During the Deepwater Horizon BP oil spill response, thousands of 20 to 70-pound Danforth anchors were deployed to keep containment boom in place. After retrieval of the boom in areas where no containable oil posed a threat to the shoreline, it was discovered that some of the anchors were not accounted for various reasons such as storms. In addition, some anchors were solidly embedded in the sediment, and could not be recovered by teams retrieving boom.
A typical Danforth Anchor
The first phase of the program to remove these anchors will involve controlled testing by experienced underwater salvage teams. Crews will place anchors in a selected area and then search for them to find the best procedures and equipment for locating and removing the anchors. Using the best methods developed under these tests, crews will then transition into the second phase, which involves locating and removing the orphaned anchors deployed as part of the oil spill response in select areas of St. Bernard Parish.
If phase two recovery operations are successful in St. Bernard Parish, phase three of the plan will begin, which involves expanding removal operations to include all of the waters in Louisiana affected by the Deepwater Horizon BP oil spill.
“The federal government team that continues to oversee this response is committed to ensuring that BP uses a safe and proven method to find and remove orphan anchors so that teams do not break submerged pipelines in the area or further harm fragile ecosystems by causing erosion,” said Capt. Lincoln Stroh, Federal On-Scene Coordinator.
“Teams cannot simply drag the waterways with a hook or trawl due to the risk of breaking a pipeline or causing massive erosion. The program requires BP to undertake careful planning to ensure there is no environmental damage or destruction to existing pipelines and infrastructure.”
When laying boom, response crews used Danforth anchors, which embed in the sediment and collapse flat when not in use. This type of anchor does not protrude above the sediment like North Hill anchors. When the boom was retrieved, every anchor that could be recovered by the boom teams was safely removed
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