The 4,000 Cuban refugees expected to settle in Maryland could cost the state government $1.2 million in financial assistance if the Carter administration's one-year relief program is approved by Congress.

More than half of the refugees -- 2,500 -- are expected to settle in Montgomery and Prince George's counties, according to sources in the Spanish-speaking community. As many as 500 families are expected in Montgomery County alone.

Maryland officials criticized the plan, announced by the State Department last week, which would leave 25 percent of the resettlement cost of Cuban and Haitian refugees to state and local governments. An estimated 114,000 Cubans and Haitians have immigrated to the United States.

In Maryland, the state will cover almost all of the costs not paid for by the federal government. The strain on local resources will be felt by county welfare workers who will be required to process the new arrivals, according to a Montgomery official.

"If I invite you to dinner you'd expect me to pay for it," said Frank Bien, the Maryland coordinator for refugee affairs. "The federal government decided to allow these people in and it should provide the funds for them."

Rep. Michael Barnes (D-Montgomery), a member of a congressional committee that will review the Carter proposal, said, "It's sad to see the burden placed on local governments when federal policy led to this situation."

Volunteer groups have been in daily contact with the Florida and Indiantown Gap, Pa., refugee camps trying to determine exactly how many refugees will settle in the state. In an effort to get an accurate count, Montgomery County Executive Charles Gilchrist plans to visit the Indiantown Gap camp July 2.

Montgomery's local services could be severely strained by a large influx of refugees, according to Gilchrist. But the county executive said the refugee plan proposed by the Carter administration showed a "definite federal concern."

"We have to avoid pointing fingers at who's responsbile. The Cubans are here, and now we've got to come up with ways to provide the services they need," Gilchrist said.

The Carter administration's plan would establish a special "Cuban-Haitian entrants" status for the recent arrivals. The federal government would reimburse state governments for 75 percent of resettlement assistance. The aid would only be given to refugees now in the United States and the plan will end after one year.

Under the Refugee Act of 1980, the federal government pays all the costs of settlement of refugees for three years after they arrive. Carter's special status plan would remove Cuban and Haitian refugees from coverage by the act. s

There is no estimate on the number of Haitians who might settle in Maryland.

Congress is not expected to review the proposal unitl next year. In the meantime, state and local governments must supply assistance with the promise of partial reimbursement from Washington.

Prince George's County Council member Francis B. Francois called the plan "a totally inappropriate response to the refugee issue.

"State and local governments have to pay now and hope that they might be reimbursed some day. That simply won't work." Francois is head of the National Association of Counties, which strongly opposes the Carter proposal.

The federal Department of Health and Human Services estimated that Maryland will spend an average of $300 on each refugee for welfare-related assistance, based on similar costs under the Indochinese refugee program. Each refugee coming into the country costs an average of $1,200 in government funds, an agency spokesman said.

Maryland's share of refugee assistance will be higher than 25 percent for some of the Cubans, according to a National Association of Counties spokesman. One primary welfare program -- Aid to Families With Dependent Children -- will be handled under normal federal-state matching grants. Maryland will pick up 50 percent of the cost for Cubans in its AFDC program.

About 140 Cuban refugees have already arrived in Montgomery County and another 120 have entered Prince George's, according to spokesmen form the volunteer groups working with the refugees.

Community organization spokesmen said they are pleased at the prospect of any federal assistance. Under the Carter plan, they will recieve $300 for each Cuban or Haitian entrant. However, if full refugee status had been granted the groups would receive $500 per person.

A month ago, only 50 to 60 refugees were processed out of the camps each day, volunteer workers said. Now about 500 leave each day and volunteer agencies expressed concern about getting swamped if they do not receive federal support.

Emilio Rivas, director of the Spanish-speaking Community of Maryland, headquartered in Silver Spring, said state and local governments should be willing to share the cost of resettlement.

"President Carter is doing everything he can to help. The cost should be shared because the refugees will be contributing their taxes to communities once they settle," Rivas said.

A spokesman for the U.S. Catholic Conference, one of the nation's largest voluntary agencies, criticized those who put a community's economy above aid to the refugees.

"These people haven't asked for special treatment," said Hang Dorsey. "All they're looking for is a landlord to be kind enough to give them a place to stay and an employer to give them a job so they can get a good start in the community. They apply for jobs most people don't want, they work hard and they hold their jobs."

Most of the Cubans are expected to settle where there is already a large Cuban population. Maryland has an Hispanic pouplation of about 74,000, the fifteenth largest among the states.

About 6,000 Cubans live in Montgomery County and 4,000 in Prince George's. There are significant Hispanic pouplations in Silver Spring, Tacoma, Langley Park, College Park Bethesda and Baltimore.