Non-Field Guidance and Technical Assistance
The information contained on these pages is meant to provide technical assistance and guidance for meeting the requirements of NC WW/GW Laboratory Certification. On this page you will find guidance documents and technical assistance as well as Approved Procedures for Field Parameters. The following pages contain policies and checklists pertaining to laboratory operations.
Guidance and Technical Assistance Materials
Guidance documents are meant to provide detailed information for meeting policy or regulatory requirements.
| Document | Description |
|---|---|
| Fecal Sludge MPN Determination Guidance | How to determine the appropriate dilutions when referencing SM 9221 C E-2006 |
| 1631 LL Hg Preservation Clarification | Letter from EPA Region 4 clarifying the preservation and hold time requirements found in EPA 1631, Rev. E and 40 CFR 136.3 Table II Footnote 17. |
| Memo from NC WW/GW LC on 1631 | Memo released in 2004 by the Certification Branch with further interpretation on the letter from EPA Region 4 |
| MDL Presentation | Lab Tech Day 2018 presentation about the new MDL procedure. |
| Fecal Coliform (MF) Colony Confirmation Video | This video provides a visual example of most elements involved in performing the monthly fecal coliform colony verification required for laboratories certified for Standard Methods 9222D. Please use this in conjunction with the technical assistance document linked below to assure all requirements are met and to further explain the process. |
| Fecal MF Colony Verification Technical Assistance | Assistance in performing the required monthly colony verification for Fecal Coliform (Membrane Filter) |
| Fecal MF Colony Verification Example Benchsheet | Example benchsheet to use when performing the colony verification and adjusting colony counts |
| Fecal Coliform Reporting Guidelines | Guidelines for enumerating and reporting fecal coliform results |
| MPN Table with 95% Confidence Ranges | Table provided by IDEXX with MPN results and 95% confidence ranges using the Quanti-Tray/2000 which can be used to evaluate duplicate precision. |
| LDO Daily Calibration Verification Procedure | A procedure for verifying the calibration of Luminescence Dissolved Oxygen (LDO) meters by back calculation with solubility table |
| Calibration of Pipettors | An example procedure for the gravimetric verification of mechanical liquid dispensing devices |
| Matrix Spiking Technical Assistance Document | A document describing appropriate matrix spiking frequencies and practices |
| Memo to Permittees Regarding TRC 50 µg/L Compliance Level | A memo from the NC DWQ Point Source Branch describing the 50 ppb compliance level for Total Residual Chlorine (TRC) |
| Corrective Action Response to Audit Findings Guidance | A document describing the corrective action response and documentation needed for labs to address Findings from audits. |
| Corrective Action Response (CAR) for PT example | This document provides guidance on root cause analysis and corrective action response and includes an example of a CAR form (this form is not required). |
| Ammonia/Fluoride Distillation Technical Assistance Document | A document describing the background and implementation of Ammonia and Fluoride distillation study requirements in accordance with 40 CFR Part 136.3, Table IB, footnote 6. Revised 10/9/2024 |
| Ammonia/Fluoride Distillation Flow Chart | A flow chart showing how to set up the distillation study (see Tools table below for a calculation spreadsheet) |
Tools
This table provides computer applications, spreadsheets, calculators, etc. to aid laboratories and laboratory analysts in meeting certification and quality assurance requirements.
| Tool | Description |
|---|---|
| MDL Calculator for single analyte parameters | Spreadsheet used to calculate initial and on-going MDL for single analyte parameters |
| MDL Calculator for multi-analyte parameters | Spreadsheet used to calculate initial and on-going MDL for multi-analyte parameters |
| Ammonia/Fluoride Distillation calculation spreadsheet | A spreadsheet that can be used to evaluate the distillation study results |
| 5-pt Spectrophotometric Curve Evaluation Spreadsheet | This spreadsheet is used to evaluate 5-standard spectrophotometric curves and back-calculate standards. (not for verifying factory set curves) |
| 6-pt (Total Phos) Spec Curve Evaluation Spreadsheet | This spreadsheet is used to evaluate 6-standard spectrophotometric curves (required by many phosphorous methods)and back-calculate standards. (not for verifying factory set curves) |
Total Residual Chorine (TRC) Curve Verification Calculators | Excel® spreadsheets for calculating the correlation coefficient and percent recoveries of standards used to verify the factory-set instrument calibration. The worksheets may also be used to document the process and satisfy record retention requirements. |
TRC User-Generated Curve Calculator | An Excel® spreadsheet for calculating the correlation coefficient and percent recoveries of standards used for instrument calibration with a user-generated curve. The worksheet may also be used to document the process and satisfy record retention requirements. |
| Adjustable Pipettor Calibration Worksheet | An Excel® spreadsheet for determining relative error and coefficient of variation of adjustable pipettors. An example procedure for calibrating mechanical volumetric liquid-dispensing devices can be viewed here. |
| Fixed Pipettor Calibration Worksheet | An Excel® spreadsheet for determining relative error and coefficient of variation of fixed pipettors. An example procedure for calibrating mechanical volumetric liquid-dispensing devices can be viewed here. |
| ADMI Color Calculation Spreadsheet | An Excel® spreadsheet for calculating ADMI color using the Tristimulus Filter Method. Tristimulus values are converted to an ADMI single number color difference of all the same magnitude assigned to PtCo standards using the Adams Nickerson Color Difference (DE). |
| Total Hardness (mg/L as CaCO3) Calculator | An Excel® spreadsheet for calculating Total Hardness (mg/L as CaCO3) using results obtained for Calcium and Magnesium. |
| SOUR Calculation and Temperature Correction for pH | Link to Land Application Unit's VAR Option 4 spreadsheets |
Approved Procedures for the Analysis of Field Parameters
These documents are intended to provide the approved procedures and requirements for measurement of Field parameters. You may refer to the approved method reference, instrument manufacturer's manual or other resources for additional information. They can be downloaded from the Field lab procedures and technical assistance page of this website.
Link to National Pollution Discharge Elimination System (NPDES) Permitting Guidance, Directions for Completing a Discharge Monitoring Report (DMR) and Calculating Data for DMR reporting. Look under Compliance Forms. You can also find a link to the list of Significant Figures and Their Use on DMRs document and DMR parameter code descriptions on that page. [NOTE: The parameter code for any Fecal coliform regardless of technology (e.g., Colilert-18, MF, MPN/100 mL, etc.) code is now 31616]
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This page was last modified on 10/09/2024