Mass. Gen. Laws ch. 60 § 76B
Errors or irregularities in respect to water, sewer use or municipal light rates and charges included in a tax title account, including interest and costs, or in the proceedings relating thereto, shall not render invalid a tax title otherwise valid; but in proceedings under sections sixty-four to seventy-six A, inclusive, such errors or irregularities shall be taken into consideration in fixing the terms of redemption, whether upon petition for foreclosure or for redemption, and the court shall specifically indicate in any decree fixing the terms of redemption any amounts excluded from the account by reason of such errors or irregularities. The city or town in which the land lies shall pay to a person holding such a tax title the amounts so indicated, with interest at the rate of six per cent per annum from the date of redemption and, if the city or town fails to make such payment within three months after written demand therefor made upon the city or town treasurer, such person may recover the same in an action of contract brought against the city or town within one year after the date of redemption. The city or town treasurer shall notify the board or officer in charge of the water, sewer or municipal light department of the amount so excluded by court decree.
Mass. Gen. Laws ch. 60, § 76B