National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling pdf
Commissioners
Bob Graham, Co-Chair, William K. Reilly, Co-Chair, Frances Beinecke, Donald F.,Boesch,Terry D. Garcia, Cherry A. Murray, Fran Ulmer, Richard Lazarus Executive Director
To: Bob Graham, Co-Chair, William K. Reilly, Co-Chair, Frances Beinecke, Donald F. Boesch, Terry D. Garcia, Cherry A. Murray, Fran Ulmer
October 28, 2010
Dear Commissioners,
We write to report the results of cement testing that we have recently
conducted and several conclusions we have reached based on that testing
and documents subsequently provided to us by Halliburton. We wanted to
report these results immediately to facilitate your consideration of their
implications for offshore drilling safety.

We have known for some time that the cement used to secure the
production casing and isolate the hydrocarbon zone at the bottom of the
Macondo well must have failed in some manner. That cement should have
prevented hydrocarbons from entering the well. For a variety of technical
reasons that we will explain at the upcoming hearing, BP cemented the
well with a nitrogen foam cement recommended and supplied by
Halliburton. Halliburton generated the nitrogen foam cement by injecting
high pressure nitrogen into a base cement slurry as it pumped that slurry
into the well.

We asked Halliburton to supply us samples of materials like those actually
used at the Macondo well so that we could investigate issues surrounding
the cement failure. Halliburton provided us off-the-shelf cement and
additive materials used at the Macondo well from their stock. Although
these materials did not come from the specific batches used at the Macondo
well, they are in all other ways identical in composition to the slurry used
there.

Fourth Floor One Thomas Circle, NW Washington, D.C. 20005 • Tel (202) 254-2600 • Fax (202) 254-2617 • www.01ISpIlICommlaslon.gov
National Commission on the
BP DEEPWATER HORIZON OIL SPILL
AND OFFSHORE DRILLING

Chevron agreed as a public service to test the cement slurry on behalf of
the Commission. Chevron employs some of the industry's most respected
cement experts, and it maintains a state-of-the art cement testing facility
in Houston, Texas. Halliburton agreed that the Chevron lab was highly
qualified for this work.

We attach Chevron's report of its laboratory tests, and we have invited one
of its experts to discuss that report with you at the public hearing on
November 9.

Chevron's report states, among other things, that its lab personnel were
unable to generate stable foam cement in the laboratory using the
materials provided by Halliburton and available design information
regarding the slurry used at the Macondo well. Although laboratory foam
stability tests cannot replicate field conditions perfectly, these data
strongly suggest that the foam cement used at Macondo was unstable.
This may have contributed to the blowout.

Commissioners
Bob Graham, Co-Chair
William K. Reilly, Co-Chair
Frances Beinecke
Donald F. Boesch
Terry D. Garcia
Cherry A. Murray
Fran Ulmer
Richard Lazarus
Executive Director

Halliburton has stated publicly that it tested the Macondo cement before
pumping it on April 19 th and 20th, and that its tests indicated the cement
would be stable. When Chevron informed us of the preliminary results of
its tests, we asked Halliburton to give us all of the data from all tests it
had run on the Macondo cement slurry.

The documents provided to us by Halliburton show, among other things,
that its personnel conducted at least four foam stability tests relevant to
the Macondo cement slurry. The first two tests were conducted in
February 2010 using different well design parameters and a slightly
different slurry recipe than was finally used. Both tests indicated that this
foam slurry design was unstable.

Halliburton provided data from one of the two February tests to BP in an
email dated March 8, 2010. The data appeared in a technical report along
with other information. There is no indication that Halliburton
highlighted to BP the significance of the foam stability data or that BP
personnel raised any questions about it. There is no indication that
Halliburton provided the data from the other February test to BP.

Fourth Floor One Thomas Circle, NW Washington, D.C. 20005 • Tel (202) 254-2600 • Fax (202) 254-2617 • viww.011SpIlICommisslon.gov
National Commission on the
BP DEEPWATER HORIZON OIL SPILL
AND OFFSHORE DRILLING
Commissioners
Bob Graham, Co-Chair
William K. Reilly, Co-Chair
Frances Beinecke
Donald F. Boesch
Terry D. Garcia
Cherry A. Murray
Fran Ulmer
Richard Lazarus
Executive Director

Halliburton conducted two additional foam stability tests in April, this
time using the actual recipe and design poured at the Macondo well. We
believe that its personnel conducted the first of these two tests on or about
April 13, seven days before the blowout Lab personnel used slightly
different lab protocols than they had used in February. Although there are
some indications that lab personnel may have conducted this test
improperly, it once again indicated that the foam slurry design was
unstable. The results of this test were reported internally within
Halliburton by at least April 17, though it appears that Halliburton never
provided the data to BP.

It appears that Halliburton personnel began a second April foam stability
test shortly after receiving the unfavorable results from the first April test.
Halliburton personnel again modified the testing procedure, and this time
— for the first time — the data indicated the foam slurry design would be
stable. We are not yet certain when Halliburton reported this data
internally or whether the test was even complete prior to the time the
cement job was poured at the Macondo well. Halliburton reported this
data to BP after the blowout.

Taken together, these documents lead us to believe that:
Only one of the four tests discussed above that Halliburton ran
on the various slurry designs for the final cement job at the
Macondo well indicated that the slurry design would be stable;
Halliburton may not have had—and BP did not have—the
results of that test before the evening of April 19, meaning that
the cement job may have been pumped without any lab results
indicating that the foam cement slurry would be stable;

(3)
Halliburton and BP both had results in March showing that a
very similar foam slurry design to the one actually pumped at
the Macondo well would be unstable, but neither acted upon
that data; and
Fourth Floor One Thomas Circle, NW Washington, D.C. 20005 • Tel (202) 254-2600 • Fax (202) 254-2617 • vAnconspincommission.gov
National Commission on the
BP DEEPWATER HORIZON OIL SPILL
AND OFFSHORE DRILLING

(4) Halliburton (and perhaps BP) should have considered
redesigning the foam slurry before pumping it at the Macondo
well.

Finally, we want to emphasize that even if our concerns regarding the
foam slurry design at Macondo are well founded, the story of the blowout
does not turn solely on the quality of the Macondo cement job. Cementing
wells is a complex endeavor and industry experts inform us that cementing
failures are not uncommon even in the best of circumstances. Because it
may be anticipated that a particular cement job may be faulty, the oil
industry has developed tests, such as the negative pressure test and
cement evaluation logs, to identify cementing failures. It has also
developed methods to remedy deficient cement jobs.

Commissioners
Bob Graham, Co-Chair
William K. Reilly, Co-Chair
Frances Beinecke
Donald F. Boesch
Terry D. Garcia
Cherry A. Murray
Fran Ulmer
Richard Lazarus
Executive Director

BP and/or Transocean personnel misinterpreted or chose not to conduct
such tests at the Macondo well.
Sincerely,
/ s / Fred H. Bartlit
Fred H. Bartlit, Jr.
Sean C. Grimsley
Sambhav N Sankar
Fourth Floor One Thomas Circle, NW Washington, D.C. 20005 • Tel (202) 254-2600 • Fax (202) 254-2617 • tinvw.011Sp111CommIsslon.gov