New York Codes, Rules and Regulations › Title 10 - DEPARTMENT OF HEALTH › Chapter I - State Sanitary Code › Part 5 - Drinking Water Supplies › Subpart 5-1 - Public Water Systems › Variances and Exemptions › Section 5-1.91 - Variance from required use of any specified treatment technique

Current through Register Vol. 46, No. 28, July 10, 2024
(a) The supplier of
					 water may request, and the department may grant, one or more variances from any
					 treatment technique requirement, except filtration and disinfection, in
					 accordance with section
					 5-1.30(b),
					 (c) and (g)  of this Subpart on a finding that
					 such treatment technique is not necessary to protect the health of persons
					 served by the public water system because of the raw water source or sources of
					 such system.
(b) As a condition to
					 the granting of a variance under subdivision (a) of this section, the supplier
					 of water shall perform monitoring and other requirements as prescribed by the
					 department.
(c) Notwithstanding
					 subdivisions (a) and (b) of this section, section
					 5-1.30 
					 of this Subpart shall govern the conditions under, and the manner which, a
					 waiver of mandatory disinfection treatment for a ground source of water supply
					 may be granted.
(d) The
					 technologies listed in this section are the best technology, treatment
					 techniques, or other means available for achieving compliance with the maximum
					 contaminant levels for organic chemicals listed in section
					 5-1.52  table 3
					 of this Subpart:
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1Packed Tower Aeration
						2Granular Activated Carbon
3Oxidation (Chlorination or
						Ozonation) and Advanced Oxidation Process (AOP)
4For surface water systems or
						ground water systems influenced by surface water, GAC10, as defined in section
						5-1.1  of
						this Subpart, is the BAT for compliance with the TTHM and HAA5 MCL as a Running
						Annual Average (RAA). The other BAT for RAA compliance is enhanced coagulation
						for TTHM and HAA5 precursor removal, as described in section
						5-1.60 
						of this Subpart. For compliance with the MCLs for TTHM and HAA5 as LRAAs, the
						following are the BATs: enhanced coagulation or enhanced softening, plus GAC10;
						GAC20, as defined in section
						5-1.1  of
						this Subpart; or nanofiltration with a molecular weight cutoff less than or
						equal to 100 Daltons. Refer to section
						5-1.65 
						of this Subpart for BATs for TTHM, HAA5, Bromate, and
						Chlorite.
(e) The following
					 are the best technologies, treatment techniques, or other means available for
					 achieving compliance with the maximum contaminant levels for the inorganic
					 chemicals and radionuclides in section
					 5-1.52, tables
					 1 and 7 of this Subpart:
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(f) The following are the affordable
					 technologies, treatment techniques, or other means available to systems serving
					 10,000 persons or fewer for achieving compliance with the MCL for arsenic as
					 listed in section
					 5-1.52  table 1
					 of this Subpart:
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(g) The community water systems and
					 nontransient noncommunity water systems must install and/or use any treatment
					 method identified in subdivisions (d) and (e) of this section as a condition
					 for granting a variance except as provided in subdivision (h) of this section.
					 If after the system's installation of the treatment method, the system cannot
					 meet the MCL, that system shall be eligible for a variance.
(h) If a system can demonstrate through
					 comprehensive engineering assessments, which may include pilot plant studies,
					 that the treatment methods identified in subdivisions (d) and (e) of this
					 section would only achieve a
de minimis
reduction in
					 contaminants, the State may issue a schedule of compliance that requires the
					 system being granted the variance to examine other treatment methods as a
					 condition of obtaining the variance.
(i) If the State determines that a treatment
					 method identified in subdivision (g) of this section is technically feasible,
					 the State may require the system to install and/or use that treatment method in
					 connection with a compliance schedule. The State's determination shall be based
					 upon studies by the system and other relevant information.