SECTION 13. Definitions applicable to Secs. 13 to 17

As used in this section and sections 14 through 17, inclusive, the following words shall have the following meanings:

''Base year valuation'', for each city and town, the valuation of state-owned land within the city or town as of January 1, 2017 as determined by the commissioner under this section.

''Base year per-acre land valuation'', for each city and town, the valuation per-acre of state-owned land as determined by the commissioner during the base year valuation of state-owned land under this section.

''Fair cash valuation'', for each city and town, the valuation of state-owned land located in the city or town as of January 1 and used to determine the reimbursement in lieu of taxes under section 17 for the fiscal year that begins the July 1 of the following year. The fair cash valuation as of January 1, 2019 shall equal the base year valuation, adjusted by the percentage, if any, by which such valuation has changed, as determined by the commissioner from the biennial equalized valuation reported for the city and town under sections 10 through 10C, inclusive, for January 1, 2018, plus the fair cash valuation of state owned land acquisitions and minus the fair cash valuation of state-owned land dispositions since the base year valuation. The fair cash valuation of any state-owned land acquisitions and dispositions within the city or town shall equal the product of the per-acre land valuation for the city or town times the number of acres of such state-owned land. Thereafter, the fair cash valuation as of any January 1 shall equal the fair cash valuation for the preceding January 1, adjusted in the year for which the commissioner is to establish a valuation under section 14 by the percentage, if any, by which such valuation has changed, as determined by the commissioner from the biennial equalized valuation for the preceding January 1, plus the fair cash valuation of state owned land acquisitions and minus the fair cash valuation of state-owned land dispositions during the preceding calendar year.

''Per-acre land valuation'', for each city and town, the per acre land valuation used to determine the fair cash valuation of state-owned land acquisitions and dispositions during any calendar year. The valuation as of January 1, 2019 shall equal the base year per acre land valuation, adjusted by the percentage, if any, by which such valuation has changed, as determined by the commissioner from the biennial equalized valuation reported for such city and town under sections 10 to 10C, inclusive, for January 1, 2018. Thereafter, the valuation shall equal the per acre land valuation last established, adjusted by the percentage, if any, by which such valuation has changed, as determined by the commissioner from the biennial equalized valuation for the January 1 preceding the year for which the commissioner is to establish a valuation under section 14. The valuation shall be used to determine the fair cash valuation of state-owned land acquisitions and dispositions for the year in which the commissioner makes such per-acre land valuation and the succeeding year, and until another such valuation is made.

''Reimbursement percentage'', for each city and town, the fair cash valuation percentage share of the annual appropriation made for reimbursements in lieu of taxes on state-owned land. The percentage shall be the fair cash valuation of the state-owned land within the city or town as of January 1 divided by the total fair cash valuation of all state-owned land as of January 1.

''State-owned land'' all land owned by the commonwealth as of January 1 and used for the purposes of a fish hatchery, game preserve or wild life sanctuary, a state military camp ground, the Soldiers' Home in Massachusetts, the Soldiers' Home in Holyoke, a state forest, the University of Massachusetts, or a public institution under the department of correction, the department of higher education, the department of mental health, the department of developmental services, the department of public health, the department of transitional assistance, or the department of youth services, land owned by the commonwealth known as the Wachusett Mountain State Reservation and the Mount Greylock State Reservation, Blue Hills Reservation, and the Middlesex Fells Reservation and of all land owned by the commonwealth and under the care and control of the department of conservation and recreation and used for recreational or conservation purposes, except land which at the time of the establishment of the department was held by the former Metropolitan District Commission; and of all land held by the department of environmental protection for use as a solid waste disposal facility under sections 18 through 24, inclusive, of chapter 16; and of any land acquired by the low-level radioactive waste management board pursuant to paragraph (g) of section 23 of chapter 111H. ''State-owned land'' shall not include (1) buildings, structures, improvements or other things erected thereon or affixed thereto, or (2) land which at the time of its acquisition by the commonwealth was exempt from local taxation, except land under the care and control of the department of fish and game and used as a game preserve or wildlife sanctuary and which was at the time of its acquisition by the commonwealth under the care and control of the federal government.