C.R.S. § 8-72-102

(1) The director of the division has the power to adopt, amend, or rescind, in accordance with section 24-4-103 , C.R.S., reasonable and necessary rules relating to the administration of the “Colorado Employment Security Act” and governing hearings and proceedings under such act. (2) The director shall adopt rules establishing a procedure for an individual or employer filing a petition for review pursuant to section 8-74-106 (1)(a) or (1)(b) or an appeal pursuant to section 8-73-107 (1)(c)(I)(A), 8-74-103 (1), 8-74-104 (1), 8-76-113 (1) or (2), or 8-81-101 (4)(c), or an interested party presenting additional information pursuant to section 8-74-102 (1), to contest a determination by the director that the individual, employer, or interested party failed to comply with a deadline set forth in the applicable section by providing proof that the petition for review, appeal, or additional information was timely mailed.