Ohio Administrative Code › Title 3745 - Ohio Environmental Protection Agency › Chapter 3745-81 - Primary Drinking Water Rules › Section 3745-81-68 - Microbial toolbox options for meeting Cryptosporidium treatment requirements

Current through all regulations passed and filed through July 1, 2024
(A) Water systems shall obtain plan approval
			 by the director for each microbial toolbox option prior to receiving treatment
			 credit for the toolbox option. Systems receive the treatment credits listed in
			 the following table by meeting the conditions for microbial toolbox options
			 described in paragraphs (B) to (N) of this rule. Systems shall apply these
			 treatment credits to meet the treatment required by paragraph (E) of rule
			 3745-81-67
			 of the Administrative Code. The following table summarizes options in the
			 microbial toolbox:
MICROBIAL TOOLBOX SUMMARY TABLE: OPTIONS, TREATMENT CREDITS AND
				CRITERIA
Toolbox Option
Cryptosporidium treatment credit with design and
						  implementation criteria
Source Protection and Management Toolbox
						  Options
(1) Watershed control program...
0.5 -log credit for director-approved program
						  comprising required elements, annual program status report to director, and
						  regular watershed survey. Specific criteria are in paragraph (B) of this
						  rule.
(2) Alternative source/intake
						  management...
No prescribed credit. Systems may conduct simultaneous
						  monitoring for treatment bin classification at alternative intake locations or
						  under alternative intake management strategies. Specific criteria are in
						  paragraph (C) of this rule.
Pre Filtration Toolbox Options
(3) Presedimentation basin with
						  coagulation...
0.5 -log credit during any month that presedimentation
						  basins achieve a monthly mean reduction of 0.5 -log or greater in turbidity or
						  alternative director-approved performance criteria. To be eligible, basins
						  shall be operated continuously with coagulant addition and all plant flow shall
						  pass through basins. Specific criteria are in paragraph (D) of this
						  rule.
(4) Two-stage lime softening...
0.5 -log credit for two-stage softening where chemical
						  additional and hardness precipitation occur in both stages. All plant flow
						  shall pass through both stages. Singlestage softening is credited as equivalent
						  to conventional treatment. Specific criteria are in paragraph (E) of this
						  rule.
(5) Bank filtration...
0.5 -log credit for 25-foot setback; 1.0 -log credit
						  for 50-foot setback; aquifer shall be unconsolidated sand containing at least
						  10 per cent fines; average turbidity in wells shall be less than 1 NTU. Systems
						  using wells followed by filtration when conducting source water monitoring
						  shall sample the well to determine bin classification and are not eligible for
						  additional credit. Specific criteria are in paragraph (F) of this
						  rule.
Treatment Performance Toolbox Options
(6) Combined filter performance...
0.5 -log credit for combined filter effluent turbidity
						  less than or equal to 0.15 NTU in at least 95 per cent of measurements each
						  month. Specific criteria are in paragraph (G) of this rule.
(7) Individual filter performance...
0.5 -log credit (in addition to 0.5 -log combined
						  filter performance credit) if individual filter effluent turbidity is less than
						  or equal to 0.15 NTU in at least 95 per cent of samples each month in each
						  filter and is never greater than 0.3 NTU in two consecutive measurements in any
						  filter. Specific criteria are in paragraph (H) of this rule.
(8) Demonstration of performance...
Credit awarded to unit process or treatment train based
						  on a demonstration to the director with a director-accepted protocol. Specific
						  criteria are in paragraph (I) of this rule.
Additional Filtration Toolbox Options
(9) Bag or cartridge filters (individual
						  filters)...
Up to 2-log credit based on the removal efficiency
						  demonstrated during challenge testing with a 1.0 -log factor of safety.
						  Specific criteria are in paragraph (J) of this rule.
(10) Bag or cartridge filters (in
						  series)...
Up to 2.5 -log credit based on the removal efficiency
						  demonstrated during challenge testing with a 0.5 -log factor of safety.
Specific criteria in paragraph (J) of this
						  rule.
(11) Membrane filtration...
Log credit equivalent to removal efficiency
						  demonstrated in challenge test for device if supported by direct integrity
						  testing. Specific criteria are in paragraph (K) of this rule.
(12) Second stage filtration...
0.5 -log credit for second separate granular media
						  filtration stage if treatment train includes coagulation prior to first filter.
						  Specific criteria are in paragraph (L) of this rule.
(13) Slow sand filters....
2.5 -log credit as a secondary filtration step; 3.0
						  -log credit as a primary filtration process. No prior chlorination for either
						  option. Specific criteria are in paragraph (M) of this rule.
Inactivation Toolbox Options
(14) Chlorine dioxide...
Log credit based on measured CT in relation to CT
						  table. Specific criteria in paragraph (N)(2) of this rule.
(15) Ozone...
Log credit based on measured CT in relation to CT
						  table. Specific criteria in paragraph (N)(2) of this rule.
(16) UV...
Log credit based on validated UV dose in relation to UV
						  dose table; reactor validation testing required to establish UV dose and
						  associated operating conditions. Specific criteria in paragraph (N)(4) of this
						  rule.
(B)
			 Watershed control program.
Systems received 0.5 -log Cryptosporidium treatment credit for
				implementing a watershed control program that meets the
				following :
(1)
			 Systems that intend to apply for the watershed control program credit shall
			 notify the director of this intent no later than two years prior to the
			 treatment compliance date applicable to the system in paragraph (F) of rule
			 3745-81-67
			 of the Administrative Code.
(2)
			 Systems shall submit to the director a proposed watershed control plan no later
			 than one year before the applicable treatment compliance date in paragraph (F)
			 of rule
			 3745-81-67
			 of the Administrative Code. The director shall approve the watershed control
			 plan for the system to receive watershed control program treatment credit. The
			 watershed control plan shall include the following elements:
(a) Identification of an area of influence
			 outside of which the likelihood of Cryptosporidium or fecal contamination
			 affecting the treatment plant intake is not significant as approved by the
			 director. This is the area to be evaluated in future watershed surveys in
			 accordance with paragraph (B)(4)(b) of this rule. The area of influence shall
			 include, at a minimum, the following:
(i) For systems using inland streams,
			 reservoirs, and lakes, the drinking water source protection area with primary
			 focus on the corridor management zone and any additional areas within the
			 watershed that have been specifically identified by the public water system or
			 the director as possible sources of Cryptosporidium.
(ii) For systems using the Ohio river, the
			 zone of critical concern.
(iii) For
			 systems using lake Erie, the potential influence zone, where this zone has been
			 delineated.
(b)
			 Identification of both potential and actual sources of Cryptosporidium
			 contamination and an assessment of the relative impact of these sources on the
			 system's source water quality.
(c)
			 An analysis of the effectiveness and feasibility of control measures that could
			 reduce Cryptosporidium loading from sources of contamination to the system's
			 source water.
(d) A statement of
			 goals and specific actions the system will undertake to reduce source water
			 Cryptosporidium levels. The plan shall explain how the actions are expected to
			 contribute to specific goals, identify watershed partners and their roles,
			 identify resource requirements and commitments, and include a schedule for plan
			 implementation with deadlines for completing specific actions identified in the
			 plan.
(3) Systems with
			 existing watershed control programs (i.e., programs in place on January 5,
			 2006) are eligible to seek this credit. the watershed
			 control plans shall meet the criteria in paragraph (B)(2) of this rule and
			 shall specify ongoing and future actions that will reduce source water
			 Cryptosporidium levels.
(4) Systems
			 shall complete the following actions to maintain the 0.5 -log credit.
(a) Submit an annual watershed control
			 program status report to the director. The annual watershed control program
			 status report shall do the following:
(i)
											Describe the system's implementation of the approved
			 plan and assess the adequacy of the plan to meet the goals.
(ii)
											Explain how the
			 system is addressing any shortcomings in plan implementation, including those
			 previously identified by the director or as the result of the watershed survey
			 conducted under paragraph (B)(4)(b) of this rule.
(iii)
											Describe any
			 significant changes that have occurred in the watershed since the last
			 watershed sanitary survey.
(b)
										If a system
			 determines during implementation that making a significant change to
			 the
			 system's approved watershed control program is necessary, the system
			 shall notify the director prior to making any such changes. If any change is
			 likely to reduce the level of source water protection, the system shall also
			 list in the notification the actions the system will take to
			 mitigate this effect.
(c) Undergo a watershed
			 sanitary survey every three years for community water systems and every five
			 years for non-community water systems and submit the survey report to the
			 director. The survey shall be conducted according to Ohio environmental
			 protection agency guidelines and by persons acceptable to the director.
(i) The watershed sanitary survey shall meet
			 the following criteria:
(a)
												Encompass the region identified in the
			 director-approved watershed control plan as the area of
			 influence.
(b)
												Assess the implementation of actions to reduce source
			 water Cryptosporidium levels.
(c)
												Identify any
			 significant new sources of Cryptosporidium.
(ii) If the director determines that
			 significant changes may have occurred in the watershed since the previous
			 watershed sanitary survey, systems shall undergo another watershed sanitary
			 survey by a date the director requires, which may be earlier than the regular
			 date in paragraph (B)(4)(b) of this rule.
(d) The system shall
			 make the watershed control plan, annual status reports, and watershed sanitary
			 survey reports available to the public upon request. These documents shall be
			 in a plain language style and include criteria by which to evaluate the success
			 of the program in achieving plan goals. The director may accept systems to
			 withhold from the public portions of the annual status report, watershed
			 control plan, and watershed sanitary survey based on water supply security
			 considerations.
(5) If
			 the director determines that a system is not carrying out the approved
			 watershed control plan, or if conditions change from those approved, the
			 watershed control plan may no longer be approvable. An approvable plan
			 shall be
			 submitted to maintain the watershed control program treatment credit.