WORK PLANS FILE 1 - Laserfiche WebLink

Home Browse Search

i Report:Work P an for Groundwater Monitoring Date: February 13,2004 ATTACHMENT B SAMPLING AND ANALYSIS PROCEDURES Exploratory Drilling and Soil Sampling The soil borings will be drilled using 8.25 and 10.25-inch hollow-stem auger drilling equipment. Borings will be logged by a URS geologist using the Unified Soil Classification System. Soil samples will be collected from the borings at 5-foot intervals and/or continuously using a California modified split spoon sampler. The sampler will be driven a maximum of 18 inches using a 140-pound hammer with a 30-inch drop. Soil samples for chemical analysis will be retained in brass liners, capped with Teflon®squares and plastic end caps,and sealed in clean zip-lock bags. The samples will then be placed on ice for transport to the laboratory accompanied by chain-of-custody documentation. Down-hole drilling and sampling equipment will be steam-cleaned following the completion of each soil boring. Down-hole sampling equipment will be washed in a non-phosphate soap and deionized water solution between samples. Groundwater Monitoring Well Installation The groundwater monitoring well will be constructed of 2-inch inside diameter schedule 40 PVC blank casing and 0.020-inch machine slotted well screen with flush threads. A#3 silica sand filter pack will be installed in the annulus from the bottom of the borehole to at least 3 feet above the top of the well screen, followed by a transition seal consisting of a 3-foot-thick hydrated bentonite plug, which in turn will be overlain by neat cement grout to ground surface. The well will be secured with a locking expandable well cap and fitted with a traffic-rated well box set in concrete. The groundwater remediation wells will be constructed of 2 and 4-inch inside diameter schedule 40 PVC blank casing and 0.020-inch machine slotted well screen with flush threads. A#3 silica sand filter pack will be installed in the annulus from the bottom of the borehole to at least 3 feet above the top of the well screen, followed by a transition seal consisting of a 3-foot-thick hydrated bentonite plug, which in turn will be overlain by neat cement grout to ground surface. The wells will be plumbed to the proposed site remediation system and fitted with traffic- rated vault boxes set in concrete. Soil Sampling from Drummed Soil Soil samples are collected by advancing 2-inch-diameter brass sample liners into the soil drum, after removing approximately 6 inches to 1 foot of surface material in the sample location. One composite will be collected from each drum. Soil samples for chemical analysis are retained in the brass liners, labeled, and capped with Teflon® sheets and plastic end caps. The samples are then sealed in zip-lock bags, placed on ice, and transported to the laboratory accompanied by the appropriate chain-of-custody documentation. Laboratory Analysis of Soil Samples Soil samples are analyzed for TPHg, BTEX, fuel oxygenates, and lead scavengers by EPA Method 8260B. Drummed soil samples are analyzed for TPHg and BTEX by EPA Methods 801518021; lead content is analyzed by EPA 6000/7000 Series Methods. KAWprocessV5 BP ARC010218612186 Workplan 04.doc Page B-1