(a) Determination by judge. All parties to a proceeding shall be determined at the preliminary hearing or when the judge otherwise designates. To be admitted as a party, a person must have a justiciable interest in the matter being considered and must, unless the person is specifically named in the matter being considered, appear at the preliminary hearing in person or by representative and seek to be admitted as a party. After parties are designated, no person will be admitted as a party except upon a finding that good cause and extenuating circumstances exist and that the hearing in progress will not be unreasonably delayed.
(b) Parties.
  (1) The executive director is a mandatory party to all commission proceedings concerning matters in which the executive director bears the burden of proof, and in the following commission proceedings:
    (A) matters concerning Texas Water Code (TWC), §11.036 and §11.041; TWC, Chapters 13, 35, 36, and 49 - 66; and Texas Local Government Code, Chapters 375 and 395;
    (B) matters arising under Texas Government Code, Chapter 2260 and Chapter 11, Subchapter D of this title (relating to Resolution of Contract Claims); and
    (C) matters under TWC, Chapter 26, Subchapter I, and Chapter 334, Subchapters H and L of this title (relating to Reimbursement Program and Overpayment Prevention).
  (2) In addition to paragraph (1) of this subsection, the executive director is always a party in contested case hearings concerning permitting matters, pursuant to, and in accordance with, the provisions of §80.108 of this title (relating to Executive Director Party Status in Permit Hearings).
  (3) The public interest counsel of the commission is a party to all commission proceedings.
  (4) The applicant is a party in a hearing on its application.
  (5) Affected persons shall be parties to hearings on permit applications, based upon the standards set forth in §55.203 of this title (relating to Determination of Affected Person). Regardless of any other law, a state agency, except a river authority, may not be a party to a hearing on an application received by the commission on or after September 1, 2011 unless the state agency is the applicant.
  (6) The parties to a contested enforcement case include:
    (A) the respondent(s);
    (B) any other parties authorized by statute; and
    (C) in proceedings alleging a violation of or failure to obtain an underground injection control or Texas Pollutant Discharge Elimination System permit, or a state permit for the same discharge covered by a National Pollutant Discharge Elimination System (NPDES) permit that has been assumed by the state under NPDES authorization, any other party granted permissive intervention by the judge. In exercising discretion whether to permit intervention, the judge shall consider whether the intervention will unduly delay or prejudice the adjudication of the rights of the original parties.
  (7) The parties to a hearing upon a challenge to commission rules include the person(s) challenging the rule and any other parties authorized by statute.
  (8) The parties to a permit revocation action initiated by a person other than the executive director shall include the respondent and the petitioner.
  (9) The parties to a post-closure order contested case are limited to:
    (A) the executive director;
    (B) the applicant(s); and
    (C) the Public Interest Counsel.
(c) Alignment of participants. Participants (both party and non-party) may be aligned according to the nature of the proceeding and their relationship to it. The judge may require participants of an aligned class to select one or more persons to represent them in the proceeding. Unless otherwise ordered by the judge, each group of aligned participants shall be considered to be one party for the purposes of §80.115 of this title (relating to Rights of Parties) for all purposes except settlement.
(d) Effect of postponement. If a hearing is postponed for any reason, any person already designated as a party retains party status.

Source Note: The provisions of this §80.109 adopted to be effective June 6, 1996, 21 TexReg 4763; amended to be effective December 1, 1997, 22 TexReg 11381; amended to be effective September 23, 1999, 24 TexReg 8276; amended to be effective November 15, 2001, 26 TexReg 9105; amended to be effective January 30, 2003, 28 TexReg 6958; amended to be effective May 3, 2012, 37 TexReg 3147; amended to be effective January 3, 2019, 43 TexReg 8611; amended to be effective May 14, 2020, 45 TexReg 3087