for hiking and camping. They have used these resources for many years and they have a right to continue to do so.

And what of the St. Croix Valley Rod & Gun Club who drive their major income from a large ice fishing contest every year? A sizable portion of these funds are used to develop and foster good hunting and fishing habits in our youth. Both of these groups, too, lay claim to a portion of the river.

What of the Hudson Boosters who sponsor auto racing on the river's ice each winter? Their income from the annual event is used to support little league baseball during the summer. Their right to continue this program should be protected.

Many more groups could be listed, each day more and more citizen organizations, conservation groups, and various communities lay claim to their share of this resource. For too long we have been unaware that it needed active protection, but now we face an impending desire by the few to take what is not rightfully theirs alone.

I speak not entirely of the power company, but also of those proponents of extensive valley industrialization at the expense of dissipating a public resource for their own profit without due recourse to proper democratic or corporate practice.

In a corporation, as we know, all of the owners or their representatives must agree to sell before ownership can transfer. We submit that the resources of this valley are also public property, so all who share in these resources should also have a voice in its impending sale. We are obligated to preserve the recreational aspects of this river, not only for the present but also for future generations. In addition to its recreational values, we must also consider the industrial potential of the St. Croix Valley. Sound long-range planning dictates that we do not abandon our clean, cool water to one industry who would spoil it and jeopardize our present favorable position to future industry that could locate here without destroying the recreational values of our river.

The problems we face in this valley have been explained in a general way, so I will turn to the specifics of heat pollution."

First, I would stress that fact that the amount of heat pollution is dependent upon the flow for heat dilution. As General Wilson, Chief of Engineers, U.S. Army Corps of Engineers, has said, "Dilution is not the solution to pollution.'

This is our opinion, gentlemen, on diluting the flow, diluting the heat exchange.

The riverflow data we have used for our calculations has been collected from flow records published by the U.S. Geological Survey. We have added the recorded flow of the St. Croix at Taylors Falls, Minn., to the Apple River at Somerset, Wis., to arrive at an estimated flow at the proposed powerplant site, so we feel this method is quite

accurate.

Lowest flow at the plant site was 80 cubic feet per second in 1910. The average flow of the river is calculated over a long period 4,328 cubic feet per second. According to the Northern States factsheet. and their permit request to the Minnesota Water Pollution Control Commission, the plant will need 660 cubic feet per second, or 300,000 gallons per minute. This represents 825 percent, or more than eight

times the low flow. I would also stress the fact that this is 15.3 percent of the total average flow, which includes all of the flood flows in many years which has occurred and brings the average very high.

Before going on, I would like to emphasize the fact that the technology of thermal transfer or heat exchange in rivers is not an exact science. It is an approximate science.

Senator NELSON. Mr. Mertes, are there any estimates on the cubic footage of water in St. Croix Lake?

Mr. MERTES. Mr. Chairman, we have hoped to calculate this, but we have not as yet accomplished this. We hope that some of the studies that are being accomplished will come up with this answer and compare the total volume in the lake with the volume needed to cool the turbines.

Senator NELSON. I think that would be a significant factor because if a second unit of this plant were built and some 1,200 or 1,400 cubic feet per second were being used and the riverflow was low there might be very dramatic consequences, it seems to me, in heating up the whole lake all the way down to the dam. I think it would be of value to this committee, and to the Minnesota Pollution and Conservation Committee, to have statistics submitted as to what would be the effect on this lake at such time as the powerplant was using the total flow of the rivers; and how long it would take when it was using the total flow to fill the whole lake with water that had been heated in the plant from 10° to 17°. I realize some of these things would take some long scientific investigation, but if we knew the total cubic feet in that lake we would have some rough estimate how long it would take before the heated water constituted total footage in the lake.

Mr. MERTES. We could calculate this, Mr. Chairman, if you would prefer, and I am not sure we could have it completed by the time the record is closed on this hearing, but we would be glad to do this if the task force is not already going to accomplish this.

Senator NELSON. I don't know whether the task force will or not. Mr. MERTES. We could contact the task force. If they have intentions to do this we will not duplicate it; if they do not we will calculate it and furnish it.

Senator NELSON. All right.

Mr. MERTES. I was stating that the technology of thermal transfer is not an exact science, but it is an approximate science. We have been able to delineate there is a problem, but how great it is is another item. The point is that we have a potential problem to bring out, you are innocent until proven guilty, but when health hazards are concerned, we have proposed to reverse the rule to read, "Guilty until proven innocent."

Our history is a long story of about learning about potentials too late after people become sick and resources have been lost as detergents, atomic fallouts and many, many other items, X-rays, these are all on history in finding out there is damage later. I think we should figure these are potential dangers and find out whether or not they can be solved before we pose them.

Now let's consider some of the facts concerning the amount of riverflow this proposed plant will ultimately use:

The data presented by NSP states an anticipated rise of 10° to 17° of the water passing through the plant for cooling. If the riverflow equals the plant needs, the whole river will be heated approximately 15°. If the riverflows are less than plant needs, recirculation will raise the temperature in excess of 15°. If, for example, the water temperature was 70° F., as it is many times during our summers, and the plant needs dictated recirculation four times this could mean that the water temperature could reach 100° F., as it is many times this could mean that the water temperature could reach 100° F. in the discharge area, that is, if the proper distribution did not take place or the transfer within the pool did not result rapidly.

Would you put the one chart up, Mike?

As an example of flows, I have tabulated, in the form of a bar graph, the lowest average daily flow that has occurred for the period 1910-50 which, you can see on the chart, is the index on the left-meaning the minimum average daily flow-that has occurred during this period. The bottom indicates the years. I have also shown in red which is the desired flow that the plant proposes to use. The upper line-the green-is the line which would be the estimated flow that the ultimate plant would need and, as indicated, the flows definitely are not sufficient to supply more than plant needs but almost equals it on the initial plant and on the ultimate plant only 37 of the 40 years would the low riverflow have been equal to the plant needs. This chart we will furnish for the record by the 18th in another form.

The other chart which I have prepared is a typical low-flow year which indicates the trends throughout the whole year. The index on the left also is the flow that occurs during each day during the year, and it is during the year 1936 and 1937, and in the lower dashed

line is the line which the initial plant is proposed to use. The solid red line is the ultimate plant usage which indicates that many, many times, except during the high-flow years, the plant needs will equal or exceed the riverflow. I will submit this also for the record.

At this time I would like to point out the proposed plant orientation with respect to the surrounding topography. The Stillwater sewage plant, like most sewage plants, does not give complete treatment and it is located just upstream from the plant on the same side of Lake St. Croix. The proposed location of the powerplant is approximately 1,000 feet above the north end of what is called Andersen's Bay, which also will be used as a discharge channel to the river. Along the bay is the village of Bayport, which also has its beach at the mouth of the bay.

I have prepared another chart which shows these various aspects and items which I would like to point out quickly and which also will be submitted for the record. (See chart on p. 116.)

We have shown on here, which is true to scale-made up from the aerial photograph we have on the wall back there the sewage treatment plant; the marina above it; and the possible flows that may come out of the sewage treatment plant. I have also indicated a temperature of 72° in the upper portion above the plant intake which was a temperature recorded in two of the Minnesota Health Department water-sampling programs.

If the water is pulled in which is mixed with some of the sewage, heated 17° in the plant, we would have a resultant temperature of 99° in Andersen's Bay. According to the power company statement by Mr. Hill at the water pollution commission board meeting, the flow would be retained somewhere in the neighborhood of 10 hours in the bay losing 3°, so we would have a resulting temperature from this situation of 96° as it passes by the public beach and enters the mixing zone of the river.

I might point out that the coal pile, as indicated, is drawn to scale. I would like to indicate the size of it. It is large enough to put the whole Andersen Corp. plant in it which would be a shame, because, that is a very, very clean and beautiful industry.

Water, which has a large amount of oxygen within it, dissolved or free, has a maximum capability to carry or hold oxygen based on the temperature of the water. If water is heated, some oxygen will be driven off. The carrying capacity reduces quite sharply. This then means that, as the plant heats the water, oxygen will be driven off. The amount will vary with the amount of heating.

Oxygen recovery in a stream occurs by various means:

(1) Rapids in a river, which we do not have on the St. Croix below this site;