Section 38Z. (a) There shall be established a dairy farm tax credit program under which a business corporation that holds a certificate of registration as a dairy farm pursuant to section 16A of chapter 94 may be allowed a refundable income tax credit based on the amount of milk produced and sold. The credit may be claimed against the taxes due pursuant to this chapter. The credit shall be established to offset the cyclical downturns in milk prices paid to dairy farmers and shall be based on the United States Federal Milk Marketing Order for the applicable market such that if the United States Federal Milk Marketing Order price drops below a trigger price anytime during the taxable year such business corporation may receive the tax credit.

(b) The commissioner of agricultural resources, in consultation with the commissioner of revenue, shall adopt regulations for the implementation, administration and enforcement of this section, including the establishment of the trigger price, which shall take into account the operating costs of milk production including hired labor and some portion of the value of unpaid labor, and the amount of the tax credit which shall be based upon volume of milk production. The regulations shall provide that when the board of food and agriculture, established pursuant to section 1 of chapter 20, determines that an error has been made in calculating the trigger price or in reporting or collecting data used in the calculation of the trigger price or the tax credit, the commissioner shall recalculate, with or without amendments, the trigger price or tax credit.

(c) The total cumulative value of the tax credits authorized pursuant to this section and subsection (o) of section 6 of chapter 62 shall not exceed $6,000,000 annually.

(d) If the amount of the credit allowed under this section exceeds the taxpayer's liability, the commissioner of revenue shall treat such excess as an overpayment and shall pay the taxpayer 100 per cent of the amount of such excess, without interest. The commissioner of agricultural resources shall certify to the department of revenue whether a dairy farm claiming credits under this section has met the eligibility requirements provided in this section and the amount of credit to which any such eligible applicant is entitled.