A House subcommittee chairman accused the Energy Department yesterday of operating its nuclear reactors under a "double standard" by refusing to conform to commercial safety requirements and by fighting off state and local efforts to plan for emergencies.

Rep. Edward J. Markey (D-Mass.), in a hearing on federally operated nuclear reactors, said DOE "forcibly excluded" other federal agencies from its emergency planning process and showed "hostility" toward public involvement.

The department operates the nation's only reactors that lack reinforced containment domes to prevent the spread of radioactive particles in the event of an accident like the one that crippled the Soviet reactor in Chernobyl last month.

Assistant Secretary Mary Walker defended the department's actions, contending that DOE reactors have "a demonstrated record of safety" and many are on large reservations away from population centers.

"Our plans need to be uniquely tailored to the site," she said. "The strict regulations that pertain to commercial utilities are not always appropriate for our facilities."

But other witnesses said a major meltdown at any of DOE's reactors could release as much radioactivity as Chernobyl did. They questioned whether workers on the reservations and people nearby are adequately protected with evacuation plans.

According to internal documents obtained by Markey's Energy and Commerce subcommittee, the department has battled for more than three years to keep outsiders, including the Federal Emergency Management Agency and the Nuclear Regulatory Commission, from asserting authority over its emergency plans.

The documents suggest that DOE officials were concerned that state and local officials might use such authority to impede or shut down reactor operations or to "demand funds to plan for evacuations."

A 1984 memo from a DOE lawyer to Gordon Chipman, then head of the department's nuclear task force, warned that allowing FEMA a role in the planning would subject the department "to the same extortion by state/local governments that utilities currently face."

Walker yesterday disavowed knowledge of the memorandum. "I have never characterized state and local governments as extortionists," she said, adding that FEMA officials frequently consult with DOE safety experts on nuclear issues.

"Your agency has iced out FEMA," Markey retorted. "DOE has told FEMA to get lost. That's the bottom line. You are self-regulated and you don't want to let anybody else in."

The documents trace FEMA's attempt to review the department's emergency plans for civilian areas surrounding military reactors, including those at the Savannah River complex in South Carolina and the Hanford Nuclear Reservation in Washington state. DOE operates four weapons-production reactors at Savannah River and one reactor at Hanford that produces both electricity and plutonium for weapons.

None has a containment facility, and the Hanford reactor has come under intense scrutiny because it uses a graphite technology similar to that of the reactor in Chernobyl.

Walker, accompanied by officials from Savannah River and Hanford, told the panel that the reactors are protected by other means, principally a "confinement" building to filter out radioactive particles.

"Containment is not only not necessary but in some cases not appropriate for our facilities," she said.

According to Hanford official John Hunter, analyses of the reactor there indicate that the filtering devices would be adequate to withstand an accident in which one-third of the core melted down, roughly equivalent to damage sustained by the Three Mile Island (TMI) reactor in Pennsylvania in 1979.

But Thomas B. Cochran, a staff scientist for the Natural Resources Defense Council, said DOE's analysis assumed that a separate system to cool the reactor's graphite block continued to work.

"If that emergency system fails to operate, a graphite fire, and perhaps even a hydrogen explosion, appears highly likely," he said. The filters would quickly be overpowered and a catastrophe like Chernobyl's could result, he said.

Markey also questioned the "balance" of a blue-ribbon panel named this week by Energy Secretary John S. Herrington to review the safety of the Hanford reactor.

The six-member review board will be headed by Louis H. Roddis Jr., former president of Consolidated Edison of New York and of the Atomic Industrial Forum, and the vice chairman is Gerald Tate, a former Atomic Energy Commission member now affiliated with Associated Universities Inc., operator of DOE's Brookhaven National Laboratory. Two of the other members are university physicists and two are private consultants with industry ties, including Miles C. Leverett, one of the principal designers of the Hanford reactor.