Park Service chief defends 6-month record. Conservation groups say he may not be as effective as they first hoped

After six months in office, the honeymoon between National Park Service director William Penn Mott and key environmental groups is coming to an end. Mr. Mott thrilled conservationists when he charged into office last May. He was a personal friend of President Reagan, having headed California's park system when Mr. Reagan was governor. He carried impeccable environmentalist credentials, and, outspoken as he was, promised to provide assertive Park Service leadership. Many environmentalists eagerly awaited fast and bold steps from the new director to remedy park problems that include overcrowding, sagging Park Service employee morale, and threats

from surrounding lands.

But six months after Interior Secretary Donald P. Hodel named him as the new steward of the nation's 347 parks, Mott has learned that things take time when you're head of a $1 billion-a-year federal bureaucracy. ``It probably takes a little longer to get things done than I anticipated,'' Mott said in an interview.

Environmentalists still hail Mott as an energetic promoter of the parks and credit him with several important initiatives. They note he has taken badly needed steps to boost morale. At a time when the Reagan administration has slapped a moratorium on aquiring new park lands, they applaud the leadership Mott has showed in advocating two new additions to the National Park System, one for a Tall-Grass Prairie National Park and the other for a Wild River National Park. He has replaced every James Watt-era p olitical appointee with one of his own. And, they add, he has only been in office a short time.

Nevertheless, the environmental community is beginning to worry that Mott will not be as effective as it once hoped. Environmentalists are concerned that Mott's superiors at the Interior Department have a different agenda, and that Mott is being forced to abandon or dilute many of his ideas.

``I think it's a little disappointing,'' says Clay E. Peters of Mott's tenure so far. Until recently, Mr. Peters was director of national-parks programs for the Wilderness Society, a Washington D.C.-based environmental group. ``He said some very refreshing and very exciting things, things that are right on target as far as the needs of the Park Service are concerned. But it seems that he is changing.''

Many environmentalists say they are concerned that Mott's widely hailed 12-point plan to provide the parks with badly needed direction to carry them into the 21st century may yet become a jumble of platitudes rather than a hard-nosed recipe for reform. They are closely watching two Mott decisions this week, both on the hotly contested issue of upgrading roads in the parks, as an indication of the actions Mott may take in the future on other issues.

Conservationists site two recent incidents as evidence that Mott's grip on the park system may not be as tight as they once hoped. For example, two weeks ago, Mott testified before Congress on the area surrounding Yellowstone National Park. The land in question, though outside of park boundaries, still has an important influence on the ecology of the park. Many observers expected Mott's testimony to echoing a ringing speech he gave in June at Yellowstone Park in which he said, ``When in any doubt we must err on the side of preservation.'' Instead, many thought the testimony equivocated when he didn't restate that position.

``It was a dismal disappointment,'' says T. Destry Jarvis, executive vice-president of the National Parks and Conservation Association. A number of people who said they saw earlier drafts of Mott's statements said his strongest ideas were cut out by his superiors at the Interior Department.

Then last week, Mr. Hodel announced that he would not designate for protection 136 so-called ``integral vistas'' -- especially scenic panoramas located outside park boundaries -- in 43 parks from pollution or development. Environmentalists decried the decision and said it did not bode well for Mott. Mott shruggs off such charges with easy certainty and gives no quarter to any of his critics.

He says that any changes in his Yellowstone testimony reflected his ideas, and that he has not been under pressure from Hodel to modify his views.

Next week in Tucson, Ariz., Park Service regional directors are scheduled to meet to consider ways to implement Mott's 12-point plan, although he admits progress has been slower in developing the program then he thought it would.

``I know there are the naysayers who say I won't be able to get the 12-point plan into action, that it's going to be too expensive, or whatever,'' he says. ``They're wrong. I'll get it through.'' -- 30 --