40 CFR § 761.216 - Unmanifested waste report.
(a) If a facility accepts for storage or disposal any PCB waste from an off-site source without an accompanying manifest, or without an accompanying shipping paper as described by § 761.211(e), and the owner or operator of the commercial storage or disposal facility cannot contact the generator of the PCB waste, then he shall notify the Regional Administrator of the EPA region in which his facility is located of the unmanifested PCB waste so that the Regional Administrator can determine whether further actions are required before the owner or operator may store or dispose of the unmanifested PCB waste, and additionally the owner or operator must prepare and submit a letter to the Regional Administrator within 15 days after receiving the waste. The unmanifested waste report must contain the following information:
(2) The date the facility received the waste;
(7) A brief explanation of why the waste was unmanifested, if known.
(ii) If the waste was sent back to the generator, why and when.