Dept. of Trans.       SUPPLEMENTAL   Serial No.  Contract No.                           
                                          05-034-14-31  08-334844                       
                PROGRESS PAYMENT VOUCHER  %complete:   %time:                           
Location:                                  19%          23%                             
08-RIV-215-R37.7/43.9                    Federal Project:                               
08-RIV-91-20.3/21.6                                     ACNH-215-1(219)                 
08-RIV-60-11.5/13.7                             I-215-1(219)                            
                             ACNH-X065(80)                                              
Progress payment No. 13            Payment period ending: 01-31-05                      
WASHINGTON GROUP INTERNATIONAL                                                          
INC OBAYASHI CORPORATION A                                                              
JOINT VENTURE                                                                           
P O BOX 600                                                                             
HIGHLAND CA 92346                                                                       
Escrow No.  02171                                                                       
                                    Total Estimate   This Estimate                      
1. Contract Itms Without Mobil.      21,023,428.73      476,887.60                      
2.a. Extra Work                         999,076.10      -16,020.37                      
  b. Adjustment Comp.                    31,701.37            0.00                      
3. Materials on Hand                  1,702,336.03            0.00                      
4. Earned Subject to Retention       23,756,542.23      460,867.23                      
5. Mobilization                      13,757,298.71            0.00                      
6. Total Work Completed   35,811,504.91                                                 
7. Deductions                          -185,431.27            0.00                      
8. a.Contract Retentions             -2,375,654.22      -46,086.72                      
   b. Unsatisfactory Prog.                                                              
   c. Reduction after 95% Comp.                                                         
9. Total pay to Contractor           34,952,755.45      414,780.51                      
10. Reduction Amt to Escrow                                                             
11. Payment to Escrow     2,375,650.00                                                  
12. Net Pymt. this Estimate                             414,780.51