ARCHIVED REPORTS_XR0012279 - Laserfiche WebLink

Home Browse Search

Prior to each phase of the aquifer pump test, the total gallons displayed on the flow meter/totalizer were recorded to determine the total number of gallons extracted during that phase The pump and data loggers AU 1 t the start of each phase of the pumpmg test The flow rate and data were turne on sim eons y a collected by the data logger was periodically monitored during the test Pumping duration for the constant rate discharge test was approximately 12 hours Once the constant rate pump test was completed, the pump was shut off and the recovery test began Prior to shutting off the pump, the data loggers were configured for the recovery portion of the aquifer test The exact time and the total gallons displayed on the flow meter/totalizer were recorded The pump was turned off and data logger stepped to collect recovery data The duration of the recovery test was determined by the data collected The recovery test was conducted for approximately 12 hours Extracted groundwater generated during the pumping test was temporarily stored on-site in a portable holding tank An effluent water sample was collected during the pumping test The analytical data could be used to design a groundwater remediation system Because groundwater was stored in a holding tank, appropriate samples were collected per disposal requirements The water was removed to an appropriate disposal facility by a licensed transporter The extracted groundwater was disposed of at Crosby and Overton, a State certified groundwater recycling facillLy located In Long Beach, California A copy of tree disposal manifest is included in Appendix C $,2 Aquifer Pump Test Results Beginning at 10 20 on December 19, 2002, a constant rate pump test was initiated at well EX -1 An asymptotic groundwater level was not observed in the pumping well Although the data retrieved from the transducer shows a pseudo -asymptotic level after approximately 8 5 hours, the drawdown depth actually exceeded the maximum capabilities of the transducer and it was unable to accurately report data at that time There were no problems encountered in retrieving data from the other three wells, so decisive conclusions__ can still be drawn from this pump test At 22 05, the pump was shut off and the recovery test began The well was allowed to recharge for approximately 12 hours Data collected during the constant rate discharge aquifer test was evaluated using various graphical and numerical methods, based on flow, which is assumed to be steady, well construction, which is partially penetrating, and aquifer type, which is unconfined Analysis of the aquifer test data was conducted utilizing AQTESOLV, a computer software designed and distributed by HydroSOLVE, Inc The Theis Solution for pumping in an unconfined aquifer was used to evaluate transmissivity, storativity and hydraulic conductivity of the aquifer Data requirements, including the pumping and observation well locations, pumping rates, observation well measurements of time and displacement, and aquifer saturated thickness, were collected and utilized for the Theis solution The least square fit Theis solutions for the four observation monitoring wells yielded transinissivities ranging from 0 016 square feet per minute (ft2/min) to 0 16 ft2/min, storativity ranging from 0 00078 to 1, and hydraulic conductivities ranging from 7 89E-5 EZ 100966 CAP S 1EZ Serve1EZ 1009661Reports1100966CAP 15 ATC Associates Inc ATC Project No 43 25827 0026