36 CFR § 800.14(a)
Alternate procedures are a program alternative that allows federal agencies to streamline the Section 106 process by tailoring the process to the agency’s programs and decision-making process. Procedures, approved by the ACHP and adopted by the agency, substitute in whole or in part for the ACHP’s Section 106 regulations under Subpart B. The ACHP allows for flexible application of alternate procedures which can either be counterpart regulations of an agency or can include agency procedures that do not have to go through a formal rulemaking process.
Learn more in the Alternate Procedures Questions and Answers.