(1) The advanced environmental mitigation revolving account is created in the custody of the treasurer, into which the department shall deposit directly and may expend without appropriation:
(a) An initial appropriation included in the department of transportation's 1997-99 budget, and deposits from other identified sources;
(b) All moneys received by the department from internal and external sources for the purposes of conducting advanced environmental mitigation; and
(c) Interest gained from the management of the advanced environmental mitigation revolving account.
(2) During the 2011-2013 and 2013-2015 fiscal biennia, the legislature may transfer from the advanced environmental mitigation revolving account to the motor vehicle account [fund] such amounts as reflect the excess fund balance of the advanced environmental mitigation revolving account.
(3) During the 2019-2021 fiscal biennium, the legislature may direct the state treasurer to make transfers of moneys in the advanced environmental mitigation revolving account to the motor vehicle fund.