ON JULY 22, 1999, EPA PROPOSED THE JACOB'S SMELTER SITE FOR LISTING ON THE NATIONAL PRIORITIES LIST (NPL). THE SITE CONTAINS 3 OPERABLE UNITS. OPERABLE UNIT 1 (OU1), WHICH IS THE SUBJECT OF THIS AGREEMENT, INCLUDES THE RESIDENTIAL, COMMERCIAL, AND HIGH PUBLIC USE AREAS LOCATED WITHIN THE STOCKTON TOWN LIMITS.