N.C. Gen. Stat. § 105-344
If any public service company fails or refuses to pay any taxes imposed on its property by any taxing unit of this State, the taxing unit may bring an action in the appropriate division of the General Court of Justice of the county in which the taxing unit is located for the recovery of the tax. Not less than 15 days before such an action is instituted, the taxing unit shall notify the taxpayer by registered or certified mail of its intention to bring the action. The judgment rendered in such an action shall include the tax imposed and unpaid and, as an additional tax, a penalty of fifty percent (50%) of the amount of the tax with interest on the sum of these taxes at the rate of nine percent (9%) per annum from the date the tax was due to be paid, plus reasonable attorneys' fees for the prosecution of the action to be fixed by the court. (The awarding of attorneys' fees by the court shall not prevent the taxing unit from paying its attorney an additional fee pursuant to contract, nor shall it prevent the taxing unit from requiring that the attorneys' fees awarded by the court be paid into the general fund of the taxing unit in accordance with any arrangement between the taxing unit and its attorneys.) The judgment rendered by the court may include a mandamus ordering the payment of the judgment, penalty, interest, and costs including the attorneys' fees as part of the costs.
If, during the pendency of an action brought under this section, additional or subsequent taxes shall accrue, those taxes, together with penalties and interest, may be included in the judgment if, prior to rendition of the judgment, the tax collector of the taxing unit files with the court a certificate of the additional taxes, penalties, and interest.
In any action brought under this section, the appraised valuation of the taxpayer's property as determined, allocated, and certified to the taxing unit by the Department of Revenue shall be conclusive and shall not be subject to collateral attack.
N.C. Gen. Stat. § 105-344