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<regulation prefix="Regulation" num=".14" citation="COMAR 26.13.05.14" title_num="26" subtitle_num="13" chapter_num="05" heading="Landfills.">
  <paragraph num="A.">
    <text>Applicability. This regulation applies to owners and operators of facilities that dispose of hazardous waste in landfills, except as Regulation .01 of this chapter provides otherwise.</text>
  </paragraph>
  <paragraph num="B.">
    <text>Design and Operating Requirements.</text>
    <paragraph num="(1)">
      <text>Any landfill not covered by §B(3) of this regulation or COMAR 26.13.06.22C shall have a liner system for all portions of the landfill, except for existing portions of the landfill. The liner system shall:</text>
      <paragraph num="(a)">
        <text>Have a liner that is designed, constructed, and installed to prevent any migration of wastes out of the landfill to the adjacent subsurface soil or ground water or surface water at any time during the active life, including the closure period, of the landfill. The liner shall be constructed of materials that prevent wastes from passing into the liner during the active life of the facility. The liner shall be:</text>
        <paragraph num="(i)">
          <text>Constructed of materials that have appropriate chemical properties and sufficient strength and thickness to prevent failure due to pressure gradients, including static head external hydrogeologic forces, physical contact with the waste or leachate to which they are exposed, climatic conditions, the stress of installation, and the stress of daily operation;</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>Placed upon a foundation or base capable of providing support to the liner and resistance to pressure gradients above and below the liner to prevent failure of the liner due to settlement, compression, or uplift;</text>
        </paragraph>
        <paragraph num="(iii)">
          <text>Installed to cover all surrounding earth likely to be in contact with the waste or leachate; and</text>
        </paragraph>
        <paragraph num="(iv)">
          <text>Located entirely above natural seasonal high water table. Minimal distance will be specified by the Secretary in the permit.</text>
        </paragraph>
      </paragraph>
      <paragraph num="(b)">
        <text>Have a leachate collection and removal system immediately above the liner that is designed, constructed, maintained, and operated to collect and remove leachate from the landfill. The Secretary will specify design and operating conditions in the permit to ensure that the leachate depth over the liner does not exceed 30 cm (1 foot). The leachate collection and removal system shall be:</text>
        <paragraph num="(i)">
          <text>Constructed of materials that are chemically resistant to the waste managed in the landfill and the leachate expected to be generated, and of sufficient strength and thickness to prevent collapse under the pressures exerted by overlying wastes, waste cover materials, and by any equipment used at the landfill; and</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>Designed and operated to function without clogging through the scheduled closure of the landfill.</text>
        </paragraph>
      </paragraph>
      <paragraph num="(c)">
        <text>Be located in a geohydrologic setting which is compatible with hazardous waste land disposal as determined by the Secretary. Compatibility criteria shall include but not be limited to the:</text>
        <paragraph num="(i)">
          <text>Attenuative capacity of the in-situ soils;</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>Hydraulic conductivity of the in-situ soils;</text>
        </paragraph>
        <paragraph num="(iii)">
          <text>Thickness and classification of in-situ soils; and</text>
        </paragraph>
        <paragraph num="(iv)">
          <text>Water table surface or potentiometric surface of each aquifer within 50 feet of the facility boundaries.</text>
        </paragraph>
      </paragraph>
    </paragraph>
    <paragraph num="(2)">
      <text>The owner or operator will be exempted from the requirements of §B(1) of this regulation if the Secretary finds, based on a demonstration by the owner or operator, that alternative design and operating practices, together with location characteristics, will prevent the migration of any hazardous constituents (see Regulation .06-1B of this chapter) into the ground water or surface water at any future time. In deciding whether to grant an exemption, the Secretary shall consider:</text>
      <paragraph num="(a)">
        <text>The nature and quantity of the wastes;</text>
      </paragraph>
      <paragraph num="(b)">
        <text>The proposed alternate design and operation;</text>
      </paragraph>
      <paragraph num="(c)">
        <text>The hydrogeologic setting of the facility, including the attenuative capacity and thickness of the liners and soils present between the landfill and ground water or surface waters; and</text>
      </paragraph>
      <paragraph num="(d)">
        <text>All other factors which would influence the quality and mobility of the leachate produced and the potential for it to migrate to ground water or surface water.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(3)">
      <text>The owner or operator of each new landfill, each new landfill unit at an existing facility, each replacement of an existing landfill unit, and each lateral expansion of an existing landfill unit, shall install two or more liners and a leachate collection and removal system above and between the liners, subject to the following:</text>
      <paragraph num="(a)">
        <text>The liners and leachate collection systems shall protect human health and the environment;</text>
      </paragraph>
      <paragraph num="(b)">
        <text>The liner system shall include:</text>
        <paragraph num="(i)">
          <text>A top liner designed, operated, and constructed of materials to prevent the migration of any constituent into the liner during the period the facility remains in operation, including any post-closure monitoring period; and</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>A composite bottom liner, consisting of at least two components, that satisfies the requirements of §B(3)(c) and (d) of this regulation;</text>
        </paragraph>
      </paragraph>
      <paragraph num="(c)">
        <text>The upper component of a composite bottom liner shall be designed and constructed to prevent the migration of any constituent into the upper component during the active life of the landfill and the post-closure care period;</text>
      </paragraph>
      <paragraph num="(d)">
        <text>The lower component of a composite bottom liner shall be:</text>
        <paragraph num="(i)">
          <text>Designed and constructed of materials to minimize the migration of hazardous constituents if a breach in the upper component were to occur; and</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>Constructed of at least a 3-foot thick layer of recompacted clay or other natural material with a hydraulic conductivity of no more than 1 x 10-7 centimeter per second;</text>
        </paragraph>
      </paragraph>
      <paragraph num="(e)">
        <text>The liners shall meet the requirements of §B(1)(a) of this regulation; and</text>
      </paragraph>
      <paragraph num="(f)">
        <text>The leachate collection and removal system immediately above the top liner shall be designed, constructed, operated, and maintained:</text>
        <paragraph num="(i)">
          <text>To collect and remove leachate from the landfill during the active life and post-closure care period;</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>In accordance with conditions specified by the Department in the facility permit to ensure that the leachate depth over the liner does not exceed 30 centimeters (1 foot); and</text>
        </paragraph>
        <paragraph num="(iii)">
          <text>In compliance with the requirements of 40 CFR §264.301(c)(3)(iii) and (iv), and the requirements of §D of this regulation.</text>
        </paragraph>
      </paragraph>
    </paragraph>
    <paragraph num="(4)">
      <text>The Secretary may approve substitution of alterative design and operating practices for the requirements of §B(3) of this regulation if the owner or operator demonstrates to the Secretary that alternative design and operating practices, together with location characteristics, will:</text>
      <paragraph num="(a)">
        <text>Prevent the migration of any hazardous constituent into the ground water or surface water at least as effectively as the liners and leachate collection and removal systems specified in §§B(3) and D of this regulation; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Allow detection of leaks of hazardous constituents through the top liner at least as effectively as the leak detection system required by §D(2) of this regulation.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(5)">
      <text>The double liner requirement set forth in §B(3) of this regulation may be waived by the Secretary for any monofill, if:</text>
      <paragraph num="(a)">
        <text>The monofill contains only hazardous wastes from foundry furnace emission controls or metal casting molding sand, and these wastes do not contain constituents which would render the wastes hazardous for reasons other than exhibiting the toxicity characteristic in COMAR 26.13.02.14 for one or more of EPA hazardous waste numbers D004—D017; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>One of the following applies:</text>
        <paragraph num="(i)">
          <text>The monofill has at least one liner for which there is no evidence that the liner is leaking, the monofill is located more than 1/4 mile from an underground source of drinking water, as defined in 40 CFR §144.3, and the monofill is in compliance with generally applicable ground water monitoring requirements for facilities with permits under COMAR 26.13.07; or</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>The owner or operator demonstrates that the monofill is located, designed, and operated so as to assure that there will be no migration of any hazardous constituent into ground water or surface water at any future time.</text>
        </paragraph>
      </paragraph>
    </paragraph>
    <paragraph num="(6)">
      <text>The owner or operator shall design, construct, operate, and maintain a run-on control system capable of preventing flow onto the active portion of the landfill during peak discharge from at least a 25-year storm.</text>
    </paragraph>
    <paragraph num="(7)">
      <text>The owner or operator shall design, construct, operate, and maintain a run-off management system to collect and control at least the water volume resulting from a 24-hour, 25-year storm.</text>
    </paragraph>
    <paragraph num="(8)">
      <text>Collection and holding facilities (for example, tanks or basins) associated with run-on and run-off control systems shall be emptied or otherwise managed expeditiously after storms to maintain design capacity of the system.</text>
    </paragraph>
    <paragraph num="(9)">
      <text>If the landfill contains any particulate matter which may be subject to wind dispersal, the owner or operator shall cover or otherwise manage the landfill to control wind dispersal.</text>
    </paragraph>
    <paragraph num="(10)">
      <text>The Secretary will specify in the permit all design and operating practices that are necessary to ensure that the requirements of this section are satisfied.</text>
    </paragraph>
  </paragraph>
  <paragraph num="C.">
    <text>Monitoring and Inspection. The owner or operator shall:</text>
    <paragraph num="(1)">
      <text>Inspect, during construction or installation, liners, except in the case of existing portions of liners exempt from §B of this regulation, and cover systems such as membranes, sheets, or coatings for uniformity, damage, and imperfections, such as holes, cracks, thin spots, or foreign materials;</text>
    </paragraph>
    <paragraph num="(2)">
      <text>Inspect, immediately after construction or installation:</text>
      <paragraph num="(a)">
        <text>Synthetic liners and covers to ensure tight seams and joints and the absence of tears, punctures, or blisters; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Soil-based and admixed liners and covers for imperfections including lenses, cracks, channels, root holes, or other structural non-uniformities that may cause an increase in the permeability of the liner or cover;</text>
      </paragraph>
    </paragraph>
    <paragraph num="(3)">
      <text>While a landfill is in operation, inspect the landfill weekly and after storms to detect evidence of any of the following:</text>
      <paragraph num="(a)">
        <text>Deterioration, malfunctions, or improper operation of run-on and run-off control systems;</text>
      </paragraph>
      <paragraph num="(b)">
        <text>The presence of liquids in leak detection systems;</text>
      </paragraph>
      <paragraph num="(c)">
        <text>Proper functioning of wind dispersal control system, when present; and</text>
      </paragraph>
      <paragraph num="(d)">
        <text>The presence of leachate in and proper functioning of leachate collection and removal systems, when present; and</text>
      </paragraph>
    </paragraph>
    <paragraph num="(4)">
      <text>For a landfill required to have a leak detection system under §B(3) or (4) of this regulation:</text>
      <paragraph num="(a)">
        <text>During the active life and closure period of the landfill, record the amount of liquids removed from each leak detection sump at least once each week; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>After the final cover is installed, record the amount of liquid removed from each leak detection system sump in accordance with the schedule specified in 40 CFR §264.303(c), substituting “Secretary” for “Regional Administrator”.</text>
      </paragraph>
    </paragraph>
  </paragraph>
  <paragraph num="D.">
    <text>Leachate Collection and Removal System and Leak Detection.</text>
    <paragraph num="(1)">
      <text>This section establishes requirements for a leachate collection and removal system required by §B(3) of this regulation.</text>
    </paragraph>
    <paragraph num="(2)">
      <text>A leachate collection and removal system identified in §D(1) of this regulation is:</text>
      <paragraph num="(a)">
        <text>Also a leak detection system; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Required to be capable of detecting, collecting, and removing leaks of hazardous constituents at the earliest practicable time through all areas of the top liner likely to be exposed to waste or leachate during the active life and post-closure care period.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(3)">
      <text>Except as provided in §B(4) of this regulation, the owner or operator shall ensure that a leak detection system is, at a minimum, designed, constructed, and operated in compliance with the requirements of 40 CFR §264.301(c)(3)(i)—(v), (4), and (5).</text>
    </paragraph>
  </paragraph>
  <paragraph num="E.">
    <text>Action Leakage Rate.</text>
    <paragraph num="(1)">
      <text>This section establishes requirements concerning the maximum design flow rate that the leak detection system required by §B(3) or (4) of this regulation can remove without the fluid level on the bottom of the liner exceeding 1 foot.</text>
    </paragraph>
    <paragraph num="(2)">
      <text>For the purposes of this section, “action leakage rate” means the maximum design flow rate described in §E(1) of this regulation.</text>
    </paragraph>
    <paragraph num="(3)">
      <text>The owner or operator shall provide the Department with information that the Department considers necessary for the specification of a valid action leakage rate that incorporates an adequate margin of safety to allow for uncertainties, as described in §E(4) of this regulation.</text>
    </paragraph>
    <paragraph num="(4)">
      <text>For a landfill subject to §B(3) of this regulation, the Department shall specify an action leakage rate that:</text>
      <paragraph num="(a)">
        <text>Includes an adequate safety margin, considering:</text>
        <paragraph num="(i)">
          <text>Uncertainties in the design, construction, operation, and location of the leak detection system;</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>The characteristics of the waste and leachate;</text>
        </paragraph>
        <paragraph num="(iii)">
          <text>The likelihood that other sources may contribute to liquids in the leak detection system, and the amounts of these liquids from other sources; and</text>
        </paragraph>
        <paragraph num="(iv)">
          <text>Proposed response actions; and</text>
        </paragraph>
      </paragraph>
      <paragraph num="(b)">
        <text>If exceeded, obligates the owner or operator to respond as provided in §F of this regulation.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(5)">
      <text>To determine if the action leakage rate has been exceeded, the owner or operator shall:</text>
      <paragraph num="(a)">
        <text>Convert the weekly or monthly flow rate from the monitoring data obtained in accordance with §C(4) of this regulation to an average daily flow rate in gallons per acre per day for each sump; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Unless the Department approves a different calculation, calculate the average daily flow rate for each sump:</text>
        <paragraph num="(i)">
          <text>Each week, during the active life and closure period; and</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>Monthly during the post-closure care period if monthly monitoring is required under 40 CFR §264.303(c).</text>
        </paragraph>
      </paragraph>
    </paragraph>
  </paragraph>
  <paragraph num="F.">
    <text>Response Action Plan.</text>
    <paragraph num="(1)">
      <text>Before managing waste in a landfill subject to §B(3) or (4) of this regulation, the owner or operator shall:</text>
      <paragraph num="(a)">
        <text>Develop a response action plan that:</text>
        <paragraph num="(i)">
          <text>Specifies the actions that will be taken if the action leakage rate has been exceeded; and</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>Meets the requirements of §F(2) of this regulation; and</text>
        </paragraph>
      </paragraph>
      <paragraph num="(b)">
        <text>Obtain the approval of the Department for the response action plan.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(2)">
      <text>The owner or operator shall ensure that the response action plan:</text>
      <paragraph num="(a)">
        <text>At a minimum, describes the actions specified in 40 CFR §264.304(b), except that, in complying with 40 CFR §264.304(b), the owner or operator shall substitute “the Department” for “the Regional Administrator”; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Incorporates the procedures in 40 CFR §264.304(c).</text>
      </paragraph>
    </paragraph>
    <paragraph num="(3)">
      <text>If the action leakage rate specified under §E of this regulation is exceeded, the owner or operator shall respond as specified in the approved response action plan.</text>
    </paragraph>
  </paragraph>
  <paragraph num="G.—H.">
    <text>(Reserved)</text>
  </paragraph>
  <paragraph num="I.">
    <text>Surveying and Record keeping. The owner or operator of a landfill shall maintain the following items in the operating record required under Regulation .05D:</text>
    <paragraph num="(1)">
      <text>On a map, the exact location and dimensions, including depth of each cell with respect to permanently surveyed benchmarks; and</text>
    </paragraph>
    <paragraph num="(2)">
      <text>The contents of each cell and the approximate location of each hazardous waste type within each cell.</text>
    </paragraph>
  </paragraph>
  <paragraph num="J.">
    <text>Closure and Post-Closure Care.</text>
    <paragraph num="(1)">
      <text>At final closure of the landfill or upon closure of any cell the owner or operator shall cover the landfill or cell with a final cover designed and constructed to:</text>
      <paragraph num="(a)">
        <text>Provide long-term minimization of migration of liquids through the closed landfill;</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Function with minimum maintenance;</text>
      </paragraph>
      <paragraph num="(c)">
        <text>Promote drainage and minimize erosion or abrasion of the cover;</text>
      </paragraph>
      <paragraph num="(d)">
        <text>Accommodate settling and subsidence so that the cover's integrity is maintained; and</text>
      </paragraph>
      <paragraph num="(e)">
        <text>Have a permeability less than or equal to the permeability of any bottom liner system or natural subsoils present.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(2)">
      <text>After final closure, the owner or operator shall comply with all post-closure requirements, contained in Regulation .07G—J of this chapter, including maintenance and monitoring throughout the post-closure care period. The owner or operator shall:</text>
      <paragraph num="(a)">
        <text>Maintain the integrity and effectiveness of the final cover, including making repairs to the cap as necessary to correct the effects of settling, subsidence, erosion, or other events;</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Continue to operate the leachate collection and removal system:</text>
        <paragraph num="(i)">
          <text>During post-closure period; or</text>
        </paragraph>
        <paragraph num="(ii)">
          <text>Until leachate is no longer detected;</text>
        </paragraph>
      </paragraph>
      <paragraph num="(c)">
        <text>Maintain and monitor the ground water monitoring system and comply with all other applicable requirements of Regulations .06—.06-7 of this chapter;</text>
      </paragraph>
      <paragraph num="(d)">
        <text>Prevent run-on and run-off from eroding or otherwise damaging the final cover;</text>
      </paragraph>
      <paragraph num="(e)">
        <text>Protect and maintain surveyed benchmarks used in complying with §I of this regulation;</text>
      </paragraph>
      <paragraph num="(f)">
        <text>Maintain and monitor the leak detection system in accordance with 40 CFR §264.301(c)(3)(iv) and §C(4) of this regulation; and</text>
      </paragraph>
      <paragraph num="(g)">
        <text>Comply with all applicable leak detection system requirements of this chapter.</text>
      </paragraph>
    </paragraph>
  </paragraph>
  <paragraph num="K.">
    <text>Reserved.</text>
  </paragraph>
  <paragraph num="L.">
    <text>Special Requirements for Ignitable or Reactive Waste.</text>
    <paragraph num="(1)">
      <text>Except as provided in §L(1)(b) of this regulation, a person may not place ignitable or reactive waste in a landfill, unless the waste is treated, rendered, or mixed before or immediately after placement in the landfill so that:</text>
      <paragraph num="(a)">
        <text>The resulting waste, mixture, or dissolution of material no longer meets the definition of ignitable or reactive waste under COMAR 26.13.02.11 or .13; and</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Regulation .02H(2) of this chapter is complied with.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(2)">
      <text>Except for prohibited wastes as described in COMAR 26.13.09.02B that remain subject to treatment standards in 40 CFR Part 268, Subpart D, a person may place a container of an ignitable waste in a landfill without meeting the requirements of §L(1) of this regulation if the waste is:</text>
      <paragraph num="(a)">
        <text>Disposed of in a manner that protects the waste from any materials or conditions that may cause the waste to ignite;</text>
      </paragraph>
      <paragraph num="(b)">
        <text>Contained within a nonleaking container;</text>
      </paragraph>
      <paragraph num="(c)">
        <text>Carefully handled and placed so as to avoid heat, sparks, rupture, or any other condition that might cause ignition of the waste;</text>
      </paragraph>
      <paragraph num="(d)">
        <text>Covered daily with soil or other noncombustible material to minimize the potential for ignition of the waste; and</text>
      </paragraph>
      <paragraph num="(e)">
        <text>Not disposed of in cells that contain or will contain other wastes that that may generate heat sufficient to cause ignition of the waste.</text>
      </paragraph>
    </paragraph>
  </paragraph>
  <paragraph num="M.">
    <text>Special Requirements for Incompatible Wastes. Incompatible wastes, or incompatible wastes and materials (see Regulation .24 of this chapter for example), may not be placed in the same landfill cell, unless Regulation .02H(2) of this chapter is complied with.</text>
  </paragraph>
  <paragraph num="N.">
    <text>Special Requirements for Liquid Waste.</text>
    <paragraph num="(1)">
      <text>Liquids in Landfills Prohibition.</text>
      <paragraph num="(a)">
        <text>A person may not place waste which contains free liquids in a landfill, including bulk waste, non-containerized waste, or waste in containers.</text>
      </paragraph>
      <paragraph num="(b)">
        <text>The prohibition of §N(1)(a) of this regulation applies regardless of whether sorbents have been added to the waste.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(2)">
      <text>To demonstrate the absence or presence of free liquids, a person shall use Method 9095, Paint Filter Liquids Test, as described in “Test Methods for Evaluating Solid Waste, Physical/Chemical Methods”, EPA Publication SW-846, which is incorporated by reference in COMAR 26.13.01.05A(4).</text>
    </paragraph>
    <paragraph num="(3)">
      <text>A person may not use a sorbent to eliminate free liquids from a waste that is to be disposed of in a landfill unless the sorbent meets the requirements of 40 CFR §264.314(d).</text>
    </paragraph>
  </paragraph>
  <paragraph num="O.">
    <text>Special Requirements for Containers. Unless the containers are very small, such as ampules, an owner or operator shall ensure that containers are:</text>
    <paragraph num="(1)">
      <text>At least 90 percent full when placed in a landfill; or</text>
    </paragraph>
    <paragraph num="(2)">
      <text>Crushed, shredded, or similarly reduced in volume to the maximum extent practicable before burial in a landfill.</text>
    </paragraph>
  </paragraph>
  <paragraph num="P.">
    <text>Special Requirements for Hazardous Wastes F020, F021, F022, F023, F026, and F027.</text>
    <paragraph num="(1)">
      <text>Hazardous Wastes F020, F021, F022, F023, F026, and F027 may not be placed in a landfill unless the owner or operator operates the landfill in accord with a management plan for these wastes that is approved by the Secretary under the standards set out in this section, and in accord with all other applicable requirements of this chapter. The factors to be considered are:</text>
      <paragraph num="(a)">
        <text>The volume, physical, and chemical characteristics of the wastes including their potential to migrate through the soil or to volatilize or escape into the atmosphere;</text>
      </paragraph>
      <paragraph num="(b)">
        <text>The attenuative properties of underlying and surrounding soils or other materials;</text>
      </paragraph>
      <paragraph num="(c)">
        <text>The mobilizing properties of other materials co-disposed with these wastes; and</text>
      </paragraph>
      <paragraph num="(d)">
        <text>The effectiveness of additional treatment, design, or monitoring requirements.</text>
      </paragraph>
    </paragraph>
    <paragraph num="(2)">
      <text>The Secretary may determine that additional design, operating, and monitoring requirements are necessary for landfills managing hazardous wastes F020, F021, F022, F023, F026, and F027 in order to reduce the possibility of migration of these wastes to ground water, surface water, or air so as to protect human health and the environment.</text>
    </paragraph>
  </paragraph>
</regulation>