D.C. schools superintendent Floretta McKenzie has proposed a $381.8 million operating budget for the 1986 fiscal year that includes $20 million to remove asbestos from school buildings and $12.5 million in salary increases for teachers and other personnel.

The budget proposal, made public last night at the first hearing on it before the D.C. school board's finance committee, is $42 million higher than the fiscal '85 request now awaiting congressional action, and $55 million higher than the budget for the current fiscal year, which ends Sept. 30.

In addition to the allocations for the asbestos cleanup and salary increases, the proposal includes $10 million in increased expenditures for a variety of programs and services, including $1.7 million to implement a teacher-incentive plan, $1.8 million to pay teachers aides who are now paid through special federal grants and $1.5 million to purchase new buses.

Also included in the $10 million are proposed increases in funding for school security, special-education classes and programs for the gifted and talented, and money to create a museum of the history of D.C. public schools in the Sumner School building.

Last night's hearing was the first step in a long process the proposal must undergo before it reaches final form. There will be a second public hearing before the finance committee tomorrow night, followed by hearings before the full board and the D.C. City Council.

It must then win the approval of Mayor Marion Barry before it can be sent to Congress for final action early next year.

Other items included in the proposal for fiscal '86, which begins Oct. 1, 1985, are an increase of $1.1 million over fiscal '85 in funds for bilingual education programs and $1 million for "underfunded base services," such as graduation ceremonies and other regular activities sponsored by schools that currently are paid for with money not expended on other programs.

School officials said the increases in funding for bilingual programs reflect their belief that schools should do more to accommodate the growing numbers of students who immigrated here recently from Asian and Spanish-speaking countries.

The $20-million allocation for asbestos cleanup is what the board currently estimates it will cost to remove crumbling asbestos -- a cancer-causing substance -- from all 162 schools and administrative buildings in which it has been found. The schools system recently spent about $725,000 from fiscal 1984 funds for "stopgap" measures to enclose the areas most affected by crumbling asbestos and is expected to divert more than $2 million from the 1985 budget to continue the work.

The proposal for teacher salary increases was the second in as many years. The board requested $11.1 million for salary increases for fiscal '85, but Mayor Barry vetoed that request before sending the budget proposal to Capitol Hill.

"We can't ask teachers and staff to go two years in a row without a pay increase . . . " said board member David Hall, chairman of the finance committee.