Preferred Parameter Codes for Indicator Bacteria Methods

In Reply Refer To:
Mail Stop 412                                           February 23, 2001

Office of Water Quality Technical Memorandum 2001.05

Subject:  Preferred Parameter Codes for Indicator Bacteria Methods

The large number of parameter codes established over the years for storing
microbiological determinations in STORET and NWIS has led to some confusion
as to which is the most appropriate code to use with each method.  This
confusion is due primarily to incomplete or misleading descriptions listed
with the codes and duplication where two codes represent the same method.

The purpose of this memo is to communicate some newly updated descriptions
for some indicator bacteria parameter codes and indicate which of these
codes is preferred for the Water Resources Division.  New descriptions were
established to better represent the analysis and to obtain a consistent
format.  The old parameter description for all codes that have been updated
is listed in brackets for reference. The codes listed first under each
category indicate the preferred methods for water analysis and are the ones
listed on the newly revised ground and surface water-quality field forms.
Additional codes listed are for similar but not preferred methods, for
proprietary methods (Colilert), or for methods testing sediments.

Projects may have bacteria data stored in NWIS under parameter codes
different from the ones listed as preferred in this memorandum.  Historical
data do not need to be changed but all new data as of March 1, 2001, should
follow guidance from this memorandum.  Districts should, at their
discretion, update any data that may have been stored erroneously due to
confusion with the older misleading parameter descriptions.

Questions about the information in this memorandum should be directed to
Donna Francy (dsfrancy) in the Ohio District or Stephen Sorenson (sorenson)
in the Office of Water Quality.

TOTAL COLIFORM:

31501, Total coliform, mENDO MF method, water, colonies/100 ml [coliform,
membrane filter immediate mENDO medium (colonies/100 ml)]?This parameter
code is the proper code for the membrane filter, mENDO agar method (Britton
and Greeson, 1987, p. 13-16).

31504, coliform total immed. mem. fil (col./100mL) ?This parameter code
description has the method missing and is not recommended for use with any
new data.

50569, Total coliform, Colilert Quantitray method, water, mpn/100 ml [total
coliform, ONPG-MUG, autoanalysis, Colilert system, water, unfiltered, most
probable number per 100 milliliters]--This is the Colilert Quantitray
method (Idexx Laboratories, Westbrook, Maine).  Code 90908 is a temporary
code for this same analysis but should not be used with any new data.

90900, Total coliform, MI MF method, water, colonies/100 ml [total
coliform, water, unfiltered, MF, MI agar, 35 degrees Celsius, colonies per
100 milliliters]?This is the MI agar method and allows the simultaneous
enumeration of total coliforms and Escherichia coli (U.S. Environmental
Protection Agency, 2000a).  It is recommended for use in analyzing
ground-water samples.

FECAL COLIFORM:

31625, Fecal coliform, mFC MF method, water, colonies/100 ml [Fecal
coliform, .7 um-MF (col./100 mL)]?This is the mFC agar method (Britton and
Greeson, 1987, p. 37-40). Parameter code 31625 was established when the 0.7
micron filter was recommended for the mFC method.

31616, Coliform, fecal, membrane filter m-FC media at 44.5 deg. C
(colonies/100 ml)?This is the mFC agar method and is identical to parameter
code 31625 except that it uses a 0.45 micron filter. The use of the 0.45
micron filter is not recommended for fecal coliform analysis but this
parameter code was used extensively in the past.

50469, Fecal coliform, mFC MF method, sediment/bed material, colonies/gm
(dry weight) [fecal coliform, sediment, bed material, MFC agar, 44.5 deg C,
24 hr, dry weight, col/gm]?This is the mFC agar method for sediment.

ESCHERICHIA COLI (E. COLI):

31633, E. coli, mTEC MF method, water, colonies/100 ml [E. coli, water,
whole, total, thermotol, MF, m-TEC, in-situ, urease, (col/100ml)]?This is
the mTEC agar method (U.S. Environmental Protection Agency, 1986 and 2000b)
for water and is widely used for monitoring recreational and ambient
surface waters.

50278, E. coli, NA-MUG MF medium, water, colonies/100 ml [E. coli, water,
filtered, MF, 0.7 u, Nutrient agar + MUG, 4 hours, 35 degrees C,
colonies]?This is the NA-MUG method for water (U.S. Environmental
Protection Agency, 1991), to be used as a secondary incubation with mENDO
medium (code 31501) for total coliform. This method is recommended for use
in analyzing ground-water samples.

50466, E. coli, mTEC MF method, sediment/bed material, colonies/gm (dry
weight) [E. coli, MF, m-TEC agar, urease, bed material, dry weight,
colonies/gram]? This is the mTEC agar method for sediment.

50467, E. coli, Colilert Quantitray method, sediment/bed material, mpn/gm
(dry weight) [E. coli, ONPG-MUG, auto analysis, Colilert system, bed
material, dry weight, colonies/gram]--This is the Colilert Quantitray
method for sediment.

50468, E. coli, Colilert Quantitray method, water, mpn/100 ml [E. coli,
ONPG-MUG, auto analysis, Colilert system, water, unfiltered, colonies/100]
--This is the Colilert Quantitray method for water.

90901, E. coli, MI MF agar, water, colonies/100 ml [E. coli, water,
unfiltered, MF, MI agar, 35 degrees Celsius, colonies per 100 milliliters]
--This is the MI agar method (U.S. Environmental Protection Agency, 2000a)
for E. coli in water.

90902, E. coli, modified mTEC MF method, water, colonies/100 ml [E. coli,
water, unfiltered, MF, modified m-Tec agar, colonies per 100 milliliters]
--This is the modified mTEC method for water method (U.S. Environmental
Protection Agency, 2000b) and is a one-step alternative to the standard
mTEC method (31633) for monitoring recreational and ambient surface waters.

FECAL STREPTOCOCCI:

31673, Fecal Streptococci, KF streptococcus MF method, water, colonies/100
ml [Streptococci, fecal, membrane filter, KF agar (colonies/100 ml)]?This
is the KF streptococcus agar method for water (Britton and Greeson, 1987,
p. 47-50).

ENTEROCOCCI:

31649, Enterococci, mE MF method, water, colonies/100 ml [Entercocci, mE,
membrane filter, water, whole, total (colonies/100 ml)]?This is a 48-hour,
two-step test for enterococci using the mE agar method (U.S. Environmental
Protection Agency, 1986).

90909, Enterococci, mEI MF method, water, colonies/100 ml [Enterococci,
mEI, biota, water, filtered, membrane filter, 24-hour incubation, onestep
method, colonies per 100 ml]?This is the 24-hour, one-step test for
enterococci using mEI agar (U. S. Environmental Protection Agency, 1997 and
2000b).

Either method for enterococci may be used with equal preference.

CLOSTRIDIUM PERFRINGENS:

90915, Clostridium perfringens, mCP MF method, water, colonies/100 ml [
Clostridium perfringens, MF, mCP agar, Amm. Hydrox., 44.5 deg C, water,
colonies/100 ml]?The mCP agar method (U.S. Environmental Protection Agency,
1996) is done in the laboratory.

REFERENCES:

Britton, L.J., and Greeson, P.E., eds., 1987, Methods for collection and
   analysis of aquatic biological and microbiological samples: U.S.
   Geological Survey Techniques of Water-Resources Investigations, book 5,
   chap. A4, variously paginated.

U.S. Environmental Protection Agency, 1986, Test method for Escherichia
   coli and enterococci in water by the membrane-filter procedure:
   Cincinnati, Ohio, EPA 600/4-85/076, 24 p.

U.S. Environmental Protection Agency, 1991, Test methods for Escherichia
   coli in drinking water?Test Method 1105: Cincinnati, EPA/600/4-91/016, 2
   p.

U.S. Environmental Protection Agency, 1996, EPA Information Collection Rule
   microbial laboratory manual: Washington, D.C., EPA/600/R-95/178, section
   XI.

U.S. Environmental Protection Agency, 1997, Method 1600?Membrane filter
   test method for enterococci in water: Washington, D.C.,
   EPA/821/R-97/004, May 1997.

U.S. Environmental Protection Agency, 2000a, Membrane filter method for the
   simultaneous detection of total coliforms and Escherichia coli in
   drinking water: Cincinnati, Ohio, EPA 600-R-00-013, 20 p.

U.S. Environmental Protection Agency, 2000b, Improved enumeration methods
   for the recreational water quality indicators: Enterococci and
   Escherichia coli: Washington, D.C., EPA/821/R-97/004, March 2000.

                          Janice R. Ward /s/
                          Acting Chief, Office of Quality

This memorandum does not supersede any other Office of Water Quality
Technical Memorandum.

Distribution:  All WRD Employees


(See attached file: tm0105_bacteria_param.doc)

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