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<br />West Taylor Pond Riser Pipe Leak Repair Procedure <br />August 27, 2010 <br />1. Acquire appropriate sealant from on-site stock (warehouse). <br />2. Collect proper NPDES sampling and shipping materials prior to <br />action. <br />3. Approximate window of 2-3 days when the reasonable <br />likelihood for precipitation is low. <br />4. Perform Take 5 procedure prior to approaching the riser/gate <br />valve structure. <br />5. Slowly open the gate valve to a maximum of % open position, <br />'/4 turn at a time and observe the flow that results. <br />6. An NPDES compliance sample and field measurements should <br />be drawn within 20 minutes of initialization of discharge to <br />ensure a representative sample is drawn while allowing for <br />proper and appropriate scouring and clearance of residue from <br />the pipe. <br />7. Observe drawdown of pond. <br />8. Once pond drawdown is completed, allow several hours for <br />any/all joints within the riser to dry. <br />9. Safely access the riser stand pipe and apply sealing compound <br />to all joints. Inspect all bolt assemblies for integrity and seal <br />them as well. Also inspect the gate valve for any signs of <br />damage, disrepair or lack of function. Complete any necessary <br />repairs. <br />10. Once sealant is applied, leave gate valve in the open position <br />for 48 hours to allow continuing inflow to pass through the pond <br />and give the sealant a chance to cure. <br />11. After 48 hours, close the gate valve. <br />12. Observe the discharge pipe outfall for evidence of flow <br />periodically as the pond level increases over time to confirm the <br />previous actions were successful. <br />13. Should this process fail to stop the leak, a camera probe will be <br />utilized to identify any buried areas of the discharge pipe that <br />may be compromised and contributing to the problem. The <br />Division will be consulted and any necessary approvals secured <br />prior to any further action that would affect the structure and <br />function of the pond by means of exposing the discharge pipe <br />under the embankment via excavation or other intrusive means.