INJURY TO VEGETATION BY SMELTER FUMES. 



INTRODUCTION. 



The investigation described in this bulletin was undertaken at the 

 request of the United States Department of Justice in consequence 

 of a suit brought by the United States against the Mountain Copper 

 Company (Limited), a corporation operating a large copper-smelting 

 plant situated near Redding, Shasta County, Cal. The investigation 

 was made to show whether or not the fumes from this plant are inju- 

 rious to vegetation, and, if such injury exists, over how large an area 

 it extends. While the company is willing to acknowledge damage 

 over, a certain limited area surrounding the plant, it was thought by 

 the plaintiff in the case that this damage extenti! % 3 over a much lars^r 

 area than was acknowledged by the defendant. 



The writer was detailed to inspect the disputed area and take such 

 samples for chemical analysis as might appear to be necessary. It 

 was constantly borne in mind during this investigation that for a cer- 

 tain distance injury to vegetation was acknowledged, so that the tak- 

 ing of samples in this area was unnecessary. Consequently all sam- 

 ples of vegetation were taken either on the extreme edge or outside 

 of the area of acknowledged damage, which, when plotted on the map, 

 shows itself in the form of an irregular ellipse surrounding the smelter 

 and extending about 3 miles north, 2J miles south, 1 mile east, and 

 3 miles west. About 60 samples of the trees, water, soil, and ore 

 were taken and subjected to chemical analysis, from which very 

 definite results have been obtained. It might be well to describe first 

 the situation of the smelter and the general appearance of the vege- 

 tation in the region as it presented itself to the chemist. 



LOCATION OF SMELTER AND APPEARANCE OF SURROUNDING 



VEGETATION. 



The smelter is situated in a narrow valley, or what might almost be 

 termed a cut between the mountains. Its highest chimneys are far 

 below the level of the surrounding land. In a northerly and westerly 

 direction other narrow gulches branch off from this main one, so that 

 the fumes have a tendency to keep together and drift for long dis- 

 tances in these natural chimneys. In a southerly direction the fumes, 



