progressively concentrated through the food chain and is most toxic in its 

 methylated form. Certain micro-organisms have the ability to methylate 

 mercury in the natural environment, therefore, it is recommended that total 

 mercury levels rather than one particular form be the basis for a mercury 

 criterion. It has been observed that over a period of 20-48 weeks, several 

 species of fish had the ability to accummulate more than .5 ug/g of mercury 

 in tissues from aquatic concentrations of methyl mercury as low as 

 .018 to .030 ug/1 (USEPA, 1976). Mercury concentrations in California Creek 

 may represent a potential threat to fish populations if methylatinq conditions 

 are present. It is not known whether the mercury is present from natural or 

 man-caused sources such as mining activity. 



Concentrations of copper and zinc in Oregon, California and French Creeks 

 were found to be at very low or trace levels. In general, dissolved heavy 

 metal concentrations in the three streams do not appear to pose an immediate 

 threat to fish populations. No sediment chemistry analyses were performed on 

 the Mount Haggin streams. It has been found that sediments in a heavily mined 

 area of Grasshopper Creek, Montana contained very high levels of heavy metals 

 while water samples showed low levels of the dissolved forms of the same 

 constituents (Peterson, 1979). This reach of Grasshopper Creek was observed 

 to support depressed populations of trout and aquatic invertebrates. It is 

 possible that the sediments of Oregon, California and French Creeks contain 

 elevated levels of heavy metals and may represent a further threat to fish 

 populations. Another ramification of heavy metals concentrations exists 

 because of the soft water of the Mount Haggin streams. Some metals, especially 

 copper and lead, become more soluable and more toxic in soft water. For this 

 reason, heavy metals must be regarded as a potential threat to fisheries in 

 some Mount Haggin streams. 



d) Sediments 



Most of the Mount Haggin streams were found to carry very small loads 

 of suspended sediment despite the occurrance of intensive logging activity 

 in the surrounding areas. This may be due to the presence of numerous beaver 

 ponds which act as sediment traps. High levels of a milky gray sediment were 

 measured in California and French Creeks on the day after a rain shower during 

 the intermediate flow period. Much lower amounts of the sediment were observed 

 in Willow Creek two days after the rain. The sediment originates on the slopes 

 near Sugarloaf Mountain which hold tributaries of California and Willow Creeks. 

 California Creek is the main tributary of French Creek. These slopes are 

 poorly vegetated and exhibit large areas of eroded gray soils. The area has 

 had a past history of heavy logging, grazing, fires and damage to vegetation 

 from arsenic and sulphide precipitates from the Anaconda Smelter. These 

 factors have combined to produce the poorly vegetated erodable slopes in the 

 area. 



Numerous studies have shown that sediments can be extremely detrimental 

 to the aquatic ecosystem. Some major effects of sedimentation are loss of 

 spawning gravels or actual smothering of fish eggs and loss of benthic food 

 organism via the filling of gravel interstices. Sediment levels as low as 

 80 mg/1 have been found to decrease standing crops of macroinvertebrates by 

 60 percent both in areas where the sediment was suspended and where it had 



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