BOSTON (Standard & Poor's) Feb. 7, 2002ùStandard & Poor's today assigned its single-'A'-plus rating to the town of Northbridge, Mass.' $29.5 million GO bonds series 2002 dated Feb. 15, 2002, due Feb. 15, 2022. The bonds are scheduled to sell on Feb. 12, 2002. The outlook is stable. The rating reflects: -- Average wealth indicators, -- Consistent financial performance with increasing reserves, and -- A low debt burden. The bonds are secured by the town's full faith and credit pledge. Northbridge, population 13,964, is located nearly 40 miles west of Boston and 15 miles southeast of Worcester. The town's tax base has grown considerably since fiscal 1997, increasing 40% to $730 million in fiscal 2002. Much of the growth is