A veteran who, during active military, naval, or air service, served between April 1, 1968, and August 31, 1971, in a unit that, as determined by the Department of Defense, operated in or near the Korean DMZ in an area in which herbicides are known to have been applied during that period, shall be presumed to have been exposed during such service to an herbicide agent, unless there is affirmative evidence to establish that the veteran was not exposed to any such agent during that service. See also 38 CFR 3.814(c) (2).Regulations.gov Monetary allowance under 38 U.S.C. 1821 for an individual suffering from spina bifida who is a child of a veteran with covered service in Korea. Except as provided in Sec. 3.814(e), an award of the monetary allowance under 38 U.S.C. 1821 based on the existence of an individual suffering from spina bifida who is a child of a veteran with covered service in Korea will be effective from either the date of birth if claim is received within 1 year of that date, or the later of the date of claim or date entitlement arose, but not earlier than December 16, 2003.