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5.Alternatives may not be considered the environmentally superior alternative because additional land would — need to be disturbed elsewhere to obtain aggregate resource sooner than with the project. Alternative 2—Scenario 1 would result in similar impacts as the project, but to a lesser extent due to the decrease in the amount of material to be mined on a yearly basis. Transportation and circulation impacts and noise impacts would be less than the project due to a decrease in the amount of traffic on a daily basis over the life of the project. However,the significant and unavoidable impacts associated with the project would not be reduced with this alternative. Alternative 3—Off-site Alternative would result in similar impacts as the project, some to a lesser — extent and others to a greater extent than the project. With this alternative site being located closer to the market in Tracy, the traffic impacts could be reduced due to the shorter distance traveled to market areas. However,there are a greater number of residences near the off-site — alternative so the impacts to sensitive receptors associated with noise and air quality from the mining and aggregate processing would be increased over those of the project. 5.4 Alternatives Considered But Rejected as Infeasible An off-site alternative in the Laguna Formation of the foothills was considered for inclusion in this EIR in order to eliminate the significant and unavoidable impact to farmland by finding a site outside the Central Valley that would not include prime farmland,farmland of statewide — importance, and Williamson Act contract land. This off-site alternative was rejected because of the lack of an adequate aggregate resource to — meet the sponsor's basic objectives. Many resource sectors in the Laguna Formation of the foothills were not controlled by an aggregate company or encroached upon by competing land use as of 1988' (CGS, 1988). However, since 1988, many of these sectors have been developed as a — result of growth in the Bay area, thus making any underlying resource unavailable for mining and/or extraction. Some new developments in the area include New Jerusalem and the Diablo Valley(Don Depraw, CGS). — The Laguna Formation is one of several alluvial rock units found directly west of the Sierra foothills. Sediments of the Laguna Formation are derived from weathering and erosion of — resistant bedrock units in the foothills. The Laguna Formation is an unsuitable material for PCC- grade aggregate due to several constraints,described below. First, since the Laguna Formation is _ Pliocene in age, it is significantly older than most material in the area that meets aggregate standards.Due to its age, significant weathering rinds, or fine-grained brittle outer casings,are present on gravel clasts. During mining, the brittle casing commonly becomes dislodged from the — gravel,adding unwanted fine-grained material to the aggregate mixture. The formation itself is not easily crushable,but largely cemented, making extraction and processing difficult. Second, since the Laguna Formation is derived from the Sierra Nevada, volcanic clasts in its matrix cause — mining and processing difficulties. Third,due to significant clay content in the Laguna 1 CGS Special Report 160,Mineral Land Classification:Portland Cement Concrete Aggregate in the Stockton-Lodi — P-C Region(San Joaquin County,California)is the most recent report which assesses the resource sectors in the proposed project area.It was published in 1988. RMC Pacific Vemalis Quarry Mining and Reclamation Project 5-20 ESA 1203015 — Draft Environmental Impact Report May 2006