1. NC Assessment Methodology
Kathy Stecker
Cam McNutt
DWQ Planning Section
To protect and enhance North Carolina's surface water and groundwater resources for the citizens of North Carolina and future generations.

2. Regulatory Overview Water Quality Standards
Uses + Criteria to protect uses
Numeric & narrative criteria
§303(d) CWA and 40 CFR 130.7
“Water quality standards”

3. NC’s Assessment Methodology
Uses and criteria
Aquatic Life
Numeric + narrative criteria
Recreation
Shellfish Consumption
Narrative criteria
Fish Consumption
Water Supply
Numeric criteria

4. Benthic Macroinvertebrates
Data Coordination
Benthic Macroinvertebrates
Fish Community
ESS
Ambient Data
Reservoir/Lake Data
DWQ Planning
Coalition Data
Integrated Report
303(d) and 305(b)
Shellfish Data
State
Agencies
Assessment
And AU Assignment
Beach Mon
Other DWQ Data
Fish Consumption
Where do the data and information come from to assess water quality in NC?
In order to assess the five USCs DWQ uses a lot of data.
Jay Sauber for ESS provided an overview of DWQ monitoring programs which make up the bulk of the data used for assessment.
Data are also assessed from several other federal, state, local government and universities as well.
During the 5-year assessment period 500,000 to 1 million observations from around 1,000 locations in NC are used for the assessment.
The data are summarized by station and assigned to a spot on earth (AU or water)-green box. If criteria are exeeded a water is impaired if criteria are not exceeded the water is supporting.
What happens in the blue square is what I will be talking about for the next few minutes
USGS/EPA/NRCS
Others
Universities
Local Governments
Utilities

5. Aquatic Life Assessment
Biological Integrity
(Narrative Criteria)
Chemistry Data
(Numeric Criteria)
Benthos
Fish Community
Excellent, Natural, Good, Good-Fair
Bioclassifications
Excellent, Good, Good-Fair
Bioclassifications
Less than 10% Exceedance of Standards
Supporting
Explain slide blue vs Red and potential for gray areas.
Aquatic life is assessed using both narrative and numeric aquatic life criteria. Standards Assessment methodology is sometimes different than the standard to allow for outliers, extreme conditions, errors.
Aus (waters) assessed for aquatic life use have at least one of these data types and can have as many as 15 to 20 parameters with criteria to assess the aquatic life use.
If any of the chemical or physical parameters are exceeded in greater than 10% of samples the water is impaired for that paramater. (N=100 example and bioclass example). There are exceptions to this as you will see later.
Not all aquatic life parameters with criteria have been assessed until recently.
In 2004 EPA required a change in how turbidity was assessed. There was also a contested case before the EMC regarding turbidity exceedances. Turbidity and all aquatic life parameters are assessed independently of each other now, consistent with CWA. If any one of the parameters exceeds the assessment criteria then the water is impaired for that parameter.
In 2003 the emc provided guidance to DWQ to approve benthos swamp criteria for use in assessing waters in the eastern basins. The Natural, Moderate and Severe bioclassifications are now used when assessing swamplike waters in eastern NC. Previously these waters were not rated.
Impaired
Poor, Fair or Severe Bioclassifications
Poor, Fair or Bioclassifications
Greater than 10% Exceedance of Standards

6. Biological Integrity
“The ability of an aquatic ecosystem to support and maintain a balanced and indigenous community of organisms having species composition, diversity, population densities, and functional organization similar to that of reference conditions.”
(15A NCAC 02B .0200)
What is biological integrity.
Measured using benthos and fish community data- point to narrative standard
Jay presented an overview of these programs to the EMC a few months ago.
These data are widely used and very good indicators of aquatic life biological integrity. They are direct measure of aquatic life health.
They provide us with not only impaired or supporting waters but also waters with excellent water quality as well as the degree of impairment.
From the previous slide a Good-Fair or

7. Estuarine/ocean waters
Recreation Assessment
Swimming Advisories
(Narrative Criteria)
Pathogen Indicators
(Numeric Criteria)
Fresh waters
Estuarine/ocean waters
Fecal Coliform Bacteria
Enterrococci
Geometric Mean less than 200 and
Geometric Mean less than 35
Less than 61 advisory days
Supporting
Less than 20% above 400
Geometric Mean greater than 200
Recreation is assessed using both numeric and narrative criteria.
Monthly data are collected at the 600 or so chemistry stations and more frequently at beach stations during swimming season.
These criteria are only used for Impairments when the there are 5 samples in a 30 day period.
The narrative criteria used here are usually associated with data-high pathogen levels= advisory posting.
When there are no pathogen indicator data available but the advisory posting criterion is exceeded the water is impaired for recreation based on advisory postings- a loss of use.
Impaired
Geometric Mean greater than 35
Greater than 61 advisory days
Or greater than 20% above 400

8. WS Classified waters only
Water Supply Assessment
Chemistry Data
(Numeric Criteria)
Less than 10% Exceedance of Standards
Supporting
The Water supply use is assessed only in waters classified for the water supply use.
Only numeric criteria are used to assess the water supply use.
Aquatic life and recreation uses and criteria are also assessed in WS waters when data are available to assess these uses.
Impaired
Greater than 10% Exceedance of Standards
WS Classified waters only

9. Shellfish Harvesting Assessment
SA Classified waters only
Growing Area Classification
(Narrative Criteria)
Approved for Shellfish Harvesting
Supporting
The shellfish harvesting use is assessed only in waters classified for Shellfish harvesting.
Growing area classifications are based on fecal coliform data and sanitary surveys performed by DEH SS.
The DEH growing area fecal coliform criteria are the same as the DWQ SA water quality standards.
Aquatic life and recreation uses and criteria are also assessed in SA waters when data are available to assess these uses.
In the early part of this century DWQ changed its methodology so that all non approved waters would be impaired. Previously conditional waters were assessed as supporting.
This change in assessment method was encouraged by the CRC and MFC and approved by the EMC during the WOK basin plan approval process in October 2001
Impaired
Not Approved for Shellfish Harvesting

10. Fish Consumption Assessment
Fish Consumption Advisories
(Narrative Criteria)
No Fish Consumption Advisory
Supporting
Fish consumption use assessment is based on DHHS site specific advisories and statewide advice for mercury in fish tissue.
The advisories and advice are based on fish tissue data collected by DWQ as well as epidemiological analyses.
Over the last 10 years the mercury assessment has progressed from site specific advisories for bowfin in eastern waters to statewide advice for LMB as more data have been collected showing elevated levels in different species across the state.
Impaired
Site Specific Consumption Advisory
Statewide Mercury Consumption Advice

11. It’s not just about Impairment
How is Impairment Determined?
It’s not just about Impairment 1 2 3 4 5
NC Impaired Waters List
303(d) List
Integrated Report
305(b) Report
As you have seen in the last few slides a lot of data and information are used to assess the five uses in NC. Each assessment is assigned to one of these integrated report categories. Assessments in category 1 are supporting and 4 and 5 are impaired. Category 5 Impaired assessments are those that require TMDLs. Category 4 Impaired assessments either have a TMDL or some other strategy in place to address the identified impairment. Most waters in NC are not assessed and placed in category 3. As you will see in the next busy slide there are many ways during the assessment of an individual parameter on a given water body to not make an impaired assessment.

12. Dissolved Oxygen Assessment Method- Aquatic Life
DO Data
Available
Dissolved Oxygen Assessment Method- Aquatic Life
DO<EL in
>10% of N 3c
N>9
Supporting 1
Class Sw
Not Rated 3
Swamp
Biocriteria
Impaired
Biology
Swamp
Like*
BOD
Source
Not Rated 3
Not Rated 3
Receives Significant
Swamp Drainage
Not Rated 3
This is the decision tree for Dissolved oxygen assessment. This is used at each of the 600 or so stations to make a determination of whether dissolved oxygen standard is being exceeded thus impairing the aquatic life use. The rectangular boxes indicate an end point in the assessment and assignment to one of the integrated report categories from the previous slide. Note here that the first box allows for a 10% exceedance of the standard to allow for outliers, extreme events, instrument error. There are 11 potential asmnts decisions that can be made at each station where dissolved oxygen data are collected. Two of these (in red) result in an impaired assessment for Dissolved oxygen. There is one supporting (meeting the standard) assessment decision and 8 different ways to categorize the water as Not Rated because the data and information are not conclusive enough to make a decision as to whether the water is supporting or impaired for DO. Each of these assessment endpoint categories has some followup mechanism so that in a future assessment a use support rating can be assigned. One of the followup processes is to determine if the exceedances are due to natural conditions. If this is the case then documentation is provided and the water is assesses as supporting.
Not Rated 3
Not Rated 3
Drainage via
Ditches
Impaired 5
BOD
Source
Not Rated 3
Impaired 5
Not Rated 3

13. 2-Year 303(d) Cycle April 1 - Submit list Internal Review Assessment
Data Delivery
Even Year
Public Review
Odd Year
April 1 - Submit list
Review Assessment Methods

14. 2-Year 303(d) Cycle April 1 - Submit list 2012 List You are here
Internal Review
Assessment
Data Delivery
Even Year
Public Review
Odd Year
April 1 - Submit list
Review Assessment Methods

15. EPA’s Role EPA must approve or disapprove list
EPA does not approve or disapprove assessment methodology, but
If they disagree with state decisions…
…they add waters

16. “De-Listing” Start with previous approved list
Good cause (40 CFR 130.7)
Standards attained
TMDL or other enforceable strategy

17. Public Review & Comment
Public notice required
Typical comments
Recommend additional listings
Recommend de-listings
Requests for clarifications
Pollutant source information
Requests for further study

18. More Information Assessment Methodology 2010 Final 303(d) List
Responsiveness Summaries

19. QUESTIONS?
To protect and enhance North Carolina's surface water and groundwater resources for the citizens of North Carolina and future generations.

20. RESERVE

21. Regulatory Overview §303(d) CWA & 40 CFR 130.7 1991 EPA Policy
“any water quality standard”
1991 EPA Policy
“independently sufficient evidence” of impairment
2011 Anacostia River case (ANACOSTIA RIVERKEEPER v. JACKSON, US District Court, DC, July 25, 2011)
Waterbody impaired and listed if any water quality standard not met

22. NC’s Assessment Methodology
Same for approved 2008 and 2010 lists
Same as reported in basin plans
Extensive internal review
Negotiations w/EPA, EPA reviews

23. Other States’ Assessment Methodologies
Reflect their water quality standards
Examples
10%
Statistical tests
Minimum number of samples
Assessment methodology in rule
“Credible data” laws
Volunteer monitoring

24. 2014 303(d) List Data from 2008-2012 AM review May-Sept. 2012
EPA guidance Fall 2012

25. Mercury TMDL Background