Laserfiche WebLink
Dissolved Metals <br />The following dissolved metals were not detected in any samples collected: Aluminum, <br />beryllium, chromium, cobalt, nickel, silver, vanadium, zinc, antimony, cadmium, copper, <br />lead, thallium, and mercury. All dissolved metals detections are shown in bold text in <br />Table 1. <br />Dissolved metals results are compared to the Colorado Basic Standards for Groundwater <br />in Tables 1, 2, and 3. (http //www cdphe state co us/re_gulationslwgccre?s/index.html). <br />The values for the basic standards for dissolved metals are provided in Table 1. If there <br />is no health-based standard for a metal, the secondary or agricultural standard is listed. <br />Any exceedances to the basic standards are shown as shaded cells. The only dissolved <br />metal detection to exceed a drinking water standard is that for selenium in alluvial well <br />sample MW004. This selenium detection appears to be anomalous relative to the other <br />results. Results from the next sampling event will help to determine if the selenium <br />exceedance is reproducible. <br />Secondary standards for manganese are slightly exceed in the production wells, and are <br />more elevated in alluvial wells MWO02 and MW004. Secondary standards for dissolved <br />iron are exceeded in the production wells. Secondary standards are typically associated <br />with aesthetic impacts to water quality, including taste, staining potential, and potential <br />for fouling. <br />General Chemistry <br />Results of the general chemistry results are presented in Table 1. Asbestos results are <br />included with the general chemistry. No asbestos was detected in any of the water <br />samples. Anion and cation balances are generally very good, with a maximum percent <br />difference of six percent in any of the samples. The ion balances indicate that all major <br />anions and cations are accounted for in the sampling program. <br />General chemistry parameters do not have primary health based standards. Fluoride, <br />chloride, and sulfate have secondary or agricultural standards. The sulfate <br />concentrations in all of the wells sampled exceed the secondary domestic drinking water <br />standard of 250 mg/L. Excess sulfate in drinking water may have negative aesthetic <br />impacts such as laxative effects. <br />Well MWO04 stands out with the highest sulfate, TDS, and nitrate concentrations. <br />MWO04 is located in the most extensive flood plain setting of the three alluvial wells, and <br />may be subject to more saturated geochemical conditions, relative to the other two <br />alluvial wells. <br />4