1. (a) Complete exclusions. In addition to the tanks exempted from regulation under §334.3 of this title (relating to Statutory Exemptions), the following underground storage tanks are completely excluded from regulation under this chapter by commission directive:

   1. (1) any underground storage tank system containing a hazardous listed waste or identified under the federal Solid Waste Disposal Act, Subtitle C, (42 United States Code §6921, et seq.), or containing a mixture of such hazardous waste and other regulated substances, where such system is already subject to regulation under the federal Solid Waste Disposal Act, Subtitle C;

   2. (2) any wastewater treatment tank (including an oil-water separator and any pretreatment facility), which is an integral part of a wastewater treatment facility which is either:

      1. (A) permitted under the federal Clean Water Act, either §402 or §307(b), (33 United States Code §1251, et seq.); or
      2. (B) permitted pursuant to the Texas Water Code, Chapter 26;
   3. (3) sumps which have a capacity of less than 110 gallons;
   4. (4) emergency spill protection or emergency overflow containment tanks, including certain sumps and secondary containment systems, which are used solely for the temporary storage or containment of regulated substances resulting from a leak, spill, overfill, or other unplanned release, and where the regulated substances are routinely removed within 48 hours of the discovery of the release; provided, however, that such tanks shall be inspected for a release no less than once every month;
   5. (5) underground storage tank systems which contain regulated substances at such dilute concentrations that any release would not pose any significant threat to human health and safety or the environment.

2. (b) Partial exclusions. The following underground storage tanks are subject to all provisions of this chapter, except for Subchapter C of this chapter (relating to Technical Standards), Subchapter E of this chapter (relating to Financial Responsibility), and the certification requirements of §334.8 of this title (relating to Certification):

   1. (1) any wastewater treatment tank (including oil-water separators), where such tank is not an integral part of a wastewater treatment facility which is either:

      1. (A) permitted under the federal Clean Water Act, either §402 or §307(b), (33 United States Code §1151, et seq.); or
      2. (B) permitted pursuant to the Texas Water Code, Chapter 26;
   2. (2) any underground storage tank system that contains radioactive substances, where such system is regulated by the federal Nuclear Regulatory Commission (or its successor) under the provisions of the Atomic Energy Act of 1954 (42 United States Code §2011, et seq.);
   3. (3) any underground storage tank system that contains fuel used solely to power an emergency electrical generator system at a nuclear power generation system facility regulated by the federal Nuclear Regulation Commission (or its successor) under the provisions of the Code of Federal Regulations, Title 10, Part 50, Appendix A.
3. (c) Other exclusion. In addition to the partial exemption for hydraulic lifts covered under §334.3(b) of this title (relating to Statutory Exemptions), all other in-ground hydraulic lifts that use a compressed air/hydraulic fluid system and which hold 100 gallons or more of hydraulic oil are similarly excluded from regulation under this chapter, except that such lifts shall remain subject to the release reporting and corrective action requirements under Subchapter D of this chapter (relating to Release Reporting and Corrective Action).

Source Note:The provisions of this §334.4 adopted to be effective September 29, 1989, 14 TexReg 4714.