H.R. 3684 would provide budget authority over the 2022-2026 period for the Department of Transportation (DOT) to continue operating programs funded from the Highway Trust Fund. The bill also would authorize the appropriation of funds for rail programs and certain other transportation programs administered by DOT and other federal agencies.
Historically, the contract authority provided in transportation legislation has been controlled by limitations on obligations contained in annual appropriation acts. CBO expects that the practice would continue under H.R. 3684; thus, CBO's estimate of mandatory outlays under the bill are significantly lower than the contract authority provided. For more information on the split budgetary classification of surface transportation programs funded from the Highway Trust Fund see Congressional Budget Office, The Highway Trust Fund and the Treatment of Surface Transportation Programs in the Federal Budget (June 2014), www.cbo.gov/publication/45416
In addition, H.R. 3684 would authorize appropriations for the Environmental Protection Agency (EPA) to fund new and existing grant programs aimed at improving water quality and access. Finally, the bill also would direct EPA to issue national primary drinking water regulations, which would establish legally enforceable limits on concentrations of certain perfluoroalkyl and polyfluoroalkyl substances (PFAS) and other substances in drinking water. CBO has not prepared an estimate of the discretionary costs of the bill.