<ARTICLE> 5
<MULTIPLIER> 1,000
       
                                        
<PERIOD-TYPE>                              3-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-END>                               MAR-31-1999
<CASH>                                           1,595
<SECURITIES>                                         0
<RECEIVABLES>                                   34,162
<ALLOWANCES>                                         0
<INVENTORY>                                     17,262
<CURRENT-ASSETS>                                57,871
<PP&E>                                       1,035,978
<DEPRECIATION>                                (489,119)
<TOTAL-ASSETS>                                 629,598
<CURRENT-LIABILITIES>                           54,827
<BONDS>                                        255,700
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0    
<COMMON>                                         2,774
<OTHER-SE>                                     190,845
<TOTAL-LIABILITY-AND-EQUITY>                   629,598
<SALES>                                         76,075
<TOTAL-REVENUES>                                78,220
<CGS>                                                0
<TOTAL-COSTS>                                   58,291
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                               4,278
<INCOME-PRETAX>                                 14,971
<INCOME-TAX>                                     5,839
<INCOME-CONTINUING>                              9,132
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     9,132
<EPS-PRIMARY>                                     0.37
<EPS-DILUTED>                                     0.37
<FN>
The information has been prepared in accordance with SFAS No. 128.
Basic and dilted EPS have been entered in place of primary and fully diluted,
respectively.
</FN>