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<br />Conservation License (rev. 12/16) Page 20 of 23 License No. 23-108200 <br />B. Direct Pull: <br /> <br />1) This method is optional if the contractor determines it to be appropriate for the substrate <br />type, pile length, and structural integrity of the piling. Vibratory extractor must be <br />attempted first unless there is risk of greater disturbance of sediments. <br /> <br />2) Pilings are wrapped with a choker cable or chain that is attached at the top to a crane. <br />The crane pulls the piling directly upward, removing the piling from the sediment. <br /> <br />C. Clamshell Removal: <br /> <br />1) Broken and damaged pilings that cannot be removed by either the vibratory hammer or <br />direct pull may be removed with either a clamshell bucket or environmental clamshell. <br /> <br />2) A clamshell is a hinged steel apparatus that operates like a set of steel jaws. The bucket <br />is lowered from a crane and the jaws grasp the piling stub as the crane pulls up. <br /> <br />3) The size of the clamshell bucket shall be minimized to reduce turbidity during piling <br />removal. <br /> <br />4) The clamshell bucket shall be emptied of material onto a contained area on the barge <br />before it is lowered into the water. <br /> <br />D. Cutting: <br /> <br />1) Is required if the pile breaks at or near the existing substrate and cannot be removed by <br />other methods. <br /> <br />2) If a pile is broken or breaks during extraction, all of the methods listed below should be <br />used to cut the pile. <br /> <br />a. Piles located in intertidal and shallow subtidal areas that are less than -10 feet <br />deep MLLW shall be cut at least 2 feet below the mudline. <br /> <br />b. In subtidal areas that are greater than -10 feet deep MLLW, piles shall be cut at <br />least 1 foot below the mudline. <br /> <br />c. Piles shall be cut off at lowest practical tide condition and at slack water. This is <br />intended to reduce turbidity due to reduced flow and short water column through <br />which pile must be withdrawn. <br /> <br />d. No hydraulic jetting devices shall be used to move sediment away from piles. <br />Excavation of sediment in subtidal areas to expose broken piles shall be <br />accomplished by divers using hand tools. <br /> <br />Docusign Envelope ID: 9AF27A6B-A801-4DA1-8CF6-CC7F0385775B