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3. SEDIMENT POND INSPECTION REPORTS AND SEDIMENT SURVEYS <br />• Requirement <br />"Tn order to clarify specific regulatory obligations regazding sediment pond certification and maintenance <br />... , the permittce has wmmitted to: <br />A. Inspect the condition of all sediment pond embanlanents, spillways and dewatering devices <br />quarterly... <br />The information will be submitted to the Division in an annual report.." Excerpted in part from Colowvo <br />Findines and Proposed Decision to Aoorove Pemrit. File No. C-019-81, September 28, 1982. <br />Additionally, Technical Revision No. 26 approved March 18, 1994, states: <br />"Survey measurements of sediment accuruulations will be conducted biannually for discharge points 003, <br />004, and 007 and arty new sediment ponds and every third year for 001, 002, 005, and 006." Excerpted <br />from Colowvo Permit C-81-019. Volume 1. Page 4.05-6. <br />Response <br />The Sediment Pond Inspection Reports are found in Exhibit 3 which satisfies requirement A above. The <br />reports indicate the ponds are operating in accordance with certified designs. All embanlanents, <br />spillways, and other outlet stmctures are in good operating wndition. Due to corrosion the Streeter pond <br />• outlet pipe had developed a small leak. The pipe and headgate were replaced. The new headgate <br />developed a small leak, (less than .25 gaUmin) at the interface of the plate and seal which appears to be <br />within the manufacturer's specification for the device. Sampling of the discharge continues until a <br />variance can be obtained for such small flows. <br />The East Taylor pond had a small leak due to settling of the new outlet structure. The leak, located where <br />the headgate mounts onto the outlet culvert, was 5xed during the summer by the addition of additional <br />sealant and additional retaining bolts. The Streeter pond, Gulch A. Pond, and the Washbay Sediment <br />sump were dredged during 1996. Table 1 on the following page summarizes Ure sediment volume status <br />for all ponds and shows when the next sediment survey is required. <br />Then; is no evidence of potential failure at any of the ponds. >n addition, the steel markers located on <br />the hillside above and south of the West Pit Pond indicates no further evidence of instability. Colowyo <br />is also in the process of redesigning the ponds as "treatment" structures rather than "containment <br />• structures. <br />7 <br />