15 C.F.R. § 990.14
(a) Trustees.
(5) Considerations. In determining the nature and extent of participation by the responsible parties or their representatives, trustees may consider such factors as:
(6) Request for alternative assessment procedures.
(i) The participating responsible parties may request that trustees use assessment procedures other than those selected by the trustees if the responsible parties:
(ii) Trustees may reject the responsible parties' proposed assessment procedures if, in the sole judgment of the trustees, the proposed assessment procedures: