ARCHIVED REPORTS XR0007045 - Laserfiche WebLink

Home Browse Search

v � 0 • A S S O C I A T E S I N C A field geologist will be present to log all drill cuttings and soil samples Descriptions of soil types encountered and sample collection intervals will be recorded on boring logs Soil samples will be collected at five-foot intervals All sod samples will be field screened with a PID or similar instrument for VOCs Soil cuttings generated from drilling activities will be stored on-site in 55- gallon steel drums Well Construction Procedures Two-inch diameter, schedule 40 PVC casing and screen will be used to complete the groundwater monitoring well The proper lengths of clean screen will be threaded above ground prior to lowering inside the hollow stem augers The bottom of the screen interval will be fitted with an end plug and the top of the casing will be fitted with an expandable, watertight, locking cap It is anticipated the well screen length will extend from a depth of 10 to 30 feet bgs No glue will be used in the assembly of the groundwater monitoring well The annular space between the well screen and the sidewall of the borehole will be filled with clean No 2/16 sand or equivalent to provide filtration capacity and impede movement of fine particles into the well The sandpack will extend 2 feet above the top of the well screen A 2-foot thick interval of hydrated bentonite will be placed above the sandpack and the remaining annular space will be backfilled with a neat cement grout containing 5% powdered bentonite The monitoring well will be finished with a watertight security traffic box to protect from vandalism or entry of surface fluids Typical monitoring well construction details are shown on Figure 3 Soil Sample Analysis At least two soil samples collected from the boring will be placed on ice and sent using chain-of- custody record to a State-certified laboratory for analysis Selected soil samples will be analyzed for TPHg and TPHd by EPA method 8015K benzene, toluene, ethyl benzene, and xylenes (BTEX) by EPA method 8020, and for oxygenate fuel additives including MTBE by EPA Method 8260 Well Develo ment The new well will be developed using surge and bail techniques until the produced water is relatively sediment free After well development, the relative elevation of the monitoring well (i e top of casings) will be surveyed and tied into the existing groundwater monitoring wells All survey elevations will be measured to an accuracy of 0 01 feet Monitorinz Well Sampling and Anal tic 1 Procedures Groundwater sampling of all on-site wells will be performed after the new well is developed Prior to purging, the water levels in the wells will be measured using an electronic probe to an w 162514Vgxwblwkp dw 4