A tale of two Long Island plumes

It was dismaying enough to learn that a plume of groundwater contamination from an old Northrop Grumman-U.S. Navy testing facility in Calverton has spread farther than previously understood. But new revelations that Grumman knew at least 35 years ago that its hazardous waste could leak and form a toxic plume with a path straight to the Peconic River provokes real anger and a sense of foreboding:

Here we go again.

The echoes of Bethpage, where a larger Grumman-Navy manufacturing facility was the source of a horrendous plume that’s been expanding for decades, are unmistakable. In that debacle, decades of denying, downplaying, stonewalling, and deceit chronicled by Newsday allowed the plume to expand to its current size of 4.3 miles long and 2.1 miles wide and imperil local water supplies.

In Calverton, it’s déjà vu. Newsday reporters discovered that a judge in a 2013 case found that Grumman knew in 1986 that its hazardous waste disposal sites could leak solvents and jet fuel into groundwater and referred to Grumman’s hear-no-evil, see-no-evil response as an "Ostrich defense." Now the Navy, which is handling cleanup at the site Grumman left in 1996, is refusing to test beyond a 1-mile radius despite flow calculations showing the contamination likely has spread beyond that to some of the 60 to 125 homes in the area with private wells. Already, Navy testing at the property’s perimeter found high concentrations of possible carcinogenic chemicals known as per- and polyfluoroalkyl substances. Suffolk County testing of private wells found at least one with a concentration nearly 10 times the state limit.

The Navy’s recalcitrance is distressing given the recent Grumman-Navy agreement to execute and nearly fully fund a $406 million plan to contain and clean up the plume in Bethpage. The long-overdue deal, reached after pressure from federal, state and local officials overcame institutional intransigence, is worth celebrating. The 30-year plan, largely the same as one proposed by the state Department of Environmental Conservation, will install a series of containment wells to extract contaminants within and along the edges of the plume. The DEC must make sure Grumman and the Navy follow through on their commitment, especially if more containment wells are needed to stop the plume’s one-foot-a-day march toward the Great South Bay. Grumman’s pledge to pay $104 million in environmental damages was a significant concession from a company that has fought requests to compensate water suppliers for their cleanup costs.

But it’s also worth noting the cautionary-tale element here: Everyone is finally on the same page and working toward the same goal only after endless delaying made the plume much more difficult and costly to treat.

The Navy needs to take that lesson to heart. It should expand its testing in Calverton, use the state’s tough limits on pollutants as its baseline, start the cleanup, and pay to connect private-well owners to public water. It took decades before anyone could expect that the threat in Bethpage would begin to diminish. Long Island can’t wait that long for the same result in Calverton.

— The editorial board