Treatment/Discharge/Disposal Limits
City of Thousand Oaks
Hill Canyon Treatment Plant E-14 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 AO AP AQ AR AS
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 1.1 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.078 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 1.8 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.13 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L - -
Average Final Effluent Concentration ug/L 0.53 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.036 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 1.2 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.082 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 1.4 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.092 0.00834*(AR4-AR6)*AR16 In-Plant Total Removal % 53.8% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % - -
Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L - -
Nitrification Inhibition Limit ug/L - -
Anaerobic Digestion Inhibition Limit ug/L - -
Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 100 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 100 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Loading Limit lbs/day - -
Anaerobic Digestion Inhibition Loading Limit lbs/day - - Biosolids 40 CFR Part 503 Loading Limit lbs/day 2.1 0.000001*AR23*AR33/AR19 Biosolids CCR Title 22 Loading Limit lbs/day 3.3 0.000001*AR23*AR34/AR24/AR19 Limiting MAHL lbs/day 2.1 MIN(AR36:AR42)
Basis of MAHL
Safety Factor 10% 0.21 AQ47*AR44
Industrial Allocation lbs/day 1.8 AR44-AR17-AR47
Uniform Local Limit mg/L 0.28 AR48/AR6/8.34
Selenium
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Maximum Allowable Industrial Loading (MAIL)
Biosolids 40 CFR Part 503 Loading Limit
Treatment/Discharge/Disposal Limits
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-15 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 AT AU AV AW AX
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 0.23 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.016 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 0.36 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.024 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L - -
Average Final Effluent Concentration ug/L 0.012 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.00082 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 0.16 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.011 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 0.26 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.017 0.00834*(AW4-AW6)*AW16 In-Plant Total Removal % 94.9% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % - -
Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L - -
Nitrification Inhibition Limit ug/L - -
Anaerobic Digestion Inhibition Limit ug/L 13,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg - - Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 500 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day - -
Nitrification Inhibition Loading Limit lbs/day - -
Anaerobic Digestion Inhibition Loading Limit lbs/day 7.2 0.00834*AW22*AW32/AW19 Biosolids 40 CFR Part 503 Loading Limit lbs/day - -
Biosolids CCR Title 22 Loading Limit lbs/day 9.3 0.000001*AW23*AW34/AW24/AW19 Limiting MAHL lbs/day 7.2 MIN(AW36:AW42)
Basis of MAHL
Safety Factor 10% 0.72 AV47*AW44
Industrial Allocation lbs/day 6.5 AW44-AW17-AW47
Uniform Local Limit mg/L 1.0 AW48/AW6/8.34
Removal Efficiency
Existing Conditions (Biosolids)
Silver
Existing Conditions (Wastewater)
Treatment/Discharge/Disposal Limits
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
Anaerobic Digestion Inhibition Loading Limit
Maximum Allowable Industrial Loading (MAIL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-16 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
AY AZ BA BB BC
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 140 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 10 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 180 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 14 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 76 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 35 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 2.4 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 46 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 3.4 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 170 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 11 0.00834*(BB4-BB6)*BB16 In-Plant Total Removal % 75.8% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % 45.7% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L - -
Monthly Average Discharge Limit ug/L - -
Activated Sludge Inhibition Limit ug/L 300 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 80 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 400,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg 2,800 40 CFR Part 503 Biosolids CCR Title 22 Disposal Limit, Wet mg/kg 5,000 CCR Title 22 Maximum Daily Discharge Loading Limit lbs/day - -
Monthly Average Discharge Loading Limit lbs/day - -
Activated Sludge Inhibition Loading Limit lbs/day 40 0.00834*BB4*BB30/(1-BB20) Nitrification Inhibition Loading Limit lbs/day 11 0.00834*BB4*BB31/(1-BB20) Anaerobic Digestion Inhibition Loading Limit lbs/day 277 0.00834*BB22*BB32/BB19 Biosolids 40 CFR Part 503 Loading Limit lbs/day 41 0.000001*BB23*BB33/BB19 Biosolids CCR Title 22 Loading Limit lbs/day 116 0.000001*BB23*BB34/BB24/BB19 Limiting MAHL lbs/day 11 MIN(BB36:BB42)
Basis of MAHL
Safety Factor 10% 1.1 BA47*BB44
Industrial Allocation lbs/day (1.6) BB44-BB17-BB47
Existing Conditions (Wastewater)
Zinc
Existing Conditions (Biosolids)
Removal Efficiency
Headworks Loading Limits
Treatment/Discharge/Disposal Limits
Nitrification Inhibition Loading Limit
Maximum Allowable Headworks Loading (MAHL)
Maximum Allowable Industrial Loading (MAIL)
City of Thousand Oaks
Hill Canyon Treatment Plant E-17 October 2023
Appendix E - Local Limits Calculations
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 50
A B C D E
Units Calculations Formula/Source
Average HCTP Influent Flow mgd 8.67 July 2019-June 2022 Average Daily Influent Flow Average HCTP Effluent Flow mgd 8.55 July 2019-June 2022 Average Daily Effluent Flow Average Industrial Flow mgd 0.77 2022 Average Industrial Flow Average Influent Concentration ug/L 1.7 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Influent Loading lbs/day 0.12 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Concentration ug/L 1.9 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Influent Loading lbs/day 0.13 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Primary Effluent Concentration ug/L 3.8 2022 Local Limits Monitoring Average Final Effluent Concentration ug/L 2.2 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Final Effluent Load lbs/day 0.15 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Concentration ug/L 5.9 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Maximum Final Effluent Load lbs/day 0.41 June 2019-June 2022 Historical & 2022 Local Limits Monitoring Average Non-Industrial Concentration ug/L 3.8 2022 Local Limits Monitoring Average Non-Industrial Loading lbs/day 0.25 0.00834*(D4-D6)*D16 In-Plant Total Removal % 66% June 2019-June 2022 Historical & 2022 Local Limits Monitoring In-Plant Primary Treatment Removal % 27% 2022 Local Limits Monitoring Biosolids Flow to Digester mgd 0.063 2019-2022 Average Daily Biosolids Flow Biosolids Volume to Compost, Dry lb/day 11,200 2019-2021 Average Biosolids Disposal Volume Percent Solids of Biosolids % 63.5% 2021-2022 Monitoring Data Specific Gravity at Disposal Point kg/L 1.0 Estimated
Average Digester Concentration ug/L 3.7 Estimated
Average Biosolids Concentration, Dry mg/kg - -
Maximum Daily Discharge Limit ug/L 8.5 NPDES Permit Order No. R4-2019-0137 Monthly Average Discharge Limit ug/L 4.2 NPDES Permit Order No. R4-2019-0137 Activated Sludge Inhibition Limit ug/L 100 USEPA Local Limits Guidance Manual Nitrification Inhibition Limit ug/L 340 USEPA Local Limits Guidance Manual Anaerobic Digestion Inhibition Limit ug/L 1,000 USEPA Local Limits Guidance Manual Biosolids 40 CFR Part 503 Disposal Limit, Dry mg/kg - - Biosolids CCR Title 22 Disposal Limit, Wet mg/kg - -
Maximum Daily Discharge Loading Limit lbs/day 1.8 0.00834*D4*D29/(1-D19) Monthly Average Discharge Loading Limit lbs/day 0.89 0.00834*D4*D30/(1-D19) Activated Sludge Inhibition Loading Limit lbs/day 9.9 0.00834*D4*D31/(1-D20) Nitrification Inhibition Loading Limit lbs/day 34 0.00834*D4*D32/(1-D20) Anaerobic Digestion Inhibition Loading Limit lbs/day 32 D8*D33/D26 Biosolids 40 CFR Part 503 Loading Limit lbs/day - -
Biosolids CCR Title 22 Loading Limit lbs/day - -
Limiting MAHL lbs/day 0.89 MIN(D37:D43)
Basis of MAHL
Safety Factor 10% 0.089 C48*D45
Industrial Allocation lbs/day 0.55 D45-D17-D48
Uniform Local Limit mg/L 0.086 D49/D6/8.34
Maximum Allowable Industrial Loading (MAIL)
Cyanide
Existing Conditions (Wastewater)
Removal Efficiency
Existing Conditions (Biosolids)
Treatment/Discharge/Disposal Limits
Headworks Loading Limits
Maximum Allowable Headworks Loading (MAHL)
Monthly Average Discharge Loading Limit
City of Thousand Oaks
Hill Canyon Treatment Plant E-18 October 2023
APPENDIX F
Local Limits Calculations Documentation/
Assumptions
CITY OF THOUSAND OAKS October 2023 | F-1
HILL CANYON TREATMENT PLANT LOCAL LIMITS REPORT
This appendix lists the source of data and assumptions used in the derivation of the Hill Canyon Treatment Plant maximum allowable headworks loadings (MAHL), maximum allowable industrial loadings (MAIL), and local limits. Variations from these data sources and assumptions are noted on a pollutant-by-pollutant basis.
FOR ALL POLLUTANTS
• The July 2019 to June 2022 average daily influent flow was 8.67 million gallons per day (mgd).
• The July 2019 to June 2022 average daily effluent flow was 8.55 mgd. • The 2022 estimated average daily industrial user flow was 0.77 mgd. • Between 2019 and 2021, approximately 11,200 pounds per day (lbs/day dry weight) of biosolids were generated and disposed of at the composting facility. The average percent of biosolids was 63.5 percent.
• The July 2019 to June 2022 average biosolids disposal flow was 0.063 mgd. • Regression on order statistics (ROS) was used to estimate average pollutant concentrations and loads if there are sufficient detected data. If there were insufficient detected data to estimate the average using ROS, then the average was either calculated from detected data or the minimum reporting limit was utilized. • The activated sludge, nitrification, and anaerobic sludge digester inhibition levels from the 2004 Local Limits Guidance were used in the development of the local limits. The inhibition levels used in this study are presented in Appendix C. • Biosolids disposal limits from Title 40 of the Code of Federal Regulations (40 CFR) Part 503 were used, and presented in Appendix C.
• Biosolids disposal limits from Title 22 of the California Code of Regulations (CCR Title 22) were used, and presented in Appendix C.
• Effluent limitations were from the Waste Discharge Requirements for the City of Thousand Oaks Hill Canyon Treatment Plant (Order No. R4-2019-0137, NPDES No.
CA0056294), which was adopted by the Los Angeles Regional Water Quality Control Board in November 2019. These effluent limitations are presented in Appendix C. • Local limits sampling was conducted for the collection system, HCTP influent, HCTP primary treatment effluent, and HCTP final effluent in May and June 2022. Local limits sampling data were supplemented by historical data collected between July 2019 and June 2022.
• The collection system results obtained from composite samples on Days 4 through 6 were excluded from the analysis due to sampling error. It is believed that high amounts of sediment were collected leading to abnormal sampling results. • A 10 percent safety factor was used in calculating all MAILs.
CITY OF THOUSAND OAKS October 2023 | F-2
HILL CANYON TREATMENT PLANT LOCAL LIMITS REPORT
CONVENTIONAL POLLUTANTS
There were no pollutant-specific deviations from the assumptions discussed above for chloride, sulfate as SO4, and total dissolved solids (TDS). For ammonia as N, biochemical oxygen demand (BOD) and total suspended solids (TSS), see the following sections.
Ammonia as N
• Historical data for influent ammonia collected between July 2019 and June 2022 was not utilized in the development of the local limits since these data were obtained from composite samples instead of grab samples. Because ammonia can degrade due to biological activity in wastewater, the samples should be collected as grab samples.
Biochemical Oxygen Demand (BOD)
• The HCTP design capacity for BOD used for the local limit update was 27,000 lbs/day. • The influent samples collected on 3/19/2020 and 5/13/2022 were excluded from the analysis as outliers.
• The effluent sample collected 7/19/2019 was excluded from the analysis as an outlier. • A safety factor of 5 percent was used in the calculation of the MAIL and local limit because the HCTP is designed to remove BOD and includes additional safety factors as part of regular engineering design.
Chloride
• Collection system sample data resulted in a chloride load that significantly exceeded the average HCTP influent load, and was not used in this analysis. A mass balance using the average HCTP influent load and industrial user monitoring data was conducted to estimate the uncontrollable load. The estimated uncontrollable chloride load was 8,100 lbs/day.
• A safety factor of 5 percent was used in the calculation of the MAIL and local limit. The industrial user total chloride load was rounded up for the purposes of estimating the uncontrollable source contribution. This provides additional capacity and protection of HCTP and justifies the lower safety factor used in the MAIL and local limit calculations.
Total Suspended Solids (TSS)
• The HCTP design capacity for TSS used was 29,000 lbs/day. • The influent samples collected on 12/17/2021 and 5/13/2022 were excluded from the analysis as outliers.
• A safety factor of 5 percent was used in the calculation of the MAIL and local limit because the HCTP is designed to remove TSS and includes additional safety factors as part of regular engineering design.
CITY OF THOUSAND OAKS October 2023 | F-3
HILL CANYON TREATMENT PLANT LOCAL LIMITS REPORT
METALS (TOTAL RECOVERABLE)
There were no pollutant-specific deviations from the assumptions discussed above for arsenic, cadmium, lead, mercury, nickel, selenium, or zinc.
Chromium
• The collection system equipment blank result collected on 5/31/2022 was 5.2 ug/L. All collection system samples were qualified as non-detect at the reported result due to field blank sample contamination.
• The effluent chromium sample collected on 8/5/2022 was identified as an outlier and was excluded from the analysis.
Copper
• The effluent copper sample collected on 4/9/2020 was identified as an outlier and was excluded from the analysis.
Molybdenum
• The removal efficiency for molybdenum was calculated using Equation 5.4 of the Local Limits Guidance (Plant Removal Efficiency Calculated Using MRE and Sludge Data). The following data were used in the calculation:
o Average dry weather molybdenum concentration: 33.1 mg/kg (January 2020 to February 2023)
o Average percent solids: 63.5 percent (2021-2022)
o Sludge flowrate to disposal: 11,200 lbs/day (2019-2021) o Average influent flow: 8.67 mgd (July 2019 to June 2022) o Average influent concentration: 21.4 µg/L (2022 Local Limits Monitoring).
Silver
• The influent sample collected on 8/6/2020 was identified as an outlier and was excluded from the analysis.
• Due to the lack of detected samples results from the HCTP’s primary treatment effluent for this pollutant, the literature value for removal efficiency (obtained from Appendix R of the 2004 Local Limits Guidance) was utilized in the update of the City’s local limits. The primary treatment removal efficiency was 20 percent.
OTHER TOXICS
Cyanide
• The effluent sample collected on 8/4/2021 was identified as an outlier and was excluded from the analysis.
CITY OF THOUSAND OAKS October 2023 | F-4
HILL CANYON TREATMENT PLANT LOCAL LIMITS REPORT
• Since all of the primary treatment sample results and most of the influent sample results were not detected, the literature values for removal efficiency (obtained from Appendix R of the 2004 Local Limits Guidance) were utilized in the update of the City’s local limits.
The primary treatment removal efficiency was 27 percent and the HCTP removal efficiency was 66 percent.