The 1,500 students in the Quantico Marine Base school system, which is run for children of Marines living on the base, may have to be transfered to public schools this fall unless Congress acts soon to keep their schools open.

Quantico is one of 23 military installations nationwide that have independent school systems for military dependents on post, a carryover from an era when military bases were in isolated areas far from existing public school systems.

The school systems, once under the Defense Department, are now financed by the Department of Education with funds from the so-called "Category 6" of the federal government's impact aid outlay.

The most commonly known form of impact aid -- Category 3 -- is the money given to local school districts for educating children of federal employees to compensate for the loss of revenue from untaxable federal property and personnel who pay taxes in their home states.

But Section 6 schools are operated or contracted out to local school systems by the military. In Quantico's case, the three grade schools and combined intermediate and high school are operated by the base rather than neighboring Prince William and Stafford counties. A civilian superintendent and an elected school board run the Quantico system with a budget of $4.6 million.

"There would have to be some kind of working relationship designed by (Prince William and Stafford counties) to run these (Quantico) schools if they were closed," said Quantico superintendent John C. Harcharek.

Nearly $75 million was budgeted to run the military's 32,900-pupil Category 6 schools next year. But, by the time the Senate and House finished voting on the administration's budget cuts last week, the future of Category 6 funding seemed in jeopardy.

The Senate, in approving $500 million in impact aid funds last week, stuck to the traditional distribution formulas for dispensing the aid. Its action preserves Section 6 funds although a specific amount was not earmarked, according to Senate staff members.

But the House, in approving the $40l million requested for impact aid by the Reagan administration, specifically deleted Section 6 funds, according to House staff members and Frances Michalkewicz, the Department of Education official in charge of impact aid programs.

If the Section 6 funds are not restored in the House-Senate conference on the budget cuts later this month or by separate legislation, Michalkewicz said, "I would assume (local school districts) would legally or on general principle pick these children up. . . . But I would hope this (funding) would be resolved because it's a critical issue."

There have been other suggestions on Capitol Hill for continuing the funding of Section 6 school systems. The most popular would have the Defense Department pay the costs of operating the schools. The House version of the impact aid bill that passed last week would, in fact, allow the Defense Department to pick up the tab.

That bill passed in a flurry of confusion that sent many Hill staffers scrambling this week to determine just what had been left in and what got scrapped.

"It was really ridiculous, an outrageous way to legislate. That House bill was all fouled up," said a spokesman for Rep. Stanford E. Parris (R-Va.), whose district includes Quantico. "But our impression is that we have a pretty good chance of getting the Senate (version of the) bill passed."

School administrators in Prince William and Stafford counties hope so. They are already smarting from the anticipated loss of all Category 3 impact aid and doubt their school systems could easily abosorb the Quantico students if the base schools are shut. They also have no idea how the projected fall enrollment of 1,552 Quantico students would be divided between the two counties.

"That's quite a few children to move into our system," said Richard Chapin, associate superintendent for management in Prince William's 35,000-pupil system. "For the children living on the base there would be quite a bit of busing involved because we don't have many schools in that area. . . .

"We would have to look at the student population, what ages they are, where they live before we could figure out the busing and number of teachers that would be involved. . . . It would be annoying because the budget and tax rate are already set."

Andrew G. Wright, superintendent of the 9,762-pupil system in Stafford County, said, "I imagine I'd have to absorb a great many of (Quantico's students). I don't know what impact (possible school closings) may have on us. I imagine it means all those children would have to go to some school division and I'm afraid it might be mine."

The Section 6 action came as a surprise to Wright and Chapin. As a result, they said, there have been no proposals to charge tuition to military dependents living on base who would attend county schools if Quantico's schools are closed.

Section 6 schools are a little-known entity, said Education's Michalkewicz. They are created when states or localities prohibit the spending of their funds for a free public education for military dependents, or when the secretary of education deems the existing public school system unsuitable.

The department has been trying to phase out the Section 6 schools by turning them over to local public school systems whenever possible, she said. "But I don't know how much of an effort we've made of that recently," she added.

The department "inherited" the Quantico system in 1952, when the impact aid program began, she said. There was an unsuccessful effort to turn Quantico High School over to Prince William County in 1955, but the Marines opposed the move, she said.

As a result of that opposition, there is a law prohibiting the transfer of Section 6 schools to local school systems until the secretaries of education and the military branch involved give their consent.

Quantico's superintendent Harcharek said he is confident the base's schools will open on time this fall. A veteran of 23 years in New York state public schools, he said, "Quantico has a tremendous reputation and as a result of that, people are constantly vying to become members of the professional staff."

Only about a quarter of the systems's 95 teachers are married to Marines stationed at Quantico. "Our reputation is based on the quality of our programs and teachers," Harcharek said. "If you have a constant turnover (of teachers), you aren't going to have that.

"We also have a fantastic cluster of substitutes" as a result of the many teachers whose spouses are temporarily assigned to the base, Harcharek added. Their experiences from worldwide traveling and teaching at different bases where their spouses were assigned enhance Quantico's program, he said.

The base's school system, accredited by the state, has a pupil-teacher ratio of about 20 to 1. It spends roughly $3,200 per pupil and sends 74 percent of its seniors to college. In addition, college board exam scores -- 484 in verbal and 504 in math -- have averaged higher than in neighboring jurisdictions and exceed the state and national averages, Harcharek said.

"Quantico is a very disciplined school. . . .It also has a very flexible school body. The average student has a little better background, is a little more attuned," he said. ". . . The public schools didn't match this."