By Tony Burchyns Staff Writer
Morgan Hill – A 100-page report that addresses the long-term cleanup efforts of Olin Corp., suggests a passive monitoring program that would be carried out over a 20 years to the tune of $5.6 million. However, the report on the 9.5-mile perchlorate plume stretching south from Tennant Avenue in Morgan Hill to north of Gilroy, defers until August a cleanup solution on the area immediately south of the company’s former Tennant Avenue factory.Â
The company also explored – but rejected – a more aggressive and thorough cleanup strategy in the report, which would cost $250 million and would have reduced perchlorate levels in the South County water table to 4 parts per billion (ppb).
Tom Mohr, a geologist with the Santa Clara Valley Water District, said he understands some people may criticize Olin, but he thinks the proposed measures are reasonable at face value.Â
“When you get into money like $250 million, even if from a corporation, you have to weigh the societal cost of that,” said Mohr.
The report was submitted to the Central Coast Regional Water Control Board June 30. The board may make revisions to the document.
Rick McClure, who oversees the South County cleanup effort for Olin Corp., was on vacation when contacted and declined to comment. His signature, however, appears in the report’s cover letter.
Hector Hernandez, the water board engineer on the case, is also on vacation this week.
As for parts of the cleanup report that were deferred until August, the reason for the delay is so Olin’s consultants can further study the water table surrounding the site.Â
To that point, consulting engineers at a June 29 Perchlorate Community Advisory Committee meeting said they had not yet characterized the depth of the deepest aquifers beneath the site.