(1) When a gas utility receives a complaint from a customer or an applicant for service, the utility must acknowledge receipt of the complaint and:

(a) Upon request, identify the utility's contact to the complainant;

(b) Investigate the complaint promptly as required by the particular case;

(c) Report the results of the investigation to the complainant;

(d) Take corrective action, if warranted, as soon as possible under the circumstances;

(e) If the complainant is dissatisfied with the results or decision, inform the complainant that the decision may be appealed to a supervisor at the utility; and

(f) If the complainant is dissatisfied after speaking with the utility's supervisor, the supervisor must inform the complainant of the complainant's right to file a complaint with the commission and provide the commission's address and toll-free telephone number.

(2) Applicants, customers, or their representatives may file with the commission:

(a) An informal complaint as described in WAC 480-07-910, Informal complaints; or

(b) A formal complaint against the utility as described in WAC 480-07-370, Pleadings—General.

(3) When the commission refers an informal complaint to the utility, the utility must:

(a) Investigate and report the results to the commission within two business days. The commission may grant an extension of time for responding to the complaint, if requested and warranted;

(b) Keep the commission informed of progress toward the solution and the final result; and

(c) Respond to the commission's request for additional informal complaint information within three business days of the request or at a date specified by the commission. The commission may grant an extension of time for responding to the complaint, if requested and warranted.

(4) Each gas utility must keep a record of all complaints for at least three years and, upon request, make them readily available for commission review. The record must contain:

(a) The complainant's name and address;

(b) The date and nature of the complaint;

(c) The action taken;

(d) The final result; and

(e) All official documents regarding the complaint.