Swift Gulch 



Chapter 3 of the final 2001 SEIS described the condition of surface and ground water 

 near the mines in detail on a drainage-by-drainage basis. Swift Gulch is a tributary of 

 the South Fork of Bighorn Creek, which crosses the reservation boundary and becomes 

 a tributary of Little Peoples Creek, which flows through the town of Hays. Swift Gulch 

 is in a canyon approximately 700 feet below and 500 feet north of the northern edge 

 of the Landusky mine pit (Figure 2). Stream distance between the Landusky mine and 

 the Fort Belknap Reservation boundary is approximately 6,000 feet. Swift Gulch flows 

 during the spring runoff, but at other times it is intermittent, surfacing and 

 submerging along its length until it is joined by the North Fork of Bighorn Creek, a 

 perennial stream. The SEIS describes concerns about the water quality of Swift Gulch 

 from ground water seeps that enter the stream between the Landusky mine pit and 

 the stream. There was some indication in 2001 that the water was acidic and had 

 elevated levels of sulfates and metals. Red orange iron precipitates coat a portion of 



the stream bottom. The water 

 quality in the headwaters of 

 ?rj Swift Gulch near the mine has 

 been deteriorating since about 

 -1999 15 j^Q water has become 

 more acidic, decreasing from 

 about pH 7.5 to pH 3.7 

 according to tribal officials, and 

 it is high in iron. The iron 

 ^>! precipitate discoloration 

 appears to be moving 

 downstream towards the 

 reservation boundary and is now 

 visible near the confluence of 

 Swift Gulch and the South Fork 

 Swift Gulch, 2004. Dean Stiffarm Photo. of Bighorn Creek. ^^ 



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The specific causes or sources of this degradation have not yet been conclusively 

 identified. The seeps in Swift Gulch are not being captured or treated at this time. 

 According to some sources, there is some evidence that the seeps may be 

 hydraulically connected to the mine operations. ^^ The quality of water coming out of 

 the seeps has become worse since the Landusky mine pit was developed. Also, the 

 mine pit intercepts a sheer zone or fault fracture area that generally runs southwest 

 to northeast beneath the northern portion of the Landusky pit complex nearest Swift 



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