THE JUSTICE Department went to court this week seeking an injunction to stop 12 chemical and oil companies from unloading any further chemical wastes into two dumps the government believes pose an imminent danger to public health and the environment. Previous suits have been filed against the operators of dump sites, but this is the first time the government has been able to collect sufficient evidence to include the companies that are actually generating the wastes.

At least one of the companies will defend themselves by arguing that "at the time we used the site, it was an acceptable way of doing things," but this defense is unlikely to hold up. Those engaged in what the law calls "ultrahazardous" activities are held liable for dangers that may result. Moreover, one of the two sites is in a swamp that periodically floods, and it should be difficult to persuade any judge that this was ever an accepted way to dispose of hazardous wastes.

The suite indicates encouraging progress in efforts to bring the improper disposal of hazardous wastes under some kind of control. But it also serves to emphasize the many remaining deficiencies in the legal tools the government has at its disposal. If, for example, the government wins this suit, which is in Louisana, it can compel the companies to bear the expense of cleaning up the site, but the law that governs hazardous waste disposal does not provide for the imposition of any fines or other penalties -- even against the companies that dumped their waste on the swampy flood plain.

Nor can the government sue on behalf of third parties -- local citizens and landowners whose health or livelihood has been damaged by the leaking chemicals. In order to collect any damages from the companies, these individuals must take their chances in local courts -- governed by state law that varies from state to state -- where they may not be able to make use of the evidence established by the government in federal court.

Even if the government could prove in a particular instance that company officials knowingly approved waste disposal practices that would severely damage public health, the government could not now bring criminal charges against those individuals. This would be true even if those actions threatened the lives of innocent people as surely as do the decisions of a hit-and-run driver. l

Bills that would fill all these needs are pending in Congress. Prompt action on them would strengthen the government's ability to stop dangerous practices and compel companies to clean up the messes they have created without having to take each case to court. There may be 1,000 or more dangerous waste sites scattered around the country -- and not even Washington has enough lawyers to tackle efficiently that big a problem through slow and expensive litigation.