Prince George's school superintendent Edward J. Feeney opened the county budget season last week by proposing to spend $293.6 million on county schools in 1981-82. Inflation has swollen the school budget by $6.5 million over 1979-80, despite savings expected from a projected enrollment decline of from 122,000 to 116,000 students next year and the departure of 350 teachers and administrators who will not be replaced. The proposed budget does not include funds to cover any increase in teacher salaries under a new contract currently being negotiated.

The budget, several months in preparation, is considered a framework that may be altered considerably by a variety of forces including the teachers' union, the school board, County Executive Lawrence J. Hogan and ultimately the County Council. The teachers' union has asked for a 42.4 percent salary increase.

The school budget represented more than 60 percent of all county spending last year.

School spokesman Brian Porter said the budget contains no program cuts and no additions, except for a small pay raise for substitute teachers, an increase in funding for tuition of handicapped students in nonpublic schools and a $75,000 increase in funds for athletic programs. The increase for athletics will return these programs to fiscal 1979-80 levels.

Feeney said the school system faces a "crisis" in its struggle to live within a TRIM-imposed budget and maintain "instructional integrity." TRIM is the county's tax-limiting charter amendment.

Tonight Feeney will unveil the outline of a plan to close up to 30 elementary schools in the next five years. School budget director George E. Ridler estimates that each school closed would save the system $140,000, barely offsetting the rise in other costs.

Ninety percent of the increase in budget comes from increased cost of employe benefits, mostly health care and Social Security contributions. Much of the health care increases, including hospitalization, dental and visual care, are the result of underfunding of the system's self-insured plan in this year's budget and unusually high claims in 1980.

"In fiscal year, 1981 we are going to run behind, that is we have costs over and above what we provided for in this year's budget," said Ridler.

Ridler said that a cutback in state funding of Social Security will also cost the county $800,000 next year.

The $5.6 million increase in these benefit costs, the $1.2 million rise in motor vehicle costs and other unavoidable fixed costs more than wiped out a $2 million saving in salaries. The motor vehicle increase is blamed on an expected 25 percent hike in the cost of gasoline.

The proposed budget passes only $1.4 million of the $6.5 million rise on to Prince George's County taxpayers. The remainder will come from money unspent last year, mostly unexpected interest earned on school funds this year due to high interest rates, and other projected increases in state and federal aid. The school system normally begins each fiscal year with a surplus fund balance that is applied to the new budget. e

Of the $293 million total budget, Prince George's County will pay $172 million (59 percent), the state $99 million (34 percent), the federal government $13 million (4 percent), with the school system's fees and this year's surplus covering $8 million (3 percent). The percentages are unchanged from the current year's budget.

But the cost of my teacher settlement will have to come from the county, or out of the programs proposed in the budget. Porter estimated that the teachers' original salary demand would cost $93 million.