Att A -Piling removal BMPs.pdf

42. Piling and Other Structure Removal includes the removal of untreated and chemically treated wood pilings, piers, vessels, boat docks, derelict fishing gear, as well as similar structures comprised of plastic, concrete, and other material. Pilings and other structures occur in estuaries, lakes, floodplains, and rivers, and are typically used in association with boat docks, structures, and other facilities.

a. When removing an intact pile

1. Install a floating surface boom to capture floating surface debris.

ii. To the extent possible, keep all equipment (e.g., bucket, steel cable, vibratory hammer) out of the water, grip piles above the waterline, and complete all work during low water and low current conditions.

111. Dislodge the piling with a vibratory hammer, whenever feasible. Never intentionally break a pile by twisting or bending.

iv. Slowly lift piles from the sediment and through the water column.

v. Place chemically-treated piles in a containment basin on a barge deck, pier, or shoreline without attempting to clean or remove any adhering sediment. A containment basin for the removed piles and any adhering sediment may be constructed of durable plastic sheeting with sidewalls supported by hay bales or another support structure to contain all sediment and return flow which may otherwise be directed back to the waterway.

vi. After piling removal, fill the holes left with clean, native sediments from the project area.

vii. Dispose of all removed piles, floating surface debris, any sediment spilled on work surfaces, and all containment supplies at a permitted upland disposal site.

b. When removing a broken pile

i. If a pile breaks above the surf ace of uncontaminated sediment, or less than

2 feet below the surface, make every attempt short of excavation to remove it entirely. If the pile cannot be removed without excavation, drive the pile deeper if possible.

11. If dredging is likely in the area of piling removal, use a GPS (global positioning device) to note the location of all broken piles for future use in site debris characterization.

43. Shellfish Bed/Nearshore Habitat Restoration may involve shellfish bed restoration, replacing shore line armoring, and providing beach nourishment. An example of a sustainable restoration action might include restoration of sediment input to a nearshore by removing bulkheads at historical feeder bluff sites, thereby allowing gradual and ongoing erosion/mass wasting of bluffs and L W recruitment, instead of one-time beach nourishment. This opinion does not cover projects where the sole objective is to protect upland property or to cap contaminants.

a. Shellfish bed restoration

i. Shell or other substance used for substrate enhancement will be procured from clean sources that do not deplete the existing supply of shell bottom.

Shells should be steam cleaned, left on dry land for a minimum of one month, or both, before placement in the aquatic environment. Shells from the local area should be used whenever possible.

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