711.4215 Air Pollution/438
The Acting Secretary of State to the Chargé in Canada (Boal)
Sir: Adverting to conversations which recently took place at Ottawa in regard to the Trail Smelter case, I write to inform you that the United States Experts who are studying the effects in the State of Washington of the operation of the smelter at Trail report that beginning at 9 a.m. on March 9, 1933, and persisting until 12:40 a.m. on March 12, a period of 51.67 hours, the conductivity recorder at Northport, Washington, registered contamination of the atmosphere with sulphur dioxide. The maximum sulphur dioxide concentration recorded during the course of the 51.67 hour fumigation was 82 p.p.m. which occurred about 5 p.m. March 11.
It is reported also that beginning at 8:40 a.m. on April 5, 1933, and persisting until 12 noon of the same day, a period of 3.33 hours, the conductivity recorder at Northport registered contamination of the atmosphere with sulphur dioxide. The maximum concentration recorded during the course of this 3.33 hour fumigation was 1.09 p.p.m. which occurred at about 9:20 a.m.
You will please communicate this information to the Department of External Affairs and say that the Government of the United States expects the Canadian Government to take such steps as may be necessary to prevent a recurrence of fumigations of the duration and intensity such as were recorded from March 9 to 12 and on April 5, 1933. It should be added that in segregating these two instances of fumigation, it is not intended to convey the impression that the Government of the United States does not object to other fumigations which occur from time to time. These two instances were of such significance that the Experts deemed it desirable to report on them in advance of making a complete analysis.
You may add that in the light of all that has transpired in relation to the smelter matter the Government of the United States feels warranted in insisting that the entire controversy be promptly adjusted.
Very truly yours,