JACKSON, Wis. (AP) – Homeowners are suing over a massive gasoline spill in Wisconsin this summer.   Attorneys say 150 Jackson area families filed a lawsuit Monday against the pipeline owner and operator. The homeowners allege they suffered economic and emotional damage.  Attorneys say many of the homeowners have been unable to use water from their wells because they have tested positive for benzene. The homeowners are asking for compensation for their losses, including the establishment of a medical monitoring fund for early cancer screening.   Messages left for pipeline owner West Shore Pipe Line Co. of Illinois and operator Buckeye Partners L.P. of Houston were not immediately returned Monday.  A section of 10-inch pipe in the Milwaukee-to-Green Bay line ruptured July 17 in Jackson, spilling an estimated 54,600 gallons of gasoline in a few minutes.