Supporters of legislation to prevent U.S. EPA from regulating coal ash as a hazardous substance are taking issue with a recent Congressional Research Service report on House and Senate bills -- and may ask the research agency to rewrite portions of it.

CRS environmental policy analyst Linda Luther was candid in her assessment of the legislation, echoing many concerns voiced by environmental advocates. She said the bills "include no provisions" compelling states to adopt coal combustion waste programs that comply with minimum federal standards "necessary to protect human health and the environment."

The report contradicts supporters of H.R. 2273 and S. 3512, who say the bills allow states to administer their own coal ash waste programs under minimum federal standards. EPA would be able to intervene in certain cases.

Sen. John Hoeven (R-N.D.), chief sponsor of the Senate legislation, said many of the report's conclusions were incorrect.

"I've already asked to meet with CRS and go through and show them where we have provided the safeguards," he said in an interview.

Hoeven did not provide details of the meeting or whether he would press CRS to retract or modify its report.

"If we come up with something in there that needs more work, fine, then we'll address it," he said. "But we think safeguards are there."

Environmental advocates are hoping the CRS report makes lawmakers think twice about supporting the bills, which have been touted as a bipartisan compromise. It is unclear whether it has changed any minds.

"This report highlights that both bills would do little or nothing to change the status quo of coal ash dumps prone to leaking coal ash pollutants or catastrophic breaches," said Environmental Integrity Project attorney Lisa Widawsky Hallowell. Earthjustice attorney Lisa Evans said, "Congress must get out of the way and let EPA do its job."

A CRS spokesman did not discuss the ongoing dispute. "Linda Luther is unavailable to answer your questions," he wrote in an email yesterday. "CRS analysts work exclusively for Congress, and Ms. Luther is busy answering congressional requests."

Founded by an act of Congress in 1914, the Congressional Research Service is an arm of the Library of Congress. Lawmakers expanded the office in the 1970s. With a staff of about 600 people, according to a recent estimate, CRS has fulfilled more than 760,000 reports, information requests, briefings and other services for lawmakers and committees.

"CRS is not above error. Nobody is. Everyone makes mistakes," said Steven Aftergood, head of the government secrecy project at the Federation of American Scientists. "But the agency makes an intense effort to transcend the political passions surrounding many issues."

Aftergood tracks CRS research and reports, and says there is an ongoing debate over the office's role as a nonpartisan arbiter of information.

"They do not rely simply on the opinions or judgments even of individual experts," Aftergood said in an interview. "Instead they subject their product to multiple layers of review with the objective of providing fact-based analyses that will be useful to everyone concerned."

In an online post last year on the retirement of longtime CRS Director Daniel Mulhollan, Aftergood said new leadership may change the policy of "strict neutrality" in favor of more informed analysis.

However, he was not encouraged when CRS this year withdrew a report on taxes and economic growth amid Republican criticism. He said the CRS reissued a revised document with similar conclusions but less controversial language.

"I think they're getting gun shy, which I think is a move in the wrong direction," Aftergood said. "The fact they pulled the tax report, I think, is a declaration of weakness."

He added, "I hope they will stand up for themselves and defend the integrity of their own analysts."

Hoeven said he wasn't redrafting his legislation but was open to changes. "That's how we get Republicans and Democrats. That's what we're doing," he said. "We want a vote on the merits and the issue. I want to be real clear about that."

Bill boosters know that time is running out to find a vehicle for the legislation and that the wrong approach could turn off some colleagues. So, Hoeven said, he will bring it up when he and co-sponsor Sen. Max Baucus (D-Mont.) "both agree we get a straight-up shot."