More Work Needed To Trace Plume

The perchlorate plume swishing through South County’s water
table has already taken years to locate and characterize, but
there’s still more work to be done to uncover all of its obscure
movements at various depths and latitudes, according to state water
officials and Olin Corporation engineers.
 
By Tony Burchyns Staff Writer

Morgan Hill – The perchlorate plume swishing through South County’s water table has already taken years to locate and characterize, but there’s still more work to be done to uncover all of its obscure movements at various depths and latitudes, according to state water officials and Olin Corporation engineers. 

In a June 29 letter of response to Olin Corp.’s March 2006 “characterization report,” the California Regional Water Quality Control Board agreed with Olin’s engineering firm, that more data is needed to trace the lateral extent of perchlorate in the intermediate and deep aquifers to the south and to the west of the Tennant Avenue road flare factory that is believed to be the source of the contamination. 

Nevertheless, the water quality control board is not requiring Olin Corp. to further update its recent perchlorate report though water officials say several statements in the report concerning the possibility of other sources of perchlorate are made without any analytical data. 

In its response, the water board remains firm that Olin is the responsible source of the perchlorate detections in ground water impacted by the Olin site. 

Hector Hernandez, the regional water board engineer overseeing the cleanup, said concerns will be addressed in future reports. 

The latest report preceded Olin’s recent cleanup feasibility study, which was submitted June 30. The document is more than 100 pages long, and defers until August any cleanup solution for the area directly surrounding the former Tennant Avenue factory.