Exhibit 10.55
Summary of Certain Executive Officer and Director Compensation Arrangements
Named Executive Officer Salary and Bonus Information
The following table presents the base salaries as of February 18, 2011 of our
named executive officers serving as executive officers as of December 31, 2010.

          Name   Salary  
Louis A. Raspino
  $ 950,000  
Imran Toufeeq
  $ 520,000  
W. Gregory Looser
  $ 445,000  
Brian C. Voegele
  $ 440,000  
Kevin C. Robert
  $ 375,000  
Lonnie D. Bane
  $ 370,000  

Under our annual incentive compensation plan for 2010, bonuses for executive
officers will be paid in 2011 based on the level of achievement of specific
objectives established by our Compensation Committee. The objectives under the
plan for 2010 (with target weight) consist of earnings per share (25%), control
of operating and general and administrative expense (15%), operating efficiency
(10%), free cash flow (20%), safety performance on a company-wide basis (10%),
and personal performance goals (20%). Target bonuses payable for 2010 as a
percentage of base salary for the persons named above are as follows:
Mr. Raspino—100%; Mr. Toufeeq—70%; Mr. Looser—65%; Mr. Voegele—65%;
Mr. Robert—60% and Mr. Bane—60%. The maximum bonus equals two times the target
bonus.
Nonemployee Director Fees
The annual retainer for the chairman of the board is $180,000 and for each other
director who is not an employee of our company is $50,000. We pay a fee of
$2,000 for each board and committee meeting attended. For committee meetings,
the fee is payable to all nonemployee directors participating, regardless of
committee membership, except to a director who is not a member of the committee
that does not receive the advance materials, if any, circulated to the committee
members. In addition, the chairman of the Audit Committee receives an annual fee
of $15,000; the chairman of the Compensation Committee receives an annual fee of
$15,000; and the chairman of the Nominating and Corporate Governance Committee
receives an annual fee of $10,000. Directors who are employees receive no
additional compensation for serving on the board of directors or its committees.