(October 29, 2003) - (Pryor, Oklahoma-AP) -- Tyson Foods and two poultry companies may have to fight off a class-action lawsuit over water quality. Lawyers representing people who live along Oklahoma's Grand Lake are seeking class-action status for a lawsuit that could draw in thousands of plaintiffs. Tyson Foods is based in Springdale, Arkansas. Also named are Arkansas companies Simmons Foods and Peterson Farms. A judge will decide if the large group of residents has grounds to sue. Four people who own property on the northeast Oklahoma lake allege the companies' poultry operations are tainting the lake with an oily scum and excessive algae growth. They're seeking damages on allegations the pollution has depressed property values. A hearing in the case is to continue today.