The long arm of the Environmental Protection Agency is reaching out to the local town dump _ and the huge metropolitan landfill as well. EPA, in its first major effort to regulate the land disposal of household trash and garbage, is proposing rules that officials say would force nearly every municipal dump to take steps to protect the environment. Announced Wednesday, the plan would require all of the nation's municipal solid waste landfills to install often-expensive monitoring equipment to detect pollution of groundwater supplies. The proposal, not expected to be popular with local governments, would require the cleaning up of dumps found to be leaking contaminants into underground aquifers. The draft regulations would force operators to put waterproof covers over dumps when they are closed and would set restrictions on where a new dump can be located. Many dumps that open after the rules take effect, probably not before 1991, would have to install bottom liners to prevent leakage and have systems to collect the polluting liquids found in dumps. ``It's a very strong protective rule,'' said J. Winston Porter, assistant EPA administrator for solid waste and emergency response. ``In some cases, people are going to have to spend a lot of (compliance) money.'' The plan would leave many compliance details up to states, so long as a dump did not impose any greater danger to humans than a 1-in-10,000 chance of contracting cancer from water contaminated by a dump's leachate. Porter told a news conference that states would have flexibility to operate their own compliance programs with an underlying proviso: ``We don't care what you do, but you cannot leak.'' The proposal would apply to an estimated 6,000 solid waste landfills _ 78 percent of them owned by local governments _ that handle about 80 percent of the 160 million tons of household refuse produced each year, he said. At least one of every four municipal dumps is believed to be violating one or more state groundwater-protection standards, he said. Porter said the dangers posed by municipal dumps can be seen in the ``Superfund'' priority cleanup list, where nearly one of every five facilities awaiting decontamination was once a municipal solid waste landfill. Around the nation, less than a third of the operating dumps have groundwater monitoring systems, only 15 percent have bottom liners and only 5 percent have leachate collection systems, according to EPA. ``Almost all landfills will have to do something,'' Porter said. ``There are very few landfills that meet all these requirements.'' He said he could not estimate precisely how much cost would be added to the nation's annual $4 billion to $5 billion bill for dumping, burning and recycling its trash and garbage. One EPA control scenario estimated the extra cost could reach $800 million a year, or about $11 per household. ``It will add something to the homeowner's bill,'' Porter said. ``We don't think it will be dramatic.'' He said he expects positive reaction from states because they will have flexibility to structure their dump-control programs to meet particular hydrogeologic and topographical conditions. ``I think we'll get two other reactions: local governments will say this is too expensive and environmental groups will say it isn't strong enough,'' Porter said. He said the higher dump operating costs under the proposed rules could nudge local governments to make greater efforts to recycle trash, a move that could aid EPA's national goal of recycling 25 percent of all household refuse. EPA expects to take a year to obtain public comment on the proposal before making it final, Porter said. Dumps would then have 18 more months before they had to comply with the requirements. He said some dumps might close to evade the proposed rules, a move he acknowledged would leave them without leakproof covers unless they are in one of the handful of states that now require them.