Laserfiche WebLink
Both Hubberson Gulch and Dry Creek may potentially be impacted by mining, <br />specifically by spoils discharge recharging the streams. Dependent upon the time <br />of year, Dry Creek may be recharging its alluvium, or the alluvium may be adding <br />water to the creek. Furthermore, dependent upon local conditions, dischazges from <br />the predicted spoils aquifer may infiltrate the Hubberson Gulch alluvium. This <br />water may flow through the alluvium downgradient to recharge the Dry Creek <br />alluvium from which Olson Spring issues. <br />It is projected by the applicant that, due to dilution, there will be no impact to Olson <br />Spring quality which may be attributed to mining. An alluvia] cross-section of wells <br />in Hubberson Gulch upgradient of the spring will help monitor the advance of any <br />plume in that gulch. A water quality monitoring plan was initiated at Olson Spring <br />to provide baseline data of this spring. <br />Seneca Coal Company has included a plan for an alternative water supply in the <br />event that local water rights aze adversely impacted by mining. The plan is included <br />in Tab 16 of the permit. <br />Ten springs which are present in or adjacent to the permit area were chosen for <br />further study. At each of these sites, three water quality and discharge <br />measurements were made during the sutnmer and fall of 1983. Typically, quality <br />and quantity varied from spring to spring. <br />In general, the water was very hard with average TDS values ranging from 458 mg/1 <br />to 2,150 mg/I. Sulfate was generally more dominant than bicarbonate. All but two <br />springs experienced a decline in flow during the course of the summer. Five had <br />dried up by late August, three others flowed less water during base flow and two <br />were flowing at about the same rate in October as in June. <br />Three springs, Olson Spring, S-5, and S-41, are expected to be impacted by mining, <br />one of which, 5-41, feeds a registered stock pond. Olson Spring is an adjudicated <br />domestic water right. A discussion of this can be found in Section III F. - <br />Assessment of Probable Hydrologic Consequences of Mining. <br />SCC perfotTrls a spoil spring survey following snowmelt each year, with locations <br />of springs of greater than 10 GPM of discharge reported to the Division by the end <br />of May. An annual total of approximately 2 full-suite samples and 4 field <br />parameters samples are collected each year, timed in order to chazacterize water <br />quality and flow during the high-water and low-water seasons. <br />Seneca lI-W Findings Documen[ 24 November 3, 1999 <br />