ARCHIVED REPORTS_XR0007947 - Laserfiche WebLink

Home Browse Search

i 19 January 1998 AGE-NC Project No 96-0229 Page 3 of 8 2 3 GROUND WATER MONITORING WELL INSTALLATION 1 Soil borings MW1 through MW6 were completed as ground water monitoring wells by utilizing 2- inch diameter, schedule 40, blank polyvinylcholoride (PVC) casing and 2-inch diameter screened PVC casing (0 020-inch slot) Each well was installed by placing the PVC well casing assembly through the hollow stem of the augers to the total depth of the boring The augers were incrementally raised as 43 Lonestar Lapis Luster sand (filter pack) was slowly poured down the annulus between the well casing and the Inner wall of the hollow stem auger The filter pack was placed adjacent to the screened casing from the bottom of the boring to a point approximately two feet above the top ' of the screen Following placement of the filter pack, a surge block was inserted into the PVC casing and was lowered then raised (surged) repeatedly for approximately 10 minutes Thereafter, a minimum of three feet of bentonite coded pellets (pell plug) was placed above the filter pack and ' hydrated with clean tap water to serve as an annular seal The remaining annular space was sealed with portland type II cement As-built well construction diagrams are included as Figure Nos 5 through 10 - Well Construction Diagrams 2 3 1 SURVEYING December 1997, a California state-licensed survey engineer from Baumbach & Piazza Inc On 18 surveyed a reference point on the top of each ground water monitoring well at the site to the nearest ' 0 01-foot relative to the City of Stockton Bench Mark Datum # 15 The results of the monitoring well survey are contained in Table 2 - Relative Ground Water Elevations The surveying report (Baumbach & Piazza Job No 9797) is presented in Appendix B ' 2 3 2 WELL DEVELOPMENT Monitoring wells MW I through MW6 were developed utilizing a two-stage submersible pump ' Ground water was purged from each screened well until the water produced was essentially sediment free Approximately 25 gallons of ground water were purged from each screened interval Purged ground water was containerized In properly labeled D O T -approved model 17H 55-gallon drums and was stored on-site in an area lacking public access 2 4 QUARTERLY MONITORING AND SAMPLING ACTIVITIES On 24 November 1997, quarterly ground water monitoring and sampling were performed on monitoring wells MW 1 through MW6 Depths to ground water and total well depths at MW 1 through MW6 were measured to the nearest 0 01-foot utilizing a Solinst water level meter The Advanced CcoEmironmcntal,Inc