1. (a) A liner is not required to be installed directly under a storage container having a capacity of one hundred thousand (100,000) gallons or more that has been constructed onsite and put into use before July 6, 1991, if one (1) of the following alternative procedures are complied with, certified to in writing by an official of the company that owns the container, and the certificate is filed with the state chemist:

   1. (1) Alternative 1 must meet the following requirements:

      1. (A) A second bottom made of steel must be constructed for the storage container and placed over the original bottom and a layer of smooth, fine gravel or coarse sand having a minimum thickness of six (6) inches.
      2. (B) The original bottom of the storage container must be tested for leaks before the sand layer or second bottom is installed. A record of the test must be kept on file at the storage facility.
      3. (C) The newly constructed bottom must be tested for leaks before any fluid fertilizer is stored on the newly constructed bottom. A record of the test must be kept on file at the storage facility or at the nearest local office from which the storage facility is administered.
      4. (D) There must be a method by which leaks from the newly constructed bottom into the sand layer may readily be detected.
      5. (E) The newly constructed bottom must be tested at least once every five (5) years for leaks. A record of the tests must be kept at the storage facility.

   2. (2) Alternative 2 must meet the following requirements:

      1. (A) The container must be emptied, cleaned, and tested for leaks. The walls and floor of the container must be tested to assure that welds and thickness of steel plates are sound and adequate to contain the fertilizers. A record of the inspection, test results, and any repairs made must be submitted to the state chemist and maintained by the owner or operator.
      2. (B) The interior floor and at least twelve (12) inches of the wall areas of the container above the floor must be coated with a liner approved by the state chemist to inhibit corrosion. A record of this procedure must be submitted to the state chemist and maintained by the owner or operator.
      3. (C) A test for leaks, approved by the state chemist, must be conducted every five (5) years thereafter. A record of the test findings and indicated repairs and maintenance must be maintained by the owner or operator.

   3. (3) Alternative 3 must meet the following requirements:

      1. (A) Monitoring devices must be installed in angled borings in the unsaturated earth materials under each tank. These monitoring devices must constitute a leak detection system for each tank in advance of the point at which any leak would reach ground water.
      2. (B) The number, length, and depth of each boring must be determined on the basis of site characteristics. The array of monitoring devices under each tank must constitute the best practical early warning detection system for tank leakage.
      3. (C) Each monitoring plan under this alternative must be implemented only upon review and approval of the state chemist.
2. (b) The secondary containment requirements under this chapter do not apply to rail cars that are periodically moved to and from the storage facility.
3. (c) The state chemist may recognize other methods that provide equivalent protection to the requirements under this chapter.

As added by P.L.98-2026, SEC.50.