[Code of Federal Regulations] [Title 45, Volume 3] [Revised as of October 1, 2002] From the U.S. Government Printing Office via GPO Access [CITE: 45CFR641.19] [Page 188] TITLE 45--PUBLIC WELFARE CHAPTER VI--NATIONAL SCIENCE FOUNDATION PART 641--ENVIRONMENTAL ASSESSMENT PROCEDURES FOR PROPOSED NATIONAL SCIENCE FOUNDATION ACTIONS IN ANTARCTICA--Table of Contents Sec. 641.19 Modification of environmental documents. The responsible official should revise or supplement an environmental document if there is a change in a proposed action that may have more than a minor or transitory effect on the antarctic environment, or if there are new circumstances or information that indicate the action may have impacts not anticipated in the original environmental document.