STATEMENT SUBMITTED TO THE SUBCOMMITTEE ON SCIENCE, RESEARCH, AND DEVELOPMENT BY RAY K. LINSLEY, EXECUTIVE HEAD, DEPARTMENT OF CIVIL ENGINEERING, STANFORD UNIVERSITY, AUGUST 3, 1966. (ORIGINALLY SCHEDULED TO TESTIFY; UNABLE TO Do So DUE TO AIRLINE STRIKE)

I am pleased that I have been invited to come here and discuss with you the question of the adequacy of technology for pollution abatement. It is such an all-encompassing subject that it is hard to know where to begin and what to say in a limited time. My problem is made no easier by the very excellent report of your research management advisory planel which has discussed the subject wisely and well. A few weeks ago, in testimony before the Senate Committee on Interior and Insular Affairs, I suggested that one of our problems in looking at water today is that we are in a period of rapid transition. After centuries of slow change, we now find it difficult to realize that very major shifts in thinking are necessary. Unlike many other scientific and technological developments which have come upon us in a very short time, pollution problems have been developing very slowly for a long time. Our fundamental approach to the pollution problem is as ancient as man himself. Man started to pollute the atmosphere when he first learned to make fire. He piled his solid waste in great heaps which today, all over the world, mark the location of his ancient cities. He found that water was a very convenient medium for carrying away his wastes, and he learned to wash all manner of things in a stream. Ancient man could successfully employ these rather crude means of waste disposal because of his own very limited numbers. The quantity of waste produced was relatively small compared to the assimilative capacity of the environment. Today, when the annual population increase of the world exceeds the total population at the time of ancient man, the situation is quite different. Not only are there more people producing waste, but the per capita production is greater. In addition, our technology is producing substances which, when they become waste, are more durable than much of the organic waste of ancient man.

Sewers to transport storm water from cities date back into antiquity. Because of the prevailing practice of throwing refuse into the streets these sewers carried at least some of the waste washed into them by rain. It is only a little more than 100 years ago that direct sanitary connections to sewers were begun in major cities. These connections together with a system of refuse collection removed the waste from its highly visible location in the streets and considerably augmented stream pollution. As stream pollution got worse, plants for partially treating the sewage were designed to reduce the pollution load on the streams. Today we find that in areas of high population density the partial treatment of waste is not always adequate. We are also beginning to realize that we can ill afford to use so much water to dispose of this waste.

What I have just said can be restated to say that we are beginning to realize that we have a complicated system on our hands. Burning solid waste adds to air pollution as do the gases emitted in sewage treatment. Sewage may destroy the usefulness of a water supply. The automobile, a transportation device, is a major source of air pollution. Irrigated agriculture adds salts to the rivers. Pollution management clearly requires more than the concept of "put it where it won't be seen". We must study all our activities in the light of their total impact on the environment.

Science has a principle called conservation of matter. In essence, this states that matter cannot be destroyed. It may be converted into other forms, but its essential elements remain. We would not be far wrong if we drew from this a principle of conservation of pollution which said that waste materials, once produced, are with us always. With the exception of that relatively small fraction of waste materials which man reclaims for his own use and the portion of the waste materials which are converted by natural processes into useful material, the principle of conservation of pollution is essentially valid. When man burns solid waste, he does not eliminate it, he merely converts it to gases and particulate matter which may pollute the atmosphere. If we dump pollutants in the ocean, we are not eliminating them, we are simply putting them where we cannot see them. Conventional sewage treatment removes a portion of the pollutants from the water being treated, but these pollutants are not destroyed. In part, they are converted to less obnoxious gaseous or liquid forms which are discharged through the atmosphere or to a water body. In part, they remain as solids which must be "disposed of" in some way. When we bury solid waste in a sanitary land fill, it disappears from view, but it is still there. Water moving through the fill may leach material from the waste and carry it to the ground water or to another stream for years after the original disposal.

A few cities are now requiring every home to have a garbage grinder. This greatly eases their problem of garbage collection, but at the expense of increasing the magnitude of their sewage treatment problem. Solid waste is being changed to stream pollution. This may indeed be the most economic solution for the individual city, but what of the cities downriver whose water is more polluted? Applying salt is an effective means of snow removal from roads and streets, but melting snow and rain must eventually carry this salt to a stream or the ground water.

It is probably true that conventional means of dealing with pollution could, if pursued with vigor and sufficient funds, provide a short term solution to our problem. That is to say, a substantial investment in present technology might alleviate our problems for a few years. Not only would the expenditure be very large, perhaps more than we can really afford to pay, but such an approach might have another most undesirable effect. It could lull us into believing that we have the situation in hand, as we have been lulled in the immediate past. If this led to a failure to prosecute an effective research program on new technology, we would eventually find ourselves in a position which is even worse than our present one, but with nothing better by way of a solution. It is interesting to speculate where we might be today if we had recognized the environmental pollution problem in 1946 and

had started to work on it at a rate of 10 percent of our expenditures on space research.

I have described our problem as a systems problem. Let me hasten to say that I do not suggest that this is the sort of systems problem that can be written down in mathematical expressions and answers derived in a few minutes or even a few hours time on a computer. I say this for two reasons. First, and foremost, we simply do not know enough about our problem to write the necessary expressions. Secondly, if we could write the necessary equations, there is every reason to believe that we do not have today a computer big enough to solve them. But a systems problem does not have to be solved by a mathematical equation and a computer. Basically, a systems analysis requires that we know something about the goals which we are striving for, and the capabilities and costs of solutions which would contribute to these goals. With systems analysis techniques, we would then seek to find the optimum combination of solutions for the attainment of our stated goals. Systems analysis requires an orderly, but not necessarily mathematical approach, to a problem.

If we wish to approach the pollution system realistically, we must do several things. These are:

(1) Define with reasonable accuracy the sources and quantities of pollutants now and estimate these data for future years. (2) Identify the effects of these pollutants on man.

(3) Define with considerable clarity our goals for pollution abatement.

(4) Describe the technically feasible methods of dealing with each major pollution source with reasonable cost estimates.

(5) On the basis of the foregoing information, determine the most efficient combination of methods to deal with the problem. There is little hope that we can or will deal with the total environmental pollution problem as a single systems analysis problem. It is too big and would take too long. Indeed, it may never be fully solved. New sources of pollution will develop. New abatement techniques will be found. The details of the problem will shift continuously. However, if we approach the problem systematically, we can hope that our efforts will yield the maximum possible achievement.

Pollution is the sum total of many different substances from many sources. The need for an inventory of these substances seems obvious. yet I know of no such inventory. Some pollutants are more harmful than others; some are easier to deal with. With a reasonably accurate inventory as a start we can begin to identify those substances and sources for which abatement offers the most immediate payoff. Because we are planning for the future we need estimates of future pollution sources and substances. Most important are some educated guesses at which substances, now nonexistent or unimportant, might be problems in the future. The problems which can be recognized in advance may never become problems. The inventory would seem to be a responsibility of the Federal Government and one which should proceed as rapidly as possible. In a sense it parallels the inventory responsibility of the Federal Water Resources Council, but the pollution inventory is a much more complex job than a water supply and demand inventory.

Item 2 of my list requires definition of the effects of various pollutants on man. This includes direct physical effects on health, eco