Applying the federal transaction test to a plea of claim preclusion on a CERCLA claim for contribution by a potentially responsible party, this decision holds that the later suit is not precluded because it is not on the same cause of action.  The prior action was by the then-current owner of Property 1 for contribution to the cost of remediating pollution on adjoining Property 2 (to which the pollution migrated from Property 1).  The current suit is for the cost to remediate pollution on  Property 1 itself.