To: Liz Cullinan, Director of Building and Planning, Town of Hillsborough
Total Page:16
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2635 NORTH FIRST STREET SAN JOSE, CA 95134 650.327.0429 WWW.MIGCOM.COM Memo To: Liz Cullinan, Director of Building and Planning, Town of Hillsborough Paul Willis, Public Works Director/City Engineer, Town of Hillsborough CC: Mark Hudak, Law Offices of Mark D. Hudak From: Chris Dugan Date: June 26, 2017 SUBJECT: Revised Final IS/MND and MMRP for the Cal Water MPS Station 6 Potable Water Tank Replacement Project This memo transmits the Revised Final Mitigated Negative Declaration (MND), Initial Study (IS), and Mitigation Monitoring and Reporting Plan (MMRP) for the Cal Water MPS Station 6 Potable Water Tank Replacement Project. The Revised Final IS/MND and MMRP reflect new information contained in a pre-demolition hazardous materials survey report prepared for the Town in June 20171. The new information results in minor changes to the contents and information of the IS/MND and MMRP prepared for the Cal Water project in 2016. The changes to the IS/MND include revisions to Mitigation Measure AIR-1 (pertaining to fugitive dust) but do not substantially change the findings of the IS/MND and as such do not require public re-circulation of the IS/MND. This memo has the following attachments: • Attachment 1: Revised Final MND • Attachment 2: Revised Final MMRP • Attachment 3: Revised Final IS • Attachment 4: Revised Final IS Appendix H (Hazardous Material Survey) For clarity, text changes to the original IS are shown only in Attachment 3, where deleted text is identified in strikethrough and new text is identified in underline format. ##CPD 1 Terracon Consultants, Inc. (Terracon) 2017. Pre-Demolition Hazardous Materials Survey, Crystal Springs Reservoir, Station 6, Tank 1, Hillsborough, CA. June 13, 2017. Revised Final IS/MND and MMRP for the Cal Water MPS Station 6 Potable Water Tank Replacement Project This page intentionally left blank. MIG Memorandum June 26, 2017 Revised Final IS/MND and MMRP for the Cal Water MPS Station 6 Potable Water Tank Replacement Project Attachment 1 Revised Final Mitigated Negative Declaration (MND) for the Cal Water MPS Station 6 Potable Water Tank Replacement Project June 26, 2017 MIG Memorandum June 26, 2017 Revised Final IS/MND and MMRP for the Cal Water MPS Station 6 Potable Water Tank Replacement Project This page intentionally left blank. MIG Memorandum June 26, 2017 Attachment 1: Revised Final MND for the Cal Water Page 1 MPS Station 6 Potable Water Tank Replacement Project Cal Water MPS Station 6 Potable Water Tank Replacement Project Revised Mitigated Negative Declaration Project: Cal Water MPS Station 6 Potable Water Tank Replacement Project Project Proponent / Lead Agency: Town of Hillsborough Availability of Documents: The Initial Study for this Mitigated Negative Declaration is available for review at: Town of Hillsborough 1600 Floribunda Ave Hillsborough, CA 94010 (650) 799-8466 Contact – Elizabeth Cullinan, AICP, Director of Building and Planning PROJECT DESCRIPTION The California Water Supply Company (Cal Water) is the largest investor-owned American water utility west of the Mississippi River and is the third largest in the country. In the San Francisco Bay Area, Cal Water’s Bayshore District serves the cities of San Carlos, San Mateo, and South San Francisco. One of the Bayshore District’s facilities, the Mid-Peninsula District (MPS) Station 6, is located in the Town of Hillsborough, in San Mateo County. The MPS Station 6 site does not have a physical address, but consists of an approximately 1.9-acre parcel of land (Assessor’s Parcel Number [APN] 032-395-220) on Crystal Springs Road. The MPS Station 6 site is centered on 37°33'23" North latitude and 122°20'10" West longitude, and generally surrounded by residential properties. The existing water storage facilities at Cal Water’s MPS Station 6 site include a pump station (with three active pumps), an underground, concrete potable water tank with capacity to store approximately 2.8 million gallons of water, and associated site improvements, such as site utilities and landscaping. The existing water tank is generally in poor condition and was removed from service in 2005. Cal Water is proposing to deconstruct and replace the existing underground water tank with a new underground water tank that would have the capacity to store approximately 3.05 million gallons of water. The new tank would increase storage capacity within the Bayshore District and improve the efficiency and reliability of the District’s water distribution system, especially during a seismic-related event. Cal Water would not modify the exterior of the existing pump station, but would add new exterior lighting. Cal Water would also make other minor site improvements to accommodate the tank replacement project, such as adding and/or replacing piping and utility lines, re-paving the site’s access driveway, and installing a new perimeter fence and gate. Cal Water proposes to begin construction in fall 2016 and have the new tank in-service by summer 2018. Cal Water estimates the project would result in the loss of up to 33 trees from the site (out of more than 300 trees on-site) and result in the off-hauling of approximately 7,670 cubic yards of concrete and soil. PROPOSED FINDINGS Town of Hillsborough has reviewed the attached Initial Study and determined that the Initial Study identifies potentially significant project effects, but: 1. Revisions to the project plans incorporated herein as mitigation would avoid or mitigate the effects to a point where no significant effects would occur; and 2. There is no substantial evidence, in light of the whole record before the agency, that the project may have a significant effect on the environment. Pursuant to California Environmental Quality Act (CEQA) Guidelines Sections 15064(f)(3) and 15070(b), a Cal Water MPS Station 6 Potable Water Tank Replacement Project Town of Hillsborough Revised Final Mitigated Negative Declaration June 26, 2017 Attachment 1: Revised Final MND for the Cal Water Page 2 MPS Station 6 Potable Water Tank Replacement Project Mitigated Negative Declaration has been prepared for consideration as the appropriate CEQA document for the project. BASIS OF FINDINGS Based on the environmental evaluation presented in the attached Initial Study, the project would not cause significant adverse effects related to aesthetics, agricultural and forestry resources, cultural resources, geology and soils, greenhouse gas emissions, hazards and hazardous emissions, hydrology and water quality, land use and planning, mineral resources, noise, population and housing, public services, recreation, and utilities/service systems. The project does not have impacts that are individually limited, but cumulatively considerable. Design Features Cal Water has designed the proposed Cal Water MPS Station 6 Potable Water Tank Replacement Project to minimize potential impacts upon views and private property. Cal Water is proposing to replace the replace the existing underground tank with a new underground tank that is similar in size to the existing tank (less than 10 percent increase in storage capacity at the site). The underground tank design minimizes visual impacts to the homes around the MPS Station 6 site. Best Management Practices Cal Water has incorporated the following Best Management Practices into the planning, design, construction, operation and maintenance of its project to minimize the potential adverse effects of the project on the surrounding community and the environment. These Best Management Practices would be included in all construction bid requests, contracts, and documents, and are a part of the project and not mitigation measures. Best Management Practices Incorporated Into the Cal Water MPS Station 6 Potable Water Tank Replacement Project Hydrology and Due to the limited area of disturbance (approximately 0.9 acres), the Water Quality proposed project is not subject to the State Water Resources Control Board’s Construction General Permit and does not require the preparation of a formal Storm Water Pollution Prevention Plan; however, the proposed project is subject to the Town’s municipal code requirements to prepare a grading plan and a sediment control plan. To reduce the potential for site erosion and off-site sedimentation, the Cal Water and/or its contractor shall, to the maximum extent feasible: 1) Schedule grading and excavation work during forecasted dry weather and stabilize all disturbed areas as soon as feasible, but at a minimum prior to any forecast rain event. 2) Protect storm drain inlets with fabric and gravel bags and cover or surrounding stockpiles of soil with fiber rolls to prevent soil from migrating offsite. Noise Cal Water shall incorporate the following construction noise best management practices into the project: 1) All work shall be subject to the noise threshold and time limitations of the Hillsborough Municipal Code and shall be performed within approved working hours between (8 AM to 5 PM Monday to Friday). Signs shall be posted at the entrance to the site and at construction equipment staging areas informing all workers and construction contractors of Hillsborough Municipal Code requirements. The sign shall also provide a contact name and phone number for the job site Cal Water MPS Station 6 Potable Water Tank Replacement Project Town of Hillsborough Revised Final Mitigated Negative Declaration June 26, 2017 Attachment 1: Revised Final MND for the Cal Water Page 3 MPS Station 6 Potable Water Tank Replacement Project Noise (con’t) and the Hillsborough Department of Public Works. 2) Adjacent residences shall be given at least five days advanced written notice of construction activity scheduling and hours of construction. 3) Stationary equipment such as compressors, generators, and welder machines shall be located as far away from surrounding residential land uses as possible. 4) Impact tools such as jack hammers shall be hydraulically or electrically powered wherever possible to avoided noise associated with compressed air exhaust from pneumatically powered tools. When use of pneumatic tools is unavoidable, it shall be ensured the tool will not exceed a decibel limit of 85dBA at a distance of 50 feet.