This regulation establishes time-limited tolerances for residues of phosphine resulting from the use of the rodenticide zinc phosphide in or on timothy (seed, forage, hay), alfalfa (forage, hay), and clover (forage, hay). This action is in response to EPA's granting of an emergency exemption under section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act authorizing use of the pesticide on timothy or timothy-alfalfa, clover stands in Washington. This regulation establishes a maximum permissible level for residues of phosphine in these food commodities pursuant to section 408(l)(6) of the Federal Food, Drug, and Cosmetic Act, as amended by the Food Quality Protection Act of 1996. The tolerances will expire and are revoked on February 1, 2000.