ARCHIVED REPORTS XR0001691 - Laserfiche WebLink

Home Browse Search

J ' 14 September 2001 • AGE-NC Project No 95-0109 ' Page 7 of 9 Proposed soil boring locations are illustrated on Figure 1 Following borehole advancement,portland ' cement(grout mix)will be utilized to backfill each borehole utilizing a trerrue pipe The PHS-EHD will be notified 48 hours prior to initiation of field activities to schedule a grout inspection prior to backfilling the borings 43 SOIL SAMPLING The proposed monitoring well boring will be completed using hollow-stem auger drilling techniques Relatively undisturbed soil samples will be collected at five-foot intervals beggining at 5 feet bsg and extending to the total depth of the boring utilizing a California modified split-spoon sampler ' fitted with 2-inch diameter, 6-inch long brass sleeves Upon removal from the sampler,the exposed ends of a selected sleeve will be covered with Teflon sheets, capped and sealed with tape Soils encountered in the bonngs will be visually classified by an AGE geologist in accordance with the Unified Soil Classification System(USCS) Additionally,soil samples will be field-screened for the ' presence of volatile organic compounds using an organic vapor meter(OVM) Soil cuttings will be ` containerized in properly labeled DOT-approved model 17H 55-gallon drums and stored on-site Disposal alternatives will be evaluated at a later date based on laboratory results of the soil samples Following sample collection,each preserved sample sleeve will be labeled with the boring location, depth, time, date and sampler's initials Appropriately sealed and labeled samples will be placed in a chilled container under ice and transported under chain-of-custody to a DHS-certified laboratory A total of five soil samples will be submitted for analysis 4 4 MONITORING WELL INSTALLATION ' Following completion of drilling the boring, a 2-inch diameter Schedule 40 PVC 0 020-inch slotted well screen and casing will be installed A 20-foot section of well screen will be installed in the boring, extending approximately 15 feet below and 5 feet above the top of the ground water table An air tight locking well cap will be placed on the top of each well casing The well casing,filter pack and sealing materials will be placed into the borehole through the interior of the hollow-stem augers After installing the well casing, filter pack material consisting of pre-washed#3112 Lonestar sand will be added from the bottom of the borehole to approximately two feet above the screened interval Following placement of the filter pack, the well will be surged to assist settling the filter pack Additional sand will be added if settling occurs A nominal two-foot thick'bentomte seal will be placed above the filter pack to minimize grout • penetration into the screened section of the well The bentonite seal will be formed by pouring Ibentonite chips into the annular space between the auger and the well casing and allowing the chips Advanced GeuEnvironmental,Inc y