United States, Sept. 16 -- SLSCO Ltd., Galveston, Texas, is awarded a $30,519,900 modification to a firm-fixed-price contract for construction of an aircraft parking apron and supporting facilities at Royal Australian Air Force Base, Darwin, Australia. The total cumulative face value of the contract is $490,841,516.The contract modification provides for an increase in estimated quantity for asbestos containing material encountered onsite. Work will be performed in Darwin, Australia, and is expected to complete by May 2028.Fiscal 2025 and 2026 military construction (Navy) funds in the amount of $10,028,333 and $20,491,567 are obligated at time of award and will not expire at the end of the current fiscal year. Naval Facilities Engineering Sy...