This chapter establishes the rules and procedures for using previously prepared environmental documents, National Environmental Policy Act (NEPA) document, supplemental environmental impact statements (SEIS), addenda to environmental documents, adoption of environmental documents, incorporating existing studies and material by reference and combining documents. The intent is to avoid duplication and unnecessary paperwork by utilizing existing information within the context of SEPA review where pertinent to a proposal. [Ord. 2512 § 1, 1984; Code 1970 § 23.06.010.]