[Code of Federal Regulations] [Title 40, Volume 31] [Revised as of July 1, 2007] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR1502.21] [Page 880-881] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER V--COUNCIL ON ENVIRONMENTAL QUALITY PART 1502_ENVIRONMENTAL IMPACT STATEMENT--Table of Contents Sec. 1502.21 Incorporation by reference. Agencies shall incorporate material into an environmental impact statement by reference when the effect will be to cut down on bulk without impeding agency and public review of the action. The incorporated material shall be cited in the statement and its content briefly described. No material [[Page 881]] may be incorporated by reference unless it is reasonably available for inspection by potentially interested persons within the time allowed for comment. Material based on proprietary data which is itself not available for review and comment shall not be incorporated by reference.