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Setbacks, Slopes and Depth Temporary slopes, other than along Blewett Road, Koster Road, and South Costa Ranch Road would be mined to a 3/4:1 slope. The mining areas along Blewett Road, Koster Road, and South Costa Ranch Road and next to Hospital Creek would be mined to a 2:1 slope for slope protection near the Delta Mendota Canal and Hospital Creek and the two perimeter roads.Within two years after mining has been completed within a phase, the slope will be backfilled to 2:1 using overburden and interbedded clays. San Joaquin County Surface Mining Ordinance 9-1415.3k requires final slopes over 50 feet in vertical distance to have terraces and terrace drainage. Minimum final slopes may be 1 1/2:1. The applicant originally requested building final slopes with over 50 feet in vertical distance without terracing. However, the applicant has withdrawn the request to delete terracing. It is proposed that all existing topsoil would be stockpiled and reused in final reclamation, with a waste shrinkage factor of 10 percent. This would result in 800,000 cubic yards of topsoil available, which would equate to 6 to 9 inches in depth of topsoil over all final slopes and pit bottom. The slopes would be hydroseeded with an appropriate seed mix for erosion control at a time that would maximize vegetation growth for erosion protection. Hospital Creek Hospital Creek borders the southern boundary of the site and crosses the southwest corner of the site after passing over the Delta-Mendota Canal in a box culvert. Two options were proposed for mining near Hospital Creek, as follows: • Mining Plan Option 1: Leave Hospital Creek in place, mining both sides with a 100-foot setback from the centerline of the creek to the top of the mining slope. Refer to Figure 3-3 (Mining Plan Option 1). • Mining Plan Option 2: A 100-foot high berm would be constructed out of both on-site and off- site materials along the line between the Phase III and Phase V areas and between the Phase VI and Phase VII areas. Refer to Figure 3-4 (Mining Plan Option 2). This would create a large retention basin. The inlet and outlet would be modified to become a spillway and an overflow. Hospital Creek would then be mined out within the project boundaries and the creek would flow directly into the large retention basin through a concrete spillway. Mining Option 2 has been dropped from the proposal. The staff report will only analyze Mining Option 1. Public Safety The Applicant proposes to implement measures to prevent accidental and unauthorized access to the mining areas. The Applicant would install and maintain fencing, consistent with the San Joaquin County Code, and warning and no-trespassing signs around the perimeter of the property. Gates would be installed and roving security patrols would be employed during non-operational hours. Signs would be installed for regular traffic and delivery routes and lighting would be installed and maintained for traffic and safety purposes. Haul roads would be graded, watered, and maintained with berms for traffic safety. Slopes would be fenced to prevent public access and replaced at 2:1 per County Code requirements. Equipment, roads, fences, and security would be maintained in compliance with County Code, Mine Safety and Health Administration (MSHA) regulations, and Cal-OSHA regulations. San Joaquin County QX-01-2\Lonestar California Community Development Page 9