2014-08-13_PERMIT FILE - C1981018A (2)

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• II.C.2.c Surface Water Quality Seven sites on and adjacent to the lease area were chosen for the collection of baseline surface water quality data (see Figure II.C-11). Stations were established to obtain data from streams and stock-watering ponds located above, on, and below the lease area. In addition, selected samples were collected at other sites in the area on a noncontinuing basis to better inventory the hydrologic conditions. Published information was also searched for local data. Water quality information was found for the White River above Rangely, Colorado as published by the U.S. Geological Survey in their annual Water Resources Data books. Stations SW1-1, SW11-1, and SW31-1 were each equipped with three single-stage samplers (Guy and Norman, 1970; see Figure II.C-12) set at different elevations in the stream channel for the collection of water quality data and acrest-stage gauge (Buchanan and Somers, 1969; see Figure II.C-13) for estimating peak flows. Stations SW23-1 and SW24-1 were equipped with two single-stage samplers and a crest gauge. The crest gauge inlets were raised off the bottom of the stream channels to avoid potential sedimentation problems. The single-stage samplers, which were originally developed to obtain sediment samples near the water surface during the rising part of a hydrograph, were installed to allow the collection of ephemeral runoff water quality data should access to the site be impossible during a runoff event or should the event occur when the area was unattended. Samples collected in the stage samplers at a given stream station were composited if the flow depth was great enough to fill more than one sampler. Channel cross sections were also surveyed and astage-discharge curve developed for each of the stations based • on Manning's open channel flow equation to allow an estimate to be made of the flow at the time a stage sample was collected. Figures II.C-14 through II.C-16A and II.C-17 through II.C-19B present the profiles, elevations, and stage-discharge curves of the nine sites. The remaining four surtace water quality stations noted in Map 137 were established for the collection of grab samples. Samples were collected from the designated stock ponds near the deep ehd affer wading into the pond. Stations on the White River above and below the tributaries draining the lease area were established just below a bend in the river to take advantage of the natural mixing action created when the water impinges against the river bank. Grab samples collected from the river were near surface samples collected at only one stream vertical. Because a depth-integrating sampler was not used and intake velocities were presumably not representative of stream velocities, the water quality data collected on the White River should be interpreted with caution. However, the approximations obtained by these nonstandard methods were regarded as adequate for this inventory since more representative data are collected immediately downstream by the U.S. Geological Survey. Water quality samples collected were analyzed according to the list in Table II.C-5 if a sufficient quantity of water was available. This table was developed based on general guidelines given in the Colorado Water Quality Control Act and was later approved by the Colorado Mined Land Reclamation Board. Analytical methods utilized in the field and in the laboratory are summarized in Attachment A. Field analyses were completed immediately upon sample collection. Samples were preserved for later laboratory analysis according to methods outlined by the American Public Health Association et al. (1979). Attachment B contains the results of chemical analyses of surface water samples collected within the general area during the baseline period. Permit Renewal #3 (Rev. 8/99) II.C-22