ARCHIVED REPORTS XR0001918 - Laserfiche WebLink

Home Browse Search

l l 1 C ' m- _c t S_ _ r � -• x{ _ y ' - - . n I � —z_ i I _ — x � — — ? '6� e, 1 I 12 February 2002 AGE-NC Project No 97-0312 Page,12 of 18 - „A 1 i � For Inspection purposes, the EHD will be notified at least 48 hours prior to conducting grouting procedures A traffic-rated well box will be Installed over the monitoring well Following completion of the monitoring wells, well elevations and locations will be surveyed by a California-licensed surveyor it t h 4 4 2 Ground Water Extraction Well Installation a ' One pilot boring will be advanced for the Installation of a ground water extraction well The boring will be advanced with a truck-mounted drill rig equipped with 10-inch hollow-stem augers Following advancment of the pilot boring,4-mch diameter Schedule 40 PVC 0 010-'mch slotted well ' .screen and casing will be installed A 20-foot section of screen will be utilized for the well, from t approximately 55 feet bsg to 75 feet bsg The well 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#2/12 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 In settling the filter pack Additional sand will be added If settling occurs I A nominal four-foot thick bentonite seal will be placed above the filter pack to minimize the potential of grout penetration Into the filter pack or screened section of the well The bentonite seal will be formed by pouring bentonite chips Into the annulus and allowing them to settle on the filter pack Bentonite chips will be hydrated using five gallons of water The bentonite chips will be allowed to hydrate for a minimum of one-half hour prior to grouting The remaining annular space will be filled to within one foot of the ground surface with a cement grout The grout mixture will consist of type I/II portland neat cement and not more than 6 gallons " of water per 94-pound sack of cement The grout will be placed by pumping through,a tremmle pipe For Inspection purposes, the EHD will be notified at least 48 hours prior to conducting grouting ' Cprocedures A traffic-rated well box will be Installed over the monitoring well ` { 4 4 3 SVE Well Installation r " Following advancment of each pilot boring, a 2-inch diameter Schedule 40 PVC 0 010-Inch slotted well screen,and casing will be Installed A 15-foot section of well screen will be utilized for each well, from approximately 10 feet bsg to 251 feet bsg The well 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#2/12 Lonestar sand will be added from the bottom of the borehole to approximately two feet above the screened interval Advanced GeoEnvironmental,Inc i