SFPUC 2001 Alameda Watershed Management Plan

III. ENVIRONMENTAL SETTING AND IMPACTSP. CUMULATIVE ANALYSISincreasing water demand and increase the reliability/redundancy of the SFPUC’stransmission system.Phase 1 includes improvements to the following treatment processes at the Sunol ValleyWTP: flow distribution/flash mix, flocculation, sedimentation, filtration, chemical feedsystems, residuals handling, plant drainage, electrical and instrumentation and controls,seismic upgrades, and functional upgrades. The SFPUC proposes to restore the SunolValley WTP’s capacity by installing plate settlers in the existing sedimentation basin. Allthe Phase 1 improvements are within the existing plant footprint and will be constructed bythe end of 2003. It is anticipated that Phase 1 will be found Categorically Exempt fromCEQA. A 40 million gallon treated water reservoir is proposed for construction at theSunol Valley WTP as soon as funds are available, which would be subject to CEQAenvironmental review.Phase 2 was developed based on demand projections from the Water Supply Master Plan.Based on a projected peak month demand of 440 million gallons per day (mgd) through theSunol Valley in 2010 and a restored Sunol Valley WTP capacity of 160 mgd, Phase 2recommends constructing a new 280 mgd direct filtration treatment plant at Alameda WestPortal. The project also includes a new pump station, transmission and distributionpipelines, and a 60 million gallon reservoir at the Alameda West Portal site. The newAlameda West Portal plant would be constructed in modules with the first module (240mgd) to come on line no sooner than 2010. Phase 2 would require CEQA environmentalreview.The impacts of this project would primarily stem from construction of facilities. Thisproject would not induce growth, since overall water supply system capacity would not beincreased. This project will be studied in a separate environmental review.2.2 NON-SFPUC PROJECTSMission Valley Rock and RMC Pacific Materials Mining Activities. Over 500 acres of theSunol Valley (nearly all within SFPUC-owned Watershed lands) have been permitted for miningby Surface Mining Permits (SMPs) from the County of Alameda. The mining operators, MissionValley Rock and RMC Pacific Materials, have lease agreements with SFPUC that permitsexercising of certain SMPs. The area covered under the mining permits described inSection III.B are in various stages of mining development. Mining activities in this area willcontinue, depending on various factors including market conditions, equipment operations,quality of mined product, and quarry characteristics. Under the Sunol Valley ResourcesManagement Element of the Management Plan, the preferred alternative would allow miningnorth of I-680 substantially pursuant to the SMP-32 EIR and mining permit; and south of I-680the project element calls for an increase in the depth of existing mining pits (sun2a and sun2b)and, potentially, a slight expansion of the footprints of these pits (sun2a) to match current miningpermit boundaries. Implementation of these management actions (sun2a and sun2b) would besubject to future Alameda County permit amendments.Mining north of I-680 would replace a portion of the current mining area south of I-680. The rateof ongoing mining south of I-680 is based on plant capacity and market demand. Mining south ofI-680 would continue in substantially the same location as existing mining and in an alreadyNOP 96.223E: Alameda Watershed Management Plan III.P-4 ESA / 930385January 2001