(a) Discovery is limited to requests for admissions, requests for production of documents, interrogatories, and depositions as authorized by §16.215.

(b) The hearing officer shall limit the frequency and extent of discovery permitted by this section if a party shows that—

(1) The information requested is cumulative or repetitious;

(2) The information requested may be obtained from another less burdensome and more convenient source;

(3) The party requesting the information has had ample opportunity to obtain the information through other discovery methods permitted under this section; or

(4) The method or scope of discovery requested by the party is unduly burdensome or expensive.