The Chester River Hospital told the Town Council on Monday that oxygen injections in the ground at the Brown Street parking lot last year were not responsible for iron bacteria contamination of a well that supplies drinking water to the town.

The oxygen injections were an attempt to clean up the remains of an underground heating oil spill of nearly 100,000 gallons in 1988.

Since then, the hospital has been involved in a costly cleanup effort that has reached over $1 million to date—and the oil recovery efforts are now yielding considerably less heating oil—leading the hospital’s cleanup contractor, Earth Data, to conclude that there is very little oil left to recover.

“We’ve recovered over 83,000 gallons at this point,” said Andrew Bullen of Earth Data.

The hospital received permission last year from MDE to perform the oxygen injections in an attempt to accelerate the growth of naturally occurring bacteria in the ground—to help remove any remaining heating oil, said Bullen.

But the hospital and MDE did not notify the town—a major point of contention with Chestertown Utilities Manager Bob Sipes, who said the timing of the oxygen injections, and the malfunction of Well #9, drew suspicion from a repair contractor, who said the oxygen injections may have started the buildup of iron bacteria in the well’s pump—causing it to seize.

Sipes reiterated that he never accused the hospital of contaminating the well and that the timing was only “suspicious.” He said in a August 21 article that he hoped the contamination was not caused by the oxygen injections. He reiterated this to hospital officials at Monday’s council meeting and said he still hoped it was just a coincidence.

The town has hired an independent geologist to determine what caused the malfunction of Well #9.

Sipes side the Aquia Aquifer is used by many farms and homes in the area and not just the town of Chestertown, and that anyone drawing water from the aquifer should have been notified of the oxygen injections—even if the risk of contamination to the aquifer was minimal.

In July, the hospital turned off the remediation process which uses a series of pumps to draw ground water to the surface–where it is treated and discharged into the town’s storm water system. Other pumps pull loose fuel from the ground into holding tanks.

With the pumps now off, Sipes is concerned that any remaining contamination could be free to migrate towards the drinking wells.

Bullen said the hospital would still monitor the ground water and restart the remediation process in the event any remaining contaminants begin to migrate south of the Brown Street parking lot.

“This is just a trial shutdown,” Bullen said.”Everything is in place, all we would have to do is turn the switch back on if there’s problem.”

Bullen also said that at no time could the oxygen injections have migrated into the aquifer because the procedure was contained in a radius of 28 feet at the parking lot, which is nearly a half mile from  Well#9.  Bullen said there was also a 200 foot layer of clay between the contamination and the Aquia Aquifer, which Well #9 draws from.

He said the injections were further contained by the remediation pumps that were still in operation during the procedure.