New Cement Hill Pipeline Project
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Draft Initial Study/Proposed Mitigated Negative Declaration New Cement Hill Pipeline Project Prepared for: Suisun-Solano Water Authority October 2018 PROPOSED MITIGATED NEGATIVE DECLARATION PROJECT: NEW CEMENT HILL PIPELINE PROJECT LEAD AGENCY: SUISUN-SOLANO WATER AUTHORITY (SSWA) Under CEQA, the lead agency is the public agency with primary responsibility over approval of the project. SSWA is the CEQA lead agency because it is responsible for implementation and operation of the New Cement Hill Pipeline. PROJECT DESCRIPTION SUMMARY SSWA proposes to construct and operate the New Cement Hill Pipeline (proposed project) which would provide a second pipeline from the Cement Hill Water Treatment Plant (CHWTP) to two 2-million-gallon water storage tanks on Cement Hill. The primary intent of the project is to enhance the operation of the CHWTP by turning the tanks into flow-through clearwell storage for filtered water to improve the CHWTP reliability and regulatory compliance. The pipeline would be constructed of 20-inch diameter PVC pipe, and most of the pipeline would be underground, with a short aerial crossing of the Putah South Canal. Construction would predominantly be open-cut construction in an approximately 4-foot-wide by 5.5-foot-deep trench. After pipeline placement, the ground surface would be restored. Disturbed areas in roadways would be repaved. Construction of the pipeline is anticipated to begin in spring of 2019 and would take 85 to 105 calendar days. Construction would occur 5 days per week for a total of up to 9 hours per day. Construction activities on public roads would occur between 9 a.m. and 4 p.m. Work in streets would take about 10 working days. Most of the proposed project would be located in the City of Fairfield, California. The northern extent of the project, including where it connects to Tanks 2A and 2B, would be located in unincorporated Solano County. From Tanks 2A and 2B, the pipeline would generally follow the existing access road down to Clay Bank Road. The pipeline would then be located within Clay Bank Road and Moosup Court. It would cross over the Putah South Canal, and then onto the CHWTP property located north of Manuel Campos Parkway in north Fairfield. FINDINGS An Initial Study has been prepared to assess the project’s potential effects on the environment and the significance of those effects. Based on the Initial Study, it has been determined that the project would not have any significant effects on the environment once mitigation measures are implemented. The conclusion is supported by the following findings: 1. The project would have no impact related to agriculture and forestry resources, land use and planning, mineral resources, population and housing, public services, and recreation. 2. The project would have a less-than-significant impact on aesthetics, air quality, geology and soils, hydrology and water quality, and utilities and service systems. Suisun-Solano Water Authority New Cement Hill Pipeline Project IS/MND 1 Proposed Mitigated Negative Declaration Ascent Environmental 3. Mitigation is required to reduce potentially significant impacts related to biological resources, cultural resources, hazards and hazardous materials, noise, transportation and traffic, and tribal cultural resources to less-than-significant levels. Biological Resources Mitigation Measure 3.4-1: Avoid Elderberry Shrubs To maintain the health and vigor of elderberry shrubs, the shrubs will be avoided. Project activities may occur up to the dripline of elderberry shrubs if the following precautions are implemented to minimize the potential for indirect impacts: All areas to be avoided during construction activities will be fenced or flagged as close to construction limits as possible. A minimum avoidance area up to the dripline of each elderberry plant will be maintained to avoid direct impacts that could damage or kill the plant. Mitigation Measure 3.4-2: Nesting Raptor and Special-Status Bird Avoidance and Buffers Pre-construction surveys and active nest buffer zones. If construction activity is scheduled to occur during the Swainson’s hawk and other raptor nesting season (March 1 to August 31), the project proponent shall retain a qualified biologist to conduct preconstruction surveys and to identify active nests on and all publicly accessible areas within 0.25 mile of the project site that could be affected by on-site project construction. The surveys shall be conducted no less than 14 days and no more than 30 days before the beginning of construction for all project phases. Applicable guidelines provided in Recommended Timing and Methodology for Swainson’s Hawk Nesting Surveys in the Central Valley (Swainson’s Hawk Technical Advisory Committee 2000) shall be followed for surveys for Swainson’s hawk. If no nests are found, no further mitigation is required. If active nests are found, impacts on nesting Swainson’s hawks and other raptors shall be avoided by establishment of appropriate buffers around the nests. No project activity shall commence within the buffer area until a qualified biologist confirms that all young have fledged and the nest is no longer active. A buffer of 0.25 mile shall be implemented for Swainson’s hawk and white-tailed kite, and a buffer of 500 feet shall be implemented for other raptor species, (e.g., great horned owl, red-tailed hawk, red-shouldered hawk). Monitoring of the nest by a qualified biologist during and after construction activities will be required if the activity has potential to adversely affect the nest. The size of the buffer may be adjusted if a qualified biologist, in consultation with CDFW, determines that such an adjustment would not be likely to adversely affect the nest. The size of nest site buffer zones may be reduced only under the following conditions: A site-specific analysis prepared by a qualified biologist indicates that the nesting pair under consideration are not likely to be adversely affected by construction activities (e.g., the nest is located in an area where the hawks are habituated to human activity and noise levels comparable to anticipated construction work). The qualified biologist must submit this analysis to CDFW for review and approval before construction may begin within 0.25 mile of a nest. Monitoring by a qualified biologist is conducted for a sufficient time (during all construction activities for a minimum of 10 consecutive days following the initiation of construction), and the nesting pair does not exhibit adverse reactions to construction activities (e.g., changes in behavioral patterns, reactions to construction noise). Monitoring is continued at least once a week through the nesting cycle at that nest. This longer-term monitoring may be reduced to a minimum of 2 hours in the morning and 2 hours in the afternoon during Suisun-Solano Water Authority 2 New Cement Hill Pipeline Project IS/MND Ascent Environmental Proposed Mitigated Negative Declaration construction activities; however, additional and more frequent monitoring may be required if any adverse reactions are noted. If adverse effects are identified, construction activities shall cease immediately, and construction shall not be resumed until the qualified biologist, in consultation with CDFW, has determined that construction may continue under modified restrictions or that nesting activity is complete. Post-Construction-Start Occupied Nest Avoidance. If a nest tree becomes occupied by Swainson’s hawk, white-tailed kite, or other raptor species during ongoing construction activities, construction activities shall not occur within 500 feet of the nest, except where monitoring consistent with the criteria described above that adverse effects will not occur. Mitigation Measure 3.4-3: General Nesting Bird Avoidance and Buffers If ground- or vegetation-disturbing activities are scheduled to occur during the nesting bird season (between February 1 and September 1), a qualified biologist shall conduct visual pre-investigation surveys for nesting birds protected by the California Fish and Game Code in suitable habitat within 75 feet for non-raptor species. Surveys shall occur no less than 14 days and no more than 30 days before the beginning of construction for all project phases. The survey can occur at the same time as the survey described in Mitigation Measure 3.4-2. In the event an active bird nest (nests with eggs or young) is located during the pre-construction survey, a qualified biologist, in consultation with CDFW, shall establish a nest avoidance buffer zone (typically 75 feet). The qualified biologist can reduce the buffer zone based on a site- and nest-specific analysis. A qualified biologist shall monitor active nests to determine fledging status during construction activities. A qualified biologist shall also maintain the nest avoidance buffer zone during construction activities they determine nestlings have fledged and are no longer reliant on parental care for survival or the nest is abandoned. Mitigation Measure 3.4-4: Prevent Noxious Weed Spread Where it is not possible to keep equipment out of sites infested with noxious weeds, the equipment shall be cleaned so that it is free of soil, seeds, vegetative matter or other debris before being moved from infested sites to un-infested sites and before being transported out of the project area. Significance after Mitigation Mitigation Measure 3.4-1 would require protection of elderberry bushes so that they are not indirectly affected by project construction activities. Mitigation Measure 3.4-2 would require preconstruction nesting bird surveys and implementation of a buffer around active nests to avoid impacts to special-status bird nesting. Similarly, Mitigation Measure 3.4-3 would protect common nesting species. Operation would not result in additional impacts because maintenance activities would be similar to existing maintenance activities and would not require additional ground disturbance. Mitigation Measure 3.4-4 would prevent the spread of invasive species between separate parts of the project area. Impacts would be less than significant with mitigation incorporated.