CONSIDER one week's harvest of news stories:

-- Just a few days of dumping untreated sewage may have made the southern end of San Francisco Bay (until now a productive shrimp fishery and bird refuge) uninhabitable for both fish and birds for years.

-- The Food and Drug Administration confirms that small amounts of carcinogenic chemicals are present in many brands of beer and Scotch.

-- The governor of Arizona resorts to using the National Guard to shut down a plant that has been leaking radioactive tritium.

-- Nineteen states find food and animals contaminated with the suspected carcinogens known as polychlorinated biphenyls (PCBS) -- all tracing back to a single leaking transformer.

-- The chief of Michigan's environmental enforcement agency says that "chemical contamination may be so widespread and pervasive . . . that it's to the point where we may find it cheaper to simply write off the groundwater supplies of large portions of southern Michigan."

Such stories are, in a strange way, page-turners, seeming never quite real, never quite plausible, never quite conclusive. They describe things that sooner or later may happen to someone else. But let's stop to consider just one -- the Michigan story. What can it mean to write off the groundwater supply? What are the citizens of Michigan to use for water? Is it to be club soda in the washing machine? Maybe not, but the options aren't much more attractive. Either the money has to be found to clean up the water, or an alternate water supply must be found, or the situation can be ignored and the health costs paid later. Unhappily for Michigan, finding large, heretofore unusued supplies of water is not so easy, and, as more and more communities are discovering, the cost of cleaning up contaminated resources -- air, land and water -- is enormous. In fact, the cost is generally prohibitive for all but the already overstrained federal budget.

The Love Canal disaster gives some measure of the relative dimensions of these costs. Approximately 1,000 claims for personal and property damage against the city of Niagara Falls, the state of New York and various other parties have been filed. They total over $2 billion. Millions have already been spent for short-term containment of the leaking chemicals, and the cost of final, long-term disposal will be far greater. However, if the chemicals that caused all this trouble had been properly disposed of to begin with -- with all necessary precautions taken against leakage -- the cost would have been no more than about $4 million.

Given today's population density and level of industrial activity, threats to crucial resources and human health seem to be multiplying at an unprecedented rate. In relation to some resources in the United States -- perhaps including our water supply -- we may be treading on the margins of what nature can tolerate. A small mistake, such as the sewage plant failure in San Francisco, pushes the system over the brink.

The evil of too much government regulation has long since become a cliche. A public opinion poll taken last spring concluded that more than half of the public believes that the costs of government regulation are greater than the benefits. The irony is that the facts seem to indicate something different: inadequate and mishandled regulation is doing terrible harm. Instead of returning health and safety concerns to the uncertain care of "market forces," what the country seems to need in these particular fields is better -- and in some cases, new and tougher -- government regulation.