The Environmental Protection Agency expected only good things to come of six "listening sessions" that it held around the country to examine how environmental problems such as poor air and water quality harm senior citizens.

Instead, by the time the last session was held in Baltimore last Wednesday the results could not have been more unexpected. The agency was battered by senior citizens, advocacy groups and environmental groups with complaints about how the administration was undervaluing lives of aging Americans in its regulatory analyses.

The acrimony that developed at meetings in Tampa, Pittsburgh, Iowa City, San Antonio and Los Angeles prompted EPA Administrator Christine Todd Whitman to cut her losses when she took the podium in Baltimore. Before any seniors could upbraid the agency again, Whitman said the EPA would no longer use the analysis that attaches less value to lives of senior citizens when it does calculations to figure out the benefits of environmental rules.

Normally, the EPA uses $6.1 million as the value of life in all its calculations, regardless of age. The alternative approach first prominently used in a clean-air policy initiative early last year reduced that value to $3.7 million per life, and then $2.3 million for citizens over 70. Critics seized upon it as the "senior death discount."

One group circulated a flier before the Baltimore meeting saying the EPA calculated "Seniors are Worth 3/5 of a Person."

"EPA will not, I repeat, not, use age-adjusted analysis in decision making," Whitman said in Baltimore. She added that the agency has not based any of its policy decisions on the discount.

In an interview, Albert M. McGartland, director of the EPA's National Center for Environmental Economics, said, "We will continue using our standard methods, which have been thoroughly reviewed."

Environmental groups, in general, have been dismayed at the administration's approach to calculating the benefits of rules. They have criticized the use of "alternative analysis" in several major rulemakings at the EPA, which resulted in drastically lowered benefits. The effect on policymaking, they contend, is that rules would not have to be as stringent and would actually harm the most vulnerable groups.

The groups saw the EPA announcement last fall about the "listening sessions" as a chance to make their criticism in person.

Prepped by public interest groups such as U.S. PIRG, senior citizens quickly became familiar with one of the more arcane regulatory concepts being debated among economists and policymakers: cost-benefit analysis and the assumptions used to determine how many lives are saved, or lengthened, by various environmental rules -- and how much people are willing to pay for that protection.

Before the Tampa meeting last month, PIRG representatives worked to get such groups as Florida Republicans for Environmental Protection and the Silver Haired Legislature fired up about the issue. Seventeen seniors showed up at the microphone to gripe about the discount.

Environmental groups alerted their members. David Certner, director of federal affairs for AARP, got wind of the controversy and told the Office of Management and Budget that the group -- which represents an influential voting block -- was "deeply troubled" by the use of "a 37 percent discount to the life value of adults aged 70."

The Baltimore Sun published a piece by Carol M. Browner, EPA administrator in the Clinton administration, the day of the Baltimore meeting, saying the Bush administration was devaluing seniors and letting polluters off easy. The press in cities where the EPA held the sessions showcased seniors who gave the agency a piece of their minds.

The controversy also has heightened tensions between the EPA and the OMB over using more than one approach to value costs and benefits. Economists at the agency have expressed discomfort at what they call pressure from the OMB to use alternative calculations that lower benefits of rules.

John D. Graham, administrator of the OMB's office of information and regulatory affairs, said the age adjustment has been removed from an EPA proposal to curb pollution from a certain class of diesel engines. He said the OMB was responding to "technical concerns" from economists and academics about the results of the underlying academic study that supported the age adjustment.

"I share Governor Whitman's conviction that an age-adjustment factor should not be used at this time to support a primary or alternative benefit estimate," said Graham in a written response to questions. "OMB remains open to additional evidence that may be published in the future."

Graham said another approach is to use "life expectancy" analysis that is based on the number of years of life saved by rules, and thus can place more value on the years that are left for older people.

Critics of the administration are not convinced the problem has been fixed. They say the economic analysis promoted by Graham will shortchange benefits in other ways.

"They [the Bush administration] use a number of techniques that result in the loss of value of all lives," said David Tuft, director of special projects for Breakthrough Technologies Institute, a nonprofit that promotes technology with environmental benefits. "The agenda is to weaken the justification for rules."

The OMB counters that under the current administration and the Clinton administration, the government has been exploring the best ways to quantify health benefits, taking into account economics, including diverse technical points of view, as well as ethics, such as the value of life.

Some economists studying cost-benefit analysis wanted to continue the debate. "For EPA to give up on this is a surprise," said Cass R. Sunstein, a law professor at the University of Chicago Law School who is an expert in risk assessment. Alan J. Krupnick, a senior fellow at Resources for the Future, a think tank that focuses on environmental policy, said, "I wanted to hear a debate on what is the appropriate way of evaluating life-saving programs that affect different age groups and different stages of health."

Research co-authored by Krupnick is part of the reason the OMB dropped the senior death discount. The work showed that an earlier Canadian study he worked on, which found seniors less willing to pay to reduce the risk of death, did not hold true in the United States.

"Life as you get older is more precious. That's the crux of our [new] study," he said.