When construction is to be performed over an extended period of time, but large quantities of material are to be purchased by the contractor at the beginning of the project (e.g., cable for URD installations), the borrower may allow alternative bids providing for payment to the contractor of 90 percent of the cost of such materials within 30 days of delivery of those materials at the job site. The borrower will retain the right to award the contract with or without the alternative payment provision, however, the contract still must be awarded on the basis of the lowest evaluated responsive bid for the alternative accepted.