TM98-07 Reporting Level Changes for Volatile Organic Compounds (Schedules 2020/2021), Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES), Ammonia plus Organic Nitrogen and Phosphorus (micro-Kjeldahl) in Water Methods at the National Water Q

This memorandum provides long-term method detection levels (LT–MDLs) and sets reporting levels at the nondetection value (NDV) for four water methods at the National Water Quality Laboratory (NWQL), effective on October 1, 1998: 

1. Low-level volatile organic compounds (VOCs) by gas chromatography/mass spectrometry (schedules 2020 and 2021),
2. Trace elements in filtered water by inductively coupled plasma–atomic emission spectrometry (ICP–AES),
3. Ammonia plus organic nitrogen (micro-Kjeldahl digestion), and 
4. Phosphorus (micro-Kjeldahl digestion). This memorandum also outlines new reporting conventions for these four methods. 

A forthcoming Office of Water Quality (OWQ) technical memorandum will describe the LT–MDL procedure for establishing detection and reporting levels, detail the new reporting conventions and the potential changes to the historic data record, and provide guidance on data interpretation using data reported with the new conventions. Distribution of this OWQ technical memorandum is planned for early FY99.