Be it enacted by the Senate and House of Representatives in General Court assembled, and by the authority of the same, as follows:
Section 10B of chapter 554 of the acts of 1971, inserted by section 2 of chapter 1097 of the acts of 1973, is hereby amended by striking out, in lines 4 to 6, inclusive, the words ", said payment to be an amount arrived at by applying the tax rate of the city to the assessed valuation of the facility or system".