This chapter identifies those solid wastes which are subject to regulation as RHS under this subtitle. Regulation .02 of this chapter defines RHS. Regulation .03 of this chapter discusses classification of RHS. Regulation .04 of this chapter establishes predisposal requirements for classes of RHS. “Radioactive hazardous substance (RHS)” means a solid waste that contains or is contaminated with radioactive material emitting primarily gamma or beta radiation and is not transuranic waste or high-level nuclear waste. “RHS” does not include: RHS owned or generated by the U.S. Department of Energy; RHS owned or generated by the U.S. Navy as a result of the decommissioning of vessels of the U.S. Navy; RHS owned or generated by the federal government as a result of any research, development, testing, or production of any atomic weapon; Any other RHS with concentrations of radionuclides that exceed the limits established by the U.S. Nuclear Regulatory Commission for class C radioactive waste, as defined by 10 CFR §61.55, in effect on January 26, 1983; Waste that, when surveyed at the container surface or, if deemed appropriate by the Secretary, sampled and analyzed, demonstrates the absence of radioactivity that can be distinguished from the background radiation level using radiation detection methods considered appropriate by the Secretary; or Excreta from individuals undergoing medical diagnosis or therapy with radioactive material. An RHS is classified according to the concentration of long-lived radionuclides and their shorter-lived precursors. The class of an RHS is determined using Table 1 in §C of this regulation or Table 2 in §D of this regulation, as applicable. Classification Determined by Long-Lived Radionuclides. If the RHS contains only radionuclides listed in Table 1, classification is determined as follows: If the concentration does not exceed 0.1 times the value in Table 1, the RHS is Class A; If the concentration exceeds 0.1 times the value in Table 1, and does not exceed the value in Table 1, the RHS is Class C; If the concentration exceeds the value in Table 1, the RHS is greater than Class C and is not generally acceptable for near-surface disposal. For RHS containing mixtures of radionuclides listed in Table 1, the total concentration is determined by the sum of fractions rule described in §G of this regulation. Table 1. Classification Determined by Short-Lived Radionuclides. If the RHS does not contain any of the radionuclides listed in Table 1, classification is determined based on the concentrations shown in Table 2, as follows: If the concentration does not exceed the value in Column 1, the RHS is Class A; If the concentration exceeds the value in Column 1, but does not exceed the value in Column 2, the RHS is Class B; If the concentration exceeds the value in Column 2, but does not exceed the value in Column 3, the RHS is Class C; If the concentration exceeds the value in Column 3, the RHS is greater than Class C and is not generally acceptable for near-surface disposal. For RHS containing mixtures of the radionuclides listed in Table 2, the total concentration is determined by the sum of fractions rule described in §G of this regulation. Classification Determined by Both Long and Short-Lived Radionuclides. If the RHS contains a mixture of radionuclides, some of which are listed in Table 1, and some of which are listed in Table 2, classification is determined as follows: If the concentration of a radionuclide listed in Table 1 does not exceed 0.1 times the value listed in Table 1, the class is that determined by the concentration of radionuclides listed in Table 2; If the concentration of a radionuclide listed in Table 1 exceeds 0.1 times the value listed in Table 1, and does not exceed the value in Table 1, the RHS shall be Class C, if the concentration of radionuclides listed in Table 2 does not exceed the value shown in Column 3 of Table 2. Classification of RHS with Radionuclides Other Than Those Listed in Table 1 and 2. If the RHS does not contain any radionuclides listed in either Table 1 or 2, it is Class A. The Sum of the Fractions Rule for Mixtures of Radionuclides. For determining classification of RHS that contains a mixture of radionuclides, a person shall determine the sum of fractions by dividing each radionuclide's concentration by the appropriate limit and adding the resulting values. A person shall take the appropriate limits from the same column of the same table. If the sum of the fractions for the column is less than 1.0, the waste class shall be determined by that column. Determination of Concentrations in RHS. The concentration of a radionuclide may be determined by indirect methods such as use of scaling factors which relate the inferred concentration of one radionuclide to another that is measured, or radionuclide material accountability, if the Secretary finds there is reasonable assurance that the indirect methods can be correlated with actual measurements. The concentration of a radionuclide may be averaged over the volume of the RHS or weight of the RHS if the units are expressed as nanocuries per gram. Before shipping RHS for disposal, a person: Shall package RHS in conformance with the conditions of the RHS facility permit issued to the site owner or operator to which the RHS will be shipped; May not package RHS for disposal in cardboard or fiberboard boxes; Shall package RHS that is in a liquid state in sufficient absorbent material to absorb twice the volume of any liquid that is present; Shall package solid RHS containing liquid to contain as little free-standing and noncorrosive liquid as is reasonably achievable, but the liquid may not exceed 1 percent of the volume; Shall insure that RHS is not readily capable of detonation, of explosive decomposition or reaction at normal pressures and temperatures, or of explosive reaction with water; Shall assure that the RHS does not contain, and is not capable of generating, concentrations of toxic gases, vapors, or fumes harmful to persons transporting, handling, or disposing of the waste, except that this does not apply to gaseous RHS packaged in accordance with §A(8) of this regulation; Shall treat, prepare, and package RHS that contains pyrophoric materials in a manner which assures that the flash point is above 100°F or 37.8°C; Shall package RHS that is in a gaseous state at an absolute pressure that does not exceed 1.5 atmospheres at 20°C; May not permit the total radioactivity to exceed 100 curies per container for RHS packages described in §A(8) of this regulation; and Shall manage RHS waste containing other hazardous waste or special medical waste, in accordance with the requirements of COMAR 26.13, to reduce, to the maximum extent practicable, the potential nonradiological hazard. Before shipping RHS classes B or C for disposal at an RHS disposal facility, a person shall: Insure that the RHS is structurally stable as indicated in §D of this regulation; Comply with the following requirements for liquid RHS or RHS containing liquids, notwithstanding the provisions of §A(3) and (4) of this regulation: Assure that liquid RHS or RHS containing liquids has been converted into a form that contains as little free-standing and noncorrosive liquid as is reasonably achievable, and Assure that the amount of liquid in the RHS does not exceed 1 percent of the volume of the RHS when the RHS is in a disposal container designed to ensure stability, or 0.5 percent of the volume of the RHS for RHS processed to a stable form; Reduce void spaces within the RHS and between the RHS and its package, to the extent practicable. A person shall clearly label each package of RHS to identify it as Class A, Class B, or Class C RHS, in accordance with Regulation .03 of this chapter. Structural stability shall be provided by the physical and chemical form used, processing the RHS to a stable form, or placing the RHS in a disposal container or structure that provides stability after disposal. Environment Article, Title 7, Subtitle 2, Annotated Code of Maryland Effective date: September 27, 1993 (20:19 Md. R. 1473)