Code of Maryland Regulations › Title 26 - DEPARTMENT OF ENVIRONMENT › Part 1 - SUBTITLES 01-07 › Subtitle 04 - REGULATION OF WATER SUPPLY, SEWAGE DISPOSAL, AND SOLID WASTE › Chapter 26.04.01 - Quality of Drinking Water in Maryland › Section 26.04.01.05-5 - Treatment Requirements for Ground Water Supplies

Current through Register Vol. 51, No. 14, July 12, 2024
A. Applicability. All public water suppliers
				  that use ground water are subject to the requirements of 40 CFR § 141 Subpart S
				  except public water suppliers that combine all of their ground water with
				  surface water or with ground water under the direct influence of surface water
				  prior to treatment under 40 CFR § 141 Subpart H. For the purposes of this
				  regulation, "ground water system" is defined as any public water system subject
				  to 40 CFR § 141 Subpart S, including consecutive systems receiving finished
				  ground water.
B. General
				  Requirements. Ground water suppliers subject to 40 CFR § 141 Subpart S shall
				  comply with the following requirements:
(1)
				  Sanitary survey information requirements for all ground water systems in
				  accordance with Regulation .11-3D of this chapter.
(2) Microbial source water monitoring
				  requirements for ground water suppliers that do not treat all of their ground
				  water to at least 99.99 percent (4-log) treatment of viruses, using
				  inactivation, removal, or a combination of 4-log virus inactivation and removal
				  approved by the Approving Authority, before or at the first customer in
				  accordance with Regulation .11-2 of this chapter.
(3) Treatment technique requirements,
				  described in 40 CFR §
												141.403, that apply to ground water systems
				  that have fecally contaminated source waters, as determined by source water
				  monitoring conducted under 40 CFR §
												141.402, or that have
				  significant deficiencies that are identified by the Approving Authority, or
				  that are identified by EPA under the Safe Drinking Water Act section 1445. A
				  ground water supplier with fecally contaminated source water or with
				  significant deficiencies subject to the treatment technique requirements of 40
				  CFR § 141 Subpart S shall implement one or more of the following corrective
				  action options:
(a) Correct all significant
				  deficiencies;
(b) Provide an
				  alternate source of water;
(c)
				  Eliminate the source of contamination; or
(d) Provide treatment that reliably achieves
				  at least 4-log treatment of viruses, using inactivation, removal, or a
				  combination of 4-log virus inactivation and removal approved by the Approving
				  Authority, before or at the first customer.
(4) Ground water suppliers that provide at
				  least 4-log treatment of viruses, using inactivation, removal, or a combination
				  of 4-log virus inactivation and removal approved by the Approving Authority,
				  before or at the first customer are required to conduct compliance monitoring
				  to demonstrate treatment effectiveness, as described in Regulation .11D of this
				  chapter.
(5) If requested by the
				  Approving Authority, ground water suppliers shall provide the Approving
				  Authority with any existing information that will enable the Approving
				  Authority to perform a hydrogeologic sensitivity assessment. For the purpose of
				  this regulation, "hydrogeologic sensitivity assessment" means a determination
				  of whether groundwater suppliers obtain water from hydrogeologically sensitive
				  settings.