This regulation establishes a tolerance for residues of dimethenamid in or on horseradish. The Interregional Research Project No. 4 (IR-4) requested this tolerance under the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 1996 (FQPA). In addition, this regulatory action is part of the tolerance reassessment requirements of section 408(q) of FFDCA, 21 U.S.C. 346a(q), as amended by the FQPA of 1996. By law, EPA is required to reassess all tolerances in existence on August 2, 1996 by August 2006. This regulatory action will count towards this August 2006 deadline. This regulation establishes a maximum permissible level for residues of dimethenamid in this food commodity. EPA has previously published all relevant scientific conclusions and analysis related to this tolerance action. Due to an inadvertent oversight, a final rule published in the Federal Register on September 24, 2004, which outlined EPA action to establish several tolerances for residues of dimethenamid on various commodities, including horseradish, did not contain necessary information in a table to actually add the tolerance for dimethenamid residues on horseradish into 40 CFR 180.464. This action corrects that error.