1. (a) All tanks proposed for use in a wastewater system described in this Subchapter shall be approved by the Department. The tank design shall be approved based on the plans and specifications submitted in accordance with Subparagraphs (c)(1) through (c)(8) of this Rule.
2. (b) The tank manufacturer shall submit three copies of the plans and specifications for the initial design of each tank to the Department for approval.

3. (c) Plans and specifications for tanks with a total liquid capacity less than or equal to 4,000 gallons shall include the following:

   1. (1) all tank dimensions in inches, including:

      1. (A) top, bottom, and sidewall thickness and variations;
      2. (B) minimum and maximum dimensions on tanks with tapered or ribbed walls;
      3. (C) baffle wall location and minimum and maximum thickness and variations;
      4. (D) location and dimension of all openings in baffle wall for gas and liquid movement; and
      5. (E) dimensions of all compartments;
   2. (2) material type and strength, including reinforcement material and location, as applicable, specified by the manufacturer;
   3. (3) method for fastening the baffle wall to the tank interior;
   4. (4) liquid depth and operating capacity in gallons;
   5. (5) pipe penetration boot locations and pipe penetration boots approved in accordance with Rule .1404 of this Section;
   6. (6) methods and material for sealing sections and forming watertight joints in tanks with multiple sections;
   7. (7) drawings showing access openings, tank lids, access manhole risers, and other proposed appurtenances to the tank;
   8. (8) tank manufacturer and PE requirements for installation, including bedding, additional sealing methods, and leak testing procedures.
4. (d) Plans and specifications for tanks with a total liquid capacity greater than 4,000 gallons and all tanks designed for traffic loads shall be designed by a PE in accordance with ASTM C890. Plans shall show the design, including all the information listed in Paragraph (c) of this Rule and engineering calculations showing the minimum and maximum soil burial depth, water table, and traffic load the tank is designed to support.
5. (e) Plans for tanks not proposed for general use and issued an identification number under this Section shall meet the minimum requirements of this Section and shall be approved by the Department.
6. (f) The Department or LHD may inspect approved tanks at the place of manufacture, the inventoried sites of the distributors, or at the installation of the tank in a wastewater system for compliance with the approved plans and specifications.
7. (g) Tanks found to be out of compliance shall be brought back into compliance by the tank manufacturer or the installer as directed by the Department or LHD. Tanks that are not or cannot be brought into compliance shall not be used in a wastewater system and the imprints identified in Rule .1402(d)(15) or (e)(8) of this Section shall be permanently marked over by the authorized agent.

History Note: Authority G.S. 130A-335(e), (f), and (f1); S.L. 2024-49, s.4.42;
Eff. January 1, 2024;
Amended Eff. June 1, 2026.