40 CFR § 791.40 - Basis for the proposed order.
(a) The hearing officer shall propose a fair and equitable amount of reimbursement. The formula in paragraph (b) of this section shall be presumed to be fair and equitable as applied to all persons subject to a test rule. However, the hearing officer has the discretion to modify the formula, or to use some other basis for allocation if necessary. Additional factors that may be taken into account include, but are not limited to, relative amounts of exposure attributable to each person and the effect of the reimbursement share on competitive position.
(b) In general, each person's share of the test cost shall be in proportion to its share of the total production volume of the test chemical:
(c) The burden of proposing modifications to the formula shall lie with the party requesting the modification.