(Updated, 6:00 p.m.)

PROVIDENCE – R.I. Attorney General Peter F. Kilmartin, accused the head of the Mass. Department of Environmental Protection of taking an "anti-environmental position … at the expense of our beautiful [Narragansett] Bay."

The matter, Kilmartin explained in a news release Friday, relates to a statement that "has just recently fallen into my hands as it was not originally sent to me or to the Department of Environmental Management even though it was dated last summer."

Kilmartin alleges that in the statement, which took the form of a letter to the regional administrator for U.S. Environmental Protection Agency's Region 1, Curt Spalding, dated July 20, 2011, MassDEP supported a request by the Upper Blackstone Water Pollution Abatement District – which operates a wastewater facility serving Worcester and surrounding towns – to allow the plant to "continue discharging pollutants into the Blackstone River at levels significantly greater than are allowed under the EPA's 2008 permit."

MassDEP Commissioner Kenneth L. Kimmell, in a telephone conversation with Providence Business News, denied that his letter made that request.

The plant is subject to a 2001 issuance from the EPA that was "supposed to last only five years. That permit, which remains in effect after its intended expiration, lacks any limit on the flow of nitrogen," Kilmartin contended in a letter to Rhode Island's congressional delegation. "Nitrogen (as well as phosphorous) causes eutrophication – the slow bio-chemical strangulation of a water body."

He asked the delegation to "help [him] counter the influence of the MassDEP which has weighed into the process with critiques of EPA that I find to be untimely and unsupported."

Kilmartin noted that wastewater plant, located in Millbury, Mass., had made "progress" related to nitrogen during periods of dry weather (the result of investments of about $180 million, according to MassDEP), but there is no limit "legally compelling" the entity to continue.

"I write to strenuously oppose and resist MassDEP's attempt to lend its name to an anti-environmental position. In the face of this challenge, Rhode Islanders cannot unilaterally disarm and complacently allow extra-judicial influence."

Kilmartin also asserted that the MassDEP's position was "unfair in light of the great sacrifices Rhode Island rate-payers are making to stop pollution of the upper Bay. The treatment plants located in the Ocean State have already cleaned-up or are in the process of doing so. While the Massachusetts situation threatens to fester indefinitely, the Rhode Island permitees are making rapid progress towards meeting those standards."

Kilmartin's position aligns with that of Environment Council of Rhode Island and the Conservation Law Foundation, he said.

Kimmell did not deny that the Massachusetts treatment facility, as well as others in Rhode Island, were discharging nitrogen into the Blackstone River. "That is not something that anyone would contest," he said.

The issue, he said, "is the treatment limits that should be applied."

Kimmell pointed to an April 2010 report published by the EPA's Science Advisory Board that criticized the agency's methods for determining nutrient quality criteria. "DEP was saying that there was new data that has been generated that could be relevant and we were recommending that EPA look at the new science before revising the permit. … We were not showing support for any particular permit level."

In fact, added DEP spokesman Joe Ferson, "we think this discussion could have been done in a matter of months, and might have led to an outcome that all parties could accept."