Officials here say a proposed industrial airpark will generate 1,800 jobs, add sex appeal to the county's business recruiting efforts and generate $1 million in profits by 1998.

This week, consultants from Greiner Engineering Science Inc. of Baltimore recommended that the proposed 1,000-acre airport and industrial park be built in the heart of Charles County's growth district, just northeast of La Plata and within easy access of Route 301 and the Conrail line from Baltimore to Morgantown.

The county's economic development office will now recommend that a formal environmental assessment be done as the next step to qualify for Federal Aviation Administration construction and land acquisition money.

The new airport and industrial complex could open as soon as 1987 if the FAA approves this environmental study and the county commissioners give the green light for construction.

In an $83,000 economic feasibility study his firm conducted,, Greiner airport engineer Michael Steer said the site's central location and access to sewer and water hookups were big development pluses that helped give top ranking to the site over 11 other locations studied in the past year.

Two other sites were ranked lower in one case because power lines ran across the proposed runway and in the other because the county would have to build its own sewer treatment facility.

While the cost of the proposed airport with its initial runway of 4,042 feet has not been determined, 90 percent of the land and runway costs would be paid for by the FAA if the airport is approved as a public facility, with the state and county each picking up 5 percent of the project's costs. The cost of the feasibility study is being split using the same formula, said Peter T. Melia, FAA airport planner.

The county will pick up costs for airport hangars, maintenance and outlying buildings and earn income by selling fuel and land in the industrial park and renting T-hangars, officials said. The county-owned and operated airport will be equipped with more sophisticated navigational aids than any of the three other privately owned landing sites in southern Maryland, making it a more attractive alternative, officials said.

Steer estimated that an initial investment of $3.75 million would be necessary for the first five years of the airpark's development with a total project investment near $10 million over 20 years.

"Revenues will exceed costs over the project's first 20 years," Steer said. He said the 500-acre industrial park will basically subsidize the airport during its first six years of operation, but the total complex will make a $1 million profit after 10 years with the industrial complex paying for itself after six years.

The county is pushing the airpark concept to lure new industry and thus bolster its tax base -- which is diminishing even as its school-age and elderly population is on the rise -- and to create much-needed jobs.

"Our tax rate will have to go up in order to provide services for these groups. It's a question of how much the homeowner will bear. . . . That's why it's important to attract new business," said Ray Tilghman, executive director of the county's economic development commission.

In the past decade, Charles County has grown by 20,000 residents to become the state's fastest growing region. By the year 2000, with only a 2 percent annual growth rate, the county is expected to be home to 109,000, up from its present 83,000 residents.

"Most of the community is just not familiar with economic development and its importance to the community," said Economic Development Commission Chairman Wills J. Blacklock. "There are great pressures on us from a financial standpoint," he said.

Blacklock said a recent Council of Governments study showed that 63 percent of the county's work force left the area to find jobs in 1983. This compares with the 20.5 percent who commuted elsewhere to find work in 1960.

"We are a bedroom community with a tremendous labor force. . . . Unless something changes, 78 percent will have to leave the county by the year 2000," Blacklock said.

Tilghman said the county will aim its marketing pitch for the industrial/airpark site at research and development firms that dot the landscape in Montgomery and Fairfax counties but are looking for less expensive real estate on which to build satellite operations. "Our labor market and tax rates make relocation or spinoff operations here very palatable," Tilghman said.

In 1983-84, Charles County's tax rate was $2.14 per $100 assessed valuation, compared with $2.44 in Montgomery, $2.54 in Prince George's, $2.57 in Howard and $1.99 in St. Mary's County, according to a report published by the Maryland Association of Counties.

A spokesman for the FAA said federal studies have shown for at least five years that another airport is definitely needed in southern Maryland. "The 170 aircraft now based at P.G.'s Hyde Field Airport (in nearby Clinton, Md.) shows people are using the facility and there is a demand," Melia said.

Hyde Field Airport -- which is now up for sale -- Prince George's Airpark and Maryland Airpark in northwest Charles are all private facilities with runways in the 3,000-foot range. If the extension is built, the Charles runway will be about 5,500 feet.

Noise, and its impact on surrounding residential communities, was a major community concern and a big factor in ranking proposed sites. During the environmental study, the effect of expected noise levels on the nearby community of Kings Manor -- a mile away -- will be studied in detail, Steer said.

Daily takeoffs and landings are expected to total an average of 74 by 1990 with 37 small aircraft based at the site. By 1998, based aircraft are expected to number 100 with daily operations totaling an average of 148, the Greiner report said. These numbers will triple by 2007.

"Noise is a legitimate concern. But it is premature before the environmental study is complete," Melia said. "The vast majority of the planes that will be using that airport -- at least before the runway extension is built 10 years down the road -- are not the noise-generating type. . . . Hopefully they will build the airport and use the zoning to protect the surrounding community."

Throughout the past year, the Chesterfield airpark outside Richmond has served as a model for county planners. Like Charles, Chesterfield is the fastest growing county in its state and lies just outside a large metropolitan area.

Since it opened in 1972, Chesterfield has attracted 400-plus jobs and 44 businesses, including the international headquarters of a division of Reynolds Metals. At least three companies have based small corporate jets at the site.