NCSPPP
June
201
4 ESCP
Procedure
Page
8 SECTION
3 .
MODEL ESCP
TEMPLATE
1. Tracking Documentation
Official Use Only: Tracking Documentation
Permit Number:
ESCP Status
Date
ESCP Submittal Date:
☐
Approved:
Returned to Applicant for
Revision Date:
☐
Revise and Resubmit:
Submittal
Checked By:
ESCP Resubmittal Date:
☐
Modification Approved:
Resubmittal
Checked By:
☐
Modification Approved:
☐
Modification Approved:
2. Staff Comments
Official Use O
nly:
Reviewer Comments
Item
Comment
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Template
Page
9 3.
Project Information
Official Use Only
Applicant Complete this Section
Yes
No
Comments
A
☐
☐
☐
Project Name:
B
☐
☐
☐
Project
Number
:
C
☐
☐
☐
Assessor’s Parcel Number
:
D
☐
☐
☐
Location
:
E
☐
☐
☐
Name and Distance to
Nearest Receiving Water
:
F
☐
☐
☐
Area of Disturbance
:
(in acres or square feet)
G
☐
☐
☐
Total Project Size
:
(in acres or square feet)
H
☐
☐
☐
Planned
Project Start Date
:
I
☐
☐
☐
Planned Grading
Completion Date
:
J
☐
☐
☐
Planned Project
Completion Date
:
K
☐
☐
☐
Project Description and
Purpose
:
Capitola Subdivision
RSA+ Project No. 4123011.0
808 Capitola Drive, Napa CA 94559
Napa River, 2,400± feet
± 1.5 acre
TBD
TBD
TBD
046-020-020
The subdivision project consists of 8 new single-family lots/residences with an extension of Capitola Drive (public ROW), a new private street, and new utilities.
± 1.5 acres
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Template
3. Applicant Information
Official Use Only
Applicant Complete this Section
Yes
No
Comments
A
☐
☐
☐
Project Owner
Name:
☐
☐
☐
Address:
☐
☐
☐
Phone:
☐
☐
☐
Email:
B
☐
☐
☐
Contractor
Name:
☐
☐
☐
Address:
☐
☐
☐
Phone:
(24/7 Contact Number)
☐
☐
☐
Email:
C
☐
☐
☐
Applicant Certification
I certify that the information provided in the Erosion and Sediment Control Plan is, to the best of my knowledge and belief, true, accurate, and complete and that it will be implemented throughout the project. I further certify that I will notify the
City
of Napa CA
and submit revised information if any of
the information or conditions documented in this Erosion and Sediment Control Plan change. I understand there are significant penalties for submitting false information
or for not implement
ing
the
Erosion and Sediment Control Plan
per
NMC 8.36.00 Stormwater Runoff Pollution Control
. I will
retain a copy of the Erosion and Sediment Control Plan at the project site.
Signature:
Print/Type Name:
Title:
Date:
Derek Dittman
Project Manager, PE
March 20, 2025
MP Capitola Investor, LLC
620 Newport Center Drive, Suite 1100, Newport Beach, CA 92660 (949) 423-9496
[email protected]
TBD
TBD
TBD
TBD
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Template
Page
11 4. Identify Other
Permits or Controls Required
Identify whether other permits
or local controls
that affect water courses or water quality are required. Attach proof that the necessary permits have been applied for and obtained. Grading/Building P
ermits will not be
issued u
ntil proof is submitted that these other permits have been obtained
or that local controls have been
satisfied.
Official Use Only
Applicant Complete this Section
Yes
No
Comments
Permit/Agreement
Attached
A
☐
☐
☐
Construction General Permit (CGP)
☐
Not Applicable
☐
Applicable
☐
Proof of submission
☐
Proof permit was obtained
B
☐
☐
☐
Section 404 Permit
☐
Not Applicable
☐
Applicable
☐
Proof of submission
☐
Proof permit was obtained
C
☐
☐
☐
Section 401
Water Quality Certification
☐
Not Applicable
☐
Applicable
☐
Proof of submission
☐
Proof permit was obtained
D
☐
☐
☐
Streambed/Lake Alteration Agreement (1600 Agreements)
☐
Not Applicable
☐
Applicable
☐
Proof of submission
☐
Proof permit was obtained
E
☐
☐
☐
Napa County
Sensitive Domestic Water Supply Drainages
☐
Not Applicable
☐
Applicable
☐
Proof
requirements were
satisfied
F
☐
☐
☐
Other: (Identify)
List any specific permits required by the local,
state, federal, or regional agencies
☐
Proof of submission
☐
Proof permit was obtained
x
x
x
x
x
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Template
Page
12 5. Site Plan and BMP Implementation Schedule
Official Use Only
Applicant Complete this Section
Yes
No
Comments
A
☐
☐
☐
Site Plan
Attach site plan and l
ist relevant plan sheets depicting the
project site and
scope of construction.
Show any creek setbacks and areas where
existing
vegetation
will be preserved on the site plans.
B
☐
☐
☐
BMP Locations
Attach site plan and l
ist relevant plan sheets depicting locations of
and
types of
proposed BMPs. Some BMPs may be included as notes on the site plan.
C
☐
☐
☐
BMP Implementation
Schedule:
Identify schedule for BMP implementation with the commencement of the
construction activities and that BMPs will be implemented year round, as appropriate, until the project is complete. Include final site stabilization in the schedule.
The schedule may be shown on the site
plan(s) or as a separate document.
See Tentative Map plans.
See attached BMP implementation schedule.
BMPs are to be provided at locations described in the
sections below. A detailed plan sheet will be provided
with future improvement plans.
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Procedure
Page
13 6. BMP Information
Identify
and describe
the BMPs that will be implemented for the project. At a minimum, the ESCP must include the NCSPPP minimum erosion control, sediment control, and good housekeeping BMPs. Provide a rationale for the selected BMPs, including if needed, soil l oss calculations
. Use
the rationale to demonstrate that the selected control measures are appropriate site specific BMPs.
Official Use Only
Applicant Complete this Section
Yes
No
Comments
BMP
Rationale
EROSION CONTROL BMPS
A
☐
☐
☐
Preserve Existing
Vegetation
☐
☐
☐
☐
Yes
☐
Not Applicable
B
☐
☐
☐
Track Walk Slopes
☐
Yes
☐
Not Applicable
C
☐
☐
☐
Erosion Control Blankets or equivalent
☐
Yes
☐
Not Applicable
Site is to be cleared for the project development.
x
x
x
Provide slope stabilization with geotextiles and mat per EC-7 or other suitable methods.
Provide slope stabilization with track walking or other suitable methods.
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Procedure
Page
14 Official Use Only
Applicant Complete this Section
Yes
No
Comments
BMP
Rationale
D
☐
☐
☐
Soil Cover
☐
Yes
☐
Not Applicable
E
☐
☐
☐
Revegetation
☐
Yes
☐
Not Applicable
SEDIMENT CONTROL BMPS
F
☐
☐
☐
Stabilized Site Entrance
☐
Yes
☐
Not Applicable
G
☐
☐
☐
Fiber Rolls,
(e.g., Straw Wattles)
☐
Yes
☐
Not Applicable
Exposed soil shall be stabilized if not scheduled to be re-graded within 14 days per CASQA EC-04.
New vegetation will be provided per future landscape plans. Exposed soils not covered by structures, hardscape or landscaping shall be seeded or mulched per CASQA EC-3 and EC-4.
Project entrance shall be stabilized per CASQA TC-1 to prevent track-out.
Provide fiber rolls behind all curbs and back of sidewalk per CASQA SE-5 to mitigate potential transfer or sediment.
x
x
x
x
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Procedure
Page
15 Official Use Only
Applicant Complete this Section
Yes
No
Comments
BMP
Rationale
H
☐
☐
☐
Silt Fence
☐
Yes
☐
Not Applicable
I
☐
☐
☐
Drain Inlet Protection
☐
Yes
☐
Not Applicable
GOOD HOUSEKEEPING, MATERIALS AND WASTE MANAGEMENT BMPs
J
☐
☐
☐
Concrete Washout
☐
Yes
☐
Not Applicable
K
☐
☐
☐
Stockpile Management
☐
Yes
☐
Not Applicable
x
Provide silt fence per CASQA SE-1 around bioretention
facility to mitigate potential transfer of sediment.
x
Install drain inlet protection at all existing and proposed inlets per CASQA SE-10 to mitigate potential transfer of sediment.
Provide concrete washout per CASQA WM-8 near all concrete improvements including curbs, gutters, and sidewalks to contain concrete waste and mitigate potential runoff contamination.
Manage stockpiles per CASQA WM-3 as needed to contain excavation spoils and to mitigate sediment from stockpiles leaving the site. x
x
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Procedure
Page
16 Official Use Only
Applicant Complete this Section
Yes
No
Comments
BMP
Rationale
L
☐
☐
☐
Hazardous Material and Refuse Management
☐
Yes
☐
Not Applicable
M
☐
☐
☐
Sanitary Waste Management
☐
Yes
☐
Not Applicable
N
☐
☐
☐
Equipment and Vehicle Maintenance
☐
Yes
☐
Not Applicable
x
x
x
Manage refuse and hazardous waste per CASQA WM-6 for all oils, paints, coolants, etc. to mitigate potential runoff contamination.
Manage all temporary restrooms per CASQA WM-9 including secondary containment.
Maintenance of vehicles and equipment shall occur off site.
ATTACHMENT 7
Erosion and Sediment Control Plan
NCSPPP
June
201
4 ESCP
Procedure
Page
17 Official Use Only
Applicant Complete this Section
Yes
No
Comments
BMP
Rationale
Scheduling
O
☐
☐
☐
☐
Yes
☐
Not Applicable
Dust Control
☐
☐
☐
☐
Yes
☐
Not Applicable
Street Sweeping
☐
☐
☐
☐
Yes
☐
Not Applicable
☐
☐
☐
☐
Yes
☐
Not Applicable
Duplicate this page if needed to describe additional BMPs
x
x
Scheduling
Provide dust control per CASQA WE-1.
Sweep paved surfaces including streets, sidewalks
and gutters as needed per CASQA SE-7.
Construction activities shall be scheduled so as to minimize site disturbance and erosion/sediment potential as much as possible including sequencing of construction phases, coordination with weather, etc.
x
ATTACHMENT 7
Erosion and Sediment Control BMP Implementation Schedule 2047 Big Ranch Road, Napa CA
Erosion and Sediment Control
BMP Measures
Phase of Construction
Pre
-
Grading
(Clearing) Grading Utilities
Streets
(i.e. paving)
Vertical
Construction Landscaping
Site
Stabilization
Scheduling (EC
-
1)
X X X X X X X
Preservation of Existing
Vegetation (EC-2) X X X X X X X
Soil Stabilization (EC
-
3 -
7)
X X X X X X X
Stabilized Entrance (TC
-
1)
X X X X X X X
Silt Fence (SE
-
1)
X X X X X X X
Fiber
Rolls (SE
-
5)
X X X X X X X
Street Sweeping (SE
-
7)
X X X X X X X
Inlet Protection (SE
-
10)
X X X X X X X
Dust Control (WE
-
1)
X X X X X X X
Stockpile Management (WM
-
3)
X X X X X X X
Waste Management
(WM-5 & 6) X X X X X X X
Concrete Waste Management
(WM-8) X X X
Sanitary Waste
Management
(WM-9) X X X X X X X
Capitola Subdivision, Napa CA
ATTACHMENT 7
Scheduling
EC-1
Categories
EC
Erosion Control
;
SE
Sediment Control
:
TC
Tracking Control
:
WE
Wind Erosion Control
:
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Objective
:
Secondary Objective
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
Description and Purpose
Scheduling is the development of a written plan that includes sequencing of construction activities and the implementation of BMPs such as erosion control and sediment control while taking local climate (rainfall, wind, etc.) into consideration.
The purpose is to reduce the
amount and duration of soil
exposed to erosion by wind, rain, runoff, and vehicle tracking, and to perform the construction
activities and control practices
in accordance with the planned schedule.
Suitable Applications
Proper sequencing of construction
activities to reduce erosion
potential should be incorporated into the schedule of every construction project especially
during rainy season. Use of
other, more costly yet less e
ffective, erosion and sediment
control BMPs may often be
reduced through proper
construction sequencing.
Limitations
Environmental constraints such as nesting season
prohibitions reduce the full
capabilities of this BMP.
Implementation
Avoid rainy periods. Schedule major grading operations during dry months when practical. Allow enough time
before rainfall begins to stabil
ize the soil with vegetation or
physical means or to install sediment trapping devices.
Plan the project and develop a schedule showing each phase November 2009
California Stormwater BMP Handbook
1 of 3
Construction
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ATTACHMENT 7
Scheduling
EC-1
of construction. Clearly show
how the rainy season relates to soil disturbing and re- stabilization activities. Incorporate th
e construction schedule into the SWPPP.
Include on the schedule, details on the rain
y season implementation and deployment of:
-
Erosion control BMPs
-
Sediment control BMPs
-
Tracking control BMPs
-
Wind erosion control BMPs
-
Non-stormwater BMPs
-
Waste management and materials pollution control BMPs
Include dates for activities that may require no
n-stormwater discharges such as dewatering,
sawcutting, grinding, drilling, boring, crushing
, blasting, painting, hydro-demolition, mortar
mixing, pavement cleaning, etc.
Work out the sequencing and timetable for the star
t and completion of each item such as site
clearing and grubbing, grading, excavation, pavi
ng, foundation pouring utilities installation,
etc., to minimize the active construction area during the rainy season. -
Sequence trenching activities so that mo
st open portions are closed before new
trenching begins.
-
Incorporate staged seeding and re-vegetation of graded slopes as work progresses. -
Schedule establishment of permanent vegetati
on during appropriate planting time for
specified vegetation.
Non-active areas should be stabilized as s
oon as practical after
the cessation of soil
disturbing activities or one day pr
ior to the onset of precipitation.
Monitor the weather fo
recast for rainfall.
When rainfall is predicted, adju
st the construction schedule to allow the implementation of soil stabilization and sediment
treatment controls on all distur
bed areas prior to the onset of
rain.
Be prepared year round to deploy erosion co
ntrol and sediment control BMPs. Erosion may
be caused during dry seasons by un-seasonal ra
infall, wind, and vehicle tracking. Keep the
site stabilized year round, and retain and ma
intain rainy season sedi
ment trapping devices
in operational condition.
Apply permanent erosion control to areas de
emed substantially complete during the
project’s defined seeding window.
Costs
Construction scheduling to reduce erosion may in
crease other construction costs due to reduced
economies of scale in performing site grading.
The cost effectiveness of scheduling techniques
should be compared with the other less effective erosion and sedimentation controls to achieve a cost effective balance.
November 2009
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Construction
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ATTACHMENT 7
Scheduling
EC-1
November 2009
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Construction
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Inspection and Maintenance
Verify that work is progressing in accordance
with the schedule. If progress deviates, take
corrective actions.
Amend the schedule when changes are warranted.
Amend the schedule prior to the rainy seas
on to show updated information on the
deployment and implementation
of construction site BMPs.
References
Stormwater Quality Handbooks Co
nstruction Site Best Management Practices (BMPs) Manual, State of California Department of Tran
sportation (Caltrans), November 2000.
Stormwater Management for Construction Activiti
es Developing Pollution Prevention Plans and
Best Management Practices (EPA 832-R-92-005),
U.S. Environmental Protection Agency, Office
of Water, September 1992.
ATTACHMENT 7
Preservation Of Existing Vegetation EC-2
Categories
EC
Erosion Control
;
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Objective
:
Secondary Objective
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
Description and Purpose
Carefully planned preservation of
existing vegetation minimizes
the potential of removing or in
juring existing trees, vines,
shrubs, and grasses that protect soil from erosion.
Suitable Applications
Preservation of existing vegetation is suitable for use on most projects. Large project sites often provide the greatest opportunity for use of this BMP.
Suitable applications include
the following:
Areas within the site where no
construction activity occurs,
or occurs at a later date. This BMP is especially suitable to multi year projects where grading can be phased.
Areas where natural vegetation exists and is designated for preservation. Such areas often include steep slopes,
watercourse, and building sites in wooded areas.
Areas where local, state, and federal government require preservation, such as vernal pools, wetlands, marshes,
certain oak trees, etc. These areas are usually designated on the plans, or in the specifications, permits, or
environmental documents.
Where vegetation designated for ultimate removal can be temporarily preserved and be
utilized for erosion control
and sediment control.
Limitations
Requires forward planning by the owner/developer,
November 2009
California Stormwater BMP Handbook
1 of 4
Construction
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ATTACHMENT 7
Preservation Of Existing Vegetation EC-2
contractor, and design staff.
Limited opportunities for use when project plans do not incorporate existing vegetation into the site design.
For sites with diverse topography, it is often
difficult and expensive to save existing trees
while grading the site satisfacto
ry for the planned development.
Implementation
The best way to prevent erosion is to not disturb
the land. In order to reduce the impacts of new
development and redevelopment, pr
ojects may be designed to avoid disturbing land in sensitive areas of the site (e.g., natural watercourses, steep
slopes), and to incorporate unique or desirable
existing vegetation into the site’s landscaping plan. Clearly marking and leaving a buffer area around these unique areas during construction will
help to preserve these areas as well as take
advantage of natural erosion prevention and sediment trapping.
Existing vegetation to be preserved on the site
must be protected from mechanical and other
injury while the land is being de
veloped. The purpose of protecting existing vegetation is to ensure the survival of desirable vegetation fo
r shade, beautification, and erosion control.
Mature vegetation has extensive root systems that help to hold soil in place, thus reducing erosion. In addition, vegetation helps keep soil
from drying rapidly and becoming susceptible to
erosion. To effectively save ex
isting vegetation, no disturbances
of any kind should be allowed
within a defined area around the vegetation. Fo
r trees, no construction activity should occur
within the drip line of the tree.
Timing
Provide for preservation of existing vegetation prior to the commencement of clearing and grubbing operations or other soil
disturbing activities in areas
where no construction activity
is planned or will occur at a later date.
Design and Layout
Mark areas to be preserved with temporary fencing. Include sufficient setback to protect roots.
−
Orange colored plastic mesh fencing works well.
−
Use appropriate fence posts and adequate post
spacing and depth to completely support
the fence in an upright position.
Locate temporary roadways, stockpiles, and layo
ut areas to avoid stands of trees, shrubs,
and grass.
Consider the impact of grade changes to
existing vegetation and the root zone.
Maintain existing irrigation
systems where feasible. Temporar
y irrigation may be required.
Instruct employees and subcontractors to ho
nor protective devices. Prohibit heavy
equipment, vehicular traffic, or
storage of construction materi
als within the protected area.
November 2009
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Construction
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ATTACHMENT 7
Preservation Of Existing Vegetation EC-2
Costs
There is little cost associated wi
th preserving existing vegetation if properly planned during the project design, and these costs may be offset by ae
sthetic benefits that enhance property values.
During construction, the cost for preserving existing
vegetation will likely be
less than the cost of
applying erosion and sediment controls to
the disturbed area. Replacing vegetation
inadvertently destroyed during construction can
be extremely expensive,
sometimes in excess of
$10,000 per tree.
Inspection and Maintenance
During construction, the limits of disturbance
should remain clearly marked at all times.
Irrigation or maintenance of exis
ting vegetation should be descri
bed in the landscaping plan. If
damage to protected trees still occurs, mainte
nance guidelines described below should be
followed:
Verify that protective measures remain in
place. Restore damage
d protection measures
immediately.
Serious tree injuries shall be attended to by an arborist.
Damage to the crown, trunk, or root system of
a retained tree shall be repaired immediately.
Trench as far from tree trunks as possible, usually outside of the tree drip line or canopy.
Curve trenches around trees to avoid large roots or root concentrations. If roots are encountered, consider tunneling under them. When trenching or tunneling near or under trees to be retained, place tunnels at least 18
in. below the ground surface, and not below the
tree center to minimize impact on the roots.
Do not leave tree roots exposed to air. Cover ex
posed roots with soil as soon as possible. If
soil covering is not practical, protect exposed roots with wet burlap or peat moss until the tunnel or trench is ready for backfill.
Cleanly remove the ends of da
maged roots with a smooth cut.
Fill trenches and tunnels as soon as possible. Careful filling and tamping will eliminate air spaces in the soil, which can damage roots.
If bark damage occurs, cut back all loosened
bark into the undamaged area, with the cut
tapered at the top and bottom and drainage provided at the base of the wood. Limit cutting the undamaged area as much as possible.
Aerate soil that has been compacted over a tr
ees root zone by punching holes 12 in. deep
with an iron bar, and moving the bar back and fo
rth until the soil is loosened. Place holes 18
in. apart throughout the area of co
mpacted soil under the tree crown.
Fertilization
−
Fertilize stressed or damaged br
oadleaf trees to aid recovery.
−
Fertilize trees in the la
te fall or early spring.
November 2009
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Construction
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ATTACHMENT 7
Preservation Of Existing Vegetation EC-2
November 2009
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Construction
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-
Apply fertilizer to the soil over the feeder roots and in accordance with label instructions, but never closer than 3 ft to the trunk. Increase the fertilized area by one-fourth of the crown area for conifers that
have extended root systems.
Retain protective measures until all other constr
uction activity is complete to avoid damage
during site cleanup and stabilization.
References
County of Sacramento Tree Preservation Ordinance, September 1981.
Stormwater Quality Handbooks Co
nstruction Site Best Management Practices (BMPs) Manual, State of California Department of Tran
sportation (Caltrans), November 2000.
Stormwater Management of the Puget Sound Ba
sin, Technical Manual, Publication #91-75,
Washington State Department
of Ecology, February 1992.
Water Quality Management Plan for The Lake
Tahoe Region, Volume II, Handbook of
Management Practices, Tahoe Regional
Planning Agency, November 1988.
ATTACHMENT 7
Hydraulic Mulch
EC-3
November 2009
California Stormwater BMP Handbook
1 of 5
Construction
www.casqa.org
Description and Purpose
Hydraulic Mulch consists of vari
ous types of fibrous materials
mixed with water and sprayed onto
the soil surf
ace in slurry
form to provide a layer of temporary protection from wind and water erosion.
Suitable Applications
Hydraulic mulch as a temporary, stand alone, erosion control BMP is suitable for disturbed
areas that require temporary
protection from wind and wate
r erosion until permanent soil
stabilization activities commence. Examples include:
Rough-graded areas that will remain inactive for longer than permit-required thresholds (e.g., 14 days) or otherwise require stabilization to mi
nimize erosion or prevent
sediment discharges.
Soil stockpiles.
Slopes with exposed soil between existing vegetation such as trees or shrubs.
Slopes planted with live, co
ntainer-grown vegetation or
plugs.
Slopes burned by wildfire.
Hydraulic mulch can also be applied to augment other erosion control BMPs such as:
Categories
EC
Erosion Control
;
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
:
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
EC-4 Hydroseeding
EC-5 Soil Binders
EC-6 Straw Mulch
EC-7 Geotextiles and Mats
EC-8 Wood Mulching
EC-14 Compost Blanket
EC-16 Non-Vegetative Stabilization
ATTACHMENT 7
Hydraulic Mulch
EC-3
November 2009
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Construction
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In conjunction with straw mulch (see EC-6 St
raw Mulch) where the rate of hydraulic mulch
is reduced to 100-500 lbs per acre and the slur
ry is applied over the straw as a tackifying
agent to hold the straw in place.
Supplemental application
of soil amendments, such as fe
rtilizer, lime, gypsum, soil bio-
stimulants or compost.
Limitations
In general, hydraulic mulch
is not limited by slope length, gradient or soil type.
However, the
following limitations typically apply:
Most hydraulic mulch
applications, particularly bonded
fiber matrices (BFMs), require at
least 24 hours to dry before rainfall occurs.
Temporary applications (i.e., without a vege
tative component) may require a second
application in order to remain effe
ctive for an entire rainy season.
Treatment areas must be accessible to hydraulic mulching equipment.
Availability of water sources in remo
te areas for mixing and application.
As a stand-alone temporary BMP, hydraulic mulches may need to be re-applied to maintain their erosion control effectiveness, typically after 6-12 months depending on the type of mulch used.
Availability of hydraulic mulching equipment ma
y be limited just prior to the rainy season
and prior to storms due to high demand.
Cellulose fiber mulches alone may not perform we
ll on steep slopes or in course soils.
Implementation
Where feasible, it is preferable to prepare soil surfaces prior to application by roughening embankments and fill areas with a crimping or punching type roller or by track walking.
The majority of hydraulic mulch
applications do not necessa
rily require surface/soil
preparation (See EC-15 Soil Preparation) althou
gh in almost every case where re-vegetation
is included as part of the practice, soil prepar
ation can be beneficial. One of the advantages
of hydraulic mulch over other erosion control
methods is that it ca
n be applied in areas
where soil preparation is precluded by site cond
itions, such as steep slopes, rocky soils, or
inaccessibility.
Avoid mulch over spray onto roads, sidewalks,
drainage channels, existing vegetation, etc.
Hydraulic mulching
is generally performed utilizing spec
ialized machines that have a large
water-holding/mixing tank and some form of mechanical agitation or other recirculation method to keep water, mulch and soil amendments in suspension. The mixed hydraulic slurry can be applied from a tower sprayer on
top of the machine or by extending a hose to
areas remote from the machine.
ATTACHMENT 7
Hydraulic Mulch
EC-3
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3 of 5
Construction
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Where possible apply hydraulic mulch from multip
le directions to adequately cover the soil.
Application from a single direction can result
in shadowing, uneven co
verage and failure of
the BMP.
Hydraulic mulch can also include a vegetative co
mponent, such as seed
, rhizomes, or stolons
(see EC-4 Hydraulic Seed).
Typical hydraulic mulch application rates range from 2,000 pounds per acre for standard mulches (SMs) to 3,500 pounds per acre for
BFMs. However, the required amount of
hydraulic mulch to provide adequate coverage
of exposed topsoil may
appear to exceed the
standard rates when the roughness of the soil surface is changed due to soil preparation methods (see EC-15 Soil Preparat
ion) or by slope gradient.
Other factors such as existing soil moisture an
d soil texture can have
a profound effect on
the amount of hydraulic mulch required (i.e. a
pplication rate) applied to achieve an erosion-
resistant covering.
Avoid use of mulch without a tackifier component, especially on slopes.
Mulches used in the hydraulic mulch slurry can include:
-
Cellulose fiber
-
Thermally-processed wood fibers
-
Cotton
-
Synthetics
-
Compost (see EC-14, Compost Blanket)
Additional guidance on the comparison and
selection of temporary slope stabilization
methods is provided in Appe
ndix F of the Handbook.
Categories of Hydraulic Mulches
Standard Hydraulic Mulch (SM)
Standard hydraulic mulches are generally applied at a rate of 2,000 pounds per acre and are manufactured containing around 5% tackifier (i.e
. soil binder), usually a plant-derived guar or
psyllium type. Most standard mulches are green
in color derived from food-color based dyes.
Hydraulic Matrices (HM) and Stabilized Fiber Matrices (SFM)
Hydraulic matrices and stabilized fiber matrices are slurries which contain increased levels of tackifiers/soil binders; usually 10% or more by weight. HMs and SFMs have improved performance compared to a standard hydrau
lic mulch (SM) because of the additional
percentage of tackifier and because of their hi
gher application rates, typically 2,500 – 4,000
pounds per acre. Hydraulic matrices can include a mixture of fibers, for example, a 50/50 blend of paper and wood fiber. In the case of an SF
M, the tackifier/soil binder is specified as a
polyacrylamide (PAM).
ATTACHMENT 7
Hydraulic Mulch
EC-3
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4 of 5
Construction
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Bonded Fiber Matrix (BFM)
Bonded fiber matrices (BFMs) are hydraulically-a
pplied systems of fibers, adhesives (typically
guar based) and chemical cross-links. Upon
drying, the slurry forms an erosion-resistant
blanket that prevents soil erosion and promotes vegetation establishment. The cross-linked adhesive in the BFM should be
biodegradable and should not
dissolve or disperse upon re-
wetting. BFMs are typically applied at rates from 3,000 to 4,000 lbs/acre based on the manufacturer’s recommendation. BFMs should not be applied immediately before, during or immediately after rainfall or if
the soil is saturated. Depending on the product, BFMs typically require 12 to 24 hours to dry and become effective.
Mechanically-Bonded Fi
ber Matrices (MBFM)
Mechanically-bonded fiber matrices (MBFMs) ar
e hydraulically applied
systems similar to BFM
that use crimped synthetic fibers and PAM and
are typically applied to a slope at a higher
application rate than a standard BFM.
Hydraulic Compost Matrix (HCM)
Hydraulic compost matrix (HCM) is
a field-derived practice whereby finely graded or sifted compost is introduced into the hydraulic mulch
slurry. A guar-type tackifier can be added for
steeper slope applications as well as any specified seed mixtures. A HCM can help to accelerate seed germination and growth. HCMs are particular
ly useful as an in-fil
l for three-dimensional
re-vegetation geocomposites, such as turf reinforcement mats (TRM) (see EC-7 Geotextiles and Mats).
Costs
Average installed costs for hydraulic mulch categories are is provided in Table 1, below.
Table 1
HYDRAULIC MULCH BMPs
INSTALLED COSTS
BMP Installed
Cost/Acre
Standard Hydraulic Mulching (SM)
$1,700 - $3,600 per acre
Hydraulic Matrices (HM) and Stabilized Fiber Matrices
Guar-based
PAM-based
$2,000 - $4,000 per acre
$2,500 - $5,610 per acre
Bonded Fiber Matrix (BFM)
$3,900 - $6,900 per acre
Mechanically Bonded Fiber Matrix (MBFM)
$4,500 - $6,000 per acre
Hydraulic Compost Matrix (HCM)
$3,000 - $3,500 per acre
Source: Caltrans Soil Stabilization BMP Resear
ch for Erosion and Sediment Controls, July 2007
Inspection and Maintenance
Maintain an unbroken, temporary mulched
ground cover throughout the period of
construction when the soils are not being reworked.
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
ATTACHMENT 7
Hydraulic Mulch
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Construction
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weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Areas where erosion is evident should be repair
ed and BMPs re-applied as soon as possible.
Care should be exercised to mi
nimize the damage to protected
areas while making repairs, as
any area damaged will require re-application of BMPs.
Compare the number of bags or weight of applied mulch to the area treated to determine actual application rates and compliance with specifications.
References
Soil Stabilization BMP Research for Erosion an
d Sediment Controls: Cost Survey Technical
Memorandum, State of Californ
ia Department of Transportation (Caltrans), July 2007.
Controlling Erosion of Construction Sites, Agri
cultural Information #347, U.S. Department of
Agriculture (USDA), Natural
Resources Conservation Service (NRCS) (formerly Soil
Conservation Service – SCS).
Guides for Erosion and Sediment Control in Ca
lifornia, USDA Soils Conservation Service,
January 1991.
Manual of Standards of Erosion and Sediment
Control Measures, Association of Bay Area
Governments, May 1995.
Sedimentation and Erosion Control, An Inventor
y of Current Practices Draft, US EPA, April
1990.
Soil Erosion by Water, Agriculture Information Bu
lletin #513, U.S. Depart
ment of Agriculture,
Soil Conservation Service.
Stormwater Quality Handbooks Co
nstruction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.
Guidance Document: Soil Stabilization for Temporary Slopes, State of California Department of Transportation (Caltrans), November 1999
Stormwater Management of the Puget Sound Ba
sin, Technical Manual, Publication #91-75,
Washington State Department
of Ecology, February 1992.
Water Quality Management Plan for the Lake
Tahoe Region, Volume II, Handbook of
Management Practices, Tahoe Regional
Planning Agency, November 1988.
ATTACHMENT 7
Hydroseeding
EC-4
November 2009
California Stormwater BMP Handbook
1 of 4
Construction
www.casqa.org
Description and Purpose
Hydroseeding typically consists
of applying a mixture of a
hydraulic mulch, seed, fertilizer
, and stabilizing emulsion with
a hydraulic mulcher, to temporar
ily protect exposed soils from
erosion by water and wind. Hydraulic seeding, or
hydroseeding, is simply the method by which temporary or permanent seed is applied to the soil surface.
Suitable Applications
Hydroseeding is suitable fo
r disturbed areas requiring
temporary protection until permanent stabilization is
established, for disturbed areas that will be re-disturbed following an extended period of inactivity, or to apply permanent stabilization measures. Hydroseeding without mulch or other cover (e.g. EC-7,
Erosion Control Blanket) is not
a stand-alone erosion control
BMP and should be combined
with additional measures until vegetation establishment.
Typical applications for hydroseeding include:
Disturbed soil/graded areas where permanent stabilization or continued earthwork is not anticipated prior to seed germination.
Cleared and graded areas exposed to seasonal rains or
temporary irrigation.
Areas not subject to heavy wear by construction equipment or high traffic.
Categories
EC
Erosion Control
;
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
:
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
EC-3 Hydraulic Mulch
EC-5 Soil Binders
EC-6 Straw Mulch
EC-7 Geotextiles and Mats
EC-8 Wood Mulching
EC-14 Compost Blanket
EC-16 Non-Vegetative Stabilization
ATTACHMENT 7
Hydroseeding
EC-4
November 2009
California Stormwater BMP Handbook
2 of 4
Construction
www.casqa.org
Limitations
Availability of hydroseeding equipment may be
limited just prior to the rainy season and
prior to storms due to high demand.
Hydraulic seed should be applied with hy
draulic mulch or a stand-alone hydroseed
application should be followe
d by one of the following:
-
Straw mulch (see Straw Mulch EC-6)
-
Rolled erosion control products (see Geotextiles and Mats EC-7) -
Application of Compost Blanket
(see Compost Blanket EC-14)
Hydraulic seed may be used alone only on small flat surfaces when there is sufficient time in the season to ensure adequate vegetation establishment and coverage to provide adequate erosion control.
Hydraulic seed without mulch does not
provide immediate erosion control.
Temporary seeding may not be appropriate for stee
p slopes (i.e., slopes readily prone to rill
erosion or without sufficient topsoil).
Temporary seeding may not be appropriate in
dry periods without supplemental irrigation.
Temporary vegetation may have to be remove
d before permanent vege
tation is applied.
Temporary vegetation may not be appropriate fo
r short term inactivity (i.e. less than 3-6
months).
Implementation
In order to select appropriate hydraulic seed mixtur
es, an evaluation of site
conditions should be
performed with respect to:
-
Soil conditions
- Main
tenance requirements
-
Site topography and exposure (sun/wind) - Sensitive adjacent areas -
Season and climate
- Water availability
-
Vegetation types
- Plans
for permanent vegetation
The local office of the U.S.D.A. Natural Resources Conservation Service (NRCS) is an excellent source of information on appropriate seed mixes.
The following steps sh
ould be followed for implementation:
Where appropriate or feasible, soil should be prepared to receive the seed by disking or otherwise scarifying (See EC-15, Soil Preparatio
n) the surface to eliminate crust, improve air
and water infiltration and crea
te a more favorable environment for germination and growth.
ATTACHMENT 7
Hydroseeding
EC-4
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California Stormwater BMP Handbook
3 of 4
Construction
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Avoid use of hydraulic seed in areas where
the BMP would be incompatible with future
earthwork activities.
Hydraulic seed can be applied using a multiple step or one step process. -
In a multiple step process, h
ydraulic seed is applied first,
followed by mulch or a Rolled
Erosion Control Product (RECP).
-
In the one step process, hydraulic seed is
applied with hydraulic mulch in a hydraulic
matrix. When the one step process is used to apply the mixture of fiber, seed, etc., the seed rate should be increased to compensate
for all seeds not having
direct contact with
the soil.
All hydraulically seeded areas should have mulch, or alternate erosion control cover to keep seeds in place and to moderate soil moisture
and temperature until the seeds germinate and
grow.
All seeds should be in conformance with the California State Seed Law of the Department of Agriculture. Each seed bag should be delivered to the site sealed and clearly marked as to species, purity, percent germinat
ion, dealer's guarantee, and dates of test. The container should be labeled to clearly reflect the amount
of Pure Live Seed (PLS) contained. All
legume seed should be pellet inoculated. In
oculant sources should be species specific and
should be applied at a rate of 2
lb of inoculant per 100 lb seed.
Commercial fertilizer should conform to the requirements of the California Food and Agricultural Code, which can be found at
http://www.leginfo.ca.gov/.html/f
ac_table_of_contents.html. Fe
rtilizer should be pelleted
or granular form.
Follow up applications should be made as ne
eded to cover areas of poor coverage or
germination/vegetation esta
blishment and to maintain
adequate soil protection.
Avoid over spray onto roads, sidewalks, dr
ainage channels, existing vegetation, etc.
Additional guidance on the comparison and
selection of temporary slope stabilization
methods is provided in Appe
ndix F of the Handbook.
Costs
Average cost for installation an
d maintenance may vary from as
low as $1,900 per acre for flat
slopes and stable soils, to $4,0
00 per acre for moderate to steep slopes and/or erosive soils.
Cost of seed mixtures vary based
on types of required vegetation.
BMP
Installed
Cost per Acre
Hydraulic Seed
$1,900-$4,000
Source: Caltrans Soil Stabilization BMP Rese
arch for Erosion and Sediment Controls, July
2007
ATTACHMENT 7
Hydroseeding
EC-4
November 2009
California Stormwater BMP Handbook
4 of 4
Construction
www.casqa.org
Inspection and Maintenance
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Areas where erosion is evident should be repair
ed and BMPs re-applied as soon as possible.
Care should be exercised to minimize the damage to protected areas while making repairs, as
any area damaged will require re-application of BMPs.
Where seeds fail to germinate, or they germinate and die, the area must be re-seeded, fertilized, and mulched within the planting se
ason, using not less than half the original
application rates.
Irrigation systems, if applicable, should be in
spected daily while in use to identify system
malfunctions and line breaks. When line breaks are detected, the system must be shut down immediately and breaks repaired before
the system is put back into operation.
Irrigation systems should be inspected for co
mplete coverage and adjusted as needed to
maintain complete coverage.
References
Soil Stabilization BMP Research for Erosion an
d Sediment Controls: Cost Survey Technical
Memorandum, State of Californ
ia Department of Transportation (Caltrans), July 2007.
Stormwater Quality Handbooks Co
nstruction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.
Guidance Document: Soil Stabilization for Temporary Slopes, State of California Department of Transportation (Caltrans), November 1999.
ATTACHMENT 7
Straw Mulch
EC-6
November 2009
California Stormwater BMP Handbook
1 of 4
Construction
www.casqa.org
Description and Purpose
Straw mulch consists of placin
g a uniform layer of straw and
incorporating it into the soil with
a studded roller or crimper, or
anchoring it with a tackifier or
stabilizing emulsion. Straw
mulch protects the soil surface from the impact of rain drops, preventing soil particles from becoming dislodged.
Suitable Applications
Straw mulch is suitable for dist
urbed areas requiring temporary
protection until permanent stabil
ization is established. Straw
mulch can be specified for
the following applications:
As a stand-alone BMP on disturbed areas until soils can be prepared for permanent vegetation. The longevity of straw mulch is typically less than six months.
Applied in combination with
temporary seeding strategies
Applied in combination with
permanent seeding strategies
to enhance plant establishment and final soil stabilization
Applied around containerized plantings to control erosion until the plants become established to provide permanent stabilization
Limitations
Availability of straw and straw blowing equipment may be limited just prior to the rainy se
ason and prior to storms due
to high demand.
Categories
EC
Erosion Control
;
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
:
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
EC-3 Hydraulic Mulch
EC-4 Hydroseeding
EC-5 Soil Binders
EC-7 Geotextiles and Mats
EC-8 Wood Mulching
EC-14 Compost Blanket
ATTACHMENT 7
Straw Mulch
EC-6
November 2009
California Stormwater BMP Handbook
2 of 4
Construction
www.casqa.org
There is a potential for introduction of weed seed and unwanted plant material if weed-free agricultural straw
is not specified.
Straw mulch applied by hand is more
time intensive and potentially costly.
Wind may limit application of straw and
blow straw into undesired locations.
May have to be removed prior to permanen
t seeding or prior to further earthwork.
“Punching” of straw does not work in sandy
soils, necessitating the use of tackifiers.
Potential fugitive dust control issues asso
ciated with straw appl
ications can occur.
Application of a stabilizing emulsion or a water
stream at the same time straw is being blown
can reduce this problem.
Use of plastic netting should be avoided in areas where wildlife may be entrapped and may be prohibited for projects in certain areas with
sensitive wildlife species, especially reptiles
and amphibians.
Implementation
Straw should be derived from weed-free wheat, rice, or barley. Where required by the plans, specifications, permits, or environmental docu
ments, native grass straw should be used.
Use tackifier to anchor straw mulch to the soil on slopes.
Crimping, punch roller-type rollers, or track walking may also be used to incorporate straw mulch into the soil on slopes. Track walking can be used where other methods are impractical.
Avoid placing straw onto roads, sidewalks,
drainage channels, sound walls, existing
vegetation, etc.
Straw mulch with tackifier should not be appl
ied during or immediat
ely before rainfall.
Additional guidance on the comparison and
selection of temporary slope stabilization
methods is provided in Appe
ndix F of the Handbook.
Application Procedures
When using a tackifier to anchor the straw
mulch, roughen embankment or fill areas by
rolling with a crimping or punching-type roller or by track walking before placing the straw mulch. Track walking should only be used where rolling is impractical.
Apply straw at a rate of between 3,000 and 4,000 lb/acre, either by machine or by hand distribution and provide 100% ground cover. A
lighter application is used for flat surfaces
and a heavier application is used for slopes.
Evenly distribute straw mulch on the soil surface.
Anchoring straw mulch to the soil surface by
"punching" it into th
e soil mechanically
(incorporating) can be used in lieu of a tackifier.
ATTACHMENT 7
Straw Mulch
EC-6
November 2009
California Stormwater BMP Handbook
3 of 4
Construction
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Methods for holding the straw mulch in place de
pend upon the slope st
eepness, accessibility,
soil conditions, and longevity.
-
A tackifier acts to glue the straw fibers toge
ther and to the soil surface. The tackifier
should be selected based on longevity and ability
to hold the fibers in place. A tackifier is
typically applied at a rate of 125 lb/acre.
In windy conditions, the rates are typically 180
lb/acre.
-
On very small areas, a spade or shovel can be used to punch in straw mulch. -
On slopes with soils that are stable enough
and of sufficient gradient to safely support
construction equipment withou
t contributing to compaction
and instability problems,
straw can be "punched" into the ground using a knife blade roller or a straight bladed coulter, known commercially as a "crimper.”
Costs
Average annual cost for installation and maintenance is included in the table below. Application by hand is more time intensiv
e and potentially more costly.
BMP
Unit Cost per Acre
Straw mulch, crimped or punched
$2,458-$5,375
Straw mulch with tackifier
$1,823-$4,802
Source: Caltrans
Soil Stabilization BMP Research fo
r Erosion and Sediment Controls,
July 2007
Inspection and Maintenance
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Areas where erosion is evident should be repair
ed and BMPs re-applied as soon as possible.
Care should be exercised to mi
nimize the damage to protected
areas while making repairs, as
any area damaged will require re-application of BMPs.
The key consideration in inspec
tion and maintenance is that the straw needs to last long enough to achieve erosion control objectives. Straw mulch as a stand-alone BMP is temporary and is not suited for long-term erosion control.
Maintain an unbroken, temporary mulched gr
ound cover while disturbed soil areas are
inactive. Repair any damaged ground
cover and re-mulch exposed areas.
Reapplication of straw mulch an
d tackifier may be required
to maintain effective soil
stabilization over disturbed areas and slopes.
ATTACHMENT 7
Straw Mulch
EC-6
November 2009
California Stormwater BMP Handbook
4 of 4
Construction
www.casqa.org
References
Soil Stabilization BMP Research for Erosion an
d Sediment Controls: Cost Survey Technical
Memorandum, State of Californ
ia Department of Transportation (Caltrans), July 2007.
Erosion and Sediment Control Manual, Oregon De
partment of Environmental Quality, February
2005.
Controlling Erosion of Construction Sites,
Agricultural Information Bulletin #347, U.S.
Department of Agriculture (USD
A), Natural Resources Conservation Service (NRCS) (formerly Soil Conservation Service – SCS).
Guides for Erosion and Sediment Control in Ca
lifornia, USDA Soils Conservation Service,
January 1991.
Manual of Standards of Erosion and Sediment
Control Measures, Association of Bay Area
Governments, May 1995.
Soil Erosion by Water, Agricultural Information
Bulletin #513, U.S. Depa
rtment of Agriculture,
Soil Conservation Service.
Stormwater Quality Handbooks Co
nstruction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.
Stormwater Management of the Puget Sound Ba
sin, Technical Manual, Publication #91-75,
Washington State Department
of Ecology, February 1992.
Water Quality Management Plan for the Lake
Tahoe Region, Volume II, Handbook of
Management Practices, Tahoe Regional
Planning Agency, November 1988.
ATTACHMENT 7
Geotextiles and Mats
EC-7
November 2009
California Stormwater BMP Handbook
1 of 12
Construction
www.casqa.org
Description and Purpose
Mattings, or Rolled Erosion Control Products (RECPs), can be made of natural or synthetic ma
terials or a combination of the
two. RECPs are used to cover the soil surface to reduce erosion from rainfall impact, hold soil
in place, and absorb and hold
moisture near the soil surface. Additionally, RECPs may be used to stabilize soils until ve
getation is established or to
reinforce non-woody surface vegetation.
Suitable Applications
RECPs are typically applied on slopes where erosion hazard is high and vegetation will be slow to establish. Mattings are also used on stream banks, swales and other drainage channels where moving water at velocities between 3 ft/s and 6 ft/s are likely to cause scour and wash
out new vegetation, and in areas
where the soil surface is disturbed and where existing
vegetation has been removed.
RECPs may also be used when
seeding cannot occur (e.g., late
season construction and/or the
arrival of an early rain season). RECPs should be considered when the soils are fine grained and potentially erosive. RECPs should be considered in the following situations.
Steep slopes, generally steeper than 3:1 (H:V)
Slopes where the erosion potential is high
Slopes and disturbed soils where mulch must be anchored
Disturbed areas where plan
ts are slow to develop
Categories
EC
Erosion Control
;
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
:
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
EC-3 Hydraulic Mulch
EC-4 Hydroseeding
ATTACHMENT 7
Geotextiles and Mats
EC-7
November 2009
California Stormwater BMP Handbook
2 of 12
Construction
www.casqa.org
Channels with flows exceeding 3.3 ft/s
Channels to be vegetated
Stockpiles
Slopes adjacent to water bodies
Limitations
RECP installed costs are generally higher than other erosion control BM Ps, limiting their use
to areas where other BMPs are ineffe
ctive (e.g. channels, steep slopes).
RECPs may delay seed germination, due
to reduction in soil temperature.
RECPs are generally not suitable for excessively rocky sites or areas where the final vegetation will be mowed (since staples and netti
ng can catch in mowers). If a staple or pin
cannot be driven into the soil
because the underlying soil is
too hard or rocky, then an
alternative BMP should be selected.
If used for temporary erosion control, RECPs
should be removed and disposed of prior to
application of permanent so
il stabilization measures.
The use of plastic should be limited to coveri
ng stockpiles or very
small graded areas for
short periods of time (such as through
one imminent storm event) until more
environmentally friendly measures, such as
seeding and mulching, may be installed.
-
Plastic sheeting is easily vandalized, ea
sily torn, photodegradable, and must be
disposed of at a landfill.
-
Plastic sheeting results in 100% ru
noff, which may cause serious erosion
problems in the areas rece
iving the increased flow.
RECPs may have limitations based on soil type,
slope gradient, or channel flow rate; consult
the manufacturer for proper selection.
Not suitable for areas that have foot traffic (tripping hazard) – e.g., pad areas around buildings under construction.
RECPs that incorporate a plastic netting (e.g. st
raw blanket typically uses a plastic netting to
hold the straw in place) may not be suitable
near known wildlife habitat. Wildlife can
become trapped in the plastic netting.
RECPs may have limitations in extremely windy climates. However, when RECPs are properly trenched at the top and bottom and stapled in accordance with the manufacturer’s recommendations, problems with wind can be minimized.
ATTACHMENT 7
Geotextiles and Mats
EC-7
November 2009
California Stormwater BMP Handbook
3 of 12
Construction
www.casqa.org
Implementation
Material Selection
Natural RECPs have been found to be effective where re-vegetation will be provided by re- seeding. The choice of material should be based on the size of area, side slopes, surface conditions such as hardness, moisture, weed
growth, and availabi
lity of materials.
Additional guidance on the comparison and
selection of temporary slope stabilization
methods is provided in Appe
ndix F of the Handbook.
The following natural and synth
etic RECPs are commonly used:
Geotextiles
Material can be a woven or a non-woven polypropylene fabric with minimum thickness of
0.06 in., minimum width of 12 ft and should have minimum tensile strength of 150 lbs (warp), 80 lbs (fill) in confor
mance with the requirements in ASTM Designation: D 4632.
The permittivity of the fabric sh
ould be approximately 0.07 sec
–1
in conformance with the
requirements in ASTM Designation: D4491.
The fabric should have an ultraviolet (UV)
stability of 70 percent in conf
ormance with the requirements in ASTM designation: D4355.
Geotextile blankets must be secured in place
with wire staples or sandbags and by keying
into tops of slopes to prevent infiltration of
surface waters under geot
extile. Staples should
be made of minimum 11 gauge steel wire and sh
ould be U-shaped with 8 in. legs and 2 in.
crown.
Geotextiles may be reused if they are suitable for the use intended.
Plastic Covers
Generally plastic sheeting should only be used
as stockpile covering or
for very small graded
areas for short periods of time (such as th
rough one imminent stor
m event). If plastic
sheeting must be used, choose a plastic th
at will withstand photo degradation.
Plastic sheeting should have a minimum thicknes
s of 6 mils, and must be keyed in at the top
of slope (when used as a temporary slope protec
tion) and firmly held in place with sandbags
or other weights placed no more than 10 ft apart. Seams are typically taped or weighted down their entire length, and there should be at
least a 12 in. to 24 in. overlap of all seams.
Edges should be embedded a minimum of 6 in
. in soil (when used as a temporary slope
protection).
All sheeting must be inspected periodically afte
r installation and after significant rainstorms
to check for erosion, undermining, and anchorag
e failure. Any failur
es must be repaired
immediately. If washout or breakages occur,
the material should be re-installed after
repairing the damage to the slope.
Erosion Control Blankets/Mats
Biodegradable RECPs are typically composed of
jute fibers, curled wood fibers, straw,
coconut fiber, or a combination of these material
s. In order for an RECP to be considered
100% biodegradable, the netting, sewing or
adhesive system that ho
lds the biodegradable
mulch fibers together must also be biodegradable. See typical installation details at the end of this fact sheet.
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-
Jute
is a natural fiber that is made into a yarn
that is loosely woven into a biodegradable
mesh. The performance of jute as a stan
d-alone RECP is low.
Most other RECPs
outperform jute as a temporary erosion co
ntrol product and therefore jute is not
commonly used. It is designed to be used in
conjunction with vegetation. The material
is supplied in rolled strips, wh
ich should be secured to the so
il with U-shaped staples or
stakes in accordance with manufacturers’ recommendations. -
Excelsior
(curled wood fiber) blanket material
should consist of machine produced
mats of curled wood excelsior with 80 percent of the fiber 6 in. or longer. The excelsior blanket should be of consistent thickness.
The wood fiber must be evenly distributed
over the entire area of the blanket. The top
surface of the blanket should be covered with
a photodegradable extruded plastic mesh.
The blanket should be smolder resistant
without the use of chemical additives and should be non-toxic and non-injurious to plant and animal life. Excelsior blankets should be
furnished in rolled strips, a minimum of 48
in. wide, and should have an average weight of 0.8 lb/yd 2 ,
±
10 percent, at the time of
manufacture. Excelsior blankets must be se
cured in place with wire staples. Staples
should be made of minimum 11 gauge steel wire
and should be U-shaped with 8 in. legs
and 2 in. crown.
-
Straw blanket
should be machine produced ma
ts of straw with a lightweight
biodegradable netting top layer. The straw
should be attached to the netting with
biodegradable thread or glue strips. The straw
blanket should be of consistent thickness.
The straw should be evenly distributed over the entire area of the blanket. Straw blanket should be furnished in rolled strips a minimu
m of 6.5 ft wide, a minimum of 80 ft long
and a minimum of 0.5 lb/yd
2 . Straw blankets must be secure
d in place with wire staples.
Staples should be made of minimum 11 gauge
steel wire and should be U-shaped with 8
in. legs and 2 in. crown.
-
Wood fiber blanket
is composed of biodegradable fiber mulch with extruded plastic netting held together with adhesives. The material is designed to enhance re-vegetation.
The material is furnished in rolled strips,
which must be secured to the ground with U-
shaped staples or stakes in accordance
with manufacturers’ recommendations.
-
Coconut fiber blanket
should be a machine produced
mat of 100 percent coconut
fiber with biodegradable netting on the top
and bottom. The coconut fiber should be
attached to the netting with biodegradable
thread or glue strips. The coconut fiber
blanket should be of consistent thickness.
The coconut fiber should be evenly distributed
over the entire area of the blanket. Coconu
t fiber blanket should be furnished in rolled
strips with a minimum of 6.5 ft wide, a mi
nimum of 80 ft. long and a minimum of 0.5
lb/yd
2 . Coconut fiber blankets must be secure
d in place with wire staples. Staples
should be made of minimum 11 gauge steel wire
and should be U-shaped with 8 in. legs
and 2 in. crown.
-
Coconut fiber mesh
is a thin permeable membrane made from coconut or corn fiber that is spun into a yarn and woven into a biodeg
radable mat. It is designed to be used in
conjunction with vegetation and typically has lo
ngevity of several years. The material is
supplied in rolled strips, which must be secu
red to the soil with U-shaped staples or
stakes in accordance with manufacturers’ recommendations.
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Straw coconut fiber blanket
should be machine produced
mats of 70 percent straw
and 30 percent coconut fiber with a biodegradable netting top layer and a biodegradable bottom net. The straw and coconut fiber sh
ould be attached to the netting with
biodegradable thread or glue strips. The
straw coconut fiber blanket should be of
consistent thickness. The straw and coconut fiber should be evenly distributed over the entire area of the blanket. Straw coconut
fiber blanket should be furnished in rolled
strips a minimum of 6.5 ft wide, a minimum
of 80 ft long and a minimum of 0.5 lb/yd
2 .
Straw coconut fiber blankets must
be secured in place with wi
re staples. Staples should
be made of minimum 11 gauge steel wire and sh
ould be U-shaped with 8 in. legs and 2 in.
crown.
Non-biodegradable RECPs are typically composed
of polypropylene, po
lyethylene, nylon or
other synthetic fibers. In some cases, a combin
ation of biodegradable and synthetic fibers is
used to construct the RECP. Netting used to
hold these fibers together is typically non-
biodegradable as well.
-
Plastic netting
is a lightweight biaxially oriented
netting designed for securing loose
mulches like straw or paper to soil surfaces
to establish vegetation. The netting is
photodegradable. The netting
is supplied in rolled strips,
which must be secured with U-
shaped staples or stakes in accordance
with manufacturers’ recommendations.
-
Plastic mesh
is an open weave geotextile that is
composed of an extruded synthetic
fiber woven into a mesh with an opening size
of less than ¼ in. It is used with re-
vegetation or may be used to
secure loose fiber such as straw to the ground. The material is supplied in rolled strips, wh
ich must be secured to the so
il with U-shaped staples or
stakes in accordance with manufacturers’ recommendations. -
Synthetic fiber with netting
is a mat that is composed of durable synthetic fibers
treated to resist chemicals and ultraviolet li
ght. The mat is a dense, three dimensional
mesh of synthetic (typically polyolefin) fibe
rs stitched between two polypropylene nets.
The mats are designed to be re-vegetated and provide a permanent composite system of soil, roots, and geomatrix. The material is
furnished in rolled strips, which must be
secured with U-shaped staples or stakes
in accordance with manufacturers’
recommendations.
-
Bonded synthetic fibers
consist of a three dimensional geomatrix nylon (or other synthetic) matting. Typically it has more th
an 90 percent open area, which facilitates
root growth. It’s tough root reinforcing sy
stem anchors vegetation and protects against
hydraulic lift and shear forces created by hi
gh volume discharges. It can be installed
over prepared soil, followed by seeding into the mat. Once vegetated, it becomes an invisible composite system of soil, roots, an
d geomatrix. The material is furnished in
rolled strips that must be se
cured with U-shaped staples or
stakes in accordance with
manufacturers’ recommendations.
-
Combination synthetic and biodegradable RECPs
consist of biodegradable fibers,
such as wood fiber or coconu
t fiber, with a heavy polypropylene net stitched to the top and a high strength continuous filament geom
atrix or net stitched to the bottom. The
material is designed to enhance re-vegetation. The material is furnished in rolled strips, ATTACHMENT 7
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which must be secured with U-shaped st
aples or stakes in accordance with
manufacturers’ recommendations.
Site Preparation
Proper soil preparation is essential to ensure co
mplete contact of the RE
CP with the soil. Soil
Roughening is not recommended in ar
eas where RECPs wi
ll be installed.
Grade and shape the area of installation.
Remove all rocks, clods, vegeta
tion or other obstructions so
that the installed blankets or
mats will have complete, di
rect contact with the soil.
Prepare seedbed by loosening 2 to 3 in. of topsoil.
Seeding/Planting
Seed the area before blanket installation for erosion control and re-vegetation. Seeding after mat installation is often specif
ied for turf reinforcement applic
ation. When seeding prior to
blanket installation, all areas disturbed during bl
anket installation must be re-seeded. Where
soil filling is specified for turf reinforcemen
t mats (TRMs), seed the matting and the entire
disturbed area after installation and
prior to filling the mat with soil.
Fertilize and seed in accordance
with seeding specifications or ot
her types of landscaping plans.
The protective matting can be laid over areas where grass has been planted and the seedlings have emerged. Where vines or other ground covers are to be planted, lay the protective matting first and then plant through matting according to design of planting.
Check Slots
Check slots shall be installed as
required by the manufacturer.
Laying and Securing Matting
Before laying the matting, all check slots shou
ld be installed and the seedbed should be
friable, made free from clods, rocks, and
roots. The surface should be compacted and
finished according to the requirements
of the manufacturer’s
recommendations.
Mechanical or manual lay down equipment should be capable of handling full rolls of fabric and laying the fabric smoothly without wrinkles
or folds. The equipment should meet the
fabric manufacturer’s recommenda
tions or equivalent standards.
Anchoring
U-shaped wire staples, metal ge
otextile stake pins, or triangul
ar wooden stakes can be used
to anchor mats and blankets to the ground surface.
Wire staples should be made of minimum 11 gaug
e steel wire and should be U-shaped with 8
in. legs and 2 in. crown.
Metal stake pins should be 0.188 in. diameter st
eel with a 1.5 in. steel washer at the head of
the pin, and 8 in. in length.
Wire staples and metal stakes should be
driven flush to the soil surface.
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Installation on Slopes
Installation should be in acco
rdance with the manufacturer's recommendations. In general, these will be as follows:
Begin at the top of the slope and anchor the blanket in a 6 in. deep by 6 in. wide trench.
Backfill trench and tamp earth firmly.
Unroll blanket down slope in the direction of water flow.
Overlap the edges of adjacent parallel rolls 2 to
3 in. and staple every 3 ft (or greater, per
manufacturer’s specifications).
When blankets must be spliced, place blankets end over end (shingle style) with 6 in. overlap. Staple through overlapped area, approximately 12 in. apart.
Lay blankets loosely and maintain direct
contact with the soil
. Do not stretch.
Staple blankets sufficiently to anchor blanket
and maintain contact with the soil. Staples
should be placed down the center and staggere
d with the staples placed along the edges.
Steep slopes, 1:1 (H:V) to 2:1 (H:V),
require a minimum of 2 staples/yd
2 . Moderate slopes,
2:1 (H:V) to 3:1 (H:V), requir
e a minimum of 1 ½ staples/yd
2 . Check manufacturer’s
specifications to determine if a higher
density staple pattern is required.
Installation in Channels
Installation should be in acco
rdance with the manufacturer's recommendations. In general, these will be as follows:
Dig initial anchor trench 12 in. deep and 6 in. wide across the channel at the lower end of the project area.
Excavate intermittent check slots, 6 in. deep an
d 6 in. wide across the ch
annel at 25 to 30 ft
intervals along the channels.
Cut longitudinal channel anchor
trenches 4 in. deep and 4 in.
wide along each side of the
installation to bury edges of matting, whenever possible extend matting 2 to 3 in. above the crest of the channel side slopes.
Beginning at the downstream end and in the center of the channel, place the initial end of the first roll in the anchor trench and secure wi
th fastening devices at 12 in. intervals. Note:
matting will initially be upsi
de down in anchor trench.
In the same manner, position adjacent rolls in anchor trench, overlapping the preceding roll a minimum of 3 in.
Secure these initial ends of mats with anchors
at 12 in. intervals, backfill and compact soil.
Unroll center strip of matting upstream. Stop at
next check slot or terminal anchor trench.
Unroll adjacent mats upstream in simila
r fashion, maintaining a 3 in. overlap.
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Fold and secure all rolls of matting snugly into all transverse check slots. Lay mat in the bottom of the slot then fold back against itself.
Anchor through both layers of mat at 12 in.
intervals, then backfill and compact soil. Continue rolling all mat widths upstream to the next check slot or terminal anchor trench.
Alternate method for non-critical
installations: Place two rows of anchors on 6 in. centers at 25 to 30 ft. intervals in li
eu of excavated check slots.
Staple shingled lap spliced ends a minimu
m of 12 in. apart on 12 in. intervals.
Place edges of outside mats in previously
excavated longitudinal
slots; anchor using
prescribed staple pattern, backfill, and compact soil.
Anchor, fill, and compact upstream end of ma
t in a 12 in. by 6 in. terminal trench.
Secure mat to ground surface using U-shaped wire
staples, geotextile pi
ns, or wooden stakes.
Seed and fill turf reinforcement
matting with soil, if specified.
Soil Filling (if specified for turf reinforcement mat (TRM)) Installation should be in accordance with
the manufacturer’s recommendations. Typical
installation guidelines are as follows:
After seeding, spread and lightly rake ½-3/4 inch
es of fine topsoil into the TRM apertures to
completely fill TRM thickness. Use backside of rake or other flat implement.
Alternatively, if allowed by pr
oduct specifications, spread to
psoil using lightweight loader,
backhoe, or other power equipment.
Avoid sharp turns with equipment.
Always consult the manufacturer's recommendations for installation.
Do not drive tracked or heavy equipment over mat.
Avoid any traffic over matting if l
oose or wet soil conditions exist.
Use shovels, rakes, or brooms for fine grading and touch up.
Smooth out soil filling just exposing top netting of mat.
Temporary Soil Stabilization Removal
Temporary soil stabilization re
moved from the site of the wo
rk must be disposed of if
necessary.
Costs
Installed costs can be relatively
high compared to other BMPs.
Approximate costs for installed
materials are shown below:
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Rolled Erosion Control Products
Installed Cost per
Acre (2000)
1 Estimated Cost
per Acre (2009)
2 Biodegradable
Jute Mesh $6,000-$7,000
$6,600-$7,700
Curled Wood Fiber
$8,000-$10,500
$8,800-$11,050
Straw $8,000-$10,500
$8,800-$11,050
Wood Fiber
$8,000-$10,500
$8,800-$11,050
Coconut Fiber
$13,000-$14,000
$14,300-$15,400
Coconut Fiber Mesh
$30,000-$33,000
$33,000-$36,300
Straw Coconut Fiber
$10,000-$12,000
$11,000-$13,200
Non-Biodegradable
Plastic Netting $2,000-$2,200
$2,200-$2,220
Plastic Mesh
$3,000-$3,500
$3,300-$3,850
Synthetic Fiber with Netting
$34,000-$40,000
$37,400-$44,000
Bonded Synthetic Fibers
$45,000-$55,000
$49,500-$60,500
Combination with Biodegradable $30,000-$36,000
$33,000-$39,600
1. Source: Erosion Control Pilot Study Report, Caltrans, June 2000.
2. 2009 costs reflect a 10% escalation over year 2000 costs. Es calation based on informal survey of industry trends. Note:
Expected cost increase is offset
by competitive economic conditions.
Inspection and Maintenance
RECPs must be inspected in accordance with General Permit re quirements for the
associated project type and risk level. It
is recommended that at a minimum, BMPs be
inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Areas where erosion is evident shall be repaired
and BMPs reapplied as soon as possible.
Care should be exercised to mi
nimize the damage to protected areas while making repairs, as any area damaged will require reapplication of BMPs.
If washout or breakage occurs,
re-install the material after re
pairing the damage to the slope
or channel.
Make sure matting is uniformly in contact with the soil.
Check that all the lap joints are secure.
Check that staples are flush with the ground.
References
Erosion and Sediment Control Manual, Oregon De
partment of Environmental Quality, February
2005
Erosion Control Pilot Study Report, State of
California Department
of Transportation
(Caltrans), June 2000.
Guides for Erosion and Sediment Controls in
California, USDA Soils Conservation Service,
January 1991.
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National Management Measures to Control No
npoint Source Pollution from Urban Areas,
United States Environmental Protection Agency, 2002.
Stormwater Quality Handbooks Co
nstruction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.
Guidance Document: Soil Stabilization for Temporary Slopes, State of California Department of Transportation (Caltrans), November 1999.
Stormwater Management of the Puget Sound Ba
sin, Technical Manual, Publication #91-75,
Washington State Department
of Ecology, February 1992.
Water Quality Management Plan for The Lake
Tahoe Region, Volume II, Handbook of
Management Practices, Tahoe Regional
Planning Agency, November 1988.
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ATTACHMENT 7
Stabilized Construction Entrance/Exit
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Description and Purpose
A stabilized construction access is defined by a point of entrance/exit to a construction site that is stabilized to reduce the tracking of mud and dirt onto public roads by construction vehicles.
Suitable Applications
Use at construction sites:
Where dirt or mud can be tracked onto public roads.
Adjacent to water bodies.
Where poor soils are encountered.
Where dust is a problem during dry weather conditions.
Limitations
Entrances and exits require periodic top dressing with
additional stones.
This BMP should be used in conjunction with street
sweeping on adjacent public right of way.
Entrances and exits should be constructed on level ground only.
Stabilized construction entrances are rather expensive to construct and when a wash rack is included, a sediment trap of some kind must also be provided to collect wash water runoff.
Categories
EC
Erosion Control
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non
-
Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
Primary Objective
Secondary Objective
Targ
eted Constituents
Sediment
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
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Implementation
General
A stabilized construction entrance is a pad of aggregate underlain with filter cloth located at any point where traffic will be entering or leaving a construction site to or from a public right of way, street, alley, sidewalk, or parking area. The purpose of a stabilized construction entrance is to reduce or eliminate the tracking of sediment onto public rights of way or streets. Reducing tracking of sediments and other pollutants onto paved roads helps prevent deposition of sediments into local storm drains and production of airborne dust.
Where traffic will be entering or leaving the construction site, a stabilized construction entrance should be used. NPDES permits require that appropriate measures be implemented to prevent tracking of sediments onto paved roadways, where a significant source of sediments is
derived
from mud and dirt carried out from unpaved roads and construction sites.
Stabilized construction entrances are moderately effective in removing sediment from equipment leaving a construction site. The entrance should be built on level ground.
Advantages of the Stabilized Construction Entrance/Exit is that it does remove some sediment from equipment and serves to channel construction traffic in and out of the site at specified locations. Efficiency is greatly increased when a washing rack is included as part of a stabilized construction entrance/exit.
Design and Layout
Construct on level ground where possible.
Select 3 to 6 in. diameter stones.
Use minimum depth of stones of 12 in. or as recommended by soils engineer.
Construct length of 50 ft or maximum site will allow, and 10 ft minimum width or to
accommodate traffic.
Rumble racks constructed of steel panels with ridges and installed in the stabilized entrance/exit will help remove additional sediment and to keep adjacent streets clean.
Provide ample turning radii as part of the entrance.
Limit the points of entrance/exit to the construction site.
Limit speed of vehicles to control dust.
Properly grade each construction entrance/exit to prevent runoff from leaving the construction site.
Route runoff from stabilized entrances/exits through a sediment trapping device before discharge.
Design stabilized entrance/exit to support heaviest vehicles and equipment that will use it.
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Select construction access stabilization (aggregate, asphaltic concrete, concrete) based on longevity, required performance, and site conditions. Do not use asphalt concrete (AC) grindings for stabilized construction access/roadway.
If aggregate is selected, place crushed aggregate over geotextile fabric to at least 12 in. depth, or place aggregate to a depth recommended by a geotechnical engineer. A crushed aggregate greater than 3 in. but smaller than 6 in. should be used.
Designate combination or single purpose entrances and exits to the construction site.
Require that all employees, subcontractors, and suppliers utilize the stabilized construction access.
Implement SE-7, Street Sweeping and Vacuuming, as needed.
All exit locations intended to be used for more than a two-week period should have stabilized construction entrance/exit BMPs.
Inspection and Maintenance
Inspect and verify that activity
–
based BMPs are in place prior to the commencement of
associated activities. While activities associated with the BMPs are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Inspect local roads adjacent to the site daily. Sweep or vacuum to remove visible accumulated sediment.
Remove aggregate, separate and dispose of sediment if construction entrance/exit is clogged with sediment.
Keep all temporary roadway ditches clear.
Check for damage and repair as needed.
Replace gravel material when surface voids are visible.
Remove all sediment deposited on paved roadways within 24 hours.
Remove gravel and filter fabric at completion of construction Costs
Average annual cost for installation and maintenance may vary from $1,200 to $4,800 each, averaging $2,400 per entrance. Costs will increase with addition of washing rack, and sediment trap. With wash rack, costs range from $1,200 - $6,000 each, averaging $3,600 per entrance.
References
Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.
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National Management Measures to Control Nonpoint Source Pollution from Urban Areas, USEPA Agency, 2002.
Proposed Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters, Work Group Working Paper, USEPA, April 1992.
Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.
Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.
Virginia Erosion and Sedimentation Control Handbook, Virginia Department of Conservation and Recreation, Division of Soil and Water Conservation, 1991.
Guidance Specifying Management Measures for Nonpoint Pollution in Coastal Waters, EPA 840-B-9-
002
, USEPA, Office of Water, Washington, DC, 1993.
Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.
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ATTACHMENT 7
Fiber Rolls
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Description and Purpose
A fiber roll consists of straw,
coir, or other biodegradable
materials bound into a tight tu
bular roll wrapped by netting,
which can be photodegradable or
natural. Additionally, gravel
core fiber rolls are available, which contain an imbedded ballast material such as gravel or sand for additional weight when staking the rolls are not feasible (such as use as inlet protection). When fiber rolls are placed at the toe and on the face of slopes along the contours
, they intercept runoff, reduce
its flow velocity, release the ru
noff as sheet flow, and provide
removal of sediment from the runoff (through sedimentation).
By interrupting the length of a sl
ope, fiber rolls can also reduce
sheet and rill erosion until vegetation is established.
Suitable Applications
Fiber rolls may be suitable:
Along the toe, top, face, and at grade breaks of exposed and erodible slopes to shorten slop
e length and spread runoff as
sheet flow.
At the end of a downward slope where it transitions to a steeper slope.
Along the perimeter of a project.
As check dams in unlined di
tches with minimal grade.
Down-slope of exposed soil areas.
At operational storm drains as a form of inlet protection.
Categories
EC
Erosion Control
:
SE
Sediment Control
;
TC
Tracking Control
WE
Wind Erosion Control
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
SE-1 Silt Fence
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
SE-14 Biofilter Bags
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Around temporary stockpiles.
Limitations
Fiber rolls are not effective unless trenched in and staked.
Not intended for use in high flow situations.
Difficult to move once saturated.
If not properly staked and trenched in, fibe
r rolls could be transp
orted by high flows.
Fiber rolls have a very limited sediment capture zone.
Fiber rolls should not be used on slopes subject to creep, slumping, or landslide.
Rolls typically function for 12-24 months depending upon local conditions.
Implementation
Fiber Roll Materials
Fiber rolls should be prefabricated.
Fiber rolls may come manufactured containing
polyacrylamide (PAM), a flocculating agent
within the roll. Fiber rolls impregnated with
PAM provide additional sediment removal
capabilities and should be used in areas with fine, clayey or silty soils to provide additional sediment removal capabilities
. Monitoring may be requir
ed for these installations.
Fiber rolls are made from weed free rice straw,
flax, or a similar agricultural material bound
into a tight tubular roll by netting.
Typical fiber rolls vary in diameter from 9 in. to
20 in. Larger diameter rolls are available as
well.
Installation
Locate fiber rolls on level contours spaced as follows:
-
Slope inclination of 4:1 (H:V) or flatter:
Fiber rolls should be placed at a maximum
interval of 20 ft.
-
Slope inclination between 4:1 and 2:1 (H:V):
Fiber Rolls should be placed at a maximum
interval of 15 ft. (a closer
spacing is more effective).
-
Slope inclination 2:1 (H:V) or greater: Fi
ber Rolls should be placed at a maximum
interval of 10 ft. (a closer
spacing is more effective).
Prepare the slope before beginning installation.
Dig small trenches across the slop
e on the contour. The trench depth should be ¼ to 1/3 of the thickness of the roll, and the width should equal the roll diameter, in order to provide area to backfill the trench.
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It is critical that rolls are
installed perpendicular to water
movement, and parallel to the
slope contour.
Start building trenches and installing rolls from the bottom of the slope and work up.
It is recommended that pilot holes be driven
through the fiber roll. Use a straight bar to
drive holes through the roll and into the soil for the wooden stakes.
Turn the ends of the fiber roll up slope to prevent runoff from going around the roll.
Stake fiber rolls into the trench.
-
Drive stakes at the end of each fiber roll and spaced 4 ft maximum on center. -
Use wood stakes with a nominal classification of 0.75 by 0. 75 in. and minimum length of
24 in.
If more than one fiber roll is
placed in a row, the rolls should be overlapped, not abutted.
See typical fiber roll installation deta
ils at the end of
this fact sheet.
Removal
Fiber rolls can be left in plac
e or removed depending on the ty
pe of fiber roll and application
(temporary vs. permanent installa
tion). Typically, fiber rolls encased with plastic netting are used for a temporary application because the netti
ng does not biodegrade. Fiber rolls used in
a permanent application are typically encased with
a biodegradeable material and are left in
place. Removal of a fiber roll used in a
permanent application ca
n result in greater
disturbance.
Temporary installations should
only be removed when up gradient areas are stabilized per General Permit requirements, and/or pollutant so
urces no longer present a hazard. But, they
should also be removed before vegetation be
comes too mature so that the removal process
does not disturb more soil and vegetation than is necessary.
Costs
Material costs for regular fiber rolls
range from $20 - $30 per 25 ft roll.
Material costs for PAM impregnate
d fiber rolls range between 7.00
-$9.00 per linear foot, based
upon vendor research.
Inspection and Maintenance
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Repair or replace split, torn, un
raveling, or slumping fiber rolls.
If the fiber roll is used as a sediment captur
e device, or as an erosion control device to
maintain sheet flows, sediment that accumulate
s in the BMP should be periodically removed
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in order to maintain BMP effe
ctiveness. Sediment should be removed when sediment
accumulation reaches one-third the de
signated sediment storage depth.
If fiber rolls are used for eros
ion control, such as in a check dam, sediment removal should not be required as long as the system continues to control the grade. Sediment control BMPs will likely be required in conjun
ction with this type of application.
Repair any rills or
gullies promptly.
References
Stormwater Quality Handbooks - Construction Si
te Best Management Pr
actices (BMPs) Manual,
State of California Department of Transportation (Caltrans), March 2003.
Erosion and Sediment Control Manual, Oregon De
partment of Environmental Quality, February
2005.
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ATTACHMENT 7
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Description and Purpose
A silt fence is made of a woven geotextile that has been entrenched, attached to supporting poles, and sometimes backed by a plastic or wire mesh for support. The silt fence detains sediment-laden water, promoting sedimentation
behind the fence.
Suitable Applications
Silt fences are suitable for pe
rimeter control, placed below
areas where sheet flows discharge from the site. They could also be used as interior cont
rols below disturbed areas where
runoff may occur in the form of
sheet and rill erosion and
around inlets within disturbed ar
eas (SE-10). Silt fences are
generally ineffective in locations
where the flow is concentrated
and are only applicable for sheet or overland flows. Silt fences are most effective when used in combination with erosion controls. Suitable a
pplications include:
Along the perimeter of a project.
Below the toe or down slope of exposed and erodible slopes.
Along streams and channels.
Around temporary spoil areas and stockpiles.
Around inlets.
Below other small cleared areas.
Categories
EC
Erosion Control
SE
Sediment Control
;
TC
Tracking Control
WE
Wind Erosion Control
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
SE-5 Fiber Rolls
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
SE-10 Storm Drain Inlet Protection
SE-14 Biofilter Bags
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Limitations
Do not use in streams, channels, drain inlets, or anywhere flow is concentrated.
Do not use in locations where ponded water ma
y cause a flooding hazard. Runoff typically
ponds temporarily on the upstre
am side of silt fence.
Do not use silt fence to divert water flows
or place across any contour line. Fences not
constructed on a level contour, or fences used to divert flow will concentrate flows resulting in additional erosion and possibly overto
pping or failure of the silt fence.
Improperly installed fences are subject to failure from undercutting, overtopping, or collapsing.
Not effective unless trenched and keyed in.
Not intended for use as mid-slope protection on slopes greater than 4:1 (H:V).
Do not use on slopes subject to creeping, slumping, or landslides.
Implementation
General
A silt fence is a temporary sediment barrier cons
isting of woven geotexti
le stretched across and
attached to supporting posts, trenched-in, and,
depending upon the strength of fabric used,
supported with plastic or wire mesh fence. Si
lt fences trap sediment by intercepting and
detaining small amounts of sediment-laden runo
ff from disturbed areas in order to promote
sedimentation behind the fence.
The following layout and installation guidan
ce can improve performance and should be
followed:
Use principally in areas where sheet flow occurs.
Install along a level contour, so water does not pond more than 1.5 ft at any point along the silt fence.
The maximum length of slope draining to any point along the silt fence should be 200 ft or less.
The maximum slope perpendicular to the fence line should be 1:1.
Provide sufficient room for runoff to pond behi
nd the fence and to allow sediment removal
equipment to pass between the silt fence and to
es of slopes or other obstructions. About
1200 ft
2 of ponding area should be provided
for every acre draining to the fence.
Turn the ends of the filter fence uphill to prevent stormwater from flowing around the fence.
Leave an undisturbed or stabilized area immediately down slope from the fence where feasible.
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Silt fences should remain in place until the disturbed area is permanently stabilized, after which, the silt fence should be removed and properly disposed.
Silt fence should be used in
combination with erosion source controls up slope in order to provide the most effective sediment control.
Be aware of local regulations regarding the type
and installation requirements of silt fence,
which may differ from those presented in this fact sheet.
Design and Layout
The fence should be supported by a plastic or wi
re mesh if the fabric selected does not have
sufficient strength and bursting strength ch
aracteristics for the planned application (as
recommended by the fabric manufacturer). Woven geotextile material should contain ultraviolet inhibitors and stabilizers to provide a minimum of
six months of expected usable construction
life at a temperature range of 0 °F to 120 °F.
Layout in accordance with attached figures.
For slopes steeper than 2:1 (H:V) and that contain a high number of rocks or large dirt clods that tend to dislodge, it may be necessary
to install additional protection immediately
adjacent to the bottom of the slope, prior to in
stalling silt fence. Additional protection may
be a chain link fence or a cable fence.
For slopes adjacent to sensitiv
e receiving waters or Environm
entally Sensitive Areas (ESAs),
silt fence should be used in conj
unction with erosion control BMPs.
Standard vs. Heavy Duty Silt Fence
Standard Silt Fence
Generally applicable in cases where the slope of area draining to the silt fence is 4:1 (H:V) or less.
Used for shorter durations, typically 5 months or less
Area draining to fence produces moderate sediment loads.
Heavy Duty Silt Fence
Use is generally limited to 8 months or less.
Area draining to fence produces moderate sediment loads.
Heavy duty silt fence usually has 1 or mo
re of the following characteristics, not
possessed by standard silt fence.
o
Fence fabric has higher tensile strength.
o
Fabric is reinforced with wire
backing or additional support.
o
Posts are spaced closer than pre-manufactured, standard silt fence products. o
Posts are metal (steel or aluminum)
Materials
Standard Silt Fence
Silt fence material should be woven geotex
tile with a minimum width of 36 in. and a
minimum tensile strength of 100 lb force. The
fabric should conform to the requirements in
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reinforcement layer should be a polypropylene, or equivalent, net provided by the manufacturer. The permittivity of the fabric should be between 0.1 sec -1
and 0.15 sec
-1
in
conformance with the requirements in ASTM designation D4491.
Wood stakes should be commercial quality lumber
of the size and shape shown on the plans.
Each stake should be free from decay, splits or
cracks longer than the thickness of the stake
or other defects that would weaken the stakes
and cause the stakes to be structurally
unsuitable.
Staples used to fasten the fence fabric to the st
akes should be not less than 1.75 in. long and
should be fabricated from 15 gauge or heavier wire. The wire used to fasten the tops of the stakes together when joining two sections of fence should be 9 gauge or heavier wire.
Galvanizing of the fastening wire will not be required.
Heavy-Duty Silt Fence
Some silt fence has a wire backing to provide additional support, and there are products that may use prefabricated plastic holders for the silt fence and use metal posts or bar reinforcement instead of wood stakes. If bar re
inforcement is used in lieu of wood stakes,
use number four or greater bar. Provide en
d protection for any ex
posed bar reinforcement
for health and safety purposes.
Installation Guidelines – Traditional Method
Silt fences are to be constructed on a level contour. Sufficient area should exist behind the fence for ponding to occur without flood
ing or overtopping the fence.
A trench should be excavated approximately 6 in. wide and 6 in. deep along the line of the proposed silt fence (trenches should not be
excavated wider or deep
er than necessary for
proper silt fence installation).
Bottom of the silt fence should be keyed-in a minimum of 12 in.
Posts should be spaced a maximum of 6 ft ap
art and driven securely into the ground a
minimum of 18 in. or 12 in.
below the bottom of the trench.
When standard strength geotextile is used, a
plastic or wire mesh support fence should be
fastened securely to the upslop
e side of posts using heavy–duty wire staples at least 1 in. long. The mesh should extend into the trench.
When extra-strength geotextile and closer post spacing are used, the mesh support fence may be eliminated.
Woven geotextile should
be purchased in a long roll, then cu
t to the length of the barrier.
When joints are necessary, geotex
tile should be spliced together
only at a support post, with
a minimum 6 in. overlap and both ends securely fastened to the post.
The trench should be backfilled with
native material and compacted.
Construct silt fences with a setback of at least
3 ft from the toe of a slope. Where, due to
specific site conditions, a 3 ft setback is not av
ailable, the silt fence may be constructed at the
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toe of the slope, but should be constructed as far from the toe of the slope as practicable. Silt fences close to the toe of the slope will be less effective and more difficult to maintain.
Construct the length of each reach so that the
change in base elevation along the reach does
not exceed 1/3 the height of the barrier; in
no case should the reach exceed 500 ft.
Cross barriers should be a minimum of
1 /
3 and a maximum of ½ the height of the linear
barrier.
See typical installation details at
the end of this fact sheet.
Installation Guidelines - Static Slicing Method
Static Slicing is defined as in
sertion of a narrow blade pulled behind a tractor, similar to a plow blade, at least 10 inches into the soil while at the same time pulling silt geotextile fabric into the ground through the opening created by the blade to the depth of the blade. Once the gerotextile is inst
alled, the soil is compacted using tractor tires.
This method will not work with pre-fa
bricated, wire backed silt fence.
Benefits:
o
Ease of installation (most often done
with a 2 person crew). In addition,
installation using static slic
ing has been found to be more efficient on slopes, in
rocky soils, and in saturated soils.
o
Minimal soil disturbance.
o
Greater level of compaction along fence,
leading to higher performance (i.e.
greater sediment retention).
o
Uniform installation.
o
Less susceptible to undercutting/undermining.
Costs
It should be noted that costs vary greatly ac
ross regions due to avai
lable supplies and labor
costs.
Average annual cost for installation using th
e traditional silt fence installation method
(assumes 6 month useful life) is $7 per linear
foot based on vendor research. Range of cost
is $3.50 - $9.10 per linear foot.
In tests, the slicing method required 0.33 man hours per 100 linear feet, while the trenched based systems required as much as 1.01 man hours per linear foot.
Inspection and Maintenance
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Repair undercut silt fences.
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Repair or replace split, torn, slumping, or weathe
red fabric. The lifespan of silt fence fabric
is generally 5 to 8 months.
Silt fences that are damaged and become unsuitable for the intended purpose should be removed from the site of work, disposed, an
d replaced with new silt fence barriers.
Sediment that accumulates in the BMP should be
periodically removed
in order to maintain
BMP effectiveness. Sediment should be remo
ved when the sediment accumulation reaches
one-third of the barrier height.
Silt fences should be left in place until the upstream area is permanently stabilized. Until then, the silt fence should be inspected and maintained regularly.
Remove silt fence when upgradient areas are
stabilized. Fill and compact post holes and
anchor trench, remove sediment accumulation,
grade fence alignment to blend with adjacent
ground, and stabilize disturbed area.
References
Manual of Standards of Erosion and Sediment
Control Measures, Association of Bay Area
Governments, May 1995.
National Management Measures to Control No
npoint Source Pollution from Urban Areas,
United States Environmental Protection Agency, 2002.
Proposed Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters, Work Group-Work
ing Paper, USEPA, April 1992.
Sedimentation and Erosion Control Practices,
and Inventory of Current
Practices (Draft),
UESPA, 1990.
Southeastern Wisconsin Regional Planning Comm
ission (SWRPC). Costs of Urban Nonpoint
Source Water Pollution Control Measures. Technical Report No. 31. Southeastern Wisconsin Regional Planning Commission, Waukesha, WI. 1991
Stormwater Quality Handbooks - Construction Si
te Best Management Pr
actices (BMPs) Manual,
State of California Department of Transportation (Caltrans), March 2003.
Stormwater Management Manual for The Puget So
und Basin, Washington State Department of
Ecology, Public Review Draft, 1991.
U.S. Environmental Protection Agency (USEPA
). Stormwater Management for Industrial
Activities: Developing Pollution Prevention
Plans and Best Management Practices. U.S.
Environmental Protection Agency, Offi
ce of Water, Washington, DC, 1992.
Water Quality Management Plan for the Lake
Tahoe Region, Volume II, Handbook of
Management Practices, Tahoe Regional Planni
ng Agency, November 19
88.Soil Stabilization
BMP Research for Erosion and Se
diment Controls: Cost Survey Technical Memorandum, State of California Department of Tran
sportation (Caltrans), July 2007.
Erosion and Sediment Control Manual, Oregon De
partment of Environmental Quality, February
2005.
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ATTACHMENT 7
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Description and Purpose
Storm drain inlet protection consis
ts of a sediment filter or an
impounding area in, around or upstream of a storm drain, drop inlet, or curb inlet. Storm
drain inlet protection measures
temporarily pond runoff before it enters the storm drain, allowing sediment to settle. So
me filter configurations also
remove sediment by filtering, but usually the ponding action results in the greatest sedi
ment reduction. Temporary
geotextile storm drain inserts
attach underneath storm drain
grates to capture and filter storm water.
Suitable Applications
Every storm drain inlet receivin
g runoff from unstabilized or
otherwise active work areas sh
ould be protected. Inlet
protection should be used in
conjunction with other erosion
and sediment controls to prevent sediment-laden stormwater and non-stormwater discharges from entering the storm drain system.
Limitations
Drainage area should not exceed 1 acre.
In general straw bales shou
ld not be used as inlet
protection.
Requires an adequate area for water to pond without
encroaching into portions of the roadway subject to traffic.
Categories
EC
Erosion Control
SE
Sediment Control
;
TC
Tracking Control
WE
Wind Erosion Control
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
:
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
SE-1 Silt Fence
SE-5 Fiber Rolls
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
SE-14 Biofilter Bags
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Sediment removal may be inadequate to prevent sediment discharges in high flow conditions or if runoff is heavil
y sediment laden. If high fl
ow conditions are expected, use
other onsite sediment trapping techniques
in conjunction with inlet protection.
Frequent maintenance is required.
Limit drainage area to 1 acre maximum. For dr
ainage areas larger than 1 acre, runoff should
be routed to a sediment-trappi
ng device designed for larger flows. See BMPs SE-2,
Sediment Basin, and SE-3, Sediment Traps.
Excavated drop inlet sediment traps are a
ppropriate where relatively heavy flows are
expected, and overflow capability is needed.
Implementation
General
Inlet control measures presented in this handbook should not be used for inlets draining more than one acre. Runoff from larger disturbed
areas should be first
routed through SE-2,
Sediment Basin or SE-3, Sediment Trap and/or us
ed in conjunction with other drainage control,
erosion control, and sediment control BMPs to protect the site. Different types of inlet protection are appropriate for di
fferent applications de
pending on site conditions and the type
of inlet. Alternative methods are available in addition to the methods described/shown herein such as prefabricated inlet insert device
s, or gutter protection devices.
Design and Layout
Identify existing and planned storm drain inlets
that have the potential to receive sediment-
laden surface runoff. Determine if storm drain inlet protection is needed and which method to use.
The key to successful and safe use of storm dr
ain inlet protection devices is to know where
runoff that is directed toward the inlet to be protected will pond or be diverted as a result of installing the protection device.
-
Determine the acceptable location and extent of ponding in the vicinity of the drain inlet.
The acceptable location and extent of pondin
g will influence the type and design of the
storm drain inlet protection device.
-
Determine the extent of potential runoff di
version caused by the storm drain inlet
protection device. Runoff ponded by inlet pr
otection devices may flow around the device
and towards the next downstream inlet. In some
cases, this is accept
able; in other cases,
serious erosion or downstream property damage
can be caused by these diversions. The
possibility of runoff diversions will influenc
e whether or not storm drain inlet protection
is suitable; and, if suitable, th
e type and design of the device.
The location and extent of ponding, and the ex
tent of diversion, can usually be controlled
through appropriate placement of the inlet prot
ection device. In so
me cases, moving the
inlet protection device a short distance upst
ream of the actual inlet can provide more
efficient sediment control, limit ponding to de
sired areas, and prevent or control diversions.
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Six types of inlet protection are presented belo
w. However, it is recognized that other
effective methods and proprietary de
vices exist and may be selected.
-
Silt Fence: Appropriate for drainage basins
with less than a 5% slope, sheet flows, and
flows under 0.5 cfs.
-
Excavated Drop Inlet Sediment Trap: An
excavated area around the inlet to trap
sediment (SE-3).
-
Gravel bag barrier: Used to create a small se
diment trap upstream of inlets on sloped,
paved streets. Appropriate for sheet flow or when concentrated flow may exceed 0.5 cfs, and where overtopping is required to prevent flooding.
-
Block and Gravel Filter: Appropriat
e for flows greater than 0.5 cfs.
-
Temporary Geotextile Storm drain Inserts: Diffe
rent products provide different features.
Refer to manufacturer details for targeted pollutants and additional features. -
Biofilter Bag Barrier: Used to create a small
retention area upstream of inlets and can be
located on pavement or soil. Biofilter bags sl
owly filter runoff allowing sediment to settle
out. Appropriate for flows under 0.5 cfs.
Select the appropriate type of inlet protection
and design as referred to or as described in
this fact sheet.
Provide area around the inlet for water to po
nd without flooding stru
ctures and property.
Grates and spaces around all inlets should be
sealed to prevent seepage of sediment-laden
water.
Excavate sediment sumps (where needed) 1 to 2
ft with 2:1 side slopes around the inlet.
Installation
DI Protection Type 1 - Silt Fence -
Similar to constructing a silt fence; see BMP SE-1,
Silt Fence. Do not place fabric underneath
the inlet grate since the collected sediment may
fall into the drain inlet when the fabric is re
moved or replaced and
water flow through the
grate will be blocked resulting in flooding. See typical Type 1 installation details at the end of this fact sheet.
1. Excavate a trench approximately 6 in. wide and 6 in. deep along the line of the silt fence inlet protection device.
2. Place 2 in. by 2 in. wooden stakes around the perimeter of the inlet a maximum of 3 ft apart and drive them at least 18 in. into th
e ground or 12 in. below the bottom of the
trench. The stakes should be at least 48 in.
3. Lay fabric along bottom of trench, up side of
trench, and then up st
akes. See SE-1, Silt
Fence, for details. The maximum silt fe
nce height around the inlet is 24 in.
4. Staple the filter fabric (for materials and specifications, see SE-1, Silt Fence) to wooden stakes. Use heavy-duty wire st
aples at least 1 in. in length.
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5. Backfill the trench with gravel or compacted earth all the way around.
DI Protection Type 2 - Excavated Drop Inlet Sediment Trap - Install filter fabric
fence in accordance with DI Protection Type 1. Size excavated trap to provide a minimum storage capacity calculated at the rate 67 yd
3 /acre of drainage area. See typical Type 2
installation details at the end of this fact sheet.
DI Protection Type 3 - Gravel bag -
Flow from a severe stor
m should not overtop the
curb. In areas of high clay and silts, use filter
fabric and gravel as additional filter media.
Construct gravel bags in accordance with SE-6
, Gravel Bag Berm. Gravel bags should be
used due to their high permeability. See typical Type 3 installation details at the end of this fact sheet.
1. Construct on gently sloping street.
2. Leave room upstream of barrier for wa
ter to pond and sediment to settle.
3. Place several layers of gravel bags – over
lapping the bags and packing them tightly
together.
4. Leave gap of one bag on the top row to serve
as a spillway. Flow from a severe storm
(e.g., 10 year storm) should not overtop the curb.
DI Protection Type 4 – Block and Gravel Filter -
Block and gravel filters are suitable
for curb inlets commonly used
in residential, commercial, an
d industrial construction. See
typical Type 4 installation details
at the end of this fact sheet.
1. Place hardware cloth or compar
able wire mesh with 0.5 in.
openings over the drop inlet
so that the wire extends a minimum of 1 ft beyond each side of the inlet structure. If more than one strip is necessary, overlap the strips. Place woven geotextile over the wire mesh.
2. Place concrete blocks lengthwise on their si
des in a single row around the perimeter of
the inlet, so that the open ends face outwar
d, not upward. The ends of adjacent blocks
should abut. The height of the barrier can
be varied, depending on design needs, by
stacking combinations of blocks that are 4 in.,
8 in., and 12 in. wide. The row of blocks
should be at least 12 in. but no greater than 24 in. high.
3. Place wire mesh over the outside vertical face (open end) of the concrete blocks to prevent stone from being washed through the blocks. Use hardware cloth or comparable wire mesh with 0.5 in. opening.
4. Pile washed stone against the wire mesh to
the top of the blocks. Use 0.75 to 3 in.
DI Protection Type 5 – Temporary Geotextile Insert (proprietary) – Many types
of temporary inserts are available. Most insert
s fit underneath the grate of a drop inlet or
inside of a curb inlet and are fastened to the outside of the grate or curb. These inserts are removable and many can be cleaned and reused
. Installation of
these inserts differs
between manufacturers. Please refer to ma
nufacturer instruction
for installation of
proprietary devices.
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DI Protection Type 6 -
Biofilter bags
– Biofilter bags may be used as a substitute for
gravel bags in low-flow situations. Biofilter
bags should conform to specifications detailed
in SE-14, Biofilter bags.
1. Construct in a gently sloping area.
2. Biofilter bags should be placed arou
nd inlets to intercept runoff flows.
3. All bag joints should overlap by 6 in.
4. Leave room upstream for water to pond
and for sediment to settle out.
5. Stake bags to the ground as described in the following detail. Stakes may be omitted if bags are placed on a paved surface.
Costs
Average annual cost for installation and mainte
nance of DI Type 1-4 and 6 (one year useful
life) is $200 per inlet.
Temporary geotextile inserts are proprietary and cost varies by region. These inserts can often be reused and may have greater than 1 year of use if maintained and kept undamaged.
Average cost per insert ranges from $50-75 plus installation, but costs can exceed $100.
This cost does not include maintenance.
Inspection and Maintenance
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Silt Fences. If the fabric becomes clogged, torn, or degrades, it should be replaced. Make sure the stakes are securely driven in the gr
ound and are in good shape (i.e., not bent,
cracked, or splintered, and are reasonably pe
rpendicular to the ground). Replace damaged
stakes. At a minimum, remove the sediment behind the fabric fence when accumulation reaches one-third the height of the fence or barrier height.
Gravel Filters. If the gravel becomes clogged
with sediment, it should
be carefully removed
from the inlet and either cleaned or replaced. Since cleaning gravel at a construction site may be difficult, consider using
the sediment-laden stone as fill material and put fresh stone around the inlet. Inspect bags for holes, gashes, and snags, and replace bags as needed.
Check gravel bags for proper arrangement and displacement.
Sediment that accumulates in the BMP should be
periodically removed
in order to maintain
BMP effectiveness. Sediment should be remo
ved when the sediment accumulation reaches
one-third of the barrier height.
Inspect and maintain temporary geotextile in
sert devices according to manufacturer’s
specifications.
Remove storm drain inlet protection on
ce the drainage ar
ea is stabilized.
ATTACHMENT 7
Storm Drain Inlet Protection SE-10
November 2009
California Stormwater BMP Handbook
6 of 10
Construction
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-
Clean and regrade area around the inlet and clean the inside of the storm drain inlet, as it should be free of sediment and debr
is at the time of final inspection.
References
Stormwater Quality Handbooks - Construction Si
te Best Management Pr
actices (BMPs) Manual,
State of California Department of Transportation (Caltrans), March 2003.
Stormwater Management Manual for The Puget So
und Basin, Washington State Department of
Ecology, Public Review Draft, 1991.
Erosion and Sediment Control Manual, Oregon De
partment of Environmental Quality, February
2005.
ATTACHMENT 7
Storm Drain Inlet Protection SE-10
November 2009
California Stormwater BMP Handbook
7 of 10
Construction
www.casqa.org
ATTACHMENT 7
Storm Drain Inlet Protection SE-10
November 2009
California Stormwater BMP Handbook
8 of 10
Construction
www.casqa.org
ATTACHMENT 7
Storm Drain Inlet Protection SE-10
November 2009
California Stormwater BMP Handbook
9 of 10
Construction
www.casqa.org
ATTACHMENT 7
Storm Drain Inlet Protection SE-10
November 2009
California Stormwater BMP Handbook
10 of 10
Construction
www.casqa.org
ATTACHMENT 7
Concrete Waste Management WM-8
November 2009
California Stormwater BMP Handbook
1 of 7
Construction
www.casqa.org
Description and Purpose
Prevent the discharge of pollutants to stormwater from
concrete waste by conducting wa
shout onsite or offsite in a
designated area, and by employ
ee and subcontractor training.
The General Permit incorporat
es Numeric Effluent Limits
(NEL) and Numeric Action Levels
(NAL) for pH (see Section 2
of this handbook to determine yo
ur project’s risk level and if
you are subject to these requirements).
Many types of construction materials, including mortar, concrete, stucco, cement and bloc
k and their associated wastes
have basic chemical properties that can raise pH levels outside of the permitted range. Additional care should be taken when managing these materials to prevent them from coming into contact with stormwater flows and raising pH to levels outside the accepted range.
Suitable Applications
Concrete waste management procedures and practices are
implemented on construction projects where:
Concrete is used as a construction material or where
concrete dust and debris result from demolition activities.
Slurries containing portland cement concrete (PCC) are generated, such as from saw cutting, coring, grinding,
grooving, and hydro-concrete demolition.
Categories
EC
Erosion Control
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non-Stormwater
Management Control
:
WM
Waste Management and
Materials Pollution Control
;
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
;
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
ATTACHMENT 7
Concrete Waste Management WM-8
November 2009
California Stormwater BMP Handbook
2 of 7
Construction
www.casqa.org
Concrete trucks and other concrete-coated equipment are washed onsite.
Mortar-mixing stations exist.
Stucco mixing and spraying .
See also NS-8, Vehicle and Equipment Cleaning.
Limitations
Offsite washout of concrete wast
es may not always be possible.
Multiple washouts may be needed to assure ad
equate capacity and to allow for evaporation.
Implementation
The following steps will help
reduce stormwater pollution from concrete wastes:
Incorporate requirements for concrete wast
e management into material supplier and
subcontractor agreements.
Store dry and wet materials under cover, away fr
om drainage areas. Refer to WM-1, Material
Delivery and Storage for more information.
Avoid mixing excess amounts of concrete.
Perform washout of concrete tr
ucks in designated areas only, where washout will not reach stormwater.
Do not wash out concrete trucks into storm drai
ns, open ditches, street
s, streams or onto the
ground. Trucks should always be wash
ed out into designated facilities.
Do not allow excess concrete to be dumped
onsite, except in designated areas.
For onsite washout:
-
On larger sites, it is recommended to locate washout areas at least 50 feet from storm drains, open ditches, or water bodies. Do no
t allow runoff from this area by constructing
a temporary pit or bermed area large
enough for liquid and solid waste.
-
Washout wastes into the temporary washout wh
ere the concrete can set, be broken up,
and then disposed properly.
-
Washout should be lined so there is no
discharge into the underlying soil.
Do not wash sweepings from exposed aggregate
concrete into the street or storm drain.
Collect and return sweepings to aggregate
base stockpile or dispose in the trash.
See typical concrete washout installation de
tails at the end of this fact sheet.
Education
Educate employees, subcontractors, and suppl
iers on the concrete waste management
techniques described herein.
ATTACHMENT 7
Concrete Waste Management WM-8
November 2009
California Stormwater BMP Handbook
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Construction
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Arrange for contractor’s superi
ntendent or representative to oversee and enforce concrete waste management procedures.
Discuss the concrete management
techniques described in this BMP (such as handling of
concrete waste and washout) with the ready-mi
x concrete supplier before any deliveries are
made.
Concrete Demolition Wastes
Stockpile concrete demolition waste in acco
rdance with BMP WM-3,
Stockpile Management.
Dispose of or recycle hardened concrete waste in accordance with applicable federal, state or local regulations.
Concrete Slurry Wastes
PCC and AC waste should no
t be allowed to enter storm drains or watercourses.
PCC and AC waste should be collected and disposed of or pl aced in a temporary concrete
washout facility (as described in Onsite Te
mporary Concrete Washout Facility, Concrete
Transit Truck Washout Procedures, below).
A foreman or construction supervisor should mo
nitor onsite concrete working tasks, such as
saw cutting, coring, grinding and grooving to
ensure proper meth
ods are implemented.
Saw-cut concrete slurry should not be allowe
d to enter storm drains or watercourses.
Residue from grinding operations should be pi
cked up by means of a vacuum attachment to
the grinding machine or by sweeping. Saw cu
tting residue should not be allowed to flow
across the pavement and should not be left on
the surface of the pavement. See also NS-3,
Paving and Grinding Operations; and WM-10, Liquid Waste Management.
Concrete slurry residue should
be disposed in a temporary washout facility (as described in Onsite Temporary Concrete Washout Facility,
Concrete Transit Truck Washout Procedures,
below) and allowed to dry. Dispose of dry sl
urry residue in accord
ance with WM-5, Solid
Waste Management.
Onsite Temporary Concrete Washout Facility, Transit Truck Washout Procedures
Temporary concrete washout faci
lities should be located a minimum of 50 ft from storm
drain inlets, open drainage facilities, and waterc
ourses. Each facility should be located away
from construction traffic or access areas to prevent disturbance or tracking.
A sign should be installed adjacent to each
washout facility to inform concrete equipment
operators to utilize the proper facilities.
Temporary concrete washout faci
lities should be constructed above grade or below grade at the option of the contractor. Temporary concrete washout facilities should be constructed and maintained in sufficient quantity and size to contain all liquid and concrete waste generated by washout operations.
ATTACHMENT 7
Concrete Waste Management WM-8
November 2009
California Stormwater BMP Handbook
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Construction
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Temporary washout facilities should have a
temporary pit or bermed
areas of sufficient
volume to completely contain all liquid an
d waste concrete materi
als generated during
washout procedures.
Temporary washout facilities shou
ld be lined to prevent discharge to the underlying ground or surrounding area.
Washout of concrete trucks should be
performed in designated areas only.
Only concrete from mixer truck chutes shou
ld be washed into concrete wash out.
Concrete washout from concrete pumper bins
can be washed into concrete pumper trucks
and discharged into designated washout area or
properly disposed of or recycled offsite.
Once concrete wastes are washed into the designated area and allowed to harden, the concrete should be broken up, removed,
and disposed of per WM-5, Solid Waste
Management. Dispose of or recycle hardened concrete on a regular basis.
Temporary Concrete Washout Facility (Type Above Grade)
-
Temporary concrete washout faci
lity (type above grade) should be constructed as shown
on the details at the end of this BMP,
with a recommended minimum length and
minimum width of 10 ft; however, smaller site
s or jobs may only need a smaller washout
facility. With any washout, always maintain
a sufficient quantity and volume to contain
all liquid and concrete waste generated by washout operations. -
Materials used to construct the washout area
should conform to the provisions detailed
in their respective BMPs (e.g., SE-8 Sandbag Barrier).
-
Plastic lining material should be a minimum of 10 mil in polyethylene sheeting and should be free of holes, tears, or other defe
cts that compromise the impermeability of the
material.
-
Alternatively, portable removable containers can be used as above grade concrete washouts. Also called a “roll-off”; this co
ncrete washout facility should be properly
sealed to prevent leakage, and should be re
moved from the site and replaced when the
container reaches 75% capacity.
Temporary Concrete Washout Fa
cility (Type Below Grade)
-
Temporary concrete washout facilities (typ
e below grade) should be constructed as
shown on the details at the end of this BM
P, with a recommended minimum length and
minimum width of 10 ft. The quantity and
volume should be sufficient to contain all
liquid and concrete waste gene
rated by washout operations.
-
Lath and flagging should be commercial type.
-
Plastic lining material should be a minimum
of 10 mil polyethylene sheeting and should
be free of holes, tears, or other defects
that compromise the im
permeability of the
material.
ATTACHMENT 7
Concrete Waste Management WM-8
November 2009
California Stormwater BMP Handbook
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Construction
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-
The base of a washout facility should be free of rock or debris that may damage a plastic liner.
Removal of Temporary Concrete Washout Facilities
When temporary concrete washout facilities
are no longer required for the work, the
hardened concrete should be removed and proper
ly disposed or recycled in accordance with
federal, state or local regulati
ons. Materials used to construct temporary concrete washout facilities should be removed from the site of
the work and properly disposed or recycled in
accordance with federal, state or local regulations..
Holes, depressions or other ground disturba
nce caused by the removal of the temporary
concrete washout facilities shou
ld be backfilled and repaired.
Costs
All of the above are low cost measures. Roll-0ff
concrete washout facilities can be more costly
than other measures due to removal and replacement; however, provide a cleaner alternative to traditional washouts. The type of washout faci
lity, size, and availabi
lity of materials will
determine the cost of the washout.
Inspection and Maintenance
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Temporary concrete washout faci
lities should be maintained to provide adequate holding capacity with a minimum freeboard of 4 in. fo
r above grade facilities and 12 in. for below
grade facilities. Maintaining temporary concrete
washout facilities sh
ould include removing
and disposing of hardened concrete and returnin
g the facilities to a functional condition.
Hardened concrete materials sh
ould be removed and properly
disposed or recycled in
accordance with federal, state or local regulations.
Washout facilities must be cleaned, or new facilities must be constructed and ready for use once the washout is 75% full.
Inspect washout facilities for damage (e.g. torn li
ner, evidence of leaks, signage, etc.). Repair
all identified damage.
References
Blueprint for a Clean Bay: Best Management Pr
actices to Prevent Stormwater Pollution from
Construction Related Activities; Santa Clara Vall
ey Nonpoint Source Pollution Control Program,
1995.
Stormwater Quality Handbooks - Construction Si
te Best Management Pr
actices (BMPs) Manual,
State of California Department of Transporta
tion (Caltrans), November 2000, Updated March
2003.
Stormwater Management for Construction Activi
ties; Developing Pollution Prevention Plans
and Best Management Practice, EPA
832-R-92005; USEPA, April 1992.
ATTACHMENT 7
Concrete Waste Management WM-8
November 2009
California Stormwater BMP Handbook
6 of 7
Construction
www.casqa.org
ATTACHMENT 7
Concrete Waste Management WM-8
November 2009
California Stormwater BMP Handbook
7 of 7
Construction
www.casqa.org
ATTACHMENT 7
Stockpile Management
WM
-3
January 2011
Construction
www.
casqa.org
Description and Purpose
Stockpile
management
procedures and practices are designed
to reduce or eliminate air and stormw
ater pollution from
stockpiles of soil,
soil amendments,
sand,
paving materials such
as portland cement concrete (PCC) rubble, asphalt concrete (AC), asphalt concrete rubble, aggregate base, aggregate sub base or pre
-
mixed aggregate, asphalt minder (so cal
led “cold
mix” asphalt), and pressure treated wood.
Suitable Applications
Implement in all projects that stockpile soil and
other loose
materials.
Limitations
Plastic sheeting as a stockpile
protection
is temporary and
hard to manage in windy conditions.
W
here plastic is used,
consider use of plastic tarps with nylon reinforcement
which may be more durable than standard sheeting.
Plastic sheeting can increase runoff volume due to lack of infiltration and potentially cause perimeter control failure.
Plastic
sheeting breaks down faster in
sunlight
.
The use of
p
lastic materials
should be avoided when feasible
and photodegradable plastics
should
not be used.
Implementation
Protection of stockpiles is a year
-
round requirement. To properly
manage stockpiles:
Categor
ies
EC
Erosion Control
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non
-
Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
Primary
Category
Secondary
Category
Target
ed Constituents
Sediment
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
ATTACHMENT 7
Stockpile Management
WM
-3
January 2011
Construction
www.
casqa.org
On larger sites, a minimum
of 50 ft
separation from
concentrated flows of stormwater,
drainage courses, and inlets
is recommended
.
All stockpiles are required to be protected
immediately if they are not scheduled to be used
within 14 days.
Protect all stockpiles from stormwater run
-
on using temporary perimeter sediment barrier
s
such as
compost
berms
(SE
-
13)
,
temporary silt
dikes
(SE
-
12)
, fiber rolls
(SE
-
5)
, silt fences
(SE
-
1)
, sandbag
s
(SE
-
8)
, gravel bags
(SE
-
6)
,
or
biofilter bags
(SE
-
14).
Refer to the ind
ividual
fact sheet for
each of
these controls for installation information.
Implement wind erosion control practices as appropriate on all stockpiled material. For specific information, see WE
-
1, Wind Erosion Control.
Manage stockpiles of contaminated soi
l in accordance with WM
-
7, Contaminated Soil
Management.
Place bagged materials on pallets and under cover.
Ensure that stockpile coverings are installed securely to protect from wind and rain.
Some plastic covers withstand weather and sunlight better tha n others
.
Select cover
materials or methods based on anticipated duration of use.
Protection of Non
-
Active Stockpiles
Non
-
active stockpiles of the identified materials should be protected further as follows:
Soil stockpiles
Cover and project s
oil
stockpil
es with soil stabilization measures and a temporary perimeter sediment barrier at all times.
Consider temporary vegetation for topsoil piles that will be stockpiled for extended periods.
Stockpiles of Portland cement concrete rubble, asphalt concrete, asph alt concrete rubble,
aggregate base, or aggregate sub base
Provide covers and protect these stockpiles with a temporary perimeter sediment barrier at all times.
Stockpiles of “cold mix”
Cover cold mix stockpiles and place them on
plastic
sheeting
(
or compa
rable material
)
and
surround the stockpiles with a berm all times.
Stockpiles of
fly
ash, stucco, hydrated lime
Cover s
tockpile
s
of materials that may raise the pH of runoff (i.e.,
basic materials)
with
plastic and surround
the stockpiles with a
berm
at al
l times
.
ATTACHMENT 7
Stockpile Management
WM
-3
January 2011
Construction
www.
casqa.org
Stockpiles/Storage of wood (Pressure treated
with c
hromated
c
opper
arsenate
or ammoni
a
cal
copper zinc arsenate
)
Cover t
reated wood with plastic
sheeting
(
or comparable material
)
and surround with a
berm
at all times.
Protection of Active Stockpile
s
Active stockpiles of the identified materials should be protected as follows:
All stockpiles should be
covered and
protected with a temporary linear sediment barrier
prior to the onset of precipitation.
Stockpiles of “cold mix”
and treated wood, and basic materials
should be placed on and
covered with plastic
sheeting
or comparable material
and surrounded by a berm
prior to the
onset of precipitation.
T
he downstream perimeter
of a
n active
stockpile should be protected with
a linear sediment
barrier
or ber
m
and
runoff should be diverted around or away from the
stockpile
on the
upstream perimeter.
Costs
For cost information associated with stockpile protection refer to the individual erosion or sediment control BMP fact sheet
considered for implementation
(F
or example, refer to SE
-
1 Silt
Fence for installation of silt fence around the
perimeter of a
stockpile.)
Inspection and Maintenance
Stockpiles
must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
It may be necessary to inspect stockpiles covered with plastic sheeting more freq uently
during certain conditions
(for example,
high
wind
s
or
extreme
h
eat).
Repair and/or replace perimeter controls and covers as needed to keep them functioning properly.
Sediment shall be removed when it reaches one
-
third of the barrier height.
Referenc
es
Stormwater Quality Handbooks
-
Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003
.
ATTACHMENT 7
Solid Waste Management
WM
-5
January 2011
California Stormwater BMP Handbook
1 of
4 Construction
www.casqa.org
Description and Purpose
Solid waste management procedures and practices are designed to prevent or reduce the discharg
e of pollutants to stormwater
from solid or construction waste by providing designated waste collection areas and containers, arranging for regular disposal, and training employees and subcontractors.
Suitable Applications
This BMP is suitable for construc
tion sites where the following
wastes are generated or stored:
Solid waste generated from trees and shrubs removed
during land clearing, demolition of existing structures (rubble), and building construction
Packaging materials including wood, paper, and pl
astic
Scrap or surplus building materials including scrap metals, rubber, plastic, glass pieces
,
and masonry products
Domestic wastes including food containers such as beverage cans, coffee cups, paper bags, plastic wrappers, and
cigarettes
Construction wa
stes including brick, mortar, timber, steel
and metal scraps, pipe and electrical cuttings, non
-
hazardous equipment parts, styrofoam and other materials used to transport and package construction materials
Highway planting wastes, including vegetative mate
rial,
Categories
EC
Erosion Control
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non
-
Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
Primary Objective
Secondary Objective
Target
ed Constituents
Sediment
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
ATTACHMENT 7
Solid Waste Management
WM
-5
January 2011
California Stormwater BMP Handbook
2 of
4 Construction
www.casqa.org
plant containers, and packaging materials
Limitations
Temporary stockpiling of certain construction wastes may not necessitate stringent drainage related controls during the non
-
rainy season or in desert areas with low rainfall.
Implementation
The fo
llowing steps will help keep a clean site and reduce stormwater pollution:
Select designated waste collection areas onsite.
Inform trash
-
hauling contractors that you will accept only watertight dumpsters for onsite use. Inspect dumpsters for leaks and repair any dumpster that is not watertight.
Locate containers in a covered area or in a secondary containment.
Provide an adequate number of containers with lids or covers that can be placed over the container to keep rain out or to prevent loss of wastes whe n it is windy.
Cover waste containers at the end of each work day and when it is raining.
Plan for additional containers and more frequent pickup during the demolition phase of construction.
Collect site trash daily, especially during rainy and windy condi tions.
Remove this solid waste promptly since erosion and sediment control devices tend to collect litter.
Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris.
Do not hose out dumpsters on the construction site. Leave dumpster cleaning to the trash hauling contractor.
Arrange for regular waste collection before containers overflow.
Clean up immediately if a con
tainer does spill.
Make sure that construction waste is collected, removed, and disposed of only at authorized disposal areas.
Education
Have the contractor’s superintendent or representative oversee and enforce proper solid waste management procedures and
practices.
Instruct employees and subcontractors on identification of solid waste and hazardous waste.
Educate employees and subcontractors on solid waste storage and disposal procedures.
ATTACHMENT 7
Solid Waste Management
WM
-5
January 2011
California Stormwater BMP Handbook
3 of
4 Construction
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Hold regular meetings to discuss and reinforce disposal procedures (incorporate into regular safety meetings).
Require that employees and subcontractors follow solid waste handling and storage procedures.
Prohibit littering by employees, subcontractors, and visitors.
Minimize production of solid waste materials wherever p ossible.
Collection, Storage, and Disposal
Littering on the project site should be prohibited.
To prevent clogging of the storm drainage system, litter and debris removal from drainage grates, trash racks, and ditch lines should be a priority.
Trash recept
acles should be provided in the contractor’s yard, field trailer areas, and at locations where workers congregate for lunch and break periods.
Litter from work areas within the construction limits of the project site should be collected and placed in water
tight dumpsters at least weekly, regardless of whether the litter was generated by the contractor, the public, or others. Collected litter and debris should not be placed in or next to drain inlets, stormwater drainage systems, or watercourses.
Dumpsters
of sufficient size and number should be provided to contain the solid waste generated by the project.
Full dumpsters should be removed from the project site and the
contents should be disposed
of by the trash hauling contractor.
Construction debris and was
te should be
removed from the site biweekly or more frequently
as needed.
Construction material visible to the public should be stored or stacked in an orderly manner.
Stormwater runon should be prevented from contacting stored solid waste through the use of berms, dikes, or other temporary diversion structures or through the use of measures to elevate waste from site surfaces.
Solid waste storage areas should be located at least 50 ft from drainage facilities and watercourses and should not be located in a
reas prone to flooding or ponding.
Except during fair weather, construction and highway planting waste not stored in watertight dumpsters should be securely covered from wind and rain by covering the waste
with tarps or plastic.
Segregate potentially hazar
dous waste from non
-
hazardous construction site waste.
Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris.
ATTACHMENT 7
Solid Waste Management
WM
-5
January 2011
California Stormwater BMP Handbook
4 of
4 Construction
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For disposal of hazardous waste, see WM
-
6, Hazardous Waste Management. Have
hazardous waste hauled to an appropriate disposal and/or recycling facility.
Salvage or recycle useful vegetation debris, packaging and surplus building materials when practical.
For example, trees and shrubs from land clearing can be used as a brush barrier, or converted into wood chips, then used as mulch on graded areas. Wood pallets, cardboard boxes, and construction scraps can also be recycled.
Costs
All of the above are low
cost measures.
Inspection and Maintenance
Inspect and verify that activity
–
based BMPs are in place prior to the commencement of
associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit
requirements for the associated project type and risk
level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Inspect BMPs subject t
o non
-
stormwater discharge daily while non
-
stormwater discharges
occur
Inspect construction waste area regularly.
Arrange for regular waste collection.
References
Processes, Procedures and Methods to Control Pollution Resulting
from
A
ll Construction
Activi
ty, 430/9
-
73 -
007, USEPA, 1973.
Stormwater Quality Handbooks
-
Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.
Stormwater Management for Construction Activities; Developi ng Pollution Prevention Plans
and Best Management Practice, EPA 832
-R-
92005; USEPA, April 1992.
ATTACHMENT 7
Hazardous Waste Manag
ement
WM
-6
January 2011
California Stormwater BMP Handbook
1 of
6 Construction
www.casqa.org
Description and Purpose
Prevent or reduce the discharge of pollutants to stormwater from hazardous waste through proper material use, waste disposal, and training of employees and subcontractors.
Suitable Applications
This best management practice (BMP) applies to all construction projects. Hazardous waste management practices are
imp
lemented on construction projects that generate waste from the use of:
Categories
EC
Erosion Control
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non
-
Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
Primary Objective
Secondary Objective
Target
ed Constituents
Sediment
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
Petroleum Products
Asphalt Products
Concrete Curing Compounds
Pesticides
Palliatives
Acids
Septic Wastes
Paints
Stains
Solvents
Wood Preservatives
Roof
ing Tar
Any materials deemed a hazardous waste in California,
Title 22 Division 4.5, or listed in 40 CFR Parts 110, 117, 261, or 302
ATTACHMENT 7
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In addition, sites with existing structures may contain wastes, which must be disposed of in accordance with federal, state, and local regulations. These wastes include:
Sandblasting
grit mixed with lead
-
, cadmium
-
, or chromium
-
based paints
Asbestos
PCBs (particularly in older transformers)
Limitations
Hazardous waste that cannot be reused or recycled must be disposed of by a licensed hazardous waste hauler.
Nothing in this BMP relieves the contractor from responsibility for compliance with federal, state, and local laws regarding storage, handling, transportation, and disposal of hazardous wastes.
This BMP does not cover aerially deposited lead (ADL) soils. For ADL soils refer to WM -7
,
Contaminated Soil Management.
Implementation
The following steps will help reduce stormwater pollution from hazardous wastes:
Material Use
Wastes should be stored in sealed containers constructed of a suitable material and should be labeled as required b
y Title 22 CCR, Division 4.5 and 49 CFR Parts 172, 173, 178, and 179.
All hazardous waste should be stored, transported, and disposed as required in Title 22 CCR, Division 4.5 and 49 CFR 261
-
263.
Waste containers should be stored in temporary containment f acilities that should comply
with the following requirements:
Temporary containment facility should provide for a spill containment volume equal to
1.5 times the volume of all containers able to contain precipitation from a 25 year storm event, plus the gr
eater of 10% of the aggregate volume of all containers or 100% of the capacity of the largest tank within its boundary, whichever is greater.
Temporary containment facility should be impervious to the materials stored there for a minimum contact time of 72
hours.
Temporary containment facilities should be maintained free of accumulated rainwater and spills. In the event of spills or leaks, accumulated rainwater and spills should be placed into drums after each rainfall. These liquids should be handled as a hazardous
waste unless testing determines them to be non
-
hazardous. Non
-
hazardous liquids
should be sent to an approved disposal site.
Sufficient separation should be provided between stored containers to allow for spill cleanup and emergency response a
ccess.
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Incompatible materials, such as chlorine and ammonia, should not be stored in the same temporary containment facility.
Throughout the rainy season, temporary containment facilities should be covered during non
-
working days, and prior to rain events.
Covered facilities may include use of plastic
tarps for small facilities or constructed roofs with overhangs.
Drums should not be overfilled
and wastes should not be mixed.
Unless watertight, containers of dry waste should be stored on pallets.
Do not ov
er
-
apply herbicides and pesticides. Prepare only the amount needed. Follow the recommended usage instructions. Over application is expensive and environmentally harmful. Apply surface dressings in several smaller applications, as opposed to one large a
pplication. Allow time for infiltration and avoid excess material being carried offsite by runoff. Do not apply these chemicals just before it rains. People applying pesticides must be certified in accordance with federal and state regulations.
Paint brushes and equipment for water and oil based paints should be cleaned within a contained area and should not be allowed to contaminate site soils, watercourses, or drainage systems. Waste paints, thinners, solvents, residues, and sludges that cannot be rec
ycled or reused should be disposed of as hazardous waste. When thoroughly dry, latex paint and paint cans, used brushes, rags, absorbent materials, and drop cloths should be disposed of as solid waste.
Do not clean out brushes or rinse paint containers into the dirt, street, gutter, storm drain, or stream. “Paint out” brushes as much as possible. Rinse water -
based paints to the
sanitary sewer. Filter and reuse thinners and solvents. Dispose of excess oil -
based paints
and sludge as hazardous waste.
The
following actions should be taken with respect to temporary contaminant:
Ensure that adequate hazardous waste storage volume is available.
Ensure that hazardous waste collection containers are conveniently located.
Designate hazardous waste storage areas o
nsite away from storm drains or watercourses
and away from moving vehicles and equipment to prevent accidental spills.
Minimize production or generation of hazardous materials and hazardous waste on the job site.
Use containment berms in fueling and maintenance areas and where the potential for spills is high.
Segregate potentially hazardous waste from non
-
hazardous construction site debris.
Keep liquid or semi
-
liquid hazardous waste in appropriate containers (closed drums or similar) and under cover.
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Clear
ly label all hazardous waste containers with the waste being stored and the date of accumulation.
Place hazardous waste containers in secondary containment.
Do not allow potentially hazardous waste materials to accumulate on the ground.
Do not mix wastes.
Use all of the product before disposing of the container.
Do not remove the original product label; it contains important safety and disposal information.
Waste Recycling Disposal
Select designated hazardous waste collection areas onsite.
Hazardous materials and wastes should be stored in covered containers and protected from vandalism.
Place hazardous waste containers in secondary containment.
Do not mix wastes, this can cause chemical reactions, making recycling impossible and complicating disposal.
Recyc
le any useful materials such as used oil or water
-
based paint.
Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris.
Arrange for regular waste collection before containers overflow.
Make sure that hazardous waste (e.g., excess oil
-
based paint and sludge) is collected,
removed, and disposed of only at authorized disposal areas.
Disposal Procedures
Waste should be disposed of by a licensed hazardous waste transporter at an authorized and licensed disposal facility or recycling facility utilizing properly completed Uniform H
azardous Waste Manifest forms.
A Department of Health Services certified laboratory should sam ple waste to determine the
appropriate disposal facility.
Properly dispose of rainwater in secondary containment that may have mixed with hazardous waste.
Attention is directed to "Hazardous Material", "Contaminated Material", and "Aerially Deposited Lead"
of the contract documents regarding the handling and disposal of hazardous materials.
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Education
Educate employees and subcontractors on hazardous waste storage and disposal procedures.
Educate employees and subcontractors on potential dangers to humans an d the
environment from hazardous wastes.
Instruct employees and subcontractors on safety procedures for common construction site hazardous wastes.
Instruct employees and subcontractors in identification of hazardous and solid waste.
Hold regular meetings to discuss and reinforce hazardous waste management procedures (incorporate into regular safety meetings).
The contractor’s superintendent or representative should oversee and enforce proper hazardous waste management procedures and practices.
Make sure tha
t hazardous waste is collected, removed, and disposed of only at authorized disposal areas.
Warning signs should be placed in areas recently treated with chemicals.
Place a stockpile of spill cleanup materials where it will be readily accessible.
If a cont
ainer does spill, clean up immediately.
Costs
All of the above are low cost measures.
Inspection and Maintenance
Inspect and verify that activity
–
based BMPs are in place prior to the commencement of
associated activities. While activities associated with the BMP are under way,
inspect BMPs
in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain e
vents, and after the conclusion of rain events.
.
Inspect BMPs subject to non
-
stormwater discharge daily while non
-
stormwater discharges
occur
Hazardous waste should be regularly collected.
A foreman or construction supervisor should monitor onsite hazardous waste storage and disposal procedures.
Waste storage areas should be kept clean, well organized, and equipped with ample cleanup supplies as appropriate for the materials being stored.
Perimeter controls, containment structures, covers, and liners should
be repaired or
replaced as needed to maintain proper function.
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Hazardous spills should be cleaned up and reported in conformance with the applicable Material Safety Data Sheet (MSDS) and the instructions posted at the project site.
The National Response C
enter, at (800) 424
-
8802, should be notified of spills of federal
reportable quantities in conformance with the requirements in 40 CFR parts 110, 117, and 302. Also notify the Governors Office of Emergency Services Warning Center at ( 916
) 8
45 -
8911
.
A copy
of the hazardous waste manifests should be provided.
References
Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995.
Processes, Procedures and Methods to Control Pollution Resulting from All Construction Activity, 430/9
-
73 -
007, USEPA, 1973
.
Stormwater Quality Handbooks
-
Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.
Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832
-R-
92005; USEPA, April 1992.
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Description and Purpose
Proper sanitary and septic waste management prevent the discharge of pollutants to stormw
ater from sanitary and septic
waste by providing convenient, well-maintained facilities, and arranging for regular
service and disposal.
Suitable Applications
Sanitary septic waste management practices are suitable for use at all construction sites that us
e temporary or portable sanitary
and septic waste systems.
Limitations
None identified.
Implementation
Sanitary or septic wastes should
be treated or disposed of in
accordance with state and local requirements. In many cases, one contract with a local facility
supplier will be all that it takes
to make sure sanitary wastes are properly disposed.
Storage and Disposal Procedures
Temporary sanitary facilities
should be located away from
drainage facilities, watercourses, and from traffic
circulation. If site conditions
allow, place portable facilities
a minimum of 50 feet from drainage conveyances and
traffic areas. When subjected to high winds or risk of high winds, temporary sanitary facili
ties should be secured to
prevent overturning.
Categories
EC
Erosion Control
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
;
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
Nutrients
;
Trash
;
Metals
Bacteria
;
Oil and Grease
Organics
;
Potential Alternatives
None
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Temporary sanitary facilities must be equippe
d with containment to prevent discharge of
pollutants to the stormwater drainage system of the receiving water.
Consider safety as well as
environmental implicat
ions before placing temporary sanitary
facilities.
Wastewater should not be discharged
or buried within the project site.
Sanitary and septic systems that discharge di
rectly into sanitary sewer systems, where
permissible, should comply with the local he
alth agency, city, county, and sewer district
requirements.
Only reputable, licensed sanitary and septic waste haulers should be used.
Sanitary facilities should be located in a convenient location.
Temporary septic systems should treat wastes
to appropriate levels before discharging.
If using an onsite disposal system (OSDS), su
ch as a septic system, local health agency
requirements must be followed.
Temporary sanitary facilities that discharge to
the sanitary sewer system should be properly
connected to avoid illicit discharges.
Sanitary and septic facilities should be main
tained in good workin
g order by a licensed
service.
Regular waste collection by a licensed hauler should be arranged before facilities overflow.
If a spill does occur from a temporary sanita
ry facility, follow fe
deral, state and local
regulations for containment and clean-up.
Education
Educate employees, subcontractors, and suppliers
on sanitary and septic waste storage and
disposal procedures.
Educate employees, subcontractors, and supplie
rs of potential dangers to humans and the
environment from sanitary and septic wastes.
Instruct employees, subcontractors, and suppliers
in identification of sanitary and septic
waste.
Hold regular meetings to discuss and reinforce the use of sanitary facilities (incorporate into regular safety meetings).
Establish a continuing education prog
ram to indoctrinate new employees.
Costs
All of the above are low cost measures.
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Inspection and Maintenance
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Arrange for regular waste collection.
If high winds are expected, portable sanitary facilities must be secured with spikes or weighed down to prevent over turning.
If spills or leaks from sanitary or septic faci
lities occur that are not contained and discharge
from the site, non-visibl
e sampling of site discharge may be required. Refer to the General Permit or to your project specific Constructi
on Site Monitoring Plan to determine if and
where sampling is required.
References
Stormwater Quality Handbooks - Construction Si
te Best Management Pr
actices (BMPs) Manual,
State of California Department of Transportation (Caltrans), March 2003.
Stormwater Management for Construction Activi
ties; Developing Pollution Prevention Plans
and Best Management Practice, EPA
832-R-92005; USEPA, April 1992.
ATTACHMENT 7
Wind Erosion Control
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Description and Purpose
Wind erosion or dust control cons
ists of applying water or other
chemical dust suppressants as necessary to prevent or alleviate dust nuisance generated by construction activities. Covering small stockpiles or areas is an
alternative to applying water or
other dust palliatives.
California’s Mediterranean climate, with a short “wet” season and a typically long, hot “dry” season, allows the soils to thoroughly dry out. During the dry season, construction activities are at their peak, an
d disturbed and exposed areas are
increasingly subject to wind erosion, sediment tracking and dust generated by construction equipment. Site conditions and climate can make dust control mo
re of an erosion problem than
water based erosion. Additionally, many local agencies, including Air Quality Manageme
nt Districts, require dust
control and/or dust control perm
its in order to comply with
local nuisance laws, opacity laws
(visibility impairment) and the
requirements of the Clean Air Act. Wind erosion control is required to be implemented at all construction sites greater than 1 acre by the General Permit.
Suitable Applications
Most BMPs that provide protecti
on against water-based erosion
will also protect against wind-based erosion and dust control requirements required by other agencies will generally meet wind erosion control requirements for wa
ter quality protection. Wind
erosion control BMPs are suitable du
ring the following construction
activities:
Categories
EC
Erosion Control
SE
Sediment Control
:
TC
Tracking Control
WE
Wind Erosion Control
;
NS
Non-Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
;
Primary Category
:
Secondary Category
Targeted Constituents
Sediment
;
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
EC-5 Soil Binders
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Construction vehicle traffic on unpaved roads
Drilling and blasting activities
Soils and debris storage piles
Batch drop from front-end loaders
Areas with unstabilized soil
Final grading/site stabilization
Limitations
Watering prevents dust only for a short period
(generally less than a few hours) and should
be applied daily (or more
often) to be effective.
Over watering may cause erosion and track-out.
Oil or oil-treated subgrade shou
ld not be used for dust control because the oil may migrate into drainageways and/or seep into the soil.
Chemical dust suppression agents may have
potential environmental impacts. Selected
chemical dust control agents should be environmentally benign.
Effectiveness of controls depends on soil, temp
erature, humidity, wind velocity and traffic.
Chemical dust suppression agents should not be
used within 100 feet of wetlands or water
bodies.
Chemically treated subgrades may make the soil
water repellant, interfering with long-term
infiltration and the vegetation/re-vegetation of
the site. Some chemical dust suppressants
may be subject to freezing and may contain
solvents and should be handled properly.
In compacted areas, watering and other liquid
dust control measures may wash sediment or
other constituents into the drainage system.
If the soil surface has minimal natural moisture, the affected area may need to be pre-wetted so that chemical dust control agents ca
n uniformly penetrate the soil surface.
Implementation
Dust Control Practices
Dust control BMPs generally stabilize exposed surf
aces and minimize activities that suspend or
track dust particles. The following table presents
dust control practices that can be applied to
varying site conditions that co
uld potentially cause dust. For heavily traveled and disturbed areas, wet suppression (watering), chemical dust suppression, gravel asphalt surfacing, temporary gravel construction entrances, equipm
ent wash-out areas, and haul truck covers can
be employed as dust control applications. Permanent or temporary vegetation and mulching can be employed for areas of occa
sional or no construction traffic. Preventive measures include minimizing surface areas to be di
sturbed, limiting onsite vehicle traffic to 15 mph or less, and controlling the number and activity of vehicles on a site at any given time.
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Chemical dust suppressants include: mulch and fi
ber based dust palliatives (e.g. paper mulch
with gypsum binder), salts and brines (e.g
. calcium chloride, magnesium chloride), non-
petroleum based organics (e.g. ve
getable oil, lignosulfonate),
petroleum based organics (e.g.
asphalt emulsion, dust oils, petrol
eum resins), synthetic polymers (e.g. polyvinyl acetate, vinyls, acrylic), clay additives (e.g. bentonite, montim
orillonite) and electroc
hemical products (e.g.
enzymes, ionic products).
Site
Condition
Dust
Control
Practices
Permanent
Vegetation
Mulching
Wet
Suppression
(Watering)
Chemical
Dust
Suppression
Gravel
or
Asphalt
Temporary Gravel
Construction
Entrances/Equipment
Wash Down
Synthetic
Covers
Minimize
Extent of
Disturbed
Area
Disturbed
Areas not
Subject to
Traffic
X X X X X X
Disturbed
Areas
Subject to
Traffic
X X X X X
Material
Stockpiles
X X X X X
Demolition
X X X
Clearing/
Excavation
X X X
Truck
Traffic on
Unpaved
Roads
X X X X X
Tracking
X X
Additional preventive measures include:
Schedule construction activities to minimi
ze exposed area (see
EC-1, Scheduling).
Quickly treat exposed soils using water, mu
lching, chemical dust suppressants, or
stone/gravel layering.
Identify and stabilize key access points prior to commencement of construction.
Minimize the impact of dust by anticipa
ting the direction of prevailing winds.
Restrict construction traffic to stabilized road
ways within the project
site, as practicable.
Water should be applied by means of pressure-t
ype distributors or pipelines equipped with a
spray system or hoses and nozzles th
at will ensure even distribution.
All distribution equipment should be equi
pped with a positive means of shutoff.
Unless water is applied by means
of pipelines, at least one mobile
unit should be available at
all times to apply water or dust palliative to the project.
If reclaimed waste water is used, the sour
ces and discharge must meet California
Department of Health Services
water reclamation criteria an
d the Regional Water Quality
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Control Board (RWQCB) requirements. Non-pota
ble water should not be conveyed in tanks
or drain pipes that will be used to convey po
table water and there should be no connection
between potable and non-pota
ble supplies. Non-potable
tanks, pipes, and other
conveyances should be marked, “NON-POTABLE WATER - DO NOT DRINK.”
Pave or chemically stabilize access points wher
e unpaved traffic surfaces adjoin paved roads.
Provide covers for haul trucks transporti
ng materials that contribute to dust.
Provide for rapid clean up of sediments depo
sited on paved roads. Furnish stabilized
construction road entrances and wheel wash areas.
Stabilize inactive areas of construction si
tes using temporary vegetation or chemical
stabilization methods.
For chemical stabilization, ther
e are many products available fo
r chemically stabilizing gravel
roadways and stockpiles. If chem
ical stabilization is used, the
chemicals should not create any
adverse effects on stormwater, plant life, or
groundwater and should meet all applicable
regulatory requirements.
Costs
Installation costs for water and
chemical dust suppression vary based on the method used and the length of effectiveness. Annual costs may be high since some of these measures are effective for only a few hours to a few days.
Inspection and Maintenance
Inspect and verify that activity-based BMPs
are in place prior to the commencement of
associated activities.
BMPs must be inspected in accordance with Ge
neral Permit requiremen
ts for the associated
project type and risk level. It is recomm
ended that at a minimum, BMPs be inspected
weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
Check areas protected to ensure coverage.
Most water-based dust control measures requir
e frequent application, often daily or even
multiple times per day. Obtain vendor or in
dependent information on
longevity of chemical
dust suppressants.
References
Best Management Practices and Erosion Control
Manual for Construction Sites, Flood Control
District of Maricopa County
, Arizona, September 1992.
California Air Pollution Control Laws, Califo
rnia Air Resources Boa
rd, updated annually.
Construction Manual, Chapter 4, Section 10, “Dus
t Control”; Section 17, “Watering”; and Section
18, “Dust Palliative”, California Department
of Transportation (Caltrans), July 2001.
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Prospects for Attaining the State Ambient Air
Quality Standards for Suspended Particulate
Matter (PM10), Visibility Reduci
ng Particles, Sulfates, Lead, and Hydrogen Sulfide, California Air Resources Board, April 1991.
Stormwater Quality Handbooks Co
nstruction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.
ATTACHMENT 7
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Description and Purpose
Street sweeping and vacuuming includes use of self
-
propelled
and walk
-
behind equipment to remove
sediment from streets
and roadways, and to clean paved surfaces in preparation for final paving. Sweeping and vacuuming prevents sediment from the project site from entering storm drains or receiving waters.
Suitable Applications
Sweeping and vacuuming a
re suitable anywhere sediment is
tracked from the project site onto public or private paved streets and roads, typically at points of egress. Sweeping and vacuuming are also applicable during preparation of paved surfaces for final paving.
Limitations
Swe
eping and vacuuming may not be effective when sediment
is wet or when tracked soil is caked (caked soil may need to be scraped loose).
Implementation
Controlling the number of points where vehicles can leave the site will allow sweeping and vacuuming effor
ts to be
focused, and perhaps save money.
Inspect potential sediment tracking locations daily.
Visible sediment tracking should be swept or vacuumed on a daily basis.
Do not use kick brooms or sweeper attachments. These
tend to spread the dirt rather than
remove it.
Categories
EC
Erosion Control
SE
Sediment Control
TC
Tracking Control
WE
Wind Erosion Control
NS
Non
-
Stormwater
Management Control
WM
Waste Management and
Materials Pollution Control
Legend:
Primary Objective
Secondary Objective
Targe
ted Constituents
Sediment
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics
Potential Alternatives
None
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If not mixed with debris or trash, consider incorporating the removed sediment back into the project
Costs
Rental rates for self
-
propelled sweepers vary depending on hopper size and duration of rental.
Expect rental rates from $58/hour (3 yd
3 hopper) to $88/hour (9 yd
3 Inspection and Ma
intenance
hopper), plus operator
costs. Hourly production rates vary with the amount of area to be swept and amount of sediment. Match the hopper size to the area and expect sediment load to minimize time spent dumping.
Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and a fter the conclusion of rain
events.
When actively in use, points of ingress and egress must be inspected daily.
When tracked or spilled sediment is observed outside the construction limits, it must be removed at least daily. More frequent removal, even continuous removal, may be required in some jurisdictions.
Be careful not to sweep up any unknown substance or any object that may be potentially hazardous.
Adjust brooms frequently; maximize efficiency of sweeping operations.
After sweeping is finished, pro
perly dispose of sweeper wastes at an approved dumpsite.
References
Stormwater Quality Handbooks
-
Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.
Labor Surcharge and Equipment Rental Rates, State of California Department of Transportation (Caltrans), April 1, 2002
–
March 31, 2003.
ATTACHMENT 7