ARCHIVED REPORTS XR0006432 - Laserfiche WebLink

Home Browse Search

AM Working To Restore Nature • Subsequent to drilling activities, one 4 to 1 composite soil sample was collected from the stockpiled drill cuttings and analyzed for BTEX, TPHg, corrosivity, ignitability, reactivity, and lead, using appropriate laboratory methodologies. Petroleum hydrocarbon analytical results of soil samples are summarized in Table I Laboratory data sheets and chain-of-custody documentation are included in Attachment 3. Monitoring Well Construction Soil borings MW-4, MW-5, MW-6 and MW-7 were subsequently completed as groundwater monitoring wells to further assess the extent of groundwater contamination beneath the site, and to provide measurement points for the determination of groundwater flow direction and hydraulic gradient. The locations of the site monitoring wells are shown on Plate 2. Each well was constructed with 2-inch polyvinyl chloride (PVC) rasing. The screened interval of each well was positioned from approximately 5 feet above to 10 feet below the encountered water table to allow for seasonal water level fluctuations The screen slot size is 0.020-inch. Monitoring Well Development On August 1, 1994 the newly installed wells (MW-4 through MW-7) were monitored and developed in accordance with RESNA's Field Procedures included in Attachment 1 Field purge logs are included in Attachment 4. No hydrocarbon odors or other evidence of hydrocarbon contamination was noted during the development sf these wells, suggesting groundwater in the vicinity of the wells is not significantly impacted by petroleum hydrocarbons. Fluid bevel Measurements Fluid level measurements were collected from wells MW-1 through MW-7 on August 1, 1994. Levels were measured utilizing an electronic water/product interface probe capable of measuring with an accuracy of 11100 of a foot. No free product was detected Preliminary groundwater elevation data is summarized in Table 2. The newly installed monitoring wells (MW-4 through MW-7) were surveyed by RESNA personnel on August 1, 1994. This preliminary wellhead survey was conducted to provide wellhead elevations to evaluate the groundwater gradient beneath the Site Monitoring wells MW-1 through MW-7 were resurveyed on August 22, 1994 by a state-licensed surveyor. The respective wellheads were tied into a USGS benchmark at this time. The Generalized Site Plan will be updated and the calculated groundwater gradient will be presented in a site status report to be submitted for the third quarter of 1994 . 1230201ii-081594 WP