One chapter in the long saga of the Toms River pollution case came to a close recently when companies accused of polluting the water in the New Jersey town agreed to compensate children who were stricken with cancer and siblings who suffered emotional distress. The details of the financial arrangement, which were released yesterday, show that Ciba Specialty Chemicals, Union Carbide, and the United Water Resources (the local water utility) will pay 69 families a total of at least $13.27 million. While those families settled out of court through a mediation process, another 600 plaintiffs filed suit against the companies and are seeking class-action status and compensation for damages stemming from exposure to Toms River air and water.