SPARTA-Sparta residents may pass it often to watch their children play on the soccer and baseball fields at Station Park, probably never noticing or at least paying much attention to the abandoned property nearby. The site is of great interest, though, to the state Department of Environmental Protection, which is suing its deceased owner and now-defunct corporation to recoup damages for cleanup of soil and groundwater pollution. The civil lawsuit, filed in Superior Court in Newton listing parent company A.O. Corp. as the defendant, seeks damages from A.O. Polymer, which operated on Station Road from the early 1960s until 1993. "It's no hazard to the adjacent property," said Henry Underhill, Sparta Township manager. "It's all groundwater pollution. Kids play in the park all the time. There's no hazard to them." DEP has a lien on the property. Underhill said the company owes back taxes, but Sparta won't foreclose on the property until the township can be assured it won't be responsible for any remediation costs. "Maybe the lawsuit will solve that," he said. Underhill said a group of rail enthusiasts had expressed interest in preserving an old train station at the site. The lawsuit seeks unspecified damages for prior and current cleanups, lost use of groundwater and natural resource damage beyond compensation for cleanup costs. The property had been a source of concern for Sparta residents and regulatory authorities since the 1970s, when citizens first noticed odors in well water and in the air. In 1978, the Sparta Health Department and the state found volatile organic compounds in three domestic water wells. A.O. Polymer produced resins plastics, paper coatings, and specialty polymers and was involved in the reclamation of spent solvents. During operation of the facility, the state cited A.O. Corp twice for improperly discharging plant wastewater and 13 times for air quality violations. The the federal Environmental Protection Agency (EPA) said it discovered unlined disposal pits and hundreds of leaking and deteriorated drums at the site. In 1981, the DEP removed 3,000 tons of contaminated soil and 900 drums. The following year, EPA listed the property as a Superfund site, or one posing the greatest threat to the environment and human health. After completing plans in 1991, the federal agency ordered A.O. Corp and International Business Machines to clean up the property a year later. IBM, which in the 1960s-1970s sent computer chip cleaners to the site for processing, complied with the order. A.O. Corp. did not, the lawsuit states. Since then, buildings on the site were cleaned up and removed, but the groundwater remains contaminated and the soil is still on the Superfund list, DEP said. EPA said a plume of groundwater has migrated to the Wallkill River, about ¼ mile from the site. EPA estimates approximately 1,000 people live in the surrounding area, and the site threatens the Allentown aquifer, a source of potable water for 5,000 people.