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SHADWELL After Being Relfloated
MDSU Divers Isolating Leaks
the stern gate cofferdam was being fabricated,
the main body of Company 2-2
arrived on station. To ensure both contractors
and MDSU personnel had clear
tasking, MDSU was tasked with diving/
patching, and contractors were tasked
with continuing pumping operations.
Because SHADWELL had been used
for so many tests, her piping systems and
hull penetrations had been modified several
times over the years. The unmapped
piping and hull penetrations presented
many unique challenges to the divers
as they worked to discover and isolate
leaks. Another challenge the divers faced
was the material condition of the hull.
As patches and DC plugs were used to
isolate leaks, the corroding metal around
the patches frequently failed, requiring
new, larger patches to be installed. The
most challenging leak proved to be the
gap between the lower edge of the stern
gate and the top of the well deck. Divers
ultimately used bintsuke and rolled
up fire blankets that were cut to length in
order to seal the lower stern gate leaks.
Using 13 dives and nearly 20 hours of
bottom time, MDSU divers fabricated
and installed 4 major stern gate patches,
4 box patches, 10 DC plugs, and numer-
Initial POSSE Model
Burnt Diesel Fuel in Well Deck
ous soft patches
with epoxy reinforcement.
With the
leaks patched
and pumps installed,
the salvage
pumps were started with
a capacity in excess of 20,000
GPM. The largest pumps (2, 12-
inch pumps) were placed in the
well deck, three 6-inch pumps
were placed in the engineering
spaces and midbody ballast tanks,
and four more maneuverable 3
-inch salvage pumps were placed
in spaces and tanks fwd of FR 26.
After three full days of
pumping the SHADWELL
was refloated with minimal list
and was trimming aft as expected.
Pumping operations
continued for an additional day
to even the trim and place the
ship in an acceptable ballast condition.
The refloating of the EX-USS
SHADWELL was an great example
of how salvage operations can be conducted
using both military and civilian
salvors. In addition to being a successful
salvage operation, it was an
excellent learning opportunity and
provided a platform for knowledge
sharing between the organizations.
LCDR Eric Brege, P.E. is currently serving
as Assistant for Salvage at NAVSEA 00C..
January 2016 22