In a massive depletion of the top ranks, more than 40 high-level D.C. police and fire department officials -- most of them white -- will retire at the end of the month, spurred by a combination of higher retirement pay and long-brewing disgruntlement with the city's black administration.

The retirements mark the largest single exodus of assistant chiefs, deputy chiefs and various midlevel supervisors in the recent history of either department. This could create at least a partial vacuum of expertise and long-term experience at some levels.

The retirements will also make way for promotion of more blacks into supervisory positions, although that process may be slowed -- especially in the police department -- by internal reorganization, consolidation and other cost-cutting efforts being considered by the financially strapped city.

The immediate effect, however, is that five of the police department's 12 deputy chiefs and seven of its 21 inspectors are expected to be gone by Aug. 31, leaving a lack of seasoned leadership in such crucial areas as communications, criminal investigations (detectives) and special operations including the riot-trained Civil Distrubance Unit. Several civilian employes, including the department's chief expert on latent fingerprints and its specialist in handwriting and forged documents, are also leaving.

The situation is even more bleak in the fire department. Both assistant chiefs are scheduled to retire, as are three of the six deputy chiefs and 16 of the department's 33 battalion chiefs.

At the very top of both departments, Fire Chief Norman Richardson and Police Chief Burtell M. Jefferson do not appear to be heading or immediate retirement, but Jefferson hinted recently he may leave before the end of the year.

In addition to the more than 40 top officials retiring, nearly 150 rank-and-file officers -- detectives, patrolmen, technicians, fireboat pilots and other specialists -- plan to retire by Aug. 31. Each has served at least 20 years in the fire or police department. aSome have served 30 years.

On top of that, as many as another 341 police officers and firefighters could retire under a new law recently approved by the City Council that would permit them to quit their jobs on reduce pensions after at least 18 years' service in the police or fire department. It is not immediately known how many officers or firefighters will take advantage of the provision, but some have already announced their intention to retire.

The retirements are being triggered in part by a federal law that gives retirees two cost-of-living raises totaling nearly 14 percent of their pensions. These raises can be tacked on to their annuities if they retire by Aug. 31. Many find the 14 percent sweetener irresistible. They will join thousands of federal and District government employes retiring for the same reason.

But many police and fire officials give another reason for leaving: as whites, they say they have no future, and are being boxed out of the promotional track and policy-making apparatus of their departments by a City Hall administration committed to accelaterating black promotions in the traditionally white-dominated uniformed agencies of the government.

"A lot of guys feel it's a racial thing, and you can't get ahead," says a white lieutenant.

Other officers, who, like the lieutentant, asked not to be named, say high-ranking whites are often ignored or left out of important conferences and staff meetings with City Hall officials.

One high-ranking white official said the rapid rise of relatively inexperienced blacks into supervisory positions has shorn the department of its "institutional memory."

"The [blacks] ignore a lot of the departmental procedures," he said. " . . . They don't [provide feedback at lower levels on ] headquarters' requests. They don't route memos to the right people. The don't acknowledge receipt of reports."

"There's less direction and purpose, " says another official.

In addition to the complaints of old-line whites, there are long-standing internal problems -- budget cuts uncertainty about pay raises and layoffs, a perceived loss of respect in the community -- that have bruised the morale of both black and white officers, and apparently have hastened the retirement of many at the lower levels of the department.

More officers are retiring immediately on completion of 20 years' service -- the shortest period to qualify for retirement benefits, and are seeking second-career jobs to keep up with inflation.

Many officers say there has been little apparent effort by Chief Jefferson to groom new commanders to replace retiring officials in key areas, such as criminal investigations and special operations.

They said the quality of detective work on homicides, robberies and white-collar crim e may deteriorate, along with the discipline of the Special Operations Division, whose elite units handle everything from hostage situations to crowd control at political demonstrations.

In the case of the Special Operations Division, its longtime commander, Deputy Chief Robert W. Klotz, is retiring, and so are two of his top assistants.

Police Chief Jefferson brushes aside the criticisms. Promotions of skilled commanders to key spots will come in time, he said, but not before Mayor Barry approves a still undisclosed "realignment" proposal Jefferson submitted the proposal last week. It apparently contains suggestions for consolidating or dismantling parts of the department to reduce the number of midlevel commanders.

For the moment, Jefferson said, "We can operate without any difficulty. I don't expect any problems. We have trained the men in management processes and [have given them] inservice programs with the idea of upward mobility. This is not a case where the department is going to fall to pieces."

On the question of black-versus-white promotions, Jefferson noted that all promotions above captain -- that is, to inspector, deputy chief and assistant chief -- are up to the discretion of the chief and the mayor.Promotions to sergeant, lieutenant and captain are based on competitive examinations.

"I have always made [discretionary] promotions on the basis of ability, not race," he said.

In fact, he added, most of those promoted continue to be white because the middle levels of the police department are still predominantly white.

One high-ranking black official said privately that Jefferson's closet departmental advisers are largely black because he is personally more comfortable with them -- "just like a white chief would be with white advisers."

There are 45 captains on the 3,900-member police force. The majority are white. They will be vying for seven inspectors' positions which will become vacant soon.

The seven inspectors planning to leave are white. Of the 14 inspectors who will remain, seven are white, seven black.

They will vie for five deputy chief positions which will open up soon because of retirement. Four of the five deputy chiefs leaving are white. Of the seven deputy chiefs staying, three are white and four are black.

They will be completing to become assistants chiefs when any of the four incumbents retires. None of the assistant chiefs -- two blacks, two white -- has indicated when he might leave.

The police force is about 45 percent black. It has been in the 40-percent range for nearly a decade, moving a steady flow of rank-and-file black officers into the promotion pipeline.

The 1,400-member Fire Department is about 32 percent black. The top echelons are overwhelmingly white. A few blacks, including Chief Richardson, have gone to the top in a relatively short time, which has made many whites bitter.

This is how the month's mass retirements have affected the fire department's promotion picture.

Sixteen battalion chiefs -- all but one of them white -- are retiring. That will leave 17 battalion chiefs -- all but one of them white -- still in the department. Those 17 will vie for three deputy chiefs slots opening up because of retirements. The deputy chiefs leaving are white.

The three deputy chiefs staying are black.

Those three will compete for the two assistant chief positions which are being vacated. One of the assistant chiefs leaving is white; the other is black.

The federal law under which these officials and dozens of other police and fire department employes hope to retire is being challenged in Congress. Some House members are trying to trim the cost-of-living raises added to the pensions. They consider these raises overly generous.

The issue is expected to be resolved later this month.

Jefferson -- who joined the police force in 1948 and spent 30 years working his way up to the chief's office -- hinted in a recent interview that he may quit before the end of the year.

"I'm not going to stay here forever," he said. ". . . If I leave the department, they can find a suitable chief to take my place."

Asked if he planned to stay for the presidential inauguration in January -- an elaborate event in which the District police chief is a major ceremonial figure -- Jefferson said: "Why should I?"