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<br />O~~1~3 <br />v~.J _..........,;,.. t, <br /> <br />Table 4. Road-runoff sampling sites <br /> <br />[eRD, Clear Creek road ditch; GRD, Geneva Creek road ditch; identification nwnber is the latitude and longitude of the site with a two-digit sequence <br />nwnber at the end; see figure 4 for site location] <br /> <br />Site <br />number <br />CRDI <br />CRD2 <br />CRD3 <br />CRD4 <br />CRD5 <br />CRD6 <br />GRDl <br />GRD2 <br />GRD3 <br />GRD4 <br />GRD5 <br /> <br />U.S. Geological Survey <br />Identl'lcetlon number <br />393612105423800 <br />393602105423000 <br />393643105430200 <br />393643105425200 <br />393859105422700 <br />394036105415900 <br />393516105430700 <br />393506105430600 <br />393309105430200 <br />393244105430800 <br />393152105434700 <br /> <br />Site <br />name <br />Road ditch below Guanella Pass, Colorado <br />Road ditch near Guanella Pass, Colorado <br />Road ditch at Naylor Creek near Georgetown. Colorado <br />Road ditch above Lower Cabin Creek Reservoir near Georgetown, Colorado <br />Road ditch above Clear Lake Campground near Georgetown. Colorado <br />Road ditch below Green Lake near Georgetown. Colorado <br />Road ditch near Duck Lake near Grant, Colorado <br />Road ditch above Duck Lake near Grant, Colorado <br />Road ditch near Geneva Mountain near Grant, Colorado <br />Road ditch below Duck Lake. Colorado <br />Road ditch below Mill Gulch near Grant, Colorado <br /> <br />Ground-Water Sampling <br /> <br />Eight ground-water samples were collected in <br />the study area. Five of the samples were collected <br />from drinking-water hand pumps located in Forest <br />Service campgrounds and picnic areas. The remaining <br />three samples were collected from surface springs in <br />the study area, Sampling sites are listed in table 5 and <br />shown in figure 5. <br />Water from hand pumps was monitored for <br />water temperature and specific conductance during <br />pumping. When water temperature and specific <br />conductance stabilized. usually after IO or 15 minutes <br />of pumping, samples were collected at the outlet of <br />the pump mechanism. Samples for inorganic analyses <br />were pumped directly into the churn at the hand- <br />pumped sites or dipped with a polyethylene bottle <br />and transferred to the churn at the spring sites. <br />Samples for total organic carbon and dissolved <br />organic carbon analyses were collected directly in <br />baked amber glass bottles. <br />Field measurements of specific conductance, <br />water temperature, dissolved oxygen. and barometric <br />pressure were made onsite (M.A. Sylvester and <br />others. U.S. Geological Survey, unpub. data. 1990). <br />Turbidity and pH were measured from samples taken <br />from the churn splitter. Samples for analyses of <br />inorganic water-quality constituents were processed <br />and preserved as described for stream samples (Ward <br />and Harr. 1990). Samples for total and dissolved <br />organic carbon analyses were processed and preserved <br />as described for stream samples (Ward and Harr. 1990). <br /> <br />Lake/Reservoir Sampling <br /> <br />Four lakes/reservoirs were sampled in the study <br />area. The deepest location in the water body was <br />determined for sampling using a depth finder from <br />a boat. Sampling sites are listed in table 6 and shown <br />in figure 6. A multiparameter water-quality probe <br />that measured water temperature, specific conduc- <br />tance, pH, and dissolved oxygen was used to <br />determine a profile of those parameters with depth. <br />The transparency of the water was determined with <br />a Secchi disk. <br />Samples for inorganic and organic carbon <br />analyses were collected just below the surface and just <br />above the bottom using a Van Dom point sampler <br />(horizontal PVC cylinder with end seals triggered by <br />surface messenger) lowered on a cable and triggered <br />from the surface to trap water from a specific depth. <br />Field measurements of water temperature, specific <br />conductance. barometric pressure, and dissolved <br />oxygen for the surface and bottom samples were <br />determined from the profile measurements. Sample <br />water for inorganic analyses was transferred to clean, <br />acid-rinsed, deionized-water-rinsed, polyethylene <br />containers. Samples were transferred to a churn <br />splitter and then processed and preserved as described <br />for stream samples (Ward and Harr. 1990). Sample <br />water for carbon analysis was transferred to baked <br />glass containers at the surface and then processed and <br />preserved as described for stream samples (Ward and <br />Harr, 1990). <br /> <br /> <br />METHODS OF DATA COLLECTION AND ANALYSIS 11 <br />