HERCULES SKELLY ISMND MITIGATION MEASURES
MM AIR-1 Implement BAAQMD Best Management Practices During Construction
The following dust control measures, as recommended by the Bay Area Air Quality Management District (BAAQMD), shall be included in the design of the proposed project and implemented during construction:
• All exposed non-paved surfaces (e.g., parking areas, staging areas, soil piles, graded areas, and access roads) shall be watered at least two times per day and/or non-toxic soil stabilizers shall be applied to exposed non-paved surfaces.
• All haul trucks transporting soil, sand, or other loose material off-site shall be covered and/or shall maintain at least 2 feet of freeboard.
• All visible mud or dirt tracked out onto adjacent public roads shall be removed using wet power vacuum street sweepers at least once per day. The use of dry power sweeping is prohibited. • All vehicle speeds on unpaved roads shall be limited to 15 miles per hour. • All roadways, driveways, and sidewalks to be paved shall be completed as soon as possible. Building pads shall be laid as soon as possible after grading unless seeding or soil binders are used. • Idling times shall be minimized either by shutting equipment off when not in use or reducing the maximum idling time to 5 minutes, as required by the California Airborne Toxics Control Measure (ACTM) Title 13, Section 2485 of California Code of Regulations. Clear signage regarding idling restrictions shall be provided for construction workers at all access points. • All construction equipment shall be maintained and properly tuned in accordance with manufacturer’s specifications. All equipment shall be checked by a certified mechanic and determined to be running in proper condition prior to operation.
• The prime construction contractor shall post a publicly visible sign with the telephone number and person to contact regarding dust complaints. The City and the construction contractor shall take corrective action within 48 hours. The BAAQMD’s phone number shall also be visible to ensure compliance with applicable regulations.
MM BIO-1A Roosting Bats
• A qualified Biologist with relevant roosting bat experience shall conduct a survey for special-status bats during the appropriate time of day to maximize detectability to determine whether bat species are roosting near the work area no less than 7 days and no more than 14 days prior to beginning ground disturbance and/or construction. Survey methodology may include visual surveys of bats (e.g., observation of bats during foraging period), inspection for suitable habitat or bat sign (e.g., guano), or use of ultrasonic detectors (Anabat, etc.).
• Visual surveys shall include trees and structures within 500 feet of project construction activities (where accessible). Not more than 2 weeks prior to building demolition and/or tree removal, the project applicant shall ensure that a qualified Biologist (i.e., one familiar with the identification of bats and signs of bats) survey the trees and structures proposed for removal for the presence of roosting bats or evidence of bats. If no roosting bats or evidence of bats are found in the structure, removal may proceed. If the Biologist determines or presumes bats are present, the Biologist shall exclude the bats from suitable spaces by installing one-way exclusion devices. After the bats vacate the space, the Biologist shall close off the space to prevent recolonization. Structure and tree removal shall only commence after the Biologist verifies 7 to 10 days later that the exclusion methods have successfully prevented bats from returning. Bat exclusion shall only occur between February 15 and April 15, and from August 15 through October 30, to avoid impacts on non-volant (i.e., nonflying) individuals.
MM BIO-1B: Protection of Active Bird Nests (includes pre-construction survey and implementation of avoidance buffer, if found)
• If the project requires trees to be removed during the nesting season (usually February through August), a pre-construction survey shall be conducted no more than 7 days prior to the start of ground or vegetation disturbance (including tree removal) to determine whether or not active nests are present. • If an active nest is located during pre-construction survey, a qualified Biologist shall determine an appropriately sized avoidance buffer based on the species and anticipated disturbance level. (The California Department of Fish and Wildlife [CDFW] recommends a minimum no-disturbance buffer of 250 feet around active nests of non-listed bird species and a 500-foot no-disturbance buffer around active nests of non-listed raptors.) A qualified Biologist shall delineate the avoidance buffer using Environmentally Sensitive Area fencing, pin flags, and or yellow caution tape. The buffer zone shall be maintained around the active nest site(s) until the young have fledged and are foraging independently. No construction activities or construction foot traffic is allowed to occur within the avoidance buffer(s).
The qualified Biologist shall monitor the active nest during construction activities to prevent any potential impacts that may result from the construction of the proposed project, until the young have fledged.
MM BIO-1C: Overwintering Monarch Butterfly
Project activities such as vegetation removal, grading, or initial ground-disturbing activities shall be conducted between November 1 and July 31 (outside of the overwintering season) to the extent feasible. If such activities must be initiated during the overwintering season (August 1 through October 31), a pre-construction overwintering survey shall be conducted by a qualified Biologist no more than 7 days prior to vegetation removal, grading, or initial ground disturbance. The survey shall include the disturbance area and surrounding 250 feet to identify the location and status of any colonies that could potentially be affected either directly or indirectly by project activities. If no colonies are present, then project activities can commence as scheduled. If a colony is present, project construction shall cease immediately to avoid all direct and indirect impacts and report the presence of the colony to the United States Fish and Wildlife Service (USFWS) and California Department of Fish and Wildlife (CDFW) and follow all recommendations provided by USFWS and CDFW.
MM BIO-2: Avoidance and Minimization Measures for On-Site Aquatic Features • No work within the Riparian Corridor and Creek Banks or Bed. No work (including vegetation removal) shall take place within this area unless specifically permitted by California Department of Fish and Wildlife (CDFW), Regional Water Quality Control Board (RWQCB), or United States Army Corp of Engineers (USACE).
• Erosion Control: At no time shall silt-laden runoff be allowed to enter on-site aquatic features and their associated habitats. Erosion control measures shall be utilized throughout all phases of operation where sediment runoff from the project may enter these aquatic features. Best Management Practices (BMPs) to avoid erosion, uncontrolled stormwater runoff and bank deterioration shall be implemented, following the requirements of the proposed project’s Stormwater Control Plan, and typically include silt fencing, coir rolls, and/or straw bale dikes.
• Prevention of Toxic Substances/Pollution. No substances toxic to fish and wildlife shall be discharged or allowed to leach into the aquatic features present on-site. Reasonable precautions to protect aquatic habitats from pollution with harmful materials (e.g., fuels, oils, lubricants, and solvents) shall be implemented. Specifically, all potentially hazardous materials shall be controlled, cleaned up, and properly disposed of in accordance with the project’s water quality control permits and plans. Materials deleterious or toxic to fish and wildlife, including, but not limited to, asphalt, tires, concrete, construction materials, treated wood, and creosote containing materials, shall not be stockpiled within 150 feet any aquatic feature present on-site.
• Wildlife Exclusion Fencing and Monitoring. Wildlife Exclusion Fencing (WEF) shall be constructed around the entire perimeter of the project site and the northern riparian dripline associated with the perennial drainage, to prevent wildlife from entering the work area. A qualified Biologist shall be on-site to monitor the installation of WEF. WEF shall be in place and regularly maintained during project implementation.
Fencing shall be removed within 72 hours of completion of work, and temporarily impacted areas shall be restored to pre-project conditions.
MM BIO-3: Protection of Mature Trees (Tree Inventory and Replacement Plan) • The project applicant shall adhere to the requirements of the City’s tree ordinance (Title 4, Chapter 15), which includes a submittal of a Tree Replacement Plan to the City prior to the removal of trees and/or prior to the issuance of a demolition or grading permit. Prior to the submission of the Tree Replacement Plan, a certified arborist shall conduct a Tree Inventory to determine the number and type of trees scheduled to be removed.
• Following the completion of the Tree Inventory, a certified arborist shall complete the Tree Replacement Plan and shall designate the approximate locations, number, and sizes of trees to be planted. The Tree Replacement Plan shall include a minimum 1:1 replacement ratio for City-protected trees impacted by project construction.
MM CUL-1
An Archaeologist who meets the Secretary of the Interior’s Professional Qualification Standards for archaeology shall be present during the demolition of buildings at the site, grubbing and ground clearance, and during initial grading and project-related ground disturbance. Should exposed soils indicate archaeological resources may be present, archaeological monitoring of all project related ground disturbance will continue as determined necessary by the Archaeologist. In the event that buried cultural resources are discovered during construction, operations shall stop within a 100-foot radius of the find and a qualified Archaeologist shall be consulted to determine whether the resource requires further study. The qualified Archaeologist shall make recommendations to the lead agency on the measures that shall be implemented to protect the discovered resources, including but not limited to excavation of the finds and evaluation of the finds in accordance with Section 15064.5 of the CEQA Guidelines.
Potentially significant cultural resources consist of, but are not limited to, stone, bone, fossils, wood, or shell artifacts or features, including hearths, structural remains, or historical dumpsites. Any previously undiscovered resources found during construction within the project site should be recorded on appropriate California Department of Parks and Recreation (DPR) forms and evaluated for significance in terms of CEQA Guidelines.
If the resources are determined to be unique historical resources as defined under Section 15064.5 of the CEQA Guidelines, mitigation measures shall be identified by the monitor and recommended to the lead agency.
Appropriate mitigation measures for significant resources could include avoidance or capping, incorporation of the site in green space, parks, or open space, or data recovery excavations of the finds.
No further grading shall occur in the area of the discovery until the lead agency approves the measures to protect these resources. Any archaeological artifacts recovered as a result of mitigation shall be donated to a qualified scientific institution approved by the lead agency where they would be afforded long-term preservation to allow future scientific study.
MM CUL-2
Should previously unknown buried human remains be discovered during construction of the proposed project, Section 7050.5 of the California Health and Safety Code applies, and the following procedures shall be followed.
In the event of an accidental discovery or recognition of any human remains, Public Resources Code Section 5097.98 must be followed. In this instance, once project-related earthmoving begins, and if there is accidental discovery or recognition of any human remains, the following steps shall be taken:
1) There shall be no further excavation or disturbance of the site, or any nearby area reasonably suspected to overlie adjacent human remains until the County Coroner is contacted to determine whether the remains are Native American and if an investigation of the cause of death is required. If the Coroner determines the remains to be Native American, the Coroner shall contact the Native American Heritage Commission (NAHC) within 24 hours, and the NAHC shall identify the person or persons it believes to be the “most likely descendant” of the deceased Native American. The most likely descendant may make recommendations to the landowner or the person responsible for the excavation work, for means of treating or disposing of, with appropriate dignity, the human remains and any associated grave goods, as provided in Public Resources Code Section 5097.98, or
2) Where the following conditions occur, the landowner or his/her authorized representative shall rebury the Native American human remains and associated grave goods with appropriate dignity either in accordance with the recommendations of the most likely descendant or on the project area in a location not subject to further subsurface disturbance:
• The NAHC is unable to identify a most likely descendant, or the most likely descendant failed to make a recommendation within 48 hours after being notified by the Commission; • The descendant identified fails to make a recommendation; or • The landowner or his authorized representative rejects the recommendation of the descendant and mediation by the NAHC fails to provide measures acceptable to the landowner.
MM GEO-1
Prior to issuance of preliminary grading permits, the project applicant shall incorporate all recommendations provided in the project-Geotechnical Investigation into project plans. The Geotechnical recommendations outlined on Page 9 through Page 22 of the Geotechnical Investigation that shall be implemented include general earthwork recommendations for site preparation, removal of unsuitable soils, surface and subsurface drainage, bio-filtration facilities, foundations, concrete flatwork, retaining walls, spread and pier footings, pavement areas, utility trenches, project review, and construction monitoring. Additionally, these include recommendations related to structural design, foundation design, foundation systems, slabs, moisture barriers, seismic design, walls, footing excavations, slabs and walkways, concrete design, corrosion, pavement design, as well as lot maintenance, and future plan reviews.
MM GEO-2
Prior to the commencement of earth-disturbing activities, a professional paleontologist shall provide the construction crew with an orientation on significant fossils that could be encountered and the appropriate procedures to follow in the event of a discovery. If any vertebrate remains (i.e., bones, teeth, or unusually abundant and well-preserved invertebrates or plants) be unearthed, all work in the immediate vicinity of the discovery should be diverted at least 15 feet until a professional paleontologist assesses the find and, if deemed appropriate, salvages it in a timely manner. All recovered fossils shall be deposited in an appropriate repository, such as the University of California Museum of Paleontology (UCMP), where they shall be properly curated and made accessible for future study.
MM NOI-1
To reduce potential construction noise impacts, the following best management measures shall be implemented during all phases of construction. In addition, all of the following measures shall be printed on the project construction documents prior to issuance of building permits:
• The construction contractor shall limit noise producing construction activities, including deliveries and equipment warmup, to the hours between 7:00 a.m. to 7:00 p.m., Monday through Saturday. No noise producing construction activity shall be permitted on Sundays. • The construction contractor shall ensure that all equipment driven by internal combustion engines shall be equipped with mufflers, which are in good condition and appropriate for the equipment. • The construction contractor shall ensure that unnecessary idling of internal combustion engines (i.e., idling in excess of 5 minutes) is prohibited.
• The construction contractor shall utilize “quiet” models of air compressors and other stationary noise sources where such market available technology exists.
• At all times during project grading and construction, the construction contractor shall ensure that stationary noise-generating equipment shall be located as far as practicable, and a minimum of 50 feet, from sensitive receptors and placed so that emitted noise is directed away from the nearest residential land uses.
• Where a solid fence or wall is not already present along the property line of an adjoining residential land use, the construction contractor shall construct temporary, minimum 6-foot-high, solid noise barrier/fence with a minimum surface weight of 4 pounds per square foot, which would be effective to reduce construction noise by up to 5 A-weighted decibel (dBA). • The construction contractor shall designate a noise disturbance coordinator who would be responsible for responding to any local complaints about construction noise. The disturbance coordinator would determine the cause of the noise complaints (starting too early, bad muffler, etc.) and establish reasonable measures necessary to correct the problem. The construction contractor shall visibly post a telephone number for the disturbance coordinator at the construction site.
MM TRANS-1
During design review and prior to issuance of grading permits, the proposed grading plans shall be carefully evaluated to ensure that the finished grade and landscaping do not create any visual obstructions for vehicles exiting the driveway. Should the finished grade or landscaping create visual obstructions, the proposed landscaping shall be altered such that there would no longer be obstructions.