Laserfiche WebLink
Ground Water Quality. Ground water samples were collected from two wells <br />on a biannual basis. The parameter list used for all wells sampled this <br />year is given on Table 4. Analyses have been performed by ACZ Laboratory <br />in Steamboat Springs, Colorado since May 31, 1983. ACZ Laboratory <br />performs all analyses by EPA or equivalent methods. Samples are <br />delivered the day of collection to the lab in an iced cooler. The old <br />ground water monitoring program is presented on pages 7-341/342 of the <br />Seneca II PAP. The new program is provided in the PR-02 package (Volume <br />14) on page 2.04.7-2. <br />The following discussion of the analytical data collected during the <br />reporting period is arranged by strata being monitored and coincides <br />with the format (by aquifer type) in which the analytical data are <br />presented in Appendix C. The discussion of water quality will be limited <br />to a description of total dissolved solids (TDS) concentrations. A <br />separate section, Comparison of Ground Water Quality to Water Use <br />Standards, will discuss any samples that exceed water use standards. <br />Data for each well in this appendix begins with a listing of the water <br />quality data collected during the past two years, followed by remarks <br />explaining the sampling procedure. This is followed by a plot of TDS <br />versus time for the entire period of record. The regression line on this <br />plot is generated by a method known as LOWESS (LOcally WEighted <br />Scatterplot Smoothing). Unless otherwise noted, a smoothness factor (SF) <br />of 1.0 (on a scale of 0 to 1) was used, which results in maximum <br />"smoothing". Finally, this plot is followed by a table listing historic <br />TDS values and percent milliequivalents for major ions. <br />- Alluvium. Well 68, completed in the Bond Creek alluvium (below NPDES <br />Pond 008), was drilled in 1988. Recently, it displays a stable TDS <br />trend. <br />Well 72 is located in the Fish Creek alluvium below all Seneca II and <br />PSCM discharges. This well was drilled and completed by Twentymile Coal <br />Company as part of their monitoring program. The first sample collected <br />by Seneca at this GWPOC well was last year. <br />4