Replacement of National Water Quality Laboratory Schedule 172, Determination of Trace Elements in Blank Water, with Schedule 1673

In Reply Refer to:
Mail Stop 412                                           May 9, 2001

Office of Water Quality Technical Memorandum 2001.06

Subject:  Replacement of National Water Quality Laboratory Schedule 172,
          Determination of Trace Elements in Blank Water, with Schedule
          1673

BACKGROUND

The "parts-per-billion" inorganic protocol documentation (Horowitz, 1994)
and 3 Office of Water Quality (OWQ) Technical Memoranda (94.06, 94.12, and
97.03) specifically mention National Water Quality Laboratory (NWQL)
Schedule 172 as the only schedule to use for inorganic trace element blank
determinations.  Effective June 1, 2001 (NWQL Technical Memorandum
2001.01), the NWQL is replacing Schedule 172 with Schedule 1673.  Schedule
1673 offers additional trace elements and uses reporting limits based upon
long-term method detection level (LT-MDL) procedures (Childress, 1999).  An
additional advantage with this change is that blanks and environmental
samples will be determined using identical analytical methodology, a plus
for some study objectives.

PURPOSE OF MEMORANDUM

This memorandum documents the replacement of Schedule 172 by Schedule 1673
in documentation related to the "parts-per-billion" inorganic protocol
(Horowitz, 1994 and the 3 OWQ memos mentioned above.)  Details about
Schedule 1673 are available in NWQL Technical Memorandum 2001.01 and from
SPiN on the NWQL web site: http://wwwnwql.cr.usgs.gov/USGS/USGS_gen.html.
The three OWQ memos and the NWQL memo are available at:
http://water.usgs.gov/admin/memo/index.html.

REFERENCES

Horowitz, A.J., Demas, C.R., Fitzgerald, K.K., Miller, T.L., and Rickert,
   D.A.  1994.  U.S. Geological Survey Protocol for the Collection and
   Processing of Surface-Water Samples for the Subsequent Determination of
   Inorganic Constituents in Filtered Water.  U.S. Geological Survey Open
   File Report 94-539.  57 p.

OWQ Technical Memorandum 94.06.  New Custom Analysis Schedule (172) for
   Blanks.

OWQ Technical Memorandum 94.12.  Change in Schedule 172.

OWQ Technical Memorandum 97.03.  Protocols for Cleaning a Teflon Cone
   Splitter to Produce Contaminant-Free Subsamples for Subsequent
   Determinations of Trace Elements.

NWQL Technical Memorandum 2001.01.  Elimination of National Water Quality
   Laboratory Blank Schedule 172.

Childress, C.J. Oblinger, Foreman, W.T., Connor, B.F., and Maloney, T.J.
   1999.  New Reporting Procedures Based on Long-Term Method Detection
   Levels and Some Considerations for Interpretation of Water-Quality Data
   Provided by the
U.S. Geological Survey National Water Quality Laboratory.  U.S. Geological
   Survey Open File Report 99-193.  19p.

CONTACTS

Kathy Fitzgerald, OWQ, (kkfitz@usgs.gov) can discuss the inorganic sample
collection protocol.

Mark Burkhardt, Chief, Analytical Services, NWQL, (mrburk@usgs.gov) can
describe Schedule 1673.


                         Janice R. Ward /signed/
                         Acting Chief, Office of Water Quality

This memorandum supersedes those parts of OWQ Technical Memoranda 94.06,
94.12, and 97.03 that refer to Schedule 172.

Distribution:  All WRD Employees

(See attached file: techmemo.nwql.01.06.doc)

Janice Ward
Acting Chief, Office of Water Quality
US Geological Survey
Reston, VA
703-648-6871
jward@usgs.go