Trail Smelter Arbitration (United State/Canada), 3 U.N Rep. Int’l Arb. Awards 1905 (1941)
This Tribunal is constituted under, and its powers are derived from and limited by, the Convention between the United States of America and the Dominion of Canada signed at Ottawa, April 15, 1935, duly ratified by the two parties, and ratifications exchanged at Ottawa, August 3, 1935 (hereinafter termed “the Convention”).
The duty imposed upon the Tribunal by the Convention was to “finally decide” the following questions:
1) whether damage caused by the Trail Smelter in the State of Washington has occurred since the first day of January, 1932, and, if so, what indemnity should be paid therefor?
2) In the event of the answer to the first part of the preceding question being in the affirmative, whether the Trail Smelter should be required to refrain from causing damage in the State of Washington in the future and, if so, to what extent?
3) In the light of the answer to the preceding question, what measures or regime, if any, should be adopted or maintained by the Trail Smelter?
4) What indemnity or compensation, if any, should be paid on account of any decision or decisions rendered by the Tribunal pursuant to the next two preceding questions?
In 1896 a smelter was started under American auspices near the locality known as Trail. In 1906, the Consolidated Mining and Smelting Company of Canada, Limited, obtained a charter of incorporation from the Canadian authorities, and that company acquired the smelter plant at Trail as it then existed. Since that time, the Canadian Company, without interruption, has operated the Smelter, and from time to time has greatly added to the plant until it has become one of the best and largest equipped smelting plants on this continent. In 1925 and 1927, two stacks of the plant were erected to 409 feet in height and the Smelter greatly increased its daily smelting of zinc and lead ores. This increased product resulted in more Sulphur dioxide fumes and higher concentrations being emitted into the air; and it is claimed by one Government (though denied by the other) that the added height of the stacks increased the area of damage in the United States. In 1916, about 5,000 tons of sulphur per month were emitted; in 1924, about 4,700 tons; in 1926, about 9,000 tons—an amount which rose near to 10,000 tons per month in 1903. In other words, about 300-350 tons of Sulphur was being emitted daily in 1930. (It is to be noted that one ton of Sulphur is substantially the equivalent of two tons of sulphur dioxide or SOZ.)
From 1925, at least, to the end of 1931, damage occurred in the State of Washington, resulting from the sulphur dioxide emitted from the Trail Smelter.
The first question under Article III of the Convention which the Tribunal is required to decide is as follows: (1) Whether damage caused by the Trail Smelter in the State of Washington has occurred since the first day of January, 1932, and, if so, what indemnity should be paid therefor.
The Tribunal has first considered the items of indemnity claimed by the United States in its Statement (p. 52) “on account of damage occurring since January 1, 1932, covering: (a) Damages in respect of cleared land and improvements thereon; (b) Damages in respect of uncleared land and improvements thereon; (c) Damages in respect of livestock; (d) Damages in respect of property in the town of Northport; (g) Damages in respect of business enterprises”.
On the basis of the evidence, the United States contended that damage had been caused by the emission of sulphur dioxide fumes at the Trail Smelter in British Columbia, which fumes, proceeding down the valley of the Columbia River and otherwise, entered the United States. The Dominion of Canada contended that even if such fumes had entered the United States, they had caused no damage after January 1, 1932. The witnesses for both Governments appeared to be definitely of the opinion that the gas was carried from the Smelter by means of surface winds, and they based their views on this theory of the mechanism of gas distribution. The Tribunal finds itself unable to accept this theory. It has, therefore, looked for a more probable theory, and has adopted the following as permitting a more adequate correlation and interpretation of the facts which have been placed before it.
A careful study of the time, duration, and intensity of the fumigations recorded at the various stations down the valley reveals a number of striking and significant facts. The first of these is the coincidence in point of time of the fumigations. The most frequent fumigations in the late spring, summer, and early autumn are diurnal, and occur during the early morning hours. These usually are of short duration. A characteristic curve expressing graphically this type of fumigation, rises rapidly to a maximum and then falls less rapidly but fairly sharply to a concentration below the sensitivity of the recorder. The dominant influence here is evidently the heating action of the rising sun on the atmosphere at the surface of the earth. This gives rise to temperature differences which may and often does lead to a mixing of the gas-carrying atmosphere with that near the surface. When this occurs with sufficient intensity, fumigation is recorded at all stations at which the sulphur dioxide reaches, a concentration that is not too low to be determined by the recorder. Obviously this effect of the rising sun may be different on the east and the west side of the valley, but the possible bearing of this upon fumigations in the valley must await further study.
Another type of fumigation occurs with especial frequency during the winter months. These fumigations are not so definitely diurnal in character and are usually of longer duration. The Tribunal is of the opinion that these are due to the existence for a considerable period of a sufficient velocity of the gas-carrying air current to cause a mixing of this with the surface atmosphere. Whether or not this mixing is of sufficient extent to produce fumigation will depend upon the rate at which the surface air is diluted by surface winds which serve to bring in air from outside the contaminated area. The fact that fumigations of this type are more common during the night, when the surface winds often subside completely, bears out this opinion. A fumigation with a lower velocity of the gas-carrying air current would then be possible. The conclusions above together with a detailed study of the intensity of the fumigations at the various stations from Columbia Gardens down the valley, have led to deductions in regard to the rate of attenuation of concentration of sulphur dioxide with increasing distance from the Smelter which seem to be in accord both with the known facts and the present theory.
The conclusion of the Tribunal on this phase of the question is that the concentration of sulphur dioxide falls off very rapidly from Trail to a point about 16 miles downstream from the Smelter, or 6 miles from the boundary line, measured by the general course of the river; and that at distances beyond this point, the concentration of sulphur dioxide is lower and falls off more gradually and less rapidly.
The Tribunal will now proceed to consider the different classes of damage cleared and to uncleared land.
(1) With regard to cleared land used for crops, the Tribunal has found that damage through reduction in crop yield due to fumigation has occurred in varying degrees during each of the years, 1932 to 1936; and it has found no proof of damage in the year 1937.
(2) With respect to damage to cleared land not used for crops and to all uncleared (other than uncleared land used for timber), the Tribunal has adopted as the measure of indemnity, the measure of damages applied by American courts, viz-, the amount of reduction in the value of the use or rental value of the land. The Tribunal is of opinion that the basis of estimate of damages contended for by the United States, viz-, applying to the value of uncleared land a ratio of loss measured by the reduced crop yield on cleared land, has no sanction in any decisions of American courts.
(3) With regard to “damages in respect of livestock”, claimed by the United States, the Tribunal is of opinion that the United States has failed to prove that the presence of fumes from the Trail Smelter has injured either the livestock or the milk or wool productivity of livestock since January 1, 1932, through impaired quality of crop or grazing. So far as the injury to livestock is due to reduced yield of crop or grazing, the injury to livestock is due to reduced yield of crop or grazing, the injury is compensated for in the indemnity which is awarded herein for such reduction of yield.
(4) With regard to “damages in respect of property in the town of Northport”, the same principles of law apply to assessment of indemnity to owners of urban land as apply to owners of farm and other cleared land, namely, that the measure of damage is the reduction in the value of the use or rental value of the property, due to fumigations. The Tribunal is of opinion that there is no proof of damage to such urban property; that even if there were such damage, there is no proof of facts sufficient to enable the Tribunal to estimate the reduction in the value of the use or rental value of such property; and that it cannot adopt the method contended for by the United States of calculating damages to urban property.
(5) With regard to “damages in respect of business enterprises”, the counsel for the United States in his Answer and Argument (p. 412) stated: “The business men unquestionably have suffered loss of business and impairment of the value of good will because of the reduced economic status of the residents of the damaged area.” The Tribunal is of opinion that damage of this nature “due to reduced economic status” of residents in the area is too indirect, remote, and uncertain to be appraised and not such for which an indemnity can be awarded…
(6) The United States in its Statement (pp. 49-50) alleges the discharge by the Trail Smelter, not only of “smoke, sulphurous fumes, gases”, but also of “waste materials”, and says that “the Trail Smelter disposes of slag in such a manner that it reaches the Columbia River and enters the United States in that stream”, with the result that the “waters of the Columbia River in Stevens County are injuriously affected”, thereby. No evidence was produced on which the Tribunal could base any findings as regards damage, if any, of this nature…
In conclusion, the Tribunal answers Question 1 in Article III, as follows: Damage caused by the Trail Smelter in the State of Washington has occurred since the first day of January, 1932, and up to October 1, 1937, and the indemnity to be paid therefor is seventy-eight thousand dollars ($78,000), and is to be complete and final indemnity and compensation for all damage which occurred between such dates. Interest at the rate of six per centum per year will be allowed on the above sum of seventy-eight thousand dollars ($78,000) from the date of the filing of this report and decision until date of payment. This decision is not subject to alteration or modification by the Tribunal hereafter.