Post readers should regard as an insult to their intelligence the series of quarter-page ads on acid rain, which have appeared over the past few weeks under the auspices of the self-anointed "Coalition for Environmental-Energy Balance." The ads castigate the commendable Mitchell-Stafford acid rain bill--which reasonably limits itself to the eastern states where the problem is most acute, and to sulfur dioxide emissions by utilities that are the dominant source of the problem--on the basis that the acid rain problem "is worldwide in scope" and "cannot be viewed in the narrow perspective of a single community, state, region or nation." Under such perverse logic, the more widespread a problem, the less any governmental body should seek to do about it.

The ads also assert that "almost all rain is acidic and that in some cases it is beneficial." The coalition would have us believe that the scientific evidence that the role of acid rain as a serious environmental problem (e.g., the cause of "dying" lakes) is a matter of great uncertainty and "circumstantial evidence" on which honest men can disagree. Absent a "smoking gun," as the ads put it, the Mitchell-Stafford bill is said to be "a rush to judgment" and a matter of "overreaction and overregulation."

Nothing could be further from the truth. In fact, as a report released in September by the National Academy of Sciences has reaffirmed, the evidence linking power plant emissions to acid rain is "overwhelming." It emphasizes that without controls on emissions of sulfur and nitrogen oxides from fossil fuels, a more than doubling of the number of affected lakes can be expected by 1990.

The NAS report also finds that any benefit that acid rain may provide to sulfur-or nitrogen-deficient soils would be "short-lived" and that the net long-term effect is "likely" to be decidedly negative. And while it is true that most rains are naturally acidic, unnatural and destructive levels of acidity are becoming more and more common in more and more parts of the United States. Even west of the Mississippi River, an area not usually associated with acid rain, increased rainfall acidity and even incipient signs of damage are being perceived in at least 11 states.

One final contention that cannot be left unchallenged is the ads' claim that the Mitchell-Stafford bill "could mean increases of as much as 50 percent in (the) electric bills" of consumers "in at least three states, Ohio, Indiana and Illinois." In fact, the best available estimates indicate that average utility rates in the 31 eastern states would increase by no more than 2 or 3 percent, with the highest increases--in the range of 6.5 to 8 percent--occurring in Ohio, Indiana, Kentucky, Tennessee and Missouri. Not only are such increases rather moderate, but they quite properly fall on states that are among today's largest emitters of sulfur dioxide. Even after these increases, these states will still enjoy rates lower than those in the mid-Atlantic and New England states.

It is curious that the ads fail to note the multi-billion- dollar cost that not controlling acid rain imposes on our economy and, in particular, on those who rely on the resources damaged by acid rain. In addition to millions of dollars in annual damage to lakes, resorts and recreational fishing, acid rain and its precursors have been linked by some scientists to billions of dollars' worth of annual damage to buildings, construction materials, etc., and, at least potentially, to human health. Damage to crops and forests has been estimated to add further billions to the tally.

Even if the ads were right that acid rain in the United States has not yet assumed "smoking gun" proportions, it is clear beyond doubt that a "pointed gun" is there. The Mitchell-Stafford bill is a laudable effort to point the "gun" away from our heads.