Mass. Gen. Laws ch. 63, § 38Q
(a) A business corporation which commences and diligently pursues an environmental response action on or before August 5, 2028 and which achieves and maintains a permanent solution or remedy operation status in compliance with chapter 21E and the regulations adopted under that chapter which includes an activity and use limitation shall, at the time the permanent solution or remedy operation status is achieved, be allowed a base credit of 25 per cent of the net response and removal costs incurred between August 1, 1998 and January 1, 2029 for any property it owns or leases for business purposes and which is located within an economically distressed area as defined in section 2 of chapter 21E, if these costs are not less than 15 per cent of the assessed value of the property before remediation, and if the site was reported to the department of environmental protection. A credit of 50 per cent of these costs shall be allowed for a corporation which achieves and maintains a permanent solution or remedy operation status in compliance with chapter 21E and the Massachusetts contingency plan provided in 310 CMR 40.0000 which does not include an activity and use limitation. Only a business corporation that is an eligible person as defined by section 2 of chapter 21E, and not subject to any enforcement action brought under chapter 21E, shall be allowed a credit.
Any credit allowed under this subsection may be taken only after a response action outcome statement or remedy operation status submittal has been filed with the department of environmental protection as set forth in said Massachusetts Contingency Plan.