Seeking a balance between oil development and the environment, the Clinton administration has drawn up a plan for the restricted sale of new oil leases on Alaska's North Slope.

Details of the lease sale, which will open parts of a vast federal petroleum reserve in northern Alaska to oil drilling, were being an-nounced Thursday by Interior Secretary Bruce Babbitt.Development of the government's National Petroleum Reserve - an area the size of Indiana - in far northern Alaska has been con-troversial for years.

Conservationists fear oil production will harm ecologically critical wetlands, lagoons and marshes that dot the reserve's coastal plain and each summer attract millions of migratory birds as well as caribou and polar bears.

But oil executives contend the fields can be developed and wildlife and its habitat protected at the same time. They also argue that unlike the Arctic National Wildlife Refuge farther to the east, the National Petroleum Reserve was set aside specifically for development 75 years ago.

Just west of the Prudhoe Bay oil fields, the federal reserve was created for the Navy in 1923 to ensure the nation's access to oil. Estimates on the extent of oil deposits beneath the reserve's tundra have ranged from 400 million barrels to more than 3 billion barrels.

Except for unimpressive exploratory drilling in the 1940s and again in the 1980s, the reserve has been largely ignored as industry until recently concentrated on the adjacent and much larger 12-billion-barrel Prudhoe Bay fields.

Babbitt said Wednesday any development plan would have to be "a balance based on good science and broad consultation" and take into account protection of "sensitive environmental resources . . . while recognizing the intent of Congress in designating this area a petroleum reserve."

While leases will be offered for bid, the plan is expected to fall short of what oil companies have sought: Freedom to drill with few restrictions throughout a 4.6 million acre area in the northwest corner of the reserve including in an ecologically sensitive coastal plain.

On the other hand, environmentalists are questioning why the region east of oil-rich Prudhoe Bay should be opened for drilling at all when the world has plenty of oil.

"The world is awash in oil," said Bill Reffalt, director of Alaska programs at the Wilderness Society. "We've got it selling at $14 a barrel. Why are we in such a big hurry to start developing oil and gas (there now) at a fairly substantial cost to the environment?"