Ventaloro Presentation

Update on the 2023-2025 Surface Water Standards
Triennial Review (Information Item)
Water Quality Committee
November 8, 2023
Christopher Ventaloro, NCDEQ Classifications, Standards & Rules Review Branch
Outline
Review water quality standards
rulemaking process
Describe proposed rule changes
Review triennial review rulemaking & timeline
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The Water Quality Standards Process
3
ImplementStandardDesignated
Use Criteria
Triennial Review = rule making process by which
protective criteria are adopted into state rule
Surface Water Standard Rulemaking Process
Development
•Staff review current standards, available EPA guidance & literature and develop rulemaking package
•Staff present proposed amendments to Environmental
Management Commission (WQC/EMC) for approval to proceed
State
Approval
•EMC adoption
•RRC approval
•NC Attorney General sign off
Federal Approval
•EPA Clean Water Act review
•Endangered Species Act consultation
•NC notified of approval/disapproval
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2023-2025 Triennial – Focus Topics
•Updated human health exposure factors (EFs)
•Updated human health criteria
•E. coli criteria for Class B (primary recreation) waters
•Update variance language (per EPA)
•Technical corrections
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Updated Human Health Exposure Factors
•Exposure factors are part of the narrative standard for toxic substances in 02B .0208
•Used to calculate fish consumption & water supply standards for
substances that do not have existing 02B numeric standards
•Example calculation from 02B .0208:
***Exposure factors highlighted in red***
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WQS = Water Quality Standard
RfD = Reference Dose
RSC = Relative Source Contribution
BW = Body Weight
WCR = Water Consumption Rate
FCR = Fish Consumption Rate
BCF = Bioconcentration Factor
𝑊𝑊𝑊𝑊𝑊𝑊=𝑅𝑅𝑅𝑅𝑅𝑅× 𝑅𝑅𝑊𝑊𝑅𝑅× 𝐵𝐵𝑊𝑊𝑊𝑊𝑅𝑅𝑅𝑅+(𝐹𝐹𝑅𝑅𝑅𝑅 𝑥𝑥 𝐵𝐵𝑅𝑅𝐹𝐹)
Updated Human Health Exposure Factors
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Exposure Factor Current 02B Value1 2015 EPA Value2
Body Weight (kg)70 80
Drinking Water Intake Rate
(L/day)3 2.0 2.4
Fish Consumption Rate (g/day)17.5 22.0
Footnotes:
1.Established in 02B .0208 in 1989 (Eff. 10/01/89); Fish consumption updated in 2007 (Eff.
05/01/07)
2.Based on exposure of adults aged 21 and older (data from CDC national health surveys)
3.15A NCAC 02B .0208 refers to this as the “Water Consumption Rate”
Updated Human Health Criteria
•2015 – EPA published updated human health NRWQC* for 94 chemicals
•Human health refers to:
•Consumption of fish tissue
•Protections for water supplies
•Updates incorporated:
•Updated toxicity factors (Reference Doses & Cancer values)
•Inclusion of Relative Source Contributions (RSCs)
•Updated toxicity exposure factors
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* National Recommended Water Quality Criteria
Updated Human Health Criteria
•Focus on chemicals with existing 02B standards
•14 updated EPA chemicals that correspond to:
o 26 existing 02B standards
12 fish consumption (02B .0208)
14 water supply (Class WS)
*Note: Remainder of updated criteria addressed in next triennial review*
**Any updated EPA criteria not adopted in this rulemaking are available for use
via the narrative standard for toxic substances**
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Chemical
Current Fish
Consumption
Standard (ug/L)
Current Water
Supply Standard
(ug/L)
Proposed Fish
Consumption
Standard (ug/L)
Proposed Water
Supply Standard
(ug/L)
Rules Affected
1,1,2,2-Tetrachloroethane 4 0.17 3 0.2 .0208, .0212-.0218
2,4-D N/A 70 N/A 1,300 .0212-.0218
Aldrin 0.00005 0.00005 0.00000077 0.00000077 .0208, .0212-.0218
Benzene 51 1.19 25 0.9 .0208, .0212-.0218
Carbon Tetrachloride 1.6 0.254 5 0.4 .0208, .0212-.0218
Chlordane 0.0008 0.0008 0.00032 0.00031 .0208, .0212-.0218
DDT 0.0002 0.0002 0.00003 0.00003 .0208, .0212-.0218
Dieldrin 0.00005 0.00005 0.0000012 0.0000012 .0208, .0212-.0218
Heptachlor 0.00008 0.00008 0.0000059 0.0000059 .0208, .0212-.0218
Hexachlorobutadiene 18 0.44 0.01 0.01 .0208, .0212-.0218
Silvex (2,4-TP)N/A 10 N/A 100 .0212-.0218
Tetrachloroethylene 3.3 0.7 29 10 .0208, .0212-.0218
Trichloroethylene (TCE)30 2.5 7 0.6 .0208, .0212-.0218
Vinyl Chloride 2.4 0.025 1.6 0.022 .0208, .0212-.0218
= Proposed standard is higher = Proposed standard is lower
EPA Recommended Bacteria Criteria
for Primary Recreation Waters
•In 2012, EPA published updated bacterial indicator criteria
for primary1 recreation waters (E. Coli or Enterococcus)
•Recommends either of two geomeans associated with different estimated illness rates and an associated Statistical
Threshold Value (STV)
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Illnesses
(per 1,000 primary
contact recreators)
GeoMean2
(per 100 ml)
10% Exceedance
(per 100 ml)
20% Exceedance
(per 100 ml)
36 126 CFU 410 CFU 274 CFU
32 100 CFU 326 CFU 217 CFU
1 In NC, primary recreation freshwaters are classified as Class B [15A NCAC 02B .0219(1)]
2 Geometric mean based on five samples taken over a 30-day period are referred to as “5-in-30’s”
NC Primary Recreation Bacteria Study
•2022-2023: DEQ conducted a statewide fecal coliform
and E. coli study to inform standard and RIA development
Ambient Monitoring Stations
•24 stations on Class B freshwaters
•Sampled:
•August – October 2022
•April – August 2023
•Each station sampled 5 times per
month
•One “5-in-30A” per station per calendar
month
NPDES Dischargers
•20 dischargers
•Sampled:
•April – August 2023
•Each discharger sampled effluent
from their facility
•Effluent data is currently being
evaluated
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A Geometric mean based on five samples taken over a 30-day period are referred to as “5-in-30’s”
NC Bacteria Study – Ambient Results
Standard # of
Stations
Exceeds fecal (>20% >400 or geomeanA >200)16
Exceeds E. coli (>10% >410 or geomeanA >126)17
Exceeds E. coli (>20% >274 or geomeanA >126)13
Exceeds E. coli (>10% >326 or geomeanA >100)18
Exceeds E. coli (>20% >217 or geomeanA >100)15
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A Geometric mean based on five samples taken over a 30-day period are referred to as “5-in-30’s”
NC Proposed E. coli Standard
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GeoMeanA
(per 100 ml)
20% Exceedance
(per 100 ml)
126 CFU 274 CFU
A Geometric mean based on five samples taken over a 30-day period are referred to as “5-in-30’s”
Update Language for Variances
•02B .0226 – Exemptions From Surface Water Quality Standards
•Current language:
•Variances from applicable standards, revisions to water quality standards or
site-specific water quality standards may be granted by the Commission on a
case-by-case basis pursuant to G.S.143-215.3(e), 143-214.3 or 143-214.1.
•EPA requested states update rule language to either:
•Reference 40 CFR §131.14 or
•Provide language specifying the requirements for variances per §131.14
•Staff propose adding reference to 40 CFR §131.14
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Technical Corrections
•Rules being reviewed to determine if technical corrections
are needed
•Minor corrections including:
Typographical errors (typos)
Incorrect rule references
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2023-2025 Triennial – Next Steps
•Develop rule language and supporting materials
•Development of Regulatory Impact Analysis (RIA)
•Return to Water Quality Committee to begin rulemaking
process – January 2024
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Rulemaking Timeline
WQC Info Item
November 2023
WQC Approval to Proceed
Jan 2024
EMC Approval to Notice
March 2024
File for NC Register
Publication
March 2024
Notice of Text / Public
Comment period begins
mid-April 2024
Public Hearing1
June 2024
End of Public Comment period2
mid-June 2024
EMC Adoption
November 2024
Per federal Clean Water Act:
1 At least 45-days from Public Notice
Per NC Administrative Procedures Act:
2 At least 60-days from Public Notice
Surface Water Quality Standards Contacts
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Elizabeth Kountis
Water Quality Standards Coordinator
Phone: [phone]
[e-mail]
DWR Classifications, Standards & Rules Review website:
https://deq.nc.gov/about/divisions/water-resources/planning/classification-standards
Susan Meadows
Water Quality Standards Assistance
Phone: [phone]
[e-mail]
Paul Wojoski
Classifications & Standards Branch Supervisor
Phone: [phone]
[e-mail]
Christopher Ventaloro
Water Quality Standards Coordinator
Phone: [phone]
[e-mail]