0141bU4 



adjacent mountains receive up to 76.2 cm (30 in) of annual 

 precipitation (Soil Conservation Service 1977). The climate is 

 modified continental with an average annual temperature of 6.3°C 

 (43.3°F) (National Oceanic and Atmospheric Administration (NOAA) 

 1983). Average January and July temperatures at Helena are -8°C 

 (18.1°F) and 20°C (67.9°F) respectively (NOAA 1983). Agricultural 

 crops in the Valley are alfalfa, small grains (usually wheat, 

 barley and some oats) and range land. 



The Helena Valley is the site for two incorporated cities: 

 Helena and East Helena with approximate populations of 23,900 and 

 2,400 respectively (1980 census). The two cities are located 6.4 

 (4 mi) and 1 km (0.6 mi) from the smelter complex, respectively. 



The valley has been the site of a lead smelter since the 

 Helena and Livingston facility was built in East Helena in 1888. 

 The smelter was purchased by its present owner (American Smelting 

 and Refining Company) in 1899. The Anaconda Company built a zinc 

 plant adjacent to the smelter in 1927 to recover zinc from waste 

 products. In 1955 the American Chemet Company constructed a paint 

 pigment plant utilizing zinc oxide from the zinc facility. 



