Case Study: Leaking Groundwater Monitor Well Casting
2006
Whitten, Charlie B. | Broughton, Jerald D.
Analysis of the chemical explosives data from up to six sampling events for wells 4-8 and 4-9 at Umatilla Army Depot, OR, show the concentration of explosives in each well have varied several orders of magnitude. Sampling crews had noted the purge water in well 4-8 changed color after the first well volume was removed. A field sampling program was conducted to collect samples from each well as the wells were purged. Point source bailer samples were taken at the top, middle, and bottom of the water column in each well before and after each well was purged. The point source bailer samples showed the explosive analytes concentrations decreased from the top to the bottom of the water columns with the pre-purge samples being up to an order of magnitude higher than the post-purge samples. The explosive analytes concentrations in the purge water dropped one to two orders of magnitude or below detection limit after one well volume was removed. The chemical data indicate that the explosive contaminants are leaking into the wells through the well casing at or near the top of the water column in each well.
显示更多 [+] 显示较少 [-]