ILLEGIBLE] EXHIBIT 10.31 FIRM GAS SERVICE EXTENSION AGREEMENT (RATE 120) THIS AGREEMENT, made and entered into this 7th day of JUNE, 2006, by and between MONTANA-DAKOTA UTILITIES CO. a Division of MDU Resources Group, Inc., a Delaware Corporation, 400...Firm Gas Service Extension Agreement • July 20th, 2006 • Red Trail Energy, LLC • Oil & gas field services, nec
