gisb gas contract attached review gas industry standards board base contract form revised special provisions agreement formatted preprinted subject customization via special provisions generally utilized gtc provisions customize special provisions agreement used interruptible gas firm gas delivery period greater 31 days cordially mary cook enron north america corp 1400 smith 38 th floor legal houston texas 77002 7361 713 345 7732 713 646 3393 fax mary cook enron com