Current through Register Vol. 48, No. 38, September 20, 2024
a) Scope of This Subpart S. The requirements
of this Subpart S constitute NPDWRs.
b) Applicability. This Subpart S applies to
all PWS suppliers that use groundwater, except that it does not apply to public
water systems that combine all of their groundwater with surface water or with
groundwater under the direct influence of surface water prior to treatment
under Subpart B. For the purposes of this Subpart S, "GWS" is defined as any
PWS that meets this applicability statement, including a consecutive system
receiving finished groundwater.
c)
General Requirements. A supplier subject to this Subpart S must comply with the
following requirements:
1) Sanitary survey
information requirements for all GWS suppliers, as described in Section
611.801.
2) Microbial source water monitoring
requirements for GWS suppliers that do not treat all of their groundwater to at
least 99.99 percent (4-log) treatment of viruses (using inactivation, removal,
or an Agency-approved combination of 4-log virus inactivation and removal)
before or at the first customer, as described in Section
611.802.
3) Treatment technique requirements,
described in Section
611.803,
that apply to GWS suppliers that have fecally contaminated source waters, as
determined by source water monitoring conducted under Section 611.802, or which
have significant deficiencies that are identified by the Agency, by a SEP, or
which are identified by USEPA under SDWA section 1445 (
42 USC
300j-4) . A GWS supplier with fecally
contaminated source water or with significant deficiencies subject to the
treatment technique requirements of this Subpart S must implement one or more
of the following corrective action options: correct all significant
deficiencies; provide an alternate source of water; eliminate the source of
contamination; or provide treatment that reliably achieves at least 4-log
treatment of viruses (using inactivation, removal, or an Agency-approved
combination of 4-log virus inactivation and removal) before or at the first
customer.
4) A GWS supplier that
provides at least 4-log treatment of viruses (using inactivation, removal, or
an Agency-approved combination of 4-log virus inactivation and removal) before
or at the first customer is required to conduct compliance monitoring to
demonstrate treatment effectiveness, as described in Section
611.803(b).
5) If requested by the Agency, a GWS supplier
must provide the Agency with any existing information that will enable the
Agency to perform a hydrogeologic sensitivity assessment.
BOARD NOTE: The Board moved the definition of "hydrogeologic
sensitivity assessment" to the definitions provision of this Part: Section
611.101.
d) This subsection (d)
corresponds with
40 CFR
141.400(d), which recites
past effective dates. This statement maintains structural consistency with the
corresponding federal provision.
BOARD NOTE: Derived from
40 CFR
141.400.
