36 C.F.R. § 1150.80
An affidavit is not inadmissible as such. Unless the judge fixes other time periods, affidavits shall be filed and served on the parties not later than fifteen (15) days prior to the hearing. Not less than seven (7) days prior to hearing, a party may file and serve written objections to any affidavit on the ground that he/she believes it necessary to test the truth of its assertions at hearing. In such event the assertions objected to will not be received in evidence unless the affiant is made available for cross-examination, or the judge determines that cross-examination is not necessary for the full and true disclosure of facts referred to in such assertions. Not withstanding any objection, however, affidavits may be considered in the case of any respondent who waives a hearing.
36 C.F.R. § 1150.80