This is the fifth de minimis settlement for the Mercury Refining Site. The settlement requires 12 de minimis parties to pay their specified percentage share of past response costs and future response costs plus a 100% premium on all future response costs less an orphan share equal to 25% of the ROD remedy costs. The 12 parties to this agreement were amongst the 421 de minimis parties that were sent a de minimis offer in January 2009. For a variety of reasons, these 12 parties never received that settlement offer. Under this agreement, they are paying what they would have paid had they settled in 2009.