obsolete 4,6-dichloro-3-methylcatechol 1,2-dioxygenase activity (obsolete GO:0034936)
OBSOLETE. Catalysis of the reaction: 4,6-dichloro-3-methylcatechol + O2 = 3,5-dichloro-3-methyl-cis,cis-muconate + 2 H+.