1. Short title This Act may be cited as the Blue Water Navy Vietnam Veterans Act of 2019 . 2. Clarification of presumptions of exposure for veterans who served in vicinity of Republic of Vietnam (a) In general Chapter 11 of title 38, United States Code, is amended by inserting after section 1116 the following new section: 1116A. Presumptions of service connection for veterans who served offshore of the Republic of Vietnam (a) Service connection For the purposes of section 1110 of this title, and subject to section 1113 of this title, a disease covered by section 1116 of this title becoming manifest as specified in that section in a veteran who, during active military, naval, or air service, served offshore of the Republic of Vietnam during the period beginning on January 9, 1962, and ending on May 7, 1975, shall be considered to have been incurred in or aggravated by such service, notwithstanding that there is no record of evidence of such disease during the period of such service. (b) Exposure A veteran who, during active military, naval, or air service, served offshore of the Republic of Vietnam during the period beginning on January 9, 1962, and ending on May 7, 1975, 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. (c) Effective date of award (1) Except as provided by paragraph (2), the effective date of an award under this section shall be determined in accordance with section 5110 of this title. (2) (A) Notwithstanding subsection (g) of section 5110 of this title, the Secretary shall determine the effective date of an award based on a claim under this section for an individual described in subparagraph (B) by treating the date on which the individual filed the prior claim specified in clause (i) of such subparagraph as the date on which the individual filed the claim so awarded under this section. (B) An individual described in this subparagraph is a