National Water-Quality Assessment (NAWQA) (public)
National Analysis of Trace Elements (public)
Trace Elements National Synthesis internal homepage - Archive of 'TE News'
To: nawqa 91pc, nawqa 94pc, nawqa 97pc, nawqa 01pc, wqspecs
Cc: nawqa nst, ahwelch, pcvanmet, rdeweese, dpkrabbe, sjryker, cory,
mkoterba, nawqa nlt, pahamilt, egraffy, akwill, crawford, william_brumbaugh
From: Dennis R Helsel
Date: 04/02/01 10:58 AM
Subject: TE sampling in the 01 Study Units
Several changes took place in NAWQA trace element work with the beginning of sampling in the 1997 study units, and more has now changed with the beginning of Cycle 2 of NAWQA. Current trace element activities for 2001 study units are summarized below, highlighting changes since the 1991 study units were active. This summary is consistent with the NIT Cycle 2 planning document and current as of today (4/02/01). Future alterations are possible due to changes in budget and/or Program objectives.
Particle-associated contaminants (PACs) will be measured within most study units by the Coring Project headed by Pete Van Metre. A full suite of metals, in addition to the other contaminants measured by the Project over the last 10 years, will be analyzed in cores taken from reservoirs and lakes. Study unit staffs work with Pete to locate sampling sites suitable for both the Project and study unit. At least one study-unit scientist is actively involved with Project staff during sampling and data analysis.
For new reference sites not sampled during Cycle I, one bed sediment sample is to be collected and sieved at 63 microns consistent with Cycle I study methods. Chemical analysis is performed through the NWQL using Schedule 2420. Data from these sites will be added to the information collected during Cycle I on occurrence and distribution of trace elements in stream sediments.
With the exception of new reference sites described above, no stream bed sediment samples need be collected and analyzed for trace elements.
Mercury in fish fillets, and total- and methyl-mercury in water and sediment, will be measured at 8 sites in every study unit. This occurrence sampling is separate from mercury work done in topical studies. Sites represent a gradient of wetlands and a gradient of atmospheric inputs of mercury across the study unit. This combination of gradients results in three general classes of sites:
Target species is a top predator freshwater fish available at every site. If at all possible, collect largemouth bass; otherwise, collect a predator species that is most common. Attempt to get all fish of a uniform length and 3 years in age.
Other parameters, including Acid Volatile Sulfide (AVS) in sediment, and DOC in water, will also be measured. Detailed instructions will be provided by Dave Krabbenhoft and Rod DeWeese.
No trace elements other than mercury need be measured in tissue samples. Fish fillets as described above are the target sampling media instead of fish livers, invertebrates, or other target taxa sampled during Cycle I.
In every study unit doing MAS and LUS work, trace elements will be measured using NWQL Schedule 2710 plus radon (LC1369) at every site in these basic NAWQA networks. This is true whether or not trace elements were measured at these sites during Cycle I. Radium species (Schedule 1263) will be measured in 10% of LIP samples.
Trace elements were not a required analysis for the 1991 study units, though many did them in their subunit surveys. Essentially all of the 1994 study units included trace elements in subunit surveys, and trace elements were required for the 1997 study units.
Trace elements (Schedule 2710 plus LC1369) will be measured in all LIP ground water samples. Radium species (Schedule 1263) will be measured in 10% of LIP samples.
For quarterly sampling during the HIP, a reduced trace element schedule may be employed, and/or samples may be analyzed for trace elements only twice per year (every other sample).
Trace elements were not a required analysis for LIP sampling prior to the 2001 studies. No quarterly or other within-year ground water sampling was required in Cycle I.
Visit the TE external page at: http://water.usgs.gov/nawqa/trace/ for up to date info on regulations, publications, etc.
The TE synthesis internal page has much info for study units:
http://water.usgs.gov/nawqa-only/trace/
including all the TE News. The previous four were:
v.13 Arsenic in Groundwater; new proposed MCL 5/30/00 v.14 Changes in radchem data reporting 9/29/00 v.15 New arsenic MCL at 10 ug/L 1/19/01 v.16 New methylmercury criteria 2/05/01
Trace Element National Synthesis internal homepage - Archive of 'TE News'
National Analysis of Trace Elements (public)
National Water-Quality Assessment (NAWQA) (public)
This page is http://water.usgs.gov/nawqa-only/trace/tenews/v17.html
Email comments/questions to traceweb@usgs.gov
Last modified: 02Apr2001