32, INJURY BY SMELTER WASTES. 
INJURY TO CROPS AND SOIL BY TAILINGS AND SLAG FROM THE 
WASHOE REDUCTION PLANT. 
The third question calling for investigation was whether the water 
‘from Deer Lodge River, when used for irrigation purposes, has an 
injurious effect on the crops and the soil. It is evident from an in- 
spection of this stream that tremendous quantities of waste matter 
from the plant find their way into it. It is also evident from the 
method of operation that these waste products must contain some 
copper which is, to a large extent, present as finely divided copper 
sulphid, which is known to form soluble copper sulphate naturally 
by gradual oxidation. It would be expected, therefore, that if this 
material were deposited on the land it would gradually oxidize to a 
soluble form, in which condition even very minute quantities of it 
would be more or less injurious to vegetation. It has been urged 
that even if soluble copper were found in the Deer Lodge River and 
subsequently on the land it would be immediately rendered insolu- 
ble again by the action of carbonates and bicarbonates present in 
the water and soil. On the surface this seems plausible. Skinner, 
however, has shown that such is not the case, as when soluble copper 
salts are brought in contact with solutions containing carbonates 
and bicarbonates, enough copper still remains in solution to be toxic 
to plants. i 
Samples of the waste water from the plant, and samples from the 
Deer Lodge River just below where the waste flows into it, and at 
various distances farther down, were taken and the insoluble copper 
present was determined with the following results: 
TABLE VIII.—Copper content of irrigation water samples. 
Serial Insoluble Soluble 
Noe Location and approximate distance from smelter. copper. copper. 
Parts per | Parts per 
million. million. 
AZAGZ | SWVASGG WAGER. Os SII CL Ge res See ae we sare Stade Se 31.0 0.05 
4244____| Deer Lodge River, 13 miles below entrance of smelter water_---- UPA aie 
4240____| Deer Lodge River, 6 miles below entrance of smelter water___-_-- 12.0 EL 
4241____| Deer Lodge River, 8 miles below entrance of smelter water_____.. 6.4 22 
4242____| Deer Lodge River, 10 miles below entrance of smelter water____- 6.6 Trace. 
4243____| Deer Lodge River at Deer Lodge, about 16-18 miles below en- 
trance: of ismelter «water 2e- aeee  See ee eee eee 3.1 51 
It is evident from Table VIII that the plant discharges large 
quantities of copper into the Deer Lodge River and that, even at a 
distance of 16 to 18 miles below the point where the tailings are dis- 
charged, a considerable quantity of copper is still present. 
It has been proven by Heald ® that seedlings of the ordinary garden 
plant Piswm sativum are killed by the solution containing 1 part of 
copper in 404,423 parts of water and that Indian corn (Zea mays) 
@ Copper Salts in Irrigation Waters, J. Amer. Chem. Soc., 1906, 28-361. 
> Bot. Gaz., 1896, 22: 125. 
