Post date: Sep 01, 2014 4:33:52 AM
October 14, 2001
Plume Definition and Capture Still Lacking
An analysis of sampling data made public by Pall-Gelman (now Pall Life Sciences) shows that of the 187 monitoring locations, 72 had their highest readings ever during the last year (September 2000 through August 2001).
Many (26) of these monitoring wells were new wells in that time period, signifying newly discovered 1,4-dioxane locations and lack of full delineation of the 1,4-dioxane plumes.
Several others had not been sampled for over a year and up to five years. Highest ever readings on these wells show the continuing spread of the 1,4-dioxane plumes while no one was looking.
E Aquifer Contamination
A half dozen new monitoring wells have been installed in the E aquifer. Sampling from these wells range from non-detect (< 1 ppb) to 3250 ppb. The 3250 ppb was at MW-64 up from the initial reading of 841 ppb on 5/30/01.
Increased Purging
In an attempt to reach the court-mandated cleanup levels by July, 2005, Pall has installed more purge wells and is adding another system to partially destroy the 1,4-dioxane. Pall Life Science maintains that these actions will require the dumping of partially treated purge water into the Honey Creek tributary above the current permitted rate of 800 gallons per minute (1,152,000 gallons per day). Pall is demanding that the DEQ raise the limit to 1300 gallons per minute.
SRSW advocates the use of a hybrid approach in which the 1,4-dioxane is fully destroyed and some of the purge water is re-injected back into the aquifers in a controlled way to "flush out" the remaining contamination. Any increased volume discharged into the tributary should be at proportionally lower concentrations to minimize the risk to water supplies downstream.