Conn. Gen. Stat. § 12-124a

(b) Whenever any municipality has approved abatement of taxes as provided in subsection (a) of this section, the owner or owners shall deliver to the tax collector in such municipality, not later than ten days following the tax due date for such taxes abated, an agreement, on a form executed and acknowledged in the form and manner required for the transfer of an interest in real property, to reimburse such municipality in the amount of the taxes abated, with interest at six per cent per annum or such rate as approved by the legislative body. Such agreement shall contain a legal description of the real property with respect to which such abatement is approved and shall be recorded in the land records of such municipality. Such agreement shall constitute a lien on such real property which shall remain valid until paid. Such lien shall be due and payable in full upon the sale or transfer of such real property or upon the death of the owner, or if owned by more than one person at the time such lien is created, upon the death of the last of such owners surviving. Such lien shall be released by the tax collector in such municipality when the taxes secured thereby have been paid. Liens recorded under the provisions of this subsection shall have the same precedence as tax liens under section 12-172 .