ARCHIVED REPORTS_XR0008438 - Laserfiche WebLink

Home Browse Search

' 25 February 2005 AGE-NC Project No 95-0104 ' Page 8 of 10 ' boring logs Upon soil sample retrieval, the middle brass sleeve will be removed from the sampler The ends of the brass sleeve will be immediately covered with Teflon or aluminum sheets, sealed with plastic end caps, secured with tape and immediately placed in a chilled container for ' transportation under chain of custody to a state-certified laboratory Each sample sleeve will be labeled with the boring location, sample depth, sample time, sampling date and sampler's initials ' During sampling activities, sample duplicates will be monitored for the presence of organic vapor using a photo-ionization detector (PID Thermo Environmental 580, 10 0 eV, calibrated to ' isobutylene) and will be visually described on boring logs using the Unified Soil Classification System (USCS) ' All sampling tools and brass sleeves used for sample collection will be thoroughly rinsed with clean water after washing with a solution of Alconox All hollow stem augers will be steam-cleaned prior to advancement in each borehole 1 43 WELL COMPLETION The soil boring will be single-completed as ground water monitoring wells utilizing 2-inch diameter ' schedule 40 polyvinylchloride (PVC) 0 020-inch slotted well screen and blank well casing Based on geologic/hydrogeologic conditions, a 20-foot length of well screen is anticipated for installation of the shallow monitoring wells, and a 5-foot length of well screen is anticipated for the installation ' of the deep monitoring well The screens will be placed from 65 feet to 85 feet and from 95 feet tol00 feet bsg Proposed well construction diagrams are depicted in Figures 10 and 11 After installing the well casing, filter pack material consisting of pre-washed#3 Lonestar sand will be added through the screen interval 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 A nominal two-foot bentonite seal (bentonite pellets) will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the well The bentonite seal will be formed by pouring either bentonite chips or pellets into the annulus and allowing them to settle on the filter pack Bentonite pellets will be hydrated using approximately five gallons of tap water The bentonite will be allowed to hydrate for a minimum of one-half hour prior to grouting The remaining annular space will be filled to 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 tremmie pipe A grouting Advanced GcoEnvironmental,Inc I