DTSC has approved a Response Plan for the Fred C. Nelles Youth Correctional Facility.
The RP, incorporated herein by reference, consists of removal activities to address elevated concentrations of mainly arsenic, lead, and organochlorine pesticides (OCPs) in the soil.
The selected alternative in the RP includes the excavation and on-site consolidation of approx. 48,000 cubic yards of lead, arsenic, and OCP impacted soils. Approx. 400 cubic yards of lead-impacted soils, anticipated to be RCRA-hazardous waste, would be excavated and transported off-site for disposal.
The selected remedy in the RP includes the excavation of lead, arsenic, and OCP impacted soils around the buildings and arsenic impacted soils in the open areas of the Site (i.e. former agricultural area, railroad easement, playing fields). The excavated material will be replaced with non-impacted soil from other areas of the Site as required by the Site grading plan.
The removed impacted soils from the residential area of the Site will be consolidated in the commercial area, and capped by non-impacted soils and hardscape to minimize exposure to consolidated materials and possible migration to groundwater from infiltration rainwater.
Soil removal will be accomplished using conventional grading equipment and standard dust suppression, stockpiling, and stormwater best management practices would be incorporated into the soil removal activities.
In most areas, excavation will be required to 1 to 2 feet below ground surface (bgs); however, in isolated areas, excavation will be 18 bgs. The total volume of impacted soils that exceed remedial goals is estimated to be approx. 48,800 cubic yards. Of this volume, approx. 400 cubic yards of lead-impacted soils, anticipated to be RCRA-hazardous waste, would be excavated and transported off-site to a permitted disposal facility.
It is anticipated that excavations can be accomplished using open cut methods. If open cut methods are locally infeasible, excavations can be accomplished using limited excavation support systems, such as soldier-piles and lagging or trench boxes. The excavation will not extend below the groundwater table; therefore, temporary dewatering and associated groundwater disposal will not be required as part of the work. Surface water runoff will be handled in accordance with the Construction General Permit.