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URS Operating Services, Inc. START2, EPA Region VIII Contract No. 6R-W.00-I 18 Battle Mountain Gold -Trip Repon Revision: 0 Dale: 92000 Page 3 of 12 The analytical data presented in Table 2 for the two samples of the stagnant water collected from the abandoned channels of the Rito Seco (RSR-6A and RSR-6B) show higher concentrations of aluminum, arsenic, barium, beryllium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, nickel, potassium, sodium, vanadium, and zinc than the water from the main channel of the Rito Seco. The concentrations of certain metals in sample RSR-06B, which had a precipitate on [he surfac: of the sediment were higher than those found in the most downstream RSR-06A (Table 2, Photos 1 and 2). The Colorado MCLs for barium and nickel (results in bold) are exceeded in sample RSR-06B. The sample collected from the bog area seep (BAS) has detections of aluminum, barium, calcium, iron, magnesium, manganese, potassium, selenium, and sodium that are greater than those found in the Rito Seco near where the seep water enters the stream (Table 2). Mercury and cyanide were not detected in the sample. Flow from [he bog seep was estimated to be approximately one third liter per minute. QUALITY ASSURANCE AND QUALITY CONTROL The analytical results ofthe duplicate sample (RS-10) collected with sample RS-Ol indicate good correlation between sample results for the QA/QC sample (Table 2). The Data Validation Report is attached as Appendix B. The report states that laboratory blank contamination required the qualification of some analytical results for aluminum, arsenic, cobalt, copper, lead, potassium, thallium, and zinc. Some results for lead were also qualified because of spike recovery issues. CONCLUSIONS Six locations were sampled along the Rico Seco in [he vicinity of the Battle Mountain facility. All samples were grab samples for total metals (TAL) analysis collected from locations requesb:d by the local representative. Samples collected along the Rito Seco showed a gradual increase in metal s concentrations in the stream water as the Rito Seco flowed past the facility. The two most downstream locttions were from stagnant water in abandoned channels of the Rito Seco and produced elevated concentratitms of metals, of particular barium and nickel which were above the Colorado State MCLs. The sample collec ed from the seep at [he bog produced elevated concentrations of calcium, magnesium, and sodium. 75-00967.00 P:\StartPBattle Mountain Gold\trip_repon.wyd:bas