Section 30.692 - Assessment of Existing Tank System's Integrity(1) For each existing tank system that does not have secondary containment meeting the requirements of 310 CMR 30.694, the owner or operator shall determine that the tank system is not leaking and does not pose a threat of release of hazardous waste to the environment. By no later than June 1, 1989, the owner or operator shall obtain a written assessment that has been reviewed and certified by a Massachusetts registered professional engineer, in accordance with 310 CMR 30.009, and that attests to the system's integrity. Once obtained, this assessment shall be kept on file at the facility until the facility has been closed pursuant to 310 CMR 30.699.(2) This assessment shall correctly determine that the tank system is adequately designed and has sufficient structural strength and compatibility with the waste(s) to be stored or treated, to ensure that it will not collapse, rupture, or fail. In addition, the assessment shall correctly demonstrate that a minimum shell thickness has been maintained at all times to ensure sufficient shell strength. At a minimum, this assessment shall consider the following:(a) Design standard(s), if available, according to which the tank and ancillary equipment were constructed;(b) The design of the tank, including, without limitation, the foundation, structural support, seams, and pressure controls;(c) Hazardous characteristics of the waste(s) that have been or are intended to be, handled;(d) Existing corrosion protection measures;(e) Documented age of the tank system, if available (otherwise, an estimate of the age);(f) A soil corrosion survey as described in 310 CMR 30.693(1)(c);(g) The width, height, and materials of construction of the tank, and the specific gravity of the waste that has been, and is intended to be, placed in the tank, in establishing minimum shell thickness; and(h) Results of a leak test, internal inspection, or other tank integrity examination such that 1. For non-enterable underground tanks, the assessment shall include a leak test method that has been approved by the State Fire Marshal and that is capable of taking into account the effects of temperature variations, tank end deflection, vapor pockets, and high water table effects. Such a leak test must have an accuracy equal to or greater than 0.1 gallons per hour for detecting leakage from the tank with a probability of detection of 0.99 and a probability of false positive of 0.01. As the state of the art of the technology for testing underground tanks improves, the Department may specify that a test with an accuracy of better than 0.1 gallons per hour be used; and2. For other than non-enterable underground tanks and for ancillary equipment, this assessment shall include a leak test in compliance with 310 CMR 30.692(2)(h)1., or other integrity examination, that is certified by a Massachusetts registered professional engineer in accordance with 310 CMR 30.009, that addresses leaks, cracks, corrosion, and erosion. (Note: The practices described in the American Petroleum Institute (API) Publication, Guide for Inspection of Refinery Equipment, Chapter XIII, Atmospheric and Low-Pressure Storage Tanks, 4th edition, 1981, may be used, where applicable, as guidelines for conducting other than a leak test.)(3) Owners or operators of tank systems in which are stored or treated materials that are classified as hazardous waste, pursuant to amendments to 310 CMR 30.000, that take effect on or after June 1, 1989, shall conduct and complete this assessment within 12 months after the date on which the materials became a hazardous waste.(4) If, as a result of the assessment conducted in accordance with 310 CMR 30.692(2)(h), a tank system is found to be leaking or to pose a threat of release to the environment, the owner or operator must comply with the requirements of 310 CMR 30.697.(5) Until such time as secondary containment in compliance with 310 CMR 30.694 is provided, all existing tank systems shall comply with the following:(a) For non-enterable underground tanks, a leak test that meets the requirements of 310 CMR 30.692(2)(h)1. must be conducted at least once every 12 months;(b) For other than non-enterable tanks, an integrity assessment in compliance with 310 CMR 30.692(2)(h)1. or 2. must be conducted at least once every 12 months;(c) For all existing tanks: 1. The owner or operator shall maintain accurate daily inventory records and shall check such records for indication of possible leakage from each tank. Inventory shall be based on the actual daily measurement and recording of tank liquid levels and the daily recording of a material balance for wastes entering and exiting the tank. Measurements shall be taken on all days except days (e.g., Sundays, holidays) when facility business is not transacted. The inventory records shall include a daily computation of gain or loss. All records shall be made part of the operating record of the facility and shall be kept at the facility, readily available to the personnel of the Department for inspection until the facility has been closed pursuant to 310 CMR 30.699.2. With the license application, the owner or operator shall submit a proposed test for determining whether any gain or loss of material in the tank system shall be considered a statistically significant gain or loss for any one (daily) material balance or series of material balances (e.g., the running balance for a weekly period). Upon approval by the Department, this test for statistical significance shall be made a condition of the license;3. If the inventory control program required by 310 CMR 30.692(5)(c)1. indicates a statistically significant gain or loss of material as determined in compliance with 310 CMR 30.692(5)(c)2., the owner or operator shall comply with 310 CMR 30.697.4. If the Department determines in writing that it is infeasible for the owner or operator to comply with the inventory control program specified in 310 CMR 30.692(5)(c), the Department may specify in writing an alternate leak detection program.Amended by Mass Register Issue 1278, eff. 1/16/2015.