Phosphorous concentrations in Hailstone Reservoir were in the mid- 

 range for hydrologically similar sites, as were ammonium and total 

 organic carbon concentrations. 



Arsenic, boron, chromium and nickel concentrations were at or near 

 the high end of ranges for hydrologically similar sample sites. 

 Chromium and nickel concentrations in Hailstone Reservoir were 

 higher than for any other sample site. 



Chemical history. No previous chemical analyses are known for 

 Hailstone Reservoir. Anecdotal observations indicate that the 

 reservoir has been experiencing progressive salinization for a 

 number of years, probably since the construction of the dam. The 

 concentration and volume at which the reservoir solute load would 

 be in approximate equilibrium with ground-water outflow is not 

 known . 



In October of 1994, specific conductance at the WET24 site was 

 59600 microsiemens/cm, a 35% increase over the conductance measured 

 at the time of sampling in April 1993. At the same time, ground 

 water discharging into Cedar Creek at the seepage face of the dam 

 showed specific conductance of only 39700 microsiemens/cm. This 

 salinity contrast may reflect dilution by comparatively dilute 

 ground water (a nearby spring produces water with specific 

 conductance of 1560 microsiemens/cm). Alternatively, the lower 

 salinity may reflect reservoir seepage at times of more dilute lake 

 chemistry. 



Spatial variability in salinity within Hailstone Reservoir has not 

 been measured but is probably not great under most circumstances 

 due simple lake geometry and wind exposure. 



Sediments. Trace element concentrations measured in Hailstone 

 Reservoir sediments were for the most part below detection limits; 

 those with detectable concentrations occur at low to moderate 

 concentrations compared to hydrologically and regionally similar 

 sites. Several trace elements prominent in the Half breed Lake 

 sediment analysis and in the Hailstone Reservoir water column are 

 below detection limits in Hailstone sediments. This contrast may 

 reflect the physical character of sediments found at WET24; trace 

 elements in solution may have aa relatively low affinity for the 

 reworked sand observed in the vicinity of the sampling site. 



