EPA began the RI/FS for the Lower Passaic River Study Area, with funding from the Settling Parties under a separate agreement (EA# 02-2004-2011) but found that it would be more costly than anticipated. The 73 Settling Parties have agreed to take over and complete the RI/FS and pay EPA's oversight costs. The Settling Parties are performing the modeling for the RI/FS but EPA may take back the modeling work if it is not satisfied without having to submit to dispute resolution.