ARCHIVED REPORTS_XR0005929 - Laserfiche WebLink

Home Browse Search

' �C Clayton LRO SESERVICES pack consisting of# 2116 sand was placed in the annular space from the bottom of the well at 25 feet bgs to approximately 4 feet bgs, roughly one foot above the top of the ' screen A bentonite seal, consisting of one foot of hydrated bentonite pellets, was placed to three feet bgs MW-1 was finished with a traffic-rated well box installed in concrete to approximately one inch above the surrounding surface Wells MW-2 and MW-3 were completed with aboveground monument casings to enhance visibility and protection As an added measure, crash posts were constructed around MW-2 and MW-3 ' Gregg Drilling & Testing, Inc , used a DV4 development ng to develop each of the three wells on January 17, 2003 Development consisted of surging each well followed by purging groundwater using a bailer and pump Each well was purged for approximately one hour with 93 gallons of water purged from MW-1, 113 gallons purged from MW-2, and 82 gallons purged from MW-3 In each well, the turbidity dropped to 0 by the end of purging Monitoring well development logs were included in Appendix D of the June 3, ' 2003 report ' 4.0 QUARTERLY MONITORING Following installation and well development activities, the wells were purged and ' sampled on a quarterly basis for one year Sampling was conducted on January 21, April 28, August 5, and November 13, 2003 The samples were submitted under chain of custody protocol to STL for analysis Each sample was analyzed for TPH-g, TPH-d, BTEX, and MTBE In addition,the samples from April 2003 were analyzed for tert- Butyl alcohol (TBA), Di-isopropyl Ether(DIPE), Ethyl tert-butyl ether (ETBE), tert- Amyl methyl ether (TAME), 1,2-DCA, and EDB Groundwater levels ranged from 6 63 to 12 07 feet bgs The corresponding groundwater elevations for these measurements are 2 32 and 4 01 feet below mean sea level Groundwater at the site flows to the southeast The hydraulic gradient was calculated as 0 0083, 0 0088, 0 0067, and 0 0051, respectively for the four monitored quarters ' The analytical results for groundwater samples indicated detections of TPH-d ranging from 64 µg/l to 620 µg11, as shown in the table below The laboratory flagged each of the ' diesel values as being a hydrocarbon that did not match the pattern of their diesel standard Toluene and xylene(s)were detected in the November 2003 groundwater sample from MW-2 at concentrations of 0 78 µg/l and 0 87 µg/l, respectively No other ' compounds were detected in the groundwater samples 1 ' 4 ' S 1ProkPO22631Project Surnrnary and Request for Closure doe