The assessment by the Commission or Department of Public Service of any tax or penalty under the provisions of sections 20-25 of this title may be appealed to the Washington Superior Court. The appeal shall be filed within 90 days after the receipt by the company or its agent of written notice by the Commission or Department of its assessment. Thereupon, appropriate proceedings shall be had and the relief, if any, to which the company may be found entitled may be granted and any taxes, interest, or penalties paid, found by the Court to be illegally assessed, shall be ordered refunded to the company with interest at six percent per annum from the time of payment, with costs, and judgment entered accordingly. (Amended 1959, No. 329 (Adj. Sess.), § 39(b), eff. March 1, 1961; 1979, No. 204 (Adj. Sess.), § 13, eff. Feb. 1, 1981; 1997, No. 161 (Adj. Sess.), § 20, eff. Jan. 1, 1998.)