109-Attachment 8. Summary of Mitigation Methods.pdfAttachment 8
SUMMARY OF MITIGATION MEASURES FOR U-2011-04, ASA-2011-05, EXC-2011-05 and EA-2011-04:
Air Quality, Item B:
Temporary Air Quality Impacts
• Water all active construction areas at least twice daily and more often during windy periods to
prevent visible dust from leaving the site; active areas adjacent to windy periods; active areas
adjacent to existing land uses shall be kept damp at all times, or shall be treated with non -toxic
stabilizers or dust palliatives.
• Cover all trucks hauling soil, sand, and other loose materials or require all trucks to maintain at
least 2 feet of freeboard;
• Sweep daily (or more often if necessary) to prevent visible dust from leaving the site (preferably
with water sweepers) all paved access roads, parking areas, and staging areas at construction
sites; water sweepers shall vacuum up excess water to avoid runoff -related impacts to water
quality; and
• Sweep streets daily, or more often if necessary (preferably with water sweepers) if visible soil
material is carried onto adjacent public streets.
• The applicant shall incorporate the City's construction best management practices into the
building permit plan set.
Hydrology and Water Quality, Item A, B, F, E:
Prior to Construction
Project drainage shall be provided to the satisfaction of the Public Works Department.
Prior to the issuance of a Building Permit, if required by the Public Works Department, the
applicant must provide details of specific Best Management Practices (BMPs), including, but not
limited to, bioswales, disconnected downspouts that drain to landscape areas, direct roof runoff
into rain barrels or cisterns for onsite irrigation reuse, pervious paving materials and
native/drought-tolerant landscaping to reduce impervious surface areas, project areas should be
dry -swept routinely and onsite litter should be picked -up and disposed of properly, onsite inlets
and catch basins that area stenciled "No Dumping — Flows to Bay," etc., to the satisfaction of the
Director of Public Works.
The project shall comply with Provision C.3 of NPDES Permit Number CAS612008, which
provides enhanced performance standards for the management of stormwater of new
development and redevelopment.
The project shall comply with applicable provisions of City Policies which establishes guidelines
and minimum BMPs for all projects and provides for numerically -sized (or hydraulically -sized)
TCMs for projects that create and/or replace 10,000 sq. ft. or more of impervious surface or are
considered a "Land Use of Concern" and 2) Post -Construction Hydromodification Policy which
requires the incorporation of measures to control hydoomodification impacts resulting from new
development and redevelopment projects where such hydromodification is likely to cause
increased erosion, silt pollutant generation or other adverse impacts to local rivers and creeks.
Construction Measures, if required
• Prior to the commencement of any clearing, grading or excavation, the project shall comply with the
State Water Resources Control Board's National Pollutant Discharge Elimination System (NPDES)
General Construction Activities Permit, to the satisfaction of the Director of Public Works, as follows:
1-153
1. The applicant shall develop, implement and maintain a Storm Water Pollution Prevention
Plan (SWPPP) to control the discharge of stormwater pollutants including sediments
associated with construction activities;
2. The applicant shall file a Notice of Intent (NO1) with the State Water Resources Control
Board (SWRCB).
The project shall incorporate Best Management Practices (BMPs) into the project to control the
discharge of stormwater pollutants including sediments associated with construction activities.
Examples of BMPs are contained in the publication Blueprint for a Clean Bay. For additional
information about the Erosion Control Plan, the NPDES Permit requirements or the documents
mentioned above, please call the Department of Public Works.
Noise, Item D:
Temporary Noise Levels during Construction
• Construction will be limited to the hours of 7:00 a.m. to 8:00 p.m. Monday through Friday for any on -
site or off -site work within 500 feet of any residential unit. Construction outside of these hours may be
approved through a development permit based on a site -specific construction noise mitigation plan and
a finding by the Community Development Director that the construction noise mitigation plan is
adequate to prevent noise disturbance of affected residential uses.
• Weekend construction hours, including staging of vehicles, equipment and construction materials,
shall be limited between the hours of 9 a.m. to 5 p.m. Permitted work activities shall be conducted
exclusively within the interior of enclosed building structures provided that such activities are
inaudible to existing adjacent residential uses. The developer shall be responsible for educating all
contractors and subcontractors of said construction restrictions. Rules and regulation pertaining to
all construction activities and limitations identified in this permit, along with the name and
telephone number of a developer appointed disturbance coordinator, shall be posted in a
prominent location at the entrance to the job site. The Community Development Director may
rescind provisions to allow extended hours of construction activities on weekends upon written
notice to the developer.
• The contractor shall use "new technology" power construction equipment with state-of-the-art
noise shielding and muffling devices. All internal combustion engines used on the project site shall
be equipped with adequate mufflers and shall be in good mechanical condition to minimize noise
created by faulty or poor maintained engines or other components.
• No individual device may produce a noise level more than eighty-seven dBA at a distance of 25 feet
(7.5 meters) or generate noise level on any nearby property that exceeds eighty dBA.
• Locate stationary noise generating equipment as far as possible from sensitive receptors. Staging
areas shall be located a minimum of 200 feet from noise sensitive receptors, such as residential
uses.
• The developer will implement a Construction Management Plan approved by the Community 41
Development Director to minimize impacts on the surrounding sensitive land uses to the fullest
extent possible. The Construction Management Plan would include the following measures to
minimize impacts of construction upon adjacent land uses:
a) Early and frequent notification and communication with the neighborhood of the construction
activities.
b) Prohibit unnecessary idling of internal combustion engines.
c) 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 (e.g., beginning work too early, bad muffler, etc.) and institute
1-154
reasonable measures warranted to correct the problem. A telephone number for the
disturbance coordinator would be conspicuously posted at the construction site.
d) Delineate the limits of development onsite.
e) Discuss construction -staging methods.
f) The plan shall demonstrate that emergency access along Mercedes Road shall not be impeded
at any time.
g) A garbage/debris container shall be placed on the site to store debris and the project site shall
be cleared of debris at the end of every day during project construction. The container shall be
emptied regularly such that no garbage is visible over the rim of the container. Only one
portable toilet shall be permitted on the construction site. The portable toilet shall be allowed
only during the period of project construction and shall be removed immediately after
completion of construction.
Transportation/Traffic, Item A, B:
increase in Traffic, Level of Service:
• Install a median in the right of way on Stevens Creek Boulevard to prevent left turns out of Stern
Avenue as discussed in the Traffic Impact Analysis prepared by Hexagon Transportation Consultants,
Inc and depicted on Page 27 thereof
3
1-155