I can only say that, as a biologist, if emissions of SO2 and NOx are permitted to continue to increase or to stay the same, that we can anticipate a greater effect upon aquatic ecosystems and will increase the probability of important effects on terrestrial ecosystems.

Senator DOMENICI. Doctor, are you familiar with the concept whereby an ambient airshed is regulated by what is called a State implementation plan?

Dr. COWLING. Yes, I am.

Senator DOMENICI. I think the facts are that, for the most part, those conversions that we are now addressing, somewhere between 107 and 91 or 92, can be made without violating State implementation plans.

What does that tell you? What does that mean? Does that mean that we don't have a problem because the State implementation plan is, as a matter of fact, the environmental control mechanism for an ambient airshed and it does address the issue of SO2 and it does address-although many State implementation plans don't even have NO, in it; I guess you know that. Many have not perceived it early on to be enough of a problem.

But it is the legal mechanism.

Dr. COWLING. Yes. The legal mechanism deals with air pollution as a piecemeal matter. You must take up criteria pollutants.

SO2 is one criteria of pollutants; NO, is another. Acid rain is not a criteria of pollutants at the present time.

In the interest of diminishing ground level concentration of SO2 primarily in the interest of protecting health, it has been permitted under the State implementation plans to raise the stacks.

That has had the effect of increasing the long-distance transport of air pollutants and consequent increased amounts of acid rain and acid snow in various regions of the country.

So, I must say, I think it is important that we approach the regulation of air pollution in a comprehensive way and understand the interaction among pollutants.

I have spent some substantial time looking at the criteria documents on SO2 and NO,, and they are written as though the other did not exist. And plants and animals react to both substances in the air.

I think it is sensible that the criteria documents should not be so compartmentalized as to act as though other criteria pollutants did not have important influences on what ought to be done with the one which you are discussing.

Senator DOMENICI. Let me just make one more point and see if you agree with me. First, let me say, I don't know what to do about acid rain and the backout problem because it isn't as simple aswe don't only have one national interest that we are concerned with.

I mean, obviously, we are very concerned about the excessive importation of crude oil. So, this whole bill is premised upon the National Government having not only an interest in abating that, but it is so genuine that we are willing to pay part of the tab for the conversion. That is on the one hand.

On the other hand, there are those who say that, as long as this conversion does not violate a State implementation plan, what is the problem?

Now, am I not correct that the problem is not within the district, the airshed, that the State implementation plan controls because, as a matter of fact, that standard is rather good?

The problem is that we have never addressed the issue of what happens to that pollutant after it leaves that airshed where it started, not in violation of any air standard. But it moves somewhere and then we get the acid rain, another new pollutant in another area.

Is that not the issue that we are confronted with?

Dr. COWLING. Yes, it is, very much. You have your hand on a very important part of this whole dimension. We have developed our approach to air pollution on the assumption that the quality of air in a given State could be controlled by that State.

And the acid rain problem illustrates the long-distance transport problem. It may be impossible for a given State to control the quality of its own air simply because the pollutants do not respect the political boundaries that separate the States.

Senator DOMENICI. That is not to say that the State implementation plans and the mechanism in the Clean Air Act is not a good one. We are merely saying we are learning substantially more about the mobility of these kinds of molecules, and they move very, very far.

And we have not attempted to address that issue in the Clean Air Act to this point.

Dr. COWLING. No. I think that one of the kinds of testimony that you will probably hear later today suggests that it is a rare occasion when long-distance transport of air pollutants occurs.

I would simply mention, on those rare occasions when long distance occurs when there has been a significant atmospheric inversion simply means a very dirty air mass standing over an area and then allowing precipitation to remove and cleanse the air and, in essence, deposit the substance in the air upon the ecosystem.

When that kind of an episodic event, although rare, coincides, say, with the time when fish larvae are developing from fish eggs, it raises havoc with the fish.

Those coincidences may not be every day occurrences, but those coincidences are the major reason why we have effects. That is why I have emphasized twice this morning that we must be concerned about coincidences between episodic events and vulnerable life stages and life forms.

Senator TSONGAS. On the point that you are making, which I think is quite valuable, let me just read the impact on New England.

For example, in New England, roughly 44 percent of the acid rain is self-generated; 39 percent is attributable to pollution from the Midwest and Midatlantic States and 17 percent is attributable to Canadian sources. Thus, the acid rain problem is also one of local concerns.

So, the problem that we have in New England, less than half of it is caused by our own, if you will, lifestyle and energy needs, and there should be some appreciation for those States to our west of what impact we are presently suffering.

Dr. COWLING. I would like to comment in that connection that all of our approaches in air pollution control have been based upon a simple idea that dilution is a solution to pollution.

And I would suggest that dillution is no solution to pollution in the form of acid precipitation. We must be concerned with the total amount of deposition, of the total amount of emissions and not alone with the ambient concentration of pollutants in the air. Senator TSONGAS. Well, I think we are getting closer to things that would fit on a bumper sticker, so we are making progress. Senator DURKIN. Would the Senator yield for an observation? You know, at Dartmouth, they have been doing studies at the Hubbard Farm for some time. And without an adequate transport model, it appears that most of the pollution is coming from the Pennsylvania-Ohio region.

And we have very little control over it. You know, we cannot pinpoint it per se, but they have done a considerable amount of work and we intend to have a hearing in New Hampshire and bring them in before the committee.

I would like to ask the doctor one question. There is much talk about solvent refined coal or SRC-1 wherein much of the sulfur has been removed prior to combustion.

From what we know today, do you think that alleviates the acid rain problem and, if so, to what degree?

Dr. COWLING. Once again, you draw me beyond my competence. I don't know——

SO

Senator DURKIN. Well, we are often doing business in that area,

[Laughter.]

Dr. COWLING. I'm not experienced in coal-cleaning chemistry, but I can certainly understand the simple principle that if you take it out before you burn it, there will be less there later.

Of course, that must be considered in economic terms, but as a biologist I cannot help but applaud a decision in terms of the forests that are my professional reason for being. If you take it out before it is combusted, that means that there will be less deposition on my forests later.

And in that sense, an effective washing technology, it seems to me, could be a very effective contribution to the alleviation of the acid precipitation problem.

Senator DURKIN. Thank you, Doctor.
Senator TSONGAS. Dr. Hendrey.

STATEMENT OF DR. GEORGE R. HENDREY, LAND AND FRESH WATER ENVIRONMENTAL SCIENCES GROUP, BROOKHAVEN NATIONAL LABORATORY, UPTON, N.Y.

Dr. HENDREY. Thank you, Mr. Chairman. I am Dr. George Hendrey. I am employed by Brookhaven National Laboratory as the head of the land and fresh water environmental sciences group. Brookhaven Laboratory is actually engaged in studying the terrestrial effects of acid deposition, as well as the aquatic effects, but we also play a significant role in data coordination, in studies of atmospheric chemistry, physics and other pollutants related to acid rain and in analysis of energy policy scenarios.

We have covered a number of the points that are presented in my written testimony. I do not want to be redundant with those things, but I would like to start by saying there is some confusion as to what is meant by the popular term "acid rain."

Acid rain actually includes rain, fog, and snow which have concentrations in excess of 2.5 microequivalents of acid per liter which is this pH of 5.6.

But acid rain, this popular term, I think many of us define it as including dry deposition of particulate matter, such as ammonium sulfate aerosols, and other aerosols which may contain toxic metals or organic substances and the dry deposition of SO2 and NO.

Acid rain is differentiated from other forms of air pollution primarily by the distance from which identifiable sources have an impact on atmospheric concentration and by having sulfuric and nitric acids as the principal contaminants

A better term than acid rain for the impacts that we are interested in is acid deposition.

Figure 2 in my text presents the data from the mid-1970's on the current concentrations of acid precipitation of acidity in precipitation. These are similar to figures prepared by likens. I am sure that almost everyone that is familiar with the area of acid precipitation has seen these before.

The important point to note is that the concentrations of acid rain today are 10 to 30 times greater than unpolluted precipitation. Furthermore, the principal contaminants, nitric acid and sulfuric acid, are changing in their relative importance.

Senator TSONGAS. Let me interrupt you, if I might. The figures that you have in your testimony show remarkable differences in acidity-well, let's take the Eastern United States and forget Europe for a moment.

How do you account for those differences? For example, if you take New England, New Hampshire seems to do quite poorly and, yet, Massachusetts seems to escape part of the worse parts of the acidity. How-why is that?

Dr. HENDREY. The concentration of these pollutants, of the pollutant acid and of the nitric acid and sulfuric acid is, of course, strongly related to the source of emission.

If I had presented a map of emission sources, both utilities and other sources of emission, you would find them to be concentrated from the area of the Great Lakes down toward the Mason Dixon line and from Indiana and Ohio over into Pennsylvania, and Illinois, as well. That area covers a general band of intense industrial activity in the United States.

Now, in the case of this particular map the pollutants emitted in that area are transported some hundreds of kilometers, and they react in the atmosphere, changing their chemical spatiation from unacidic forms to acidic forms.

That transportation and the chemical reaction and the rates of those chemical reactions, plus the rate of atmospheric transport, determine where the most heavily impacted area is going to be. That is why we see this particular type of distribution.

Senator TSONGAS. In the European model, what are the corresponding sources of pollution?

Dr. HENDREY. In Europe, the primary sources are emitted in an industrial belt of Great Britain and then in the north-central part of England, starting with the Benelux countries and running across over even into Poland.

Senator DURKIN. Doctor, on page 3, if I am reading your figure 2 correctly, following upon what Paul asked, if I am reading the exhibit correctly it would appear that New Hampshire is receiving substantially more acid deposition or whatever than the neighboring State of Massachusetts.

Do you have any supposition as to why that may be true or is it a case, maybe, of better monitoring and reporting inasmuch as there has been some work done?

Dr. HENDREY. No, sir, I don't think it is a question just of the monitoring and reporting. As we know, there is a long history of precipitation monitoring at the Hubbard Brook Research site in New Hampshire.

Much of the data that we have available to us comes from this long-term monitoring program.

Now, this was not established as a means of checking on acid rain. This was established as a study in basic sciences to try and understand ecosystems. Without that kind of study, we would not be aware of the acid rain problem.

I would also point out that, in the regions that we know to be impacted, they are primarily mountainous regions. That is where the worst effects have shown up first. This is true in Scandinavia and it is true in New Hampshire and in New York State.

A reason for that is air pollutants emitted in one region transported over relatively low terrain encounter this mountainous terrain, the air mass is forced to rise, it cools because of that rising, and you have an initial scrubbing and washout effect. That is very evident from data on the distribution of acid precipitation in the Adirondacks and the distribution of the effects of acid precipitation in the Adirondacks, and it is also evident from studies in Scandinavia.

Senator DURKIN. So, I guess the mountainous terrain of New Hampshire is probably providing a natural adverse effect.

Dr. HENDREY. That is correct. That contributes-that is a contributory factor. And it certainly is important when we get around to another aspect that we will talk about later; namely, the effect side of it.

Senator TSONGAS. Let me just say for the benefit of the witnesses that are coming afterward that we will get to you today.

We are not going to break for lunch, but will go straight through. This is an important issue and, even though we are taking longer than normal, I think it is worth spending the time.

Dr. HENDREY. I would like to point out that between 1964 and 1965, data collected in that area, through 1972-73, the acidity of precipitation measured at Hubbard Brook remained relatively constant over that period or long time span, but the ratio of contributors changed.

Sulfuric acid was altered from 83 percent to 66 percent of the total acid, while nitric acid increased from 15 to 30 percent.

Since these acids are derived primarily from oxides of sulfur and nitrogen emitted into the air by the combustion of fossil fuels for