U.S. NAVY SALVAGE REPORT DEEPWATER HORIZON ... - ESSM

Chapter 5: Operations
The VOSS crews faced various challenges during their time at sea. One of the biggest was the
amount of debris that was encountered at sea. The booms collected natural floating debris like
sea weed, grasses and jellyfish, oil displaced sea life such as sea cucumbers, and various
plastic and trash items. This material would overwhelm the grinder/macerators associated with
the weirs and had to be removed to maintain pump effectiveness. Figure 5-11 shows a weir type
skimmer pump being lifted from the Current Buster pocket for cleaning. While the pumps could
be serviced onboard, the debris in the pocket was more difficult to remove.
Figure 5-11. OSV JOHN COGHILL’s High Speed Current Buster weir pulled
from water to allow cleaning of debris which was clogging suction.
A number of solutions were developed but none of them resulted in simple, problem free
operations. Any time debris could be avoided through ship maneuvers, the ship did so. At night,
the debris was impossible to see, so at first light the crew set about the task of cleaning up from
the night before. A couple of solutions the crews employed to deal with the debris issues are
highlighted below.
• Fabricating a removable wire mesh screen to protect the inlet suction. This removable
screen needed to be hoisted out of the water for trash removal. It often was heavier than
could be man-lifted and a boom/hoist needed to be rigged.
• Raking up the debris manually – Figure 5-12 shows cleanup of the Class XI skimmer on
OSV RENE. On the Current Buster, which would not support crew as the Class XI would,
ESSM personnel would rig a set of boat hooks for dipping into the calming pocket and
removing trash.
5-12