If the issue of the environment is to figure anywhere in the presidential election, it would be here in New Jersey, a state so awash in environmental problems that it has been called "the landfill of opportunity."

New Jersey is home to more dangerous toxic dumps than any other state. A swath of the New Jersey Turnpike, center of refining and petrochemical industries that generate a stew of hazardous wastes, is known as "Cancer Alley." Flaking asbestos plagues schools, acid rain threatens rural lakes and the first discovery of an urban spill of dioxin -- the suspected carcinogen that forced the evacuation of an entire Missouri town -- came at an abandoned chemical plant in Newark last year.

Not surprisingly, the Eagleton Poll of Rutgers University found that New Jersey residents rate toxic waste cleanup the No. 1 domestic concern, dwarfing unemployment and inflation.

Moreover, few issues provide a starker contrast between President Reagan, who presided over a major controversy involving the Environmental Protection Agency's toxic waste cleanup program, and Walter F. Mondale, who worked as vice president to create the $1.6 billion "Superfund" to clean up such waste.

But the Reagan and Mondale campaigns agree on at least one thing about the environment -- it does not seem to be influencing the election here at all. A Washington Post-ABC News poll earlier this month showed Reagan leading Mondale 56 to 35 percent in New Jersey, and dozens of voters interviewed around the state recently said they are scarcely considering the issue in choosing between the two men.

Take Jane Cahill, who lives in Logan Township, across the street from New Jersey's most infamous toxic dump and within walking distance of three others. Hers is one of 13 households that must drink bottled water because of toxic leakage from the Bridgeport Rental and Oil Services dump here. The EPA was supposed to clean it up but is still debating how to proceed.

A registered Democrat, she put on a Mondale button in May and attended the kickoff of Mondale's New Jersey primary campaign -- an environmental stump speech beside the mucky Bridgeport lagoon, whose stench she smells almost daily.

Today she says she is undecided, leaning at times toward Reagan.

"Everybody says they're going to clean up that rotten dump, but it has been here through Democrats and Republicans," Cahill said, her face taut with frustration. "Why should I believe one man is going to make a difference? These are human beings here who are being killed -- slowly. It's like Russian roulette. I've decided I'm tired of being a political pawn -- Democrats, Republicans, Socialists, I don't care who they are."

Mondale may have won the contest over environmental records, but winning votes is another matter. While voters nationwide rank the environment in the top five issues for their future, they scarcely mention it here or elsewhere when asked how they choose a president.

"You could tell half the people in Logan Township that they were running Ho Chi Minh and it wouldn't make any difference after what we've seen," said Susan Andrews, a secretary, wife of a union electrician and organizer of a local grass-roots environmental group.

The frustration of Cahill and Andrews is extreme because of firsthand exposure to the dilemma of toxic waste. But voters expressed the same feelings in interviews last week throughout New Jersey.

In East Windsor, an affluent Trenton suburb targeted by the national League of Conservation Voters in an environmentalists-for-Mondale canvas, interviews with several dozen voters turned up intense environmental concerns, but a conviction that the issue is too amorphous to fit in a presidential race.

"Oh God, I know, I know," schoolteacher Bea Fanelli told a canvasser who warned that Reagan "has the worst environmental record in presidential history." As Fanelli closed the door, she said sheepishly: "I don't disagree with you, but I can't vote for Mondale. I don't want my taxes to go up to pay for somebody who doesn't want to go to work."

Most voters interviewed in East Windsor, which supported Carter in 1976 and Reagan in 1980, said they will vote for Reagan because they believe he is better for their pocketbooks. New Jersey, a growth area for service industries, now has an unemployment rate of about 6 percent, well below the U.S. average.

The environment is what pollsters call a "second-tier issue" -- one of a "cluster" of quality-of-life concerns that may affect voters more than they realize. Democrats say they will try in the campaign's final month to elevate the issue by linking it to Mondale's big themes -- such as fairness (favoring the public over polluters) and the future (regulating industry more today for a safe environment tomorrow).

New Jersey is the state that environmentalists, who are working actively for Mondale around the country, expect to reach first.

The Eagleton poll found that 83 percent of the people here consider toxic waste cleanup a "very serious" problem, outpacing unemployment (52 percent) and inflation (44 percent), the dominant domestic issues in national polls.

The state is home to two leading congressional critics of the Reagan environmental record -- Reps. James J. Florio (D), sponsor of the Superfund, and James J. Howard (D), chairman of the Public Works and Transportation Committee that was at the forefront of last year's EPA investigation. Thus voters already have been bombarded with anti-Reagan environmental messages.

Sen Bill Bradley (D-N.J.) is also an environmental spokesman, but Mondale organizers have had trouble mining environmental sentiments among Bradley voters for an all-too-familiar reason: Bradley, who is considered a shoo-in for reelection, is keeping his distance from Mondale.

One of Mondale's problems may be the cynicism of New Jersey voters on the issue, according to political consultant Barry Brendel of New Brunswick. Since the Superfund passed amid fanfare in 1980, not one dump here has been cleaned up. Only six nationwide have been cleaned up out of an EPA list of 786. New Jersey has 95 sites on the list, more than any other state.

This appears to have fed a deep distrust here toward the federal government on environmental matters. Voters' attention is focused more on local and congressional races than the presidency. Logan Township, with only 3,200 residents, has five grass-roots groups dedicated to lobbying local officials on environmental issues.

"As we see it, there is no viable, functioning government body to deal with so we've got to protect ourselves," said Mayor Frank Iacobucci.

Iacobucci and six Logan Township residents -- including Cahill and Andrews -- gathered recently at the home of Esther Slusarski, secretary of the local board of health, to discuss the Bridgeport dump. Although the exchange sounded at times like an excerpt from Mondale's fairness speech, most said they were leaning toward Reagan or undecided.

"It's the big oil companies that create the waste, and they're the ones that put all the money in presidential campaigns," said Sarah Dipietro, a homemaker and Reagan supporter. "So how can you fight Exxon, Mobil or Shell Oil? You're not going to win."

"It doesn't matter what's right or legal or humane," said Andrews, who is undecided.

"Why would anyone protect us when at most we've got 1,600 votes?" said Iacobucci, who declined to state his preference.

What appalled them most about Reagan was that he named chemical and oil company officials to posts at the EPA. But Mondale's promise to take their side has not won them over because they remember the Carter administration EPA as insensitive too.

The EPA under President Jimmy Carter filed a lawsuit documenting contamination of their water supplies, but people here did not learn that their drinking water was threatened until Slusarski read the lawsuit and told them.

"What it means is we can't take the issue that's most important to us to the voting booth," said Andrews. "If you care about unions, maybe it makes a difference because Mondale is pro-union and Reagan is pro-business. Or maybe on abortion it makes a difference. But this is so much more complicated."

"People talk about the war-and-peace issue, but this is more life-threatening to us than war," said Iacobucci. "People in Beirut are living with the war. We're living with the environment."

But they are voting on other issues. Andrews said she may vote for Reagan because she is anti-abortion, and Cahill because as a taxpayer she is "sick of giveaways," which she associates with Democrats. But both said they also saw reasons to vote for Mondale.

Slusarski is supporting Mondale, largely because she trusts Florio, her congressman, who has endorsed him. George Walter, a retired Mobil Oil engineer, is supporting Mondale because "he won't cut Medicare and I figure I'll need it if I keep drinking this water."

Undaunted by the polls, environmentalists are pressing ahead with a massive canvass in New Jersey that aims to contact 400,000 voters by Election Day. The League of Conservation Voters, the largest environmental political action committee, is also running anti-Reagan radio ads throughout the state.

Last week, as league canvasser Peter Allison worked the split-level homes along Oxford Drive in East Windsor, he found overwhelming sympathy with his environmental views but few takers for Mondale.

"I agree with all of these," said Gerard McCarthy, agreeing to sign a statement of concern about toxic waste and water and air pollution. But when Allison asked how he planned to vote, McCarthy rolled his eyes, put his hand to his forehead and said:

"Why didn't the Democrats put up somebody more 'into it?' I think they would've had a good shot. Reagan's too old. He's too pro-war. But I just don't see where I have any choice but to vote for him."

Still, Allison pressed his case, sometimes hitting pay dirt.

"I'm voting for Reagan," Pam Carpenter told Allison, but there was some hesitation in her voice. The young canvasser then gave an earnest critique of Reagan's record and Carpenter asked him to leave her a copy of his leaflet, which begins: "On Nov. 6, vote as if your future depends on it. It does."

"I'm going to have to look more closely at this," she said. "It's too important not to, isn't it?"