In the event that there is insufficient documentation in the Request Package for the Secretary to make the applicable determinations under this part, the Secretary will notify the requester, or his or her representative. The requester will be given 60 calendar days from the date of the Secretary's notification to submit the required documentation. If the requester is unable to provide the additional documentation, he or she may write to the Secretary and explain the reason that the requested documentation is unavailable and the efforts the requester has taken to obtain the documents. The Secretary may accept such a letter in place of the required documentation or disapprove the request due to insufficient documentation. If no documentation is submitted in response to the Secretary's letter, the Secretary may disapprove the request. The Secretary also may require an authorization from the requester (or his or her representative) to try to obtain required documentation on his or her behalf.