SU0004094 - Laserfiche WebLink

Home Browse Search

6. OTHER STATUTORY CONSIDERATIONS instability condition,if one did exist. The project would attract additional workers to the mining _ and could place additional people in harms way during an earthquake. The project,therefore, could be responsible for contributing to a cumulative seismic risk impact as other proposed and existing projects in the region attract workers into the area. However,the number of workers — added to a region from the proposed RMC project and other mining projects in this undeveloped area is negligible when considering the overall population that would be exposed to potential harm from a large regional earthquake. Because of this,the cumulative contribution is less-than- significant. HYDROLOGYAND WATER QUALITY — Groundwater Consumption The cumulative impact analysis for hydrology and water quality considers the region surrounding the Proposed Project site(including the city of Tracy)that currently or in the future, may extract groundwater from the extensive confined groundwater aquifer in the lower Tulare Formation(see — Hydrology and Water Quality, Section 4.8). Compared to the groundwater in the shallow, unconfined aquifers and the semi-confined aquifers within the upper Tulare Formation, the lower Tulare provides groundwater at a substantially greater quantity and with higher quality. The lower Tulare Formation provides groundwater supply for industrial uses(namely active mining operations) near the Proposed Project area and municipal and industrial uses within and — surrounding the city of Tracy. This analysis assumes that existing industrial operations and municipal groundwater demands would remain essentially the same while Proposed Projects within the region would pump groundwater either as their primary supply or to supplement a — surface water supply. As mining operations typically demand a substantial water supply for processing,dust suppression, landscaping, and domestic use,the use of groundwater for the Proposed Project,in combination with other mining projects in the area,could cumulatively — affect groundwater supply within the lower Tulare Formation. The cumulative affect would likely be realized in the gradual decline of water levels in the lower Tulare Formation as proposed municipal and industrial projects are developed in the future. A gradual decline in groundwater — elevations caused by a cumulative increase in groundwater use could eventually reduce the capability of some users to extract groundwater. Excessive cumulative groundwater extraction can also lead to aquifer overdraft and subsidence,as was experienced in some areas of the San — Joaquin Valley during the height of agricultural groundwater use in the mid-1900s. The construction of the Delta-Mendota Canal and California Aqueduct helped reduce groundwater use and arrest further subsidence in the affected regions. As discussed in the Hydrology and Water Quality chapter,Section 4.8, subsidence has not affected the region surrounding the Proposed Project site or the Tracy area. — Dependence on groundwater is typically reduced by increased availability and use of higher quality imported surface water supplies,reduced agricultural groundwater pumping, water — conservation, and efficient agricultural irrigation practices. Raised awareness of potential groundwater depletion has encouraged groundwater studies designed to determine the sustainable aquifer yields and avoid adverse impacts to underlying aquifers. Throughout the San Joaquin — RMC Pacific Vernalis Quany Mining and Reclamation Project 6-12 FSA/201015 Adotinist auve Dtaa Eat Match 2004