Beginning today, residents in the lower part of Montgomery County must start recycling newspapers or face fines of $50 under a mandatory program imposed by County Executive Charles W. Gilchrist.

The program will expand the life of the landfill on Southlawn Lane in Rockville by at least six months.

Among the areas affected are Bethesda, Silver Spring, Potomac, parts of Rockville, Wheaton and Kensington.

Montgomery's recylcing effort should "enable us to reduce the burden we're placing on our resources to bury this material," Gilchrist said in a press conference overlooking the landfill.

County planners expect the program to recover about 10,400 tons of paper from the 68,000 homes involved. Businesses are not affected.

In a letter, Gilchrist said, "One ton of newspaper converted into insulation can conserve up to 1,000 gallons of fuel oil, 15,000 cubic feet of natural gas, or 13 tons of coal used each year in an average insulated home.

"Yet, less than 20 percent of the waste newspaper is recycled in a nation which generates 70 million tons a year. Most of the paper we discard is either burned or dumped into already overburdened landfills."

As an added benefit, the recycling program will provide 40 jobs in the community, all of which will be filled by handicapped workers. Newspapers collection will be undertaken by National Recovery Industry Inc., a non-profit organization that provides employment for the handicapped.

Only eight of the 40 new collection jobs are now filled by the handicapped, but the number should increase after about three months of recruitment and training NRI spokesman Ramond Jordan said.

Montgomery has had a voluntary recycling program since 1973, but "until now, it's been purely a losing deal," said county Department of Environmental Protection spokesman Chris Capper.

Under the mandatory plan, residents must separate old newspapers from their other garbage, tie them together in 12-inch stacks and leave them outside for separate pickup once a week, on the same day garbage is collected.

The county will monitor homes to ensure trash is being separated and will enforce the program with a $50 fine, Gilchrist said.

A county pamphlet explaining the recycling program stressed that anyone who has been giving his newspapers to a charitable organization or personally disposing of them to a dealer may continue to do so.

No magazines, telephone directories or other paper products with glossy covers should be included with the newspapers, the pamphlet said.

The costs of collecting the newspapers will be roughly balanced by money received for it, Gilchrist said.

The county contracted for five years to sell the papers to the Mason-Dixon Recycling Corp., which supplied recycled newsprint to The Washington Post and The Washington Star.

Mason-Dixon will pay $30 a ton for Montgomery's newspapers, which it will transport to its recycling mill in Garfield, N.J.

Gilchrist said some local firms bid for the contract, but Mason-Dixon offered the county the best package.

Asked how residents will receive a program of recycling by degree, Gilchrist said, "We have already begun to receive some complaints. But the level has been quite low. My assessment is there won't be substantial problems."

Anyone who has questions about the mandatory recycling program should call 762-0840, Gilchrist said.