ARCHIVED REPORTS XR0012541 - Laserfiche WebLink

Home Browse Search

F 4 � I ?7= All MOMMEMN Fg K� 'r, all ri-11' W{ 5 . 0 PROPOSED MONITORING PLAN I . To determine whether the excavation of the contaminated area sufficiently removed the contamination, a soil boring is proposed directly to the northeast of the excavation area, rather than within the excavation area because the compacted backfill would hinder the boring operation. This proposed • location is downgradient of the excavation area assuming the it general northeasterly ground water flow direction for the } , region exists at the site. The boring will be accomplished by i using a hbllow stem auger, and split spoon soil sampling will be performed at 5 ft intervals from a depth of 15 ft to 40 ft L'=M i , (or to the depth at which ground water is encountered, whichever occurs first) . An onsite geologist will visually !" inspect the drill cuttings and split spoon samples during the E ° boringoperation to p prepare a geologic log of the soil boring. f ' The geological log of the soil boring will be prepared in an attempt to identify the presence of zny impermeable strata � £ which may cause lateral movement of any contamination. The soil samples will be checked by using a photoionization detector (PID) . Should the soil samples show no positive Ir � . readings, and if no indication of lateral contaminant migration is suspected due_ to the site specific geology, the ! ' hole will be filled to the surface with the drill cuttings. jtv The boring results will then be reported to the San Joaquin i ° APCD and California Water Quality Control Board (WQCB). I > However, if the soil sai-i_ les show positive PID readings, the soil samples will sent to a California certified laboratory for analysis for extractable and volatile hydrocarbons. The soil boring will be completed into a monitor well ( see Figure 5--1 for well construction details) , and an additional two or F to { a , I