<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from the
June 30, 2000 quarterly consolidated financial statements and is
qualified in its entirety by reference to such financial statements.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-2000
<PERIOD-START>                             JAN-01-2000
<PERIOD-END>                               JUN-30-2000
<CASH>                                           3,957
<SECURITIES>                                         0
<RECEIVABLES>                                  163,243
<ALLOWANCES>                                     3,662
<INVENTORY>                                      5,967
<CURRENT-ASSETS>                               205,027
<PP&E>                                         960,903
<DEPRECIATION>                                 334,553
<TOTAL-ASSETS>                                 834,893
<CURRENT-LIABILITIES>                          166,171
<BONDS>                                        248,801
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                           324
<OTHER-SE>                                     344,113
<TOTAL-LIABILITY-AND-EQUITY>                   834,893
<SALES>                                              0
<TOTAL-REVENUES>                               682,130
<CGS>                                                0
<TOTAL-COSTS>                                  620,589
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0<F1>
<INTEREST-EXPENSE>                               8,067
<INCOME-PRETAX>                                 53,095
<INCOME-TAX>                                    21,078
<INCOME-CONTINUING>                             32,017
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    32,017
<EPS-BASIC>                                        .99
<EPS-DILUTED>                                      .98
<FN>
<F1>Provision for Doubtful accounts included in costs and expenses
applicable to revenues.
</FN>