(

a) A retail transactions and use tax ordinance applicable to the entirety of, or a portion of, the incorporated and unincorporated territory within the area of the board pursuant to

Section shall be imposed by the board in accordance with

Section 125485, the Transactions and Use Tax Law (Part 1.6 (commencing with

Section 7251) of Division of the Revenue and Taxation Code), and

Section of

Article XIII C of the California Constitution. The tax ordinance shall take effect at the close of the polls on the day of election at which the proposition is adopted. The initial collection of the transactions and use tax shall take place in accordance with

Section 125483. (

b) If, at any time, the voters do not approve the imposition of the transactions and use tax, this

chapter remains in full force and effect. The board may, at any time thereafter, submit the same, or a different, measure to the voters in accordance with this chapter. (

c) The portion of the area of the board to which the tax would apply shall be determined by the board before the electors vote on the measure. (

d) If the tax only applies to a portion of an area of the board, both of the following shall apply: (1) (

A) The incorporated area of each city and of contiguous cities within the area of the board shall be either wholly included within that portion or wholly excluded from that portion. For purposes of this subparagraph, “contiguous cities” means two or more cities with shared borders. (

B) The entire unincorporated area of the board shall either be wholly included within that portion or wholly excluded from that portion. (2) (

A) The board shall not enter into a construction contract over one million dollars ($1,000,000) that would be in part or wholly financed through the tax with any entity unless the entity provides to the board an enforceable commitment that the entity and its subcontractors at every tier will use a skilled and trained workforce to perform all work on the project or a contract that falls within an apprenticeship occupation in the building and construction trades in accordance with

Chapter 2.9 (commencing with

Section 2600) of Part of Division of the Public Contract Code. (

B) This paragraph shall not apply if any of the following requirements are met: (

i) The board has entered into a project labor agreement that will bind all contractors and subcontractors performing work on the project. (ii) The board has contracted to use a skilled and trained workforce and the entity has agreed to be bound by that project labor agreement. (iii) The project or contract is being performed under the extension or renewal of a project labor agreement that was entered into by the board before January 1, 2019. (iv) The entity has entered into a project labor agreement that will bind the entity and all its subcontractors at every tier performing the project or the entity has contracted to use a skilled and trained workforce. (

C) For purposes of this paragraph, “project labor agreement” has the same meaning as defined in paragraph (1) of subdivision (

b) of

Section of the Public Contract Code. (

e) The revenues derived from the tax shall be spent within, or for the benefit of, the portion of the area of the board to which the tax applies, and shall be spent only on transportation and transit infrastructure and services. (

f) Any revenues derived from the tax shall supplement, and not supplant, other transportation revenues available to the portion of the area of the board to which the tax applies.