PRESQUE ISLE — Up to 300 people in Aroostook and Somerset counties could find work at two proposed copper mines described Wednesday at a symposium at the University of Maine at Presque Isle.

In addition to millions of dollars spent already on exploration, the companies projected combined annual payrolls of almost $8 million.

Boliden Resources Inc., a Swedish-based mining firm, owns the mineral rights to a copper and zinc deposit near Bald Mountain, 12 miles west of Portage. BHP-Utah Minerals International from San Francisco has proposed a mine at Alder Pond, just south of Jackman.

Depending upon what will be required by regulations being formulated by state agencies, operations at the mines could begin by early to mid-1990s.

The Alder Pond deposit is about 3.4 million tons of zinc, copper, lead and silver sulfide minerals. According to Chris Mattson of BHP, the company plans to construct a declining tunnel to further explore the deposit from underground. The mine could last at least 10 years.

The project manager, Rock Funston, said the primary environmental concern regarding the copper mine is surface and ground water.

During the initial exploratory phase, about 10 acres will be disturbed, while a full mining development would employ about 30 acres, with an additional 20 acres for a tailing, or waste disposal pond.

According to BHP officials, about $2 million has been spent on the project’s exploration since 1982, and another $1 million will be spent on baseline information.

The company has projected spending $60 million for capital investment, $40 million for wages, $20 million in federal and state taxes and $120 million for other expenditures over the life of the mine.

A copper mine in Aroostook County could employ up to 130 people and pay from $2.2 million to $3.3 million in annual wages. In state excise taxes, the company may pay up to $500,000 annually for the life of the mine.

Boliden plans to spend up to $1.25 million to collect environmental baseline data even before a mining permit application is filed with state regulatory agencies.

According to John Cesar, the company’s goal is to balance “environmental consideration, technical practicality and economic feasibility” in mining the Bald Mountain deposit.

Cesar said there “is no assurance” that state mining regulations will allow mining in the state and there’s “no guarantee” that an application will be approved.

Because of the lack of mining rules, the road to opening an mine will take time, Cesar said. “We can’t play the game if we don’t know the rules.”

Depending upon what state regulations require, the earliest a mine could open is June 1993, and the latest is July 1994.

The Bald Mountain geologist, Michael Scully, explained that the deposit measures 1,000 by 800 feet and contains an estimated 36 million tons of material. Erosion control ditches and a pond to collect deposit run-off have been constructed.

From its discovery in 1977 to 1988, 508 test drill holes have been dug at a cost of $8 million to the deposit’s previous owners. This year, Boliden has drilled 12 additional holes at a cost of $150,000.

Howard Lewis, who would handle the permitting process for Boliden, detailed the company’s plan for following environmental studies on the proposed mine site: air quality, $160,000; surface water quality, $250,00-$300,000; ground water quality, $250,000-$300,000; aquatic ecology, $80,000-$120,000; terrestrial economy, including plants and animals, $75,000-$100,000; and wetlands, $15,000-$25,000.

Up to $200,000 will be spent to study other land uses in the area, the socio-economic impact, traffic, and noise, Lewis explained.

The mine manager, Mike Robb, expects to operate an open pit mine. During the first two years, the gold and silver portion will be mined, Robb said.

The mine operation would require between 5 to 15 megawatts of electricity, which may be wired in through the Fish River Road. The road also would be upgraded for year-round use, Robb said.

Pelle Sandgren, who would manage the mill at the mine, said that the mill would utilize between 1,400 to 2,600 gallons of water per minute. As a comparison, an average potato processing plant uses about 3,500 gallons a minute, Sandgren explained.