Twenty-seven years ago, Martha and Hartley Bailey came to Country Pond, a picturesque little lake outside Kingston in southern New Hampshire. On a sliver of land overlooking the water, they built a cottage that served as a weekend haven and, for the last decade, their retirement home.

Today, the lake is threatened by hazardous waste contamination.

For the Baileys and their neighbors, the environment has become the sort of issue that attracts profound attention in New Hampshire: a pocketbook and backyard issue, one that hits close to home.

Moving toward Country Pond in the ground water is a plume of industrial solvents from the site of a defunct barrel-cleaning business near the lake's western shore. Toluene, chlorobenzenes and other chemical contaminants have been detected in sediment samples near two small creeks that feed the lake from the west.

The site is on the federal "Superfund" cleanup list. Dozens of lake-front residents have abandoned wells and turned to bottled drinking water, and the Baileys have joined a growing number of New Hampshirites who say they intend to make the environment a major issue in the 1984 presidential primary campaign.

Hartley Bailey calls himself "a hidebound Republican" but says he will not vote for President Reagan in 1984.

Martha Bailey bridles at being called an environmentalist. But she said Sen. Gary Hart (D-Colo.), darling of the environmental set, "is ahead of everybody else" seeking the Democratic presidential nomination.

From hazardous waste to acid rain, from raw sewage flowing into the state's rivers to sulphate haze dimming the grandeur of its mountain vistas, environmental problems are hitting home throughout New Hampshire.

"Pocketbook issues have traditionally been the most important in this state," said Gov. John H. Sununu, a conservative Republican who last year unseated a Democrat who refused to take the state's famous pledge against sales or income taxes. "But people here are pragmatic about environmental issues. There is nothing like the zeal you'll find in Washington, where environmental lobbyists have lost touch with reality."

But, for what residents such as the Baileys see as solid, pragmatic reasons, there is environmental zeal in New Hampshire:

Despite the relative scarcity of large-scale industrial manufacturing, the state has identified more than 60 toxic-waste dump sites, most in the state's densely populated southern tier.

Seven are on the Environmental Protection Agency's list of 419 high-priority sites for Superfund cleanup, and more than $8 million has been spent to prevent further contamination of underground aquifers that supply drinking water for more than half of the state's residents.

New Hampshire is two-thirds of the way toward the national goal of "fishable, swimmable" waters, a significant accomplishment for a state whose rivers were considered among the nation's dirtiest a decade ago. But policy changes under the Reagan administration will cut sharply into federal financing of sewage-treatment plants, and state and city officials said their precariously balanced budgets cannot compensate.

Because of a state plan for cleaning up rivers from headwaters in the White Mountains south to Massachusetts, the other one-third of the task involves some of the state's largest cities, clustered along the southern tier. Manchester, the largest, still dumps one-third of its raw sewage into the Merrimack River.

In a state that lists tourism as its second-largest industry, with forest products not far behind, acid rain is seen widely as a potentially devastating economic issue.

"If you're going to be a vacation haven, you've got to pay some attention to your lakes," said Ronald (Deke) Towne, chief aquatic biologist for the state Water Supply and Pollution Control Commission.

"There's a big economic factor here," he said. "The real bottom line is resources. I don't think we can afford to cavalierly waste these resources. It wouldn't take much of a reduction in forest resources to knock northern America out of the timber market."

The monetary arguments hit home in the state's traditionaio) softened his position on acid rain after a visit to New Hampshire.Bailey to a toxic dump site in Epping.

"The administration's environmental record has got to be something Rith . . . ," said Paul Bofinger, president of the Society for the Protection of New Hampshire Forests, the state's oldest and largest conservation group.

The margin ctory on New Hampshire's acid rain resolution was both surprising and expected.

The state's political orientation is undeniably to the right. In Towne's words, "The people here are so conservative that if thu can throw away four kings."

But in a Washington Post poll in Manchester in late June, nearly 60 percent oescribed themselves as active environmentalists or sympathetic to the environmental movement. Only 4 percent said they are unsympathetic.

Officials here interpret thatsounding testament to another factor at work statewide: residents' desire to preserve the special character of their serene, spectacularly beautiful state.

To some, Nehire's environmental concerns represent a resurgence of old values, coupled with a renewed pride in the state's natural attributes.

Resideing able to see, for the first time, the golden sand bottoms of rivers near their homes.

State officials tding salmon last year in the Merrimack above Manchester's Amoskeag Dam after a 15-year effort to reintroduce them to a river devoid of salmon for more than a century because of dams and pollution.

"Twenty years ago, people wouldn't touch the oysters in Great Bay," said Dr. Bobl, head of the marine sciences department at the University of New Hampshire. "Seven rivers feed that bay, and they were all open sewers. Toe shellfish are edible."

Still, on New Hampshire's slender, 18-mile coast stands a towering monument to what some residents consider the greatest environmental challenge--the Seabrook nuclear power plant. The state's environmentalists lost that challenge, but some officials crthat defeat for awakening interest in many other perceived environmental threats.

"Seabrook came up at a time when New Hampshire was not of its coast," Correl said. "New Hampshire was sleeping when Seabrook came into being. But if Seabrook were toook couldn't happen."