ARCHIVED REPORTS_XR0012631 - Laserfiche WebLink

Home Browse Search

s 1s$y1.� r^� Mr. Hal Miller F 4 June 8, 1989 JUN 1 9 1989 Page 4 [nn��r,^;,•fav"_'�t`r.ALL.:� _i FR from PW-1, PW-3, MW-4 and MW-12. Falling water levels resulted in reduced pumping rates ranging from 0.125 to .5 gpm per well. Some free product recovery continued from MW-4. Monitoring and domestic well sampling continued on a regular schedule through 1987. Domestic well sampling results showed sporadic non-confirmable dissolved hydrocarbons in samples an several occasions through the year. Detectable concentrations could not be repeated from sampling event to sampling event. The lateral extent of the dissolved hydrocarbon plume remained undefined in early 1987 extending off-site in all directions. The lateral extent of the dissolved plume began to shrink in late 1987 as water levels dropped due to regional drought conditions. By late December, 1987, the dissolved plume extent had receded and was primarily contained on site. 1988 Continued falling water levels (See Attached Figure 2 and Table 3) resulted in reduced pumping capacity from PW-3 and all other pumping wells. Pumping from MW-4 and MW-12 was discontinued. in an effort to gain better hydraulic control on eneath the site, a new, deeper recovery the groundwater flowing b well (RW-1) was installed on site in February 1988. Recovery well RW-1 was initially pumped at a rate of 5 gpm giving a calculated dawn gradient ^apture radius of loo-feet. However, pumping .o-f the new deeper recovery well confirmed that the hydrogeology beneath the site is laterally discontinuous. Pumping in RW-1 failed to influence free product found in MW-^4 and high dissolved concentrations found in 181-1. it was interpreted that the recovery well was getting production £rnm a deeper, more transmissive zone that is not in communication with the upper zone beneath the site. TEcim(}LOGY,INC.