HAMPSTEAD -- It was over 12 years ago when Walworth B. "Wally" and Mary Lou Williams started the Hampstead Trails Committee to preserve old trails and build new ones on town-owned land.

Every Monday evening found the couple at trail-cutting parties, where they and other committee members would clear trees, roots and stones off trails. At summer's end, the trails opened to the public.

The trails and other ecology-minded contributions haven't gone unnoticed: Wally Williams, 84, is one of seven New Englanders to win the Environmental Protection Agency's Environmental Merit Lifetime Achievement Award. Mary Lou Williams, 83, nominated her husband for the honor. More than 100 people were nominated, said EPA spokesman Andrew Spejewski, who added recipients needed to have worked to meet an environmental challenge or need.

Hampstead was the first town in Southern New Hampshire to create a Trails Committee to care for trails on conservation and town owned land, said Mrs. Williams.

"We decided it would be nice to have a townwide trail system," she said. "The idea is that anyone can walk out of their door and very shortly be on a trail."

And the Williamses, of Winchester, Mass. -- who have spent every summer for the past 60 years at their summer home on Big Island Pond in Hampstead -- still get phone calls from people in other towns asking them for guidance about trail systems.

Wally Williams was presented the award at the 33rd New England Enviromental Achievement Awards ceremony held at Faneuil Hall in Boston in April. When his wife received a letter from the EPA asking her whom she would like to nominate for a lifetime achievement award, Williams was the first person she thought of.

"He is a natural leader," she said. "He is very well liked and gets along well and works well with other people. His impact on Southern New Hampshire is tremendous.

"Without Wally's hard work over 1,000 acres of watershed land around Big Island Pond, in Hampstead, Derry and Atkinson, would be built on and not preserved forever by conservation restrictions."

She added that, without her husband's efforts, the Big Island Pond Corporation wouldn't be as effective an organization for "protecting the lake from pollution, overcrowding, unsafe boating and wildlife-habitat destruction." He was the treasurer and corresponding secretary and also edited a newsletter for the organization's 400 to 500 members.

Wally Williams has also been involved in the protection of New Hampshire forests, the New Hampshire Lakes Association, and the New Hampshire Timberlands Association.

But Williams credits his wife for their success.

"The two of us have done so much work, she worked harder," he said. "I think that Mary Lou deserves more credit with the success of conservation work than she got. A lot has been credited to me but not to her."

But he said he was flattered "and very pleased to have been recognized." However, Karen Hanides, a member of the town's Conservation Commission, credited both the Williamses for helping conserve land in Hampstead. "They started the trail system and have bought hundred of acres of land and bought trails and have been doing this since 1986."

Wall Williams said he and his wife have always worked together on every project, and they both have plaques and merit certificates adorning their summer home walls. Over the years they have also bought about 200 acres of land around Big Island Pond to preserve it.

"We love this lake and the more buildings the more pollution," Mary Lou Williams said.

They have long been active in the effort to preserve the state's forests and lakes, but the first "big" project they worked on was 20 years ago with the abandoned railroad bed that runs through 10 towns, from Hudson to Fremont. The local highway department was going to sell the land to a builder. However, the Williamses began meeting with several conservation commissions and similar groups from surrounding towns, and worked on ways to to discuss how they could forestall development.

Wally Williams then planned a hike with the Audubon Society of New Hampshire and invited state officials to hike the trail and see the beauty surrounding it.

"The hike resulted in a new law which stated no department in the state of New Hampshire could sell property without offering it to every other department," Mrs.Williams said.

And even though they are unable to physically cut down trees to create new trails, the Williams are still active in the Trails Committee and attend summer meetings.

"Its a nice recreation thing for people to enjoy," she added.