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IDEM Overview of March 14, IDEM Overview of March 14, 2008 Draft Antidegradation Rule2008 Draft Antidegradation Rule

Presented at the April 29, 2008 Presented at the April 29, 2008 Antidegradation Stakeholder Antidegradation Stakeholder

MeetingMeeting

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Refresher: Recent History of Refresher: Recent History of Antidegradation RulemakingAntidegradation Rulemaking

• April 2005 - IDEM determined the April 1, 2005 April 2005 - IDEM determined the April 1, 2005 second noticed draft would be difficult to second noticed draft would be difficult to implement.implement.

• April 2005 – July 2007 – internal IDEM, OWQ April 2005 – July 2007 – internal IDEM, OWQ workgroup met to take a fresh look at workgroup met to take a fresh look at antidegradation implementation procedures and antidegradation implementation procedures and develop revised concept.develop revised concept.

• Aug 2007 – Nov 2007 – IDEM staff presented Aug 2007 – Nov 2007 – IDEM staff presented revised concept to interested parties.revised concept to interested parties.

• Governor’s Stakeholder meeting – March 7, 2008.Governor’s Stakeholder meeting – March 7, 2008.• March 14, 2008 - Draft rule language based on March 14, 2008 - Draft rule language based on

revised concept circulated.revised concept circulated.

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Internal IDEM Internal IDEM antidegradation workgroup antidegradation workgroup

processprocess• Gathered information about antidegradation Gathered information about antidegradation

from other states and EPA;from other states and EPA;

• Reviewed comments received on the Reviewed comments received on the April 1, April 1, 2005 second noticed draft;2005 second noticed draft;

• Identified and focused on the key issues raised;Identified and focused on the key issues raised;

• Discussed potential ways to address the key Discussed potential ways to address the key issues;issues;

• Contributed to development of the Contributed to development of the March 14, March 14, 2008 draft rule language.2008 draft rule language.

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IDEM Goals for draft RuleIDEM Goals for draft Rule

• That the rule meet the requirements That the rule meet the requirements of the Clean Water Act; comply with of the Clean Water Act; comply with state law; and be consistent with state law; and be consistent with existing state administrative rules.existing state administrative rules.

• That the rule can be implemented by That the rule can be implemented by IDEM according to a clear, consistent, IDEM according to a clear, consistent, logical, and streamlined process.logical, and streamlined process.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 1: ApplicabilitySec 1: Applicability

• IDEM’s intent is to have the rule IDEM’s intent is to have the rule apply only when a new or increased apply only when a new or increased discharge triggers the need for a new discharge triggers the need for a new permit limit.permit limit.

• A new permit limit is needed when A new permit limit is needed when there is a reasonable potential to there is a reasonable potential to exceed (RPE) any narrative or exceed (RPE) any narrative or numeric water quality criterion.numeric water quality criterion.

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Reasonable Potential to ExceedReasonable Potential to Exceed327 IAC 5-2-11.1(h) & 327 IAC 5-2-11.5327 IAC 5-2-11.1(h) & 327 IAC 5-2-11.5

• The RPE process compares the projected The RPE process compares the projected effluent quality (PEQ) to the preliminary effluent quality (PEQ) to the preliminary effluent limit (PEL). effluent limit (PEL).

• If the projected effluent quality is greater If the projected effluent quality is greater than the preliminary effluent limit, then a than the preliminary effluent limit, then a permit limit is required.permit limit is required.

• The preliminary effluent limit is The preliminary effluent limit is influenced by the size of the mixing zone.influenced by the size of the mixing zone.

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Mixing ZonesMixing Zones327 IAC 2-1-4 & 327 IAC 5-2-11.4(b)(3)327 IAC 2-1-4 & 327 IAC 5-2-11.4(b)(3)

• No universal mixing zone may be prescribed. No universal mixing zone may be prescribed. • The Commissioner shall determine the The Commissioner shall determine the

mixing zone upon application by the mixing zone upon application by the discharger.discharger.

• For the Great Lakes Basin, preliminary For the Great Lakes Basin, preliminary wasteload allocations shall be calculated wasteload allocations shall be calculated using a dilution fraction using a dilution fraction no greater thanno greater than 25% 25% of the stream design flow (of the stream design flow (327 IAC 5-2-11.4327 IAC 5-2-11.4).).

• For the rest of the state, preliminary For the rest of the state, preliminary wasteload allocations shall be calculated wasteload allocations shall be calculated using a dilution fraction using a dilution fraction no greater thanno greater than 50% 50% of the stream design flow.of the stream design flow.

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Potential result of RPE Potential result of RPE

• If the new or increased discharge is If the new or increased discharge is too small to require a permit limit too small to require a permit limit based on RPE, then no based on RPE, then no antidegradation review is required.antidegradation review is required.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 2: DefinitionsSec 2: Definitions

• Many of the definitions are based on Many of the definitions are based on statutory definitions or definitions used in statutory definitions or definitions used in other rules.other rules.

• IDEM will review the definitions for IDEM will review the definitions for consistency of use within the rule itself consistency of use within the rule itself and other rules.and other rules.

• IDEM will eliminate definitions if the term IDEM will eliminate definitions if the term is not actually used within the rule.is not actually used within the rule.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 3: Antidegradation Sec 3: Antidegradation

StandardsStandards• Establishes minimum standards based on Tiers.Establishes minimum standards based on Tiers.

• All waters are presumed to be high quality All waters are presumed to be high quality waters (better quality than the water quality waters (better quality than the water quality criterion), including OSRWs and EUWs.criterion), including OSRWs and EUWs.

• However, OSRWs and EUWs are subject to the However, OSRWs and EUWs are subject to the Tier 2.9 antidegradation standard, particularly, Tier 2.9 antidegradation standard, particularly, no new or increased loading of BCCs that no new or increased loading of BCCs that causes a significant lowering of water quality.causes a significant lowering of water quality.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 4: Non Significant Sec 4: Non Significant

LoweringLowering• Identifies activities that, although they may Identifies activities that, although they may

result in a new or increased discharge, the result in a new or increased discharge, the discharge is at a level that will not cause a discharge is at a level that will not cause a significant lowering of water quality.significant lowering of water quality.

• For activities that qualify, no further For activities that qualify, no further antidegradation review is required.antidegradation review is required.

• These activities do not include BCCs, These activities do not include BCCs, however IDEM is concerned about however IDEM is concerned about antidegradation implementation for mercury.antidegradation implementation for mercury.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 5: NSL JustificationSec 5: NSL Justification

• The applicant must demonstrate that The applicant must demonstrate that their proposed discharge is a non their proposed discharge is a non significant lowering activity.significant lowering activity.

• Question: Should this review be Question: Should this review be combined with the review of the combined with the review of the application for the associated NPDES application for the associated NPDES permit?permit?

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 6: De minimisSec 6: De minimis

• 2 Options for non OSRW/EUW:2 Options for non OSRW/EUW:– Option 1: The more stringent of the WQBEL Option 1: The more stringent of the WQBEL

calculated without the benefit of a mixing zone or calculated without the benefit of a mixing zone or default technology based effluent limit. default technology based effluent limit.

– Option 2: less than 10% of the unused loading Option 2: less than 10% of the unused loading capacity.capacity.

• For OSRW/EUW de minimis is the For OSRW/EUW de minimis is the representative background representative background concentration.concentration.

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Option 1: No mixing zone or Option 1: No mixing zone or default technology based default technology based

effluent limiteffluent limit• Less data are needed to calculate a WQBEL Less data are needed to calculate a WQBEL

without a mixing zone.without a mixing zone.

• Default technology based effluent limits may Default technology based effluent limits may be difficult to derive as the federal effluent be difficult to derive as the federal effluent guidelines are insufficient (nonexistent or guidelines are insufficient (nonexistent or out-of-date for many parameters).out-of-date for many parameters).

• Option 1 results in a consistent de minimis Option 1 results in a consistent de minimis level as the calculation is independent of level as the calculation is independent of available receiving stream background data.available receiving stream background data.

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Option 2: Less than 10% of the Option 2: Less than 10% of the unused loading capacityunused loading capacity

• Unused loading capacity is calculated Unused loading capacity is calculated similar to how RPE is calculated.similar to how RPE is calculated.

• Sufficient data are needed to Sufficient data are needed to determine the representative determine the representative background concentration and background concentration and loading capacity of a receiving loading capacity of a receiving stream.stream.

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Option 2: Less than 10% of the Option 2: Less than 10% of the unused loading capacity unused loading capacity

(cont’d)(cont’d)• If a mixing zone was used to calculate If a mixing zone was used to calculate

RPE, then it should be considered RPE, then it should be considered when determining if a discharge is de when determining if a discharge is de minimis.minimis.

• Option 2 will result in different de Option 2 will result in different de minimis levels depending on available minimis levels depending on available receiving stream background data receiving stream background data and the size of the receiving stream.and the size of the receiving stream.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 7: significant loweringSec 7: significant lowering

• Discharges that have a reasonable Discharges that have a reasonable potential to exceed and are greater potential to exceed and are greater than de minimis are a significant than de minimis are a significant lowering…lowering…

• unless it is an activity listed in 4b unless it is an activity listed in 4b (not 4c as typo indicates).(not 4c as typo indicates).

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 8: Necessary TestSec 8: Necessary Test

• A successful necessary test should show:A successful necessary test should show:– why the discharge is necessary at all; andwhy the discharge is necessary at all; and– that the discharge is providing a social or that the discharge is providing a social or

economic benefit. economic benefit.

• Cost-effective pollution prevention must Cost-effective pollution prevention must be applied to minimize the discharge.be applied to minimize the discharge.

• Question: Should the question of “why Question: Should the question of “why the discharge is necessary at all” be the discharge is necessary at all” be answered separately?answered separately?

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 9: Alternatives AnalysisSec 9: Alternatives Analysis

• If the discharge is necessary for If the discharge is necessary for providing a social or economic benefit providing a social or economic benefit but cannot meet the default technology but cannot meet the default technology based effluent limits, then the applicant based effluent limits, then the applicant must examine alternative levels of must examine alternative levels of treatment.treatment.

• The alternatives analysis should The alternatives analysis should compare level of treatment with the cost compare level of treatment with the cost of treatment – a “knee-of-the curve” of treatment – a “knee-of-the curve” type analysis.type analysis.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 10: IDEM ReviewSec 10: IDEM Review

• IDEM will provide opportunity for public IDEM will provide opportunity for public comment on the necessary test and comment on the necessary test and alternative treatment analysis.alternative treatment analysis.

• IDEM will evaluate the necessary test IDEM will evaluate the necessary test and alternative treatment analysis to and alternative treatment analysis to determine if the proposed significant determine if the proposed significant lowering of water quality is necessary lowering of water quality is necessary and provides a social or economic and provides a social or economic benefit.benefit.

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March 14, 2008 draft ruleMarch 14, 2008 draft ruleSec 11: W Q Improvement Sec 11: W Q Improvement

ProjectProject• A water quality improvement project is A water quality improvement project is

required to offset the impact of any required to offset the impact of any significant lowering of water quality in an significant lowering of water quality in an OSRW or EUW.OSRW or EUW.

• Complete information on a proposed water Complete information on a proposed water quality improvement project must be quality improvement project must be submitted whether implementing the project submitted whether implementing the project or funding the project by paying a fee.or funding the project by paying a fee.

• IDEM will provide opportunity for public IDEM will provide opportunity for public comment on the proposed water quality comment on the proposed water quality improvement project.improvement project.

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Other issues not addressed in Other issues not addressed in March 14, 2008 draft ruleMarch 14, 2008 draft rule

• General permitsGeneral permits– IDEM believes that the discharges permitted IDEM believes that the discharges permitted

under the general permit rules should not under the general permit rules should not cause a significant lowering of water quality.cause a significant lowering of water quality.

– IDEM will review the permit conditions found IDEM will review the permit conditions found in the general permit rules to determine if:in the general permit rules to determine if:•they cause a significant lowering of water quality;they cause a significant lowering of water quality;•any changes are needed to the general permit any changes are needed to the general permit

rules to address any pollutant of concern and/or rules to address any pollutant of concern and/or effluent limitations/conditions that may cause a effluent limitations/conditions that may cause a significant lowering of water quality.significant lowering of water quality.

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Other issues not addressed in Other issues not addressed in March 14, 2008 draft ruleMarch 14, 2008 draft rule

• 401 Water Quality Certifications401 Water Quality Certifications– IDEM’s requirement for mitigation to IDEM’s requirement for mitigation to

offset discharge impacts authorized by a offset discharge impacts authorized by a 401 water quality certification ensures 401 water quality certification ensures that these discharges do not result in a that these discharges do not result in a significant lowering of water quality. significant lowering of water quality.

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Proposed Antidegradation Proposed Antidegradation Implementation Procedural Implementation Procedural

StepsSteps