* Rig's chief mechanic testifies to federal investigators
* BP employee said 'This is how it's going to be'- witness
* BP probe says 'fundamental mistake' may have been made
By Chris Baltimore
HOUSTON, May 26 Before rig workers aboard a
doomed drilling platform performed a procedure that BP Plc says
may have been a "fundamental mistake," there was a "skirmish"
between BP and Transocean staff about whether to proceed, the
rig's chief mechanic told federal investigators on Wednesday.
Around 9:53 p.m. CDT on April 20 (0253 GMT on April 21),
Swiss-based Transocean Ltd's (RIGN.S) (RIG.N) Deepwater Horizon
rig exploded while it was drilling a well a mile (1.6 km)
beneath the Gulf of Mexico under contract for London-based BP
Plc (BP.L). Eleven rig workers are presumed dead.
The Transocean mechanic's account could give the company
more ammunition in its verbal battle with BP to assign blame
for the disaster, which caused what is likely the biggest oil
spill in U.S. history.
Around noon, rig workers met in a room adjacent to the
rig's galley and "there was a slight argument that took place
and a difference of opinions," said Douglas Brown, the rig's
chief mechanic, speaking to a federal board of investigators in
Brown said "a skirmish" took place between "the company
man" from BP -- whose name he said he did not know -- and three
"The company man was basically saying, 'Well this is how
it's going to be,'" and Transocean rig workers "reluctantly
agreed," Brown said.
The argument concerned "displacing the riser," Brown said,
a reference to a decision made by rig personnel to remove heavy
drilling mud from the drill pipe and replace it with water, in
an attempt to wrap up drilling operations and plug the well
Drilling mud is a mixture of synthetic ingredients that is
pumped into the well to exert downward pressure and prevent a
column of oil and gas from rushing up the pipe.
Because water is lighter and less dense than mud, the
procedure allowed a flood of flammable methane gas to surge up
the drill pipe, which ignited and led to a catastrophic fire,
according to documents from the House of Representatives Energy
and Commerce Committee.
Congressional investigators say BP and Transocean made a
decision late on April 20 to begin removing mud from within the
drill pipe despite pressure tests from within the well that a
BP official described as "not satisfactory" and
Earlier in the day, well pressure tests showed an imbalance
between the drill pipe choke and kill lines running from the
drill deck to the blowout preventer. The pressure in the drill
pipe was 1,400 pounds per square inch, while the choke and kill
lines read zero PSI, according to BP documents gathered by the
House Energy and Commerce Committee.
In BP's internal investigation, made public by the
committee, BP said it might have been a "fundamental mistake"
to continue with the procedure because there was an "indication
of a very large abnormality."
As methane surged up the drill pipe and enveloped the rig,
Brown said, a loud hiss of gas escaped from the well, which set
off a stream of alarms.
"Gas alarms just kept piling up on top of each other more
and more and more," Brown said. The rig was hit by a power
blackout, and the explosion came soon after, he said.
"The first explosion basically threw me up against the
control panel that I was standing in front of," Brown said.
As Brown raced to reach the rig's lifeboats, "it was just
complete mayhem, chaos, people were scared, they were crying,"
The rig worker taking a muster of workers boarding the
lifeboat, a man that Brown said he had known for nine years,
did not recognize him.
"This is a man that has known me for nine years and he
cannot even remember my name," Brown said.
"It was just completely chaotic and nobody was really
paying attention in my opinion," Brown said. "They were more
concerned about just getting off the rig - escaping."
(Reporting by Chris Baltimore; editing by Mary Milliken and