<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
REGISTRANT'S REPORT ON FORM 10-Q FOR THE SIX-MONTH PERIOD ENDED JUNE 30, 1997
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               JUN-30-1997
<CASH>                                       1,690,810
<SECURITIES>                                         0
<RECEIVABLES>                               14,631,745
<ALLOWANCES>                                   155,249
<INVENTORY>                                    440,283
<CURRENT-ASSETS>                            20,051,239
<PP&E>                                     106,363,113
<DEPRECIATION>                              27,265,692
<TOTAL-ASSETS>                             101,919,026
<CURRENT-LIABILITIES>                       19,970,399
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        93,589
<OTHER-SE>                                  47,482,792
<TOTAL-LIABILITY-AND-EQUITY>               101,919,026
<SALES>                                     62,739,287
<TOTAL-REVENUES>                            62,739,287
<CGS>                                                0
<TOTAL-COSTS>                               56,914,804
<OTHER-EXPENSES>                               576,376
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                             538,211
<INCOME-PRETAX>                              5,248,107
<INCOME-TAX>                                 2,041,514
<INCOME-CONTINUING>                                  0
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                 3,206,593
<EPS-PRIMARY>                                      .34
<EPS-DILUTED>                                      .34