Laserfiche WebLink
<br />~~2108 <br /> <br />Water-Quality by Aquifer <br /> <br />Most of the available water-quality data in table 5 in the "Supplemental <br />Information" section at the end of the report are for water samples taken from <br />the Mesaverde Formation and alluvium. Other water quality samples are grouped <br />as other bedrock in the following summary of water quality of aquifers. <br /> <br />Table 5 includes analyses for samples from 19 wells completed in the <br />Mesaverde Formation. The range of specific conductances was from 325 to <br />5,390 ~S/cm with an average of 1,434 ~S/cm. The range of dissolved solids was <br />from 206 to 3,360 mg/L with an average of 880 mg/L. The dominant cation was <br />sodium and the dominant anions were bicarbonate and sulfate. Concentrations <br />of dissolved solids, sulfate, iron, and manganese in some samples exceeded the <br />U.S. Environmental Protection Agency's (U.S. EPA) standards for secondary <br />maximum contaminant levels of public drinking waters. Concentrations of <br />fluoride and selenium exceeded the U.S. EPA primary drinking water standards <br />in some samples. <br /> <br />Samples were taken from 10 wells completed in other bedrock and the range <br />of specific conductances was from 173 to 1,900 ~S/cm and averaged 886 ~S/cm. <br />The range of dissolved solids was from 123 to 1,262 mg/L and averaged <br />618 mg/L. The dominant cation was sodium and the dominant anion was <br />bicarbonate. Concentrations of sulfate, dissolved solids, iron, and manganese <br />exceeded ~he secDndar~ maximum cDn~aminan~ levels established by the U.S. EPA. <br /> <br />Samples were taken from 10 springs that issued from other bedrock. <br />Specific conductances ranged from 275 to 18,500 ~S/cm and averaged <br />3,564 ~S/cm. The range of dissolved solids was 166 to 12,400 mg/L and <br />averaged 2,577 mg/L. The dominant cation was calcium and the dominant anion <br />was bicarbonate. Concentrations of sulfate, dissolved solids, chloride, and <br />manganese exceeded the U.S. EPA secondary standards in some samples. Fluoride <br />concentrations exceeded the U.S. EPA primary standards in some samples. <br /> <br />The water quality of samples taken from alluvium and unconsolidated <br />deposits were more suitable for domestic use than bedrock water, although <br />water samples from alluvial wells were more similar to bedrock water quality <br />than springs that issued from alluvium. Water quality samples from 6 wells <br />completed in alluvium and unconsolidated deposits ranged in specific <br />conductance from 80 to 32,200 ~S/cm. The range of dissolved solids was 63 to <br />2,970 mg/L. The dominant cation was calcium and the dominant anion was <br />bicarbonate. Concentrations of sulfate, dissolved solids, manganese, and <br />chloride exceeded the U.S. EPA secondary standards in some samples. The <br />selenium concentration in one sample exceeded the U.S. EPA primary drinking <br />water standard. <br /> <br />Water quality of samples taken from 8 springs that issued from alluvium <br />and unconsolidated deposits were the best in the study area. The range of <br />specific conductance was from 48 to 510 ~S/cm and the range of dissolved <br />solids was from 46 to 305 mg/L. The dominant cation was calcium and the <br />dominant anion was bicarbonate. No chemical constituents exceeded the primary <br />or secondard standards established by the U.S. EPA. <br /> <br />11 <br />