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N.C. Department of Environment and Natural Resources

NC Department of Environment and Natural Resources
Water Quality - Approved Methods Info

Water Quality

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Additional Information About Method and Parameter Approvals

This page lists letters and memorandums of approval for methods by various authorities including the Director of the Division of Water Quality, EPA and the Division of Waste Management UST and Solid Waste Sections.

A Note About Individual Organic Analyte Certification

We often receive requests for certification for individual organic analytes. The NC WW/GW LC program is a method certification program and we do not certify for individual organic analytes. If the laboratory holds certification for a method in which the analyte is published within the scope of that method, the laboratory is considered to be certified for analysis of that analyte. In the case where the analyte of interest is not within the scope of a published certifiable method (an example of this would be Tetrahydrofuran by SW-846 Method 8260 B), the laboratory is advised to maintain Method Detection Limit (MDL) and Initial Demonstration of Capability (IDOC) study summary data on file at the laboratory and follow the quality control requirements outlined in the reference method. Any questions (such as whether an analyte of interest may be reported as a Tentatively Identified Compound [TIC] or whether is must be quantitated) should be directed to the regulatory agency receiving the data. This office does not have the authority to certify or otherwise offer any approval for analysis of individual analytes not within the scope of a certifiable method.

Ferrous Iron

The NC WW/GW LC program does not have the authority to certify specifically for the Ferrous state of Iron. We do certify for Total Iron by a method that also allows for measurement of the ferrous state (i.e., Standard Methods 3500-Fe B, 20th Edition and beyond). To measure the ferrous state, however, samples must be analyzed at the sampling site. The program will only certify:

  1. entities which intend to report Total Iron by this method, or
  2. entities which intend to report Ferrous Iron by this method and have the capability to analyze samples at the sampling location 

Data analyzed, reported and qualified as out of hold time is unusable for the regulatory data receivers' objectives. 

For Approved Procedures for the Analysis of Field Parameters

Click here to link to the approved procedures for Total Residual Chlorine, pH, Dissolved Oxygen, Specific Conductance, Termperature and Settleable Residue.

DWQ Director Approval Letters for Additional Certifiable Parameters 

Approval to certify for Acidity, Ignitability, Paint Filter Liquids, Boron, Potassium, Sodium and Total Organic Halides (TOX) 10/28/2002
Approval to certify for Strontium, Titanium, Lithium, Silica, CBOD, DOC, VSS, E. coli and Enterococci 03/02/2007
Approval to certify for Volatile Solids and Salinity 10/05/2007
Letter removing approval of Chlorophyll a by HPLC 10/11/2007
Approval to certify for Free Available Chlorine 09/27/2012
Approval to certify for Bromide 10/11/2012
Approval to certify for Clostridium perfringens and Coliphage  

 

DWQ Point Source Branch Letters

Total Residual Chlorine instrument sensitivity must detect below NPDES discharge permit requirements 08/14/2001
Total Residual Chlorine Compliance Limit is 50 µg/L 05/01/2008

 

EPA Approval Letters

US EPA Letter of approval for additional Metals not included in 40 CFR Part 136.3, Table IB - Methods 200.7 and 200.8 11/07/2007
US EPA approval letter to Regional Administrators for use of Luminescence Dissolved Oxygen (LDO) technology for DO and BOD analysis of wastewater - ASTM D888-05 01/03/2006
US EPA Region 4 approval letter for use of LDO technology for DO and BOD analysis of wastewater - ASTM D888-05 06/01/2006
US EPA approval letter for use of Luminescence Dissolved Oxygen (LDO)  technology for DO and BOD analysis of wastewater - Hach 10360 07/26/2006
US EPA Region 4 approval letter for use of LDO technology for DO and BOD analysis of wastewater - Hach 10360 07/01/2007
US EPA letter regarding allowable modifications to EPA Method 1664 A - HEM: Oil and Grease 01/16/2009
US EPA letters regarding ATP review of Colilert®-18 for Fecal Coliform analysis 07/28/2010
US EPA Region 4 Colilert®-18 ATP approval requirements for the Detection and Enumeration of Fecal Coliforms in Wastewater Samples (Instructions for obtaining certification for fecal coliform by Colilert-18® can be found here.)
10/01/2010
US EPA Letter regarding ATP approval of NCASI Method 71.01, "An Update of Procedures for the Measurement of Color in Pulp Mill Wastewaters", May 2000 11/08/2001
US EPA Letter regarding ATP approval of Hach Company Method 10206 - Spectrophotometric Measurement of Nitrate in Water and Wastewater 01/31/2013
US EPA Letter regarding ATP approval of Hach Company Method 10242 - Simplified Spectrophotometric Measurement of Total Kjeldahl Nitrogen in Water and Wastewater 01/31/2013

 

Division of Waste Management - UST and Solid Waste Section Guidelines

Link to UST Update on the January, 1998 MADEP Method, effective 02/01/2006, to the May, 2004 Revision 1.1 12/07/2005
UST Section request to certify commercial laboratories for EPA SW-846 method 8015B for Total Petroleum Hydrocarbons 03/26/2003
Memorandum regarding changes in UST guidelines 11/25/2008
Guidelines for Site Check, Tank Closure and Initial Response and Abatement for UST Releases - revision 1 11/26/2008
Guidelines for Assessment and Corrective Action for UST Releases 11/26/2008
Guidelines for Sampling - UST [Summary of Appendix B changes 05/01/2012] 05/01/2012
Solid Waste Section Memorandum regarding THF monitoring at Construction and Demolition Landfills 06/25/2010

 

Aquifer Protection Section 

APS Policy for Metals determination required by 15A NCAC 2L - SM 3030C is no longer required. 04/13/2013

 

Animal Waste Testing

MOA for Animal Waste Testing - coming soon06/14/2013
  
  

 

Additional Links

Information on the Methods Update Rule (MUR)

Information on the use of Discrete Analyzers

Information on SW-846 Updates IVA and IVB

Information on Horizon EPA Method 1664 A Compliance Options

 

 

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