Section 46A. In addition to any other power the department may have to make leases, the department may lease at one time or from time to time for terms not to exceed ninety-nine years, upon such terms and conditions as the department in its discretion deems advisable, land owned by the department and no longer required for the maintenance, repair, reconstruction, improvement, use, administration or operation of the turnpike or the Boston extension of the metropolitan highway system; provided, however, that any such lease for a period of forty years or more shall be subject to the approval of the governor. A lease granted under this section may, with the consent of the department, be assigned, pledged or mortgaged and the lien of such pledge or mortgage may be foreclosed by appropriate action.

The construction or occupancy of any building or other thing erected or affixed under any lease of land under this section shall be subject to the building, fire and zoning laws, ordinances or by-laws applicable in the city or town wherein such building or other thing is located.

A copy of all leases granted by the department under the provisions of this section shall be filed by the department with the governor and with the mayor or chairman of the board of selectmen of the respective city or town and such leases shall be deemed to be public records within the meaning of chapter sixty-six.

Neither such land nor any buildings or other things erected or affixed pursuant to any such lease nor the proceeds from any such lease shall be taxed or assessed to the department under any general or special law; provided, however, that such land and buildings and other things erected or affixed pursuant to any such lease shall be taxed to the lessee thereof or his assigns in the same manner and to the same extent as if such lessee or his assigns were the owners of the land in fee; provided, further, that payment of any such taxes shall not be enforced by a lien upon or sale or taking of such land except that the leasehold estate may be sold or taken by the collector of taxes of the city or town wherein such land is situated for the nonpayment of any tax assessed as aforesaid in the manner provided by law for the sale or taking of real estate for nonpayment of local taxes. Such collector shall have for the collection of taxes assessed under this section all other remedies provided by the General Laws for the collection of taxes by collectors of cities and towns.

The department shall include in any lease of such land a provision whereby the lessee agrees, in the event that the foregoing tax provision is determined by any court of competent jurisdiction to be inapplicable, to pay annually to the city or town in which such leased land is located a sum of money in lieu of taxes which would otherwise be assessed for such year.