<ARTICLE>           5
<LEGEND>            THIS SCHEDULE CONTAINS SUMMARY FINANCIAL
                    INFORMATION EXTRACTED FROM THE COMPANY'S 
                    UNAUDITED FINANCIAL STATEMENTS AS OF AND 
                    FOR THE PERIOD ENDING JUNE 30, 1997, AND 
                    IS QUALIFIED IN ITS ENTIRETY BY REFERENCE
                    TO SUCH FINANCIAL STATEMENTS 
<MULTIPLIER>        1,000
<FISCAL-YEAR-END>   DEC-31-1997
<PERIOD-END>        JUN-30-1997
<PERIOD-TYPE>       6-MOS


<CASH>                                                   920
<SECURITIES>                                               0
<RECEIVABLES>                                         63,589
<ALLOWANCES>                                               0
<INVENTORY>                                           18,206
<CURRENT-ASSETS>                                      94,610
<PP&E>                                               309,327
<DEPRECIATION>                                       135,460
<TOTAL-ASSETS>                                       322,945
<CURRENT-LIABILITIES>                                 57,100
<BONDS>                                                    0
<COMMON>                                              18,128
<PREFERRED-MANDATORY>                                      0
<PREFERRED>                                                0
<OTHER-SE>                                           103,852
<TOTAL-LIABILITY-AND-EQUITY>                         322,945
<SALES>                                              216,148
<TOTAL-REVENUES>                                     216,674
<CGS>                                                192,292
<TOTAL-COSTS>                                          6,223
<OTHER-EXPENSES>                                           0
<LOSS-PROVISION>                                           0
<INTEREST-EXPENSE>                                     2,717
<INCOME-PRETAX>                                       15,442
<INCOME-TAX>                                           5,637
<INCOME-CONTINUING>                                    9,805
<DISCONTINUED>                                             0
<EXTRAORDINARY>                                            0
<CHANGES>                                                  0
<NET-INCOME>                                           9,805
<EPS-PRIMARY>                                           0.54
<EPS-DILUTED>                                           0.54