THIS WEEK the Environmental Protection Agency issued a mammoth set of regulations that are the country's first attempt systematically to control the disposal of its hazardous wastes. The product of more than three years' work, the regulations set in motion a process that will provide -- in the words of EPA Administrator Douglas Costle -- the first hard facts about "a problem whose dimensions we now can only guess." This information about the sloppy, and in some cases grossly negligent, ways in which these wastes have been handled until now will, he predicts, "shock our nation."

After the events at Love Canal in New York and just the other day at Chemical Control (which blew up) in New Jersey, and given the Houston, Tex., company that conveniently disposed of deadly cyanide and nitrobenzene by mixing them with oil used to surface rural dirt roads, it is hard to imagine what could be shocking. But EPA and the state agencies do have a gigantic catch-up effort ahead of them, and as the new system uncovers more and more past abuses, the problem will probably appear to get worse before it gets better.

Inevitably, the EPA regulations were attacked from all sides as soon as they were published. Industry complained that the costs of compliance will be higher than EPA estimates, and that some of the standards are too tough. Some environmentalists think they are too lax. Their chief complaint is that EPA chose to exempt small producers -- those who produce less than a certain amount of wastes each month -- from the regulations.

These critics argue that the exemption -- made in the name of practicality and an attempt to balance administrative costs against risk -- is not legal under the law Congress wrote.While this may turn out to be true, EPA made a wise and sensible choice. It chose not to jeopardize the entire program by biting off, at the start, more than it could chew. It avoided getting itself bogged down in the paper work and bureaucratic nit-picking that have weakened so many other health and safety programs that were rushed into action without any sense of priorities or relative risk. It chose to focus on the 10 percent of waste producers who generate 90 percent of the waste, and to leave aside -- at least until the program is well established -- the much larger number of small producers.

As for industry's worries, regulation should never cost more than it has to, but it seems in this case that EPA has made an honest effort to keep the paper work under control. And, regardless of whether the costs of compliance turn out to be higher or lower than the estimates, they will certainly be much less than the costs of cleaning up improperly disposed of wastes. For example, it will cost at least 100 times as much to repair the damage at Love Canal as it would have cost to dispose of the chemicals properly in the first place, and that is a typical figure.

These regulations are only the first step in what will be a long, technically difficult, politically contentious, expensive, but vital process. Much will depend on the actual technical standards that will not be issued until next fall. Some mistakes may already have been made -- certain chemicals, for example, may have been wrongly left off the regulated list. But all in all, EPA's decisions so far, though very slow in coming, appeart to represent a model of a mature, cost-conscious but vigilant regulatory effort.