Scientists are finding fault with Republican budget proposals that could close a quiet federal agency that tracks the world's earthquakes and has been a key player in the Bay Program for a decade.

The U.S. Geological Survey is on a hit list of federal offices circulated by Republicans in December as they prepared to assume power in Congress. Shutting the Reston, Va.-based agency could save $3.2 billion over five years, according to a GOP budget analysis.

"From both a policy and a science perspective it's a very, very poor idea," said Don L. Anderson, a geophysicist at California Institute of Technology and a leading earthquake expert. "This is one of the more professional, efficient agencies in government. It's very small and its scientists are among the best ... You can't say that for many other offices in the government."

The USGS's 10,000 employees, including about 2,000 at the Reston headquarters, monitor and measure earthquakes, floods, volcanoes and erosion. The USGS oversees a vast, highly automated international network of instruments that measure tiny seismic changes that scientists use to predict earthquakes.

The USGS has also been an active player in the Chesapeake Bay Program since 1984 when it became one of the first federal agencies to sign a cooperative agreement with the EPA pledging support for the restoration effort.

USGS collects and analyzes water quality samples from nine of the Bay's major tributaries to estimate the amount of nutrients entering the Chesapeake. The information is used to help evaluate the effectiveness of nutrient control efforts in the B ay watershed.

In addition, the USGS has programs to monitor the movement of pesticides, metals and other toxic substances entering the Bay from the Susquehanna, Potomac and James rivers.

Other USGS activities in the Bay watershed have included studies of groundwater contamination and movement, water flows into the Bay, evaluations of specific nutrient-reduction strategies, and other water-quality related topics.

Direct USGS support for Bay Program activities in 1994 was $2.6 million, while indirect support was put at more than $25 million.

"We believe the work we do affects every citizen every day," said agency spokesman Don Kelly. "We're not sure how else our duties could be done as effectively as we do them."

Eliminating the USGS has been part of GOP budget proposals for two years, but the idea gained new immediacy on Election Day, when Republicans gained their first majority in Congress in 40 years.

In December, the House Budget Committee's Republican staff came up with the list of dozens of possible cuts to offset a proposed $500 per child tax credit included in the Republicans' Contract With America. But GOP staffers have been quick to say nothing has been decided.

"It's a list of examples of ways you could cut," said Ed Gillespie, spokesman for the House Republican Conference. "There are a lot of things on the table."

Some of the 115-year-old agency's duties would go to other government offices, the GOP budget plan said. For example, the now-academic National Science Foundation could assume the technical functions of earthquake monitoring, the study said.

"That doesn't make any sense," Anderson said. Trying to parse out the USGS duties would probably cost money, at least in the short run, he said.

Newly elected Rep. Thomas M. Davis III will argue for keeping the USGS, which is in his district.

"We're certainly not going to take any chances," the freshman Republican said.

Although he signed the Contract With America as a candidate, Davis said the legislative road map is flexible.

"There are no specific cuts in the contract ... There are going to be cuts in various federal agencies, but I don't think it makes sense to cut an agency that plays a very vital role, Davis said.

The USGS is little-known outside scientific circles. It gathers and interprets data on earthquakes and other geological events, as well as producing detailed seismological maps. The mapmaking function would be eliminated under the GOP plan, under the theory that anyone who needs such a map could pay to produce it privately.

"I believe that anyone who knew what the USGS really does would think it is a valuable and efficient agency," Anderson said.