This regulation establishes a tolerance for residues of the new herbicide, (AC 263,222) (+)-2-[4,5-dihydro-4-methyl-4-(1- methylethyl)-5-oxo-1H-imidazol-2-yl]-5-methyl-3-pyridinecarboxylic acid applied as its ammonium salt and its metabolite (+)-2-[4,5- dihydro-4- methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-hydromethyl-3- pyridinecarboxylic acid both free and conjugated, in or on peanut nut meat at 0.1 ppm. The regulation to establish a maximum permissible level for the residues of the herbicide was requested in petitions submitted by American Cyanamid Company.