(a) Availability. Any participant may serve upon any other participant a written request to supply information, such as responses to data requests and interrogatories, or copies of documents.

(b) Procedures.

(1) A request under this section must identify with specificity the information or material sought and will specify a reasonable time within which the matter sought must be furnished.

(2) Unless provided otherwise by the presiding officer, copies of any discovery request must be served upon the presiding officer and on all participants to the proceeding.

(3) Each discovery request must be answered separately and fully in writing.

(4) Responses to discovery requests are required to be served only on the participant requesting the information, Commission trial staff, and any other participant that specifically requests service. The presiding officer may direct that a copy of any responses be furnished to the presiding officer. Responses must be served within the time limit specified in the request or otherwise provided by the presiding officer.

(5) If the matter sought is not furnished, the responding participant must provide, in accordance with Rule 410, written explanation of the specific grounds for the failure to furnish it.