HAMPTON, N.H. – New England public utility Unitil Corp. said Wednesday it resolved state regulatory concerns arising from its proposed purchase of two companies from Indiana-based NiSource Inc.

In February, Unitil said it would buy Northern Utilities Inc. and Granite State Gas Transmission Inc. for $160 million and roughly $25 million in natural gas storage inventory and other working capital.

Northern Utilities serves 52,000 customers in Maine and New Hampshire. Granite State runs 86 miles of pipeline in the same states and provides natural gas transmission for Northern Utilities.

Unitil worked with Maine and New Hampshire regulators to settle concerns about rates, customer service and operations of the two companies to be acquired.

Northern agreed to enhanced safety and reliability programs and to upgrade customer service quality programs in both states. Unitil will also conduct with parties in both states a study of potential changes in organization or regulation of Granite State Gas Transmission.

The two states’ consumer advocate offices agreed to recommend that their respective commissions approve Unitil’s acquisition of Northern.

“These settlements provide a fair and appropriate framework and a predictable regulatory roadmap for Unitil’s new gas distribution businesses in Maine and New Hampshire, and we look forward to timely approval, closing and transition,” Mark H. Collin, Unitil chief financial officer, said in a statement.

Final orders are expected in states no later than Oct. 1, 2008, said Unitil, whose shares rose 10 cents to $26.50 in afternoon trading.