Five years ago, engineers at International Business Machines Corp.'s semiconductor manufacturing plant in Manassas discovered that two of their underground storage tanks holding hazardous waste chemicals had sprung leaks.

Cleaning up the mess and refurbishing the storage facility with double-walled tanks to prevent a repeat of the accident cost IBM millions of dollars and a brush with the Environmental Protection Agency. But Robert Estabrooke, manager of site support at the Manassas plant said: "The added expense of putting in double-walled tanks easily outweighs the costs of having a release of waste into the environment. ... We now know we're not going to have another surprise."

IBM isn't the only company in the area taking hazardous waste very seriously. With the recent dramatic growth in high-tech manufacturing around Washington, more local firms have been forced to respond to the tough federal and state laws of the past 10 years that govern the disposal and treatment of hazardous wastes, as well as respond to a legal and public climate increasingly unforgiving to polluters.

A number of Washington area firms are taking innovative approaches to the waste management problem by recyling what used to be thrown out or by simply changing manufacturing processes to produce less waste.

Through the Resource Conservation and Recovery Act, implemented in 1980, and the so-called Superfund amendments of 1986, Congress broadened the definition of hazardous waste. It has also instituted, along with the states, an elaborate tracking and permit system covering everyone who generators, transports, stores or disposes of wastes. And, for the first time, it has made companies legally responsible for any environmental damage caused by waste from the moment they produce it until the moment it is destroyed.

At the same time, Congress is putting the squeeze on the practice of pouring waste into drums and burying it in landfill sites, long the most common and least expensive form of waste disposal. Over the next 2 1/2 years, 56,000 companies across the country will be required by the EPA to take some 570 billion pounds of waste elsewhere.

"The old days of sending hazardous waste out to the landfill or putting it down the sewer are gone," said Tony DiPasquale, a spokesman at E-Systems Inc.'s Melpar division in Falls Church. "Disposing of materials can now be as expensive as buying them in the first place."

With the cost of disposing of hazardous waste increasing sharply, companies are opting more and more to simply minimize the amount of waste they generate. According to a recent Office of Technology Assessment study, up to 50 percent of all industrial wastes can be reduced economically.

"The most cost-effective way of dealing with hazardous waste is not to generate it," said Mike Young, chief environmental officer at Atlantic Research Corp. in Fairfax.

Atlantic Research has installed a distillation system at its Alexandria plant that purifies solvents used in cleaning metal parts for reuse. That, along with a campaign to substitute ordinary soap and water for chemical cleansers whenever possible, has cut the amount of waste the plant generates to two drums a year from 15 drums.

A similar program at ARC's main rocket engine plant in Arkansas has saved the company tens of thousands of dollars, according to Young, and paid for itself in four months.

"The new regulations have made disposal much more costly, but at the same time, it has helped the company handle its waste more efficiently and intelligently," Young said.

IBM has a similar solvent recyling system in operation in Manassas, along with a water treatment system that cleans the acidic and alkaline rinses used in semiconductor manufacture.

But the most impressive local recyling effort is probably at Du Pont Co.'s paint plant in Front Royal, where company officials say they have a distillation system twice as effective as the industry norm. It has enabled them over the past two years to cut in half their generation of waste solvents used as paint bases or cleansers.

"Waste minimization is a top priority here," said Warren Miller, an environmental specialist at the Front Royal facility. By 1990, Du Pont officials say they hope to cut generation of all kinds of wastes by 35 percent from where it stood in 1982.

Still, the evidence is that American companies have been slow to capitalize on the economic benefits of waste reduction.

Inform Inc., an environmental research organization based in New York, studied 29 major American organic chemical plants in 1985 and found only 44 examples of waste reduction at the source, accounting for less than 1 percent of the wastes generated by the plants.

Part of the problem, government officials say, is that some businesses simply aren't aware of the potential of technologies to cut down waste generation.

As a result, both Maryland and Virginia are working with the EPA to provide data bases on waste minimization for interested businesses.

Maryland also is a partner with 13 other states in the six-year-old Northeast Industrial Waste Exchange, a Syracuse, N.Y.-based self-styled "dating service" that attempts to match up waste generators and potential recylers.

In the Washington area, the problem with waste disposal is particularly acute, experts say, because so many of the local waste generators are small start-up companies with limited resources.

Automata Inc. a Reston-based manufacturer of computer circuit boards, has a comprehensive water treatment system that turns water contaminated with heavy metals into a recycleable sludge. But the equipment required a $500,000 investment.

"The net effect of all this is that you've got to throw a lot more manpower at the problem," said Young at Atlantic Research. "In a company like ours that has the resources, that's not a problem. But it might be among smaller companies."