| (I) Containment facilities for a single container or
for multiple interconnected containers must be large enough to hold
the maximum amount of chemical that can be stored with a minimum freeboard
of six vertical inches or to hold 110% of the total volume of the
container(s), whichever is less.
(II) Common containment for multiple containers that
are not interconnected must be large enough to hold the volume of
the largest container with a minimum freeboard of six vertical inches
or to hold 110% of the total volume of the container(s), whichever
is less.
(III) The materials used to construct containment structures
must be compatible with the chemicals stored in the tanks.
(IV) Incompatible chemicals shall not be stored within
the same containment structure.
(V) No containment facilities are required for hypochlorite
solution containers that have a capacity of 55 gallons or less.
(VI) On a site-specific basis, the executive director
may approve the use of double-walled tanks in lieu of separate containment
facilities.
(F) Chemical transfer pumps and control systems must
be designed to minimize the possibility of leaks and spills.
(G) Piping, pumps, and valves used for chemical storage
and transfer must be compatible with the chemical being fed.
(2) Chemical feed and metering facilities shall be
designed so that chemicals shall be applied in a manner which will
maximize reliability, facilitate maintenance, and ensure optimal finished
water quality.
(A) Each chemical feeder that is needed to comply with
a treatment technique or MCL requirement shall have a standby or reserve
unit. Common standby feeders are permissible, but generally, more
than one standby feeder must be provided due to the incompatibility
of chemicals or the state in which they are being fed (solid, liquid,
or gas).
(B) Chemical feed equipment shall be sized to provide
proper dosage under all operating conditions.
(i) Devices designed for determining the chemical feed
rate shall be provided for all chemical feeders.
(ii) The capacity of the chemical feeders shall be
such that accurate control of the dosage can be achieved at the full
range of feed rates expected to occur at the facility.
(iii) Chemical feeders shall be provided with tanks
for chemical dissolution when applicable.
(C) Chemical feeders, valves, and piping must be compatible
with the chemical being fed.
(D) Chemical feed systems shall be designed to minimize
the possibility of leaks and spills and provide protection against
backpressure and siphoning.
(E) If enclosed feed lines are used, they shall be
designed and installed so as to prevent clogging and be easily maintained.
(F) Dry chemical feeders shall be located in a separate
room that is provided with facilities for dust control.
(G) Coagulant feed systems shall be designed so that
coagulants are applied to the water prior to or within the mixing
basins or chambers so as to permit their complete mixing with the
water.
(i) Coagulant feed points shall be located downstream
of the raw water sampling tap.
(ii) Coagulants shall be applied continuously during
treatment plant operation.
(H) Chlorine feed units, ammonia feed units, and storage
facilities shall be separated by solid, sealed walls.
(I) Chemical application points shall be provided to
achieve acceptable finished water quality, adequate taste and odor
control, corrosion control, and disinfection.
(g) Other treatment processes. Innovative/alternate
treatment processes will be considered on an individual basis, in
accordance with §290.39(l) of this title. Where innovative/alternate
treatment systems are proposed, the licensed professional engineer
must provide pilot test data or data collected at similar full-scale
operations demonstrating that the system will produce water that meets
the requirements of Subchapter F of this chapter. Pilot test data
must be representative of the actual operating conditions which can
be expected over the course of the year. The executive director may
require a pilot study protocol to be submitted for review and approval
prior to conducting a pilot study to verify compliance with the requirements
of §290.39(l) of this title and Subchapter F of this chapter.
The executive director may require proof of a one-year manufacturer's
performance warrantee or guarantee assuring that the plant will produce
treated water which meets minimum state and federal standards for
drinking water quality.
(1) Package-type treatment systems and their components
shall be subject to all applicable design criteria in this section.
(2) Bag and cartridge filtration systems or modules
installed or replaced after April 1, 2012, and used for microbiological
treatment, can receive up to 3.0-log Giardia removal
credit, up to 2.0-log Cryptosporidium removal
credit for individual bag or cartridge filters, and up to 2.5-log Cryptosporidium removal credit for bag or
cartridge filters operated in series only if the cartridges or bags
meet the criteria in subparagraphs (A) - (C) of this paragraph.
(A) The filter system must treat the entire plant flow.
(B) To be eligible for this credit, systems must receive
approval from the executive director based on the results of challenge
testing that is conducted according to the criteria established by
40 Code of Federal Regulations (CFR) §141.719(a) and the executive
director.
(i) A factor of safety equal to 1.0-log for individual
bag or cartridge filters and 0.5-log for bag or cartridge filters
in series must be applied to challenge testing results to determine
removal credit.
(ii) Challenge testing must be performed on full-scale
bag or cartridge filters, and the associated filter housing or pressure
vessel, that are identical in material and construction to the filters
and housings the system will use for removal of
Cryptosporidium and Giardia.
(iii) Bag or cartridge filters must be challenge tested
in the same configuration that the system will use, either as individual
filters or as a series configuration of filters.
(iv) Systems may use results from challenge testing
conducted prior to January 5, 2006, if prior testing was consistent
with 40 CFR §141.719, submitted by the system's licensed professional
engineer, and approved by the executive director.
(v) If a previously tested filter is modified in a
manner that could change the removal efficiency of the filter product
line, additional challenge testing to demonstrate the removal efficiency
of the modified filter must be conducted and results submitted to
the executive director for approval.
(C) Pilot studies must be conducted using filters that
will meet the requirements of this section.
(3) Membrane filtration systems or modules installed
or replaced after April 1, 2012, and used for microbiological treatment,
can receive Cryptosporidium and Giardia removal credit for membrane filtration
only if the systems or modules meet the criteria in subparagraphs
(A) - (F) of this paragraph.
(A) The membrane module used by the system must undergo
challenge testing to evaluate removal efficiency. Challenge testing
must be conducted according to the criteria established by 40 CFR §141.719(b)(2)
and the executive director.
(i) All membrane module challenge test protocols and
results, the protocol for calculating the representative Log Removal
Value (LRV) for each membrane module, the removal efficiency, calculated
results of Membrane LRVC-Test , and the non-destructive performance
test with its Quality Control Release Value (QCRV) must be submitted
to the executive director for review and approval prior to beginning
a membrane filtration pilot study at a public water system.
(ii) Challenge testing must be conducted on either
a full-scale membrane module identical in material and construction
to the membrane modules to be used in the system's treatment facility,
or a smaller-scale membrane module identical in material and similar
in construction to the full-scale module if approved by the executive
director.
(iii) Systems may use data from challenge testing conducted
prior to January 5, 2006, if prior testing was consistent with 40
CFR §141.719, submitted by the system's licensed professional
engineer, and approved by the executive director.
(iv) If a previously tested membrane is modified in
a manner that could change the removal efficiency of the membrane
product line or the applicability of the non-destructive performance
test and associated QCRV, additional challenge testing to demonstrate
the removal efficiency of the modified membrane and determine a new
QCRV for the modified membrane must be conducted and results submitted
to the executive director for approval.
Cont'd... |
