<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from the
September 30, 1997 quarterly consolidated financial statements and is
qualified in its entirely by reference to such finanical statements.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               SEP-30-1997
<CASH>                                           7,858
<SECURITIES>                                         0
<RECEIVABLES>                                   88,436
<ALLOWANCES>                                     1,837
<INVENTORY>                                      2,518
<CURRENT-ASSETS>                               120,619
<PP&E>                                         679,690
<DEPRECIATION>                                 217,574
<TOTAL-ASSETS>                                 584,581
<CURRENT-LIABILITIES>                           89,632
<BONDS>                                        212,431
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                           314
<OTHER-SE>                                     224,449
<TOTAL-LIABILITY-AND-EQUITY>                   584,581
<SALES>                                              0
<TOTAL-REVENUES>                               645,899
<CGS>                                                0
<TOTAL-COSTS>                                  606,940
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0<F1>
<INTEREST-EXPENSE>                              12,265
<INCOME-PRETAX>                                 26,873
<INCOME-TAX>                                    10,534
<INCOME-CONTINUING>                             16,339
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    16,339
<EPS-PRIMARY>                                      .52
<EPS-DILUTED>                                      .52
<FN>
<F1>Provision for Doubtful accounts included in costs and expenses applicable
to revenues.
</FN>