ATCP 93.535(2)(2) Any complete or partial tank lining conducted any time after the original tank lining was installed is considered a repair of the lining. ATCP 93.535(3)(3) The owner shall notify the authorized agent and the department in writing at least 5 business days before having the inspection performed. ATCP 93.535(3m)(3m) Before commencing any inspection, the underground tank system liner shall ensure that the tank is prepared for inspection in accordance with API 1631. ATCP 93.535(4)(4) Tank lining inspections shall use one of the following methods: ATCP 93.535(4)(a)(a) Video camera inspection in accordance with KWA Method A only. A pre-inspection tightness test shall be performed in accordance with s. ATCP 93.510 (4); if the tank fails the tightness test, video inspection is not permitted. ATCP 93.535(5)(a)(a) For tanks with lining and cathodic protection added at the same time, if cathodic protection has been maintained at a protective level: ATCP 93.535(5)(b)(b) For tanks with cathodic protection added after the tank was lined: ATCP 93.535(5)(b)1.1. For first 5-year inspection following cathodic protection addition with cathodic protection maintained at a protective level, physical inspection is required under sub. (4) (b). ATCP 93.535(5)(b)2.2. If first 5-year inspection indicates no change of external wall thickness, then subsequent 5-year inspections can be performed as allowed in sub. (4). ATCP 93.535(5)(c)(c) For lined tanks without cathodic protection installed, physical inspection is required under sub. (4) (b). ATCP 93.535(5)(d)(d) The use of the equipment to perform the inspections under par. (a) shall be in accordance with national consensus standards. ATCP 93.535(5)(e)(e) Inspection and repairs of lined tanks shall be conducted by or under the direct supervision of an underground tank system liner in accordance with s. ATCP 93.240 (1) (b). ATCP 93.535(5)(f)(f) The person performing the inspection shall be certified by the manufacturer of the inspection equipment. ATCP 93.535(7)(7) Repair of tank linings shall comply with the requirements of API 1631 and the lining manufacturer’s specifications. ATCP 93.535(7g)(7g) Tanks that have an overall average tank metal thickness or an average tank thickness of a designated thin wall area of less than 75 percent or any through-wall perforations shall be immediately closed per s. ATCP 93.560. ATCP 93.535(7r)(7r) Tanks that have an overall average tank metal thickness or an average tank thickness of a designated thin wall area of 75 percent to 85 percent shall have an impressed current system installed per s. ATCP 93.520 or be immediately closed per s. ATCP 93.560. ATCP 93.535(8)(8) A lined tank that requires repairs to more than 10 percent of the lined surface shall be returned to service only if all of the following conditions are met: ATCP 93.535(8)(b)(b) The tank has impressed current corrosion protection installed in accordance with s. ATCP 93.520 before being placed back into service. ATCP 93.535(9)(9) The person performing the inspection shall provide a report to the owner, authorized agent, and the department within 15 days of completing the inspection that describes all of the following items in addition to those required in API 1631: ATCP 93.535(9)(b)(b) The total dimension of the area in square inches that has been repaired by lining. ATCP 93.535(10)(10) Before placing any tank back into service under this section, both of the following shall occur in the following order: