(a) Notwithstanding any general or special law to the contrary, any restriction on use of, and any reversionary interest held by the commonwealth on, the parcel designated as the Walnut Lodge property in the first paragraph of chapter 544 of the acts of 1976 conveyed to Caritas Norwood Hospital, Inc., on June 20, 1978, are hereby released.

(b)  For the purposes of this section “Caritas Norwood Hospital, Inc. or its successors” shall mean Caritas Norwood Hospital Inc. or any person, group or entity that purchases all, or substantially all, of the assets of Caritas Christi Healthcare System or all, or substantially all, of the assets of Caritas Norwood Hospital, Inc. including any subsequent purchasers, whether such purchase is effected by sale, merger or otherwise.

(c)  In consideration for the releases set forth in subsection (a), Caritas Norwood Hospital, Inc., or its successors, shall maintain services for the treatment of alcoholism and related conditions at the Walnut Lodge property or, if not at the Walnut Lodge property, at the site of the Caritas Norwood Hospital, Inc. and upon any disposition of said Walnut Lodge property by Caritas Norwood Hospital, or its successors, 50 per cent of the gross proceeds from the sale, lease or other disposition of said parcel shall be paid by the seller to the commonwealth acting by and through the commissioner of capital asset management and maintenance.  For the purposes of this section, “gross proceeds” shall mean all payments paid to Caritas Norwood Hospital, Inc. or its successors, as and when paid, by a transferee who shall not use the property as a medical care facility. Under any change of use by Caritas Norwood Hospital, Inc. or any successor thereto, if said Walnut Lodge property, or any portion thereof, ceases to be used for the treatment of alcoholism and related conditions or, if not at the Walnut Lodge property, at the site of the Caritas Norwood Hospital Inc., then Caritas Norwood Hospital, Inc. or any successor thereto, shall pay to the commonwealth, acting by and through the commissioner of capital asset management and maintenance, the sum of 50 per cent of the assessed valuation of the land included in such change of use, as such assessment valuation appears on the real estate tax assessment listing maintained by the assessors of the town of Foxborough for the fiscal year in which such change of use occurs.  Nothing in this section shall restrict the transfer or conveyance of said property, or any portion thereof, for use as a medical care facility.