April 21, 2000

To:       Water Resources Division

From:     Peter F. Rogerson, Senior Chemist Office of Water Quality

For:      LeRoy Schroder, Chief Branch of Quality Systems

Subject:  Approval of a Water Quality Analytical Method for Processing, 
          Taxonomy, and Quality Control of Benthic Macroinvertebrate 
          Samples

The Office of Water Quality has approved a water-quality analytical method 
by the National Water Quality laboratory (NWQL) for processing, taxonomy, 
and quality control of benthic macroinvertebrate samples.  This 
water-quality analytical methods approval follows the technical procedure 
specified in OWQ Tech Memo 98.05.  The draft OFR, which will be submitted 
for Director's approval, is entitled: 
"Methods of Analysis by the U.S. Geological Survey National Water Quality 
laboratory? Processing, Taxonomy, and Quality Control of Benthic 
Macroinvertebrate Samples" by Stephen R. Moulton II, James L. Carter, 
Scott A. Grotheer, Thomas F. Cuffney, and Terry M. Short. 

This OFR describes U.S. Geological Survey (USGS) method B-9135-00.  The 
fixed-count quantitative portion of this method is similar to the U.S. 
Environmental Protection Agency (USEPA) rapid bioassessment protocol (RBP) 
(Barbour, et.al., USEPA Report 841-B-99-002, and Plafkin, et.al., USEPA 
Report 444/4-89-001.)  The method describes sample processing, qualitative 
species identification, and quantitative species identification and 
enumeration.  It includes quality assurance and quality control procedures 
that ensure comparable data.  Estimates of precision, based upon 
sub-sampling procedures, are provided.  Different levels of identification 
are also provided for many taxa.  Because of current data system limitations, 
only limited information is available from the NWQL on-line catalog at:  
wwwnwql.cr.usgs.gov/USGS/USGS_gen.html .  For more detailed information 
prior to release of this OFR, please contact Steve Moulton at the NWQL 
smoulto@usgs.gov  (303) 236-3493.)  If you have questions or need more 
information about the methods approval process, please contact Pete Rogerson 
rogerson@usgs.gov , (303) 236-1836.