United States
Environmental Protection
Agency
Labcert Bulletin
In This Issue...
This issue of the Labcert Bulletin addresses
issues which have been brought to our
attention by laboratories, and Regional and
State Certification Officers. You will find articles
on the National Environmental Methods Index
(NEMI), recent legislation, Stagel Disinfectants
and Disinfection Byproducts Rule, chlorite,
cyanide, and other drinking water issues.
If there are certification topics you would like to
see discussed, please call,,write, fax or e-mail the
editors. There is a form on page 6 for you to use
to add your name to our mailing list or to update
your information.
Editors:
EdGlick 513-569-7939
glick.ed@epa.gov
Patricia Hurr 513-569-7678
hurr.pat@epa.gov
Caroline Madding 513-569-7402
madding.caroline@epa.gov
MAILING ADDRESS:
USEPA MS 140
Technical Support Center ;
26 W. Martin Luther King Dr.
Cincinnati, OH 45268 .
FAXNumben 513-569-7191
Contact for
USEPA Laboratory ID
Numbers
Every laboratory wishing to be certified to
analyze compliance monitoring drinking water
samples must have a unique laboratory ID
Number. Laboratories must include this number
when reporting proficiency testing (PT) results.
Charles Feldmann, Office of Ground Water and
Drinking Water, Technical Support Center, is
the primary contact for assignment of new
laboratory IDs. He may be reached at 513-569-
7671 or FAX: 513-569-7191.
If the laboratory has ever participated in a
USEPA-run PT study, the laboratory will already
have a unique ID number. Please review any
previous "study results" report to locate the ID
number. If a laboratory cannot locate this
information, the laboratory should contact
Mr. Feldmann for assistance.
Reminder:
Drinking water regulations require laboratories to
demonstrate proficiency by successful analysis of
aPT sample each year for contaminants using the
same analytical method that is used to report
compliance monitoring results.
Website
An electronic version of this publication and much more can be found on the Office of Ground Water
and Drinking Water web page at http://www.epa.gov/OGWDW/standards.html. This site has
information about drinking water regulations and laboratory certification. The "Manual for the
Certification of Laboratories Analyzing Drinking Water," and past issues of the Labcert Bulletin can also
be found at this address.
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N
National Environmental Methods Index (NEMI)
Herb Brass
Office of Ground Water and Drinking Water, Technical Support Center
I EMI is an Oracle database of environmental method summaries for use in regulatory and non-
regulatory water quality analyses. The database may be searched from anywhere in the world, free
of charge, using the Internet at www.nemi.gov.
provided to the appropriate website, so that the
method can be purchased or otherwise obtained.
With NEMI, you can compare methods at a
glance and find the method that best meets your
needs. NEMI also supports sharing of monitoring
data among different agencies and projects, which
may use different methods at different times. The
Advisory Committee on Water Information
(ACWI), the senior advisory committee in the
federal government that deals with water
information, has "endorsed the continued
development and timely delivery of NEMI as a
vital tool to enhance the generation of comparable
data of known quality, across all entities that
conduct water quality monitoring." A letter
announcing the public release of NEMI was
recently co-signed by Diane Regas, then EPA
Deputy Assistant Administrator for Water, and
Bob Hirsch, US Geological Survey Associate
Director for Water. The letter can be accessed at:
http://water.usgs.gov/wicp/whatsnew.html.
NEMI has been developed under the guidance of
the Methods and Data Comparability Board
(MDCB). EPA and USGS co-chair the MDCB,
which includes representatives from the federal,
state/tribal, and private sectors. The MDCB and
its parent organization, the National Water Quality
Monitoring Council are committees under ACWI.
Currently, NEMI contains information on more
than 600 chemical, microbiological, and
radiological water methods that are used for
compliance and other purposes. Regulatory
information, that includes citations in the Federal
Register, are available for drinking water and
wastewater methods. For each method, NEMI
provides a summary of the procedure and
performance data. Quick method comparisons are
arranged in tables, with supporting details in text.
Links are provided to full methods available on
line or, when the methods are proprietary, a link is
The NEMI database was constructed using a state-
of-the-art Oracle platform so that it could
accommodate a broad range of method types that
require different data fields and search parameters.
The following classes of methods are currently
being or will soon be added — additional
chemical, microbiological, and radiological
methods; biological and field methods; methods
related to water security; and methods used in
matrices other than water. A strategic plan is
being developed to accommodate the addition of
these methods consistent with expressed
priorities, anticipated resources, and time.
Rule to Update Drinking Water and
Wastewater Methods
On October 23, 2002, a final "methods update"
rule was published in the Federal Register (Vol.
67, No. 205, pp 65220-65253). This rule approves
updated versions of chemical, microbiological,
and radiological analytical methods developed by
ASTM, Standard Methods, the US Geological
Survey, and the Department of Energy. No EPA
methods were approved. The methods apply to
the Safe Drinking Water Act and the Clean Water
Act compliance monitoring programs.
A Fact Sheet and the Final Rule are available at
http://www.epa.gov/ogwdw/regs.html and
http://www.epa.gov/waterscience/methods/.
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Additional Methods Approval
On October 29,2002, a final rule was published in
the Federal Register (Vol. 67, No. 209, pgs
65888-65902) that approves EPA Method 515.4
to support previously required NPDWR
compliance monitoring for 2,4-D, 2,4,5-TP,
dinoseb, pentachlorophenol, picloram • and
dalapon. In addition, EPA Method 531.2 is
approved for carbofuran and oxamyl. Additional
methods approved in this Federal Register include
a method for the determination of atrazine, two
methods for the determination of cyanide, two
methods for the determination of total coliforms
and E. coli, a method for the determination of
heterotrophic bacteria, and a method for the
determination of turbidity. More information can
be found at http://www.epa.gov/ogwdw/regs.html.
Chlorite Monitoring
Requirements under the
Stage 1 DBPR
The Stage 1 Disinfectants/Disinfection
Byproducts Rule requires two types of
chlorite monitoring for systems that! use
chlorine dioxide in their treatment process: daily
monitoring at the entry point to the distribution
system and monthly monitoring at three points in
the distribution system.
Daily chlorite monitoring:
The water entering the distribution system must be
analyzed daily for chlorite using one of three
approved analytical methods. Standard Method
4500-C1O2 E is an amperometric method; for
determining both chlorite and chlorine dioxide.
EPA Method 300.0 and EPA Method 300.1 are
both ion chromatographic methods. It is
anticipated that most of the daily analyses will
be performed by treatment plant personnel using
SM 4500-C1O2 E. The rule states that the analyses
must be performed by a party approved by the
State. This is the same type of approval that is
required to measure disinfectant residuals such as
chlorine dioxide or chlorine.
Distribution system chlorite monitoring:
In order to demonstrate compliance with the
chlorite maximum contaminant level (MCL),
water systems using chlorine dioxide must collect
a set of three samples in the distribution system on
a monthly basis. One sample is collected near the
first customer, one at a location representative of
average residence time, and the third at a location
reflecting maximum residence time in the
distribution system. The samples must be
analyzed using either EPA Method 300.0 or EPA
Method 300.1 and the laboratory must be certified
to perform the analysis.
Compliance with the chlorite MCL of 1.0 mg/L is
based on the arithmetic average of each 3-sample
set from the distribution system. If any daily
sample at the entry point indicates a chlorite
concentration greater than the MCL, then the
water system must collect a set of distribution
system samples on the following day. If none of
the daily samples have chlorite concentrations
greater than the MCL, then the distribution system
sampling is only required once each month. A
chlorite compliance determination is made for
each 3-sample set.
Stage 1 DBF Rule
The Stage 1 Disinfection By-Product (DBF) Rule
which was promulgated in December 1998
became effective for large surface water systems
in January 2002. These utilities were required to
begin monitoring for additional DBFs at that time.
All large surface water systems must monitor for
five haloacetic acids with the summation of their
concentrations to be reported as HAAS (similar to
the concept used for total trihalomethanes).
Utilities that use chlorine dioxide must monitor
for chlorite and systems using ozone must monitor
for bromate. This means that laboratories need
to be certified to analyze for HAAS, chlorite
and bromate.
The DBF Rule also requires that water systems
monitor for TOC. The regulation requires the
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TOC analyses be performed by a party approved
by the State. Please contact your states to
ascertain they are approving laboratories for TOC.
Methods 300.0 and 300.1
Differences and
Similarities
Dan Hautman
Office of Ground Water and Drinking Water,
Technical Support Center
In response to compliance inquiries about the
appropriate use of EPA Method 300.0 and EPA
Method 300.1, this article has been prepared to
clarify the differences and similarities, as well as
to relate the significance of these differences to
both laboratory certification and the classification
of these methods as approved for compliance
monitoring. Both of these methods employ ion
chromatography (1C) with suppressed
conductivity detection, hence, when considering
the determinative step, they are identical. The
only real differences between these two
procedures are the specified analytical columns, •
with their respective eluents, and for Part B, the
"on column" injection volume.
Method 300.1 was written primarily to identify
specific parameters (column, eluent and injection
volume) which could be employed to allow the
quantitation of lower concentrations of bromate in
drinking water. While doing this primarily for
bromate, it was decided that it would be best to
include all the 300.0 analytes into 300.1.
Additionally, we could simplify the method by
specifying a single analytical column for both
Parts A and B, and include some additional QC
such as a surrogate analyte.
EPA Method 300.0 is the general purpose 1C
method approved for compliance monitoring of
fluoride, nitrate, nitrite, chloride, sulfate, and o-
phosphate as well as chlorite at water systems
employing chlorine dioxide disinfection.
By closely examining Method 300.0, Section 2.4,
regarding method modifications and Sections
6.2.2.1 and 6.2.2.2 regarding optional analytical
columns, it becomes clear that Method 300.1
completely overlaps into Method 300.0. A
laboratory can adopt the parameters, columns and
specifications identified in 300.1, apply and pass
all the required QC that is shown in Section 9 of
300.0, and legitimately claim for certification or
approved method classification that they are using
Method 300.0, modified as permitted in the above
referenced sections. The reverse can not be said
about applying the operating conditions found in
Method 300.0 to Method 300.1. Comparable low
level measurements of bromate are not possible
using the Method 300.0 standard operating
conditions.
If you have additional questions do not hesitate to
contact Dan Hautman at 513-569-7274 or E-mail
at Hautman.Dan@epa.gov.
Another Website
They make it easier all the time. At
http://www.epa.gov/fedreg/subscribe.htm you can
subscribe to have the daily Federal Register
delivered to your email box. You may suscribe to
any or all of the 12 categories, one of which is
"Water." And if your mailbox gets too full, you
can unsubscribe at any time.
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W
Cyanide Clarification
•e were recently asked for clarification about the cyanide methods, specifically, what methods are
approved for analysis of cyanide in drinking water and whether or not distillation is required.
The 1994 Technical Notes (EPA600/R-94/173, October 1994) emphasizes that spectrophotometric
measurements for cyanide in water always require a manual distillation of the sample to prepare the sample
for measurement. EPA felt the Technical Note was needed because some laboratories seemed to be
unaware of the requirement to distill samples. Although free cyanide is regulated, the approved
spectrophotometric methods are for total and amenable cyanide; therefore, distillation is required. The
"total" cyanide methods are used to screen samples for cyanide. If the "total" cyanide level is greater than
the MCL (0.2 mg/L), then analysis for "free" (amenable) cyanide must be performed to see if the MCL has
been exceeded. The "total" cyanide analysis is still recommended because it is cheaper than the amenable
test.
!
All approved methods for cyanide are listed at 40 CFR 141.23(k)(l). The mandatory manual distillation
procedure is described in Standard Method SM-4500-CN-C and ASTM D2036-91. The approved
amenable, manual and automated spectrophotometric methods are shown in the table below.
Technology (use only after distillation)
Manual Spectrophotometric, Amenable
Manual Spectrophotometric, Total
Semi-automated Spectrophotometric, Total
EPA
335.4
ASTM
D2036-91B
D2036-91A
SM
4500-CN-G
4500-CN-E
USGS
1-3300-85
Free cyanide can also be determined by one method approved for drinking water compliance monitoring
analysis that does not require distillation, the specific ion electrode method, SM-4500-CN-F. When using
this method, it is mandatory to maintain a constant ionic strength background for the electrode measurement,
that is, samples and standards must contain the same concentration of sodium hydroxide. More information
concerning methods can be found in FRN Vol 57, No 138, Friday, July 1992, p 31800.
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Sparging Chlorite Samples
The ion chromatographic methods for chlorite recommend that the sample be sparged in order to
remove any residual chlorine dioxide that may be present in the sample. This is because chlorite is
formed from chlorine dioxide. Thus, chlorine dioxide will cause a positive bias in the analytical result
if it isn't removed at the time of sample collection.
Most water systems do not use chlorine dioxide as
a residual disinfectant, so usually the water
leaving the treatment plant does not contain a
significant chlorine dioxide residual. If this is the
case, the water system does not need to worry
about the sparging step. In fact, sparging chlorite
compliance samples is only recommended when
chlorine dioxide is present at a high enough
concentration that if it completely converted to
chlorite, it would result in a chlorite concentration
near the maximum contaminant level (MCL) of
1.0 mg/L. Since the chlorine dioxide
concentration is monitored daily at the entry point
to the distribution system, water systems should
know whether there is a potential for significant
chlorine dioxide residuals at the chlorite sampling
points.
If it is determined that chlorine dioxide poses a
potential problem in chlorite compliance
monitoring samples, then the sampler should
sparge the samples at the time of collection. Since
chlorine dioxide is volatile, it is not hard to
remove it. The sample should be collected in a
clean, wide-mouth container (such as a beaker or
Erlenmeyer flask). The sparging gas can be
obtained by using a lecture bottle of nitrogen or
helium fitted with a regulator and connected to a
disposable glass Pasteur pipette with P VC tubing.
The gas flow should be adjusted to produce a
steady flow of bubbles. After .10-15 minutes of
sparging, all traces of chlorine dioxide should be
removed from the sample. It can then be poured
from the container into the sample bottle that
contains the ethylenediamine (EDA) preservative.
In order to eliminate potential cross-
contamination problems, it is recommended that
a clean container and a new disposable pipette be
used at each sampling point.
A blank should be prepared and analyzed for
chlorite prior to the first field use of the sparging
apparatus. Reagent water should be sparged for
15 minutes and then poured into a sample bottle
that contains the EDA preservative. This blank
sample should be analyzed for chlorite in order to
ensure that contaminants are not introduced into
the sample from the sparging gas or the PVC
tubing which would interfere with the chlorite
analysis. Periodic preparation and analysis of
sparged blanks is recommended to demonstrate
that the sparging procedure does not introduce
interferences.
Fax It To Us
Please add/change (circle one) my name to the
Labcert Bulletin mailing list.
Name:
Company:,
Address:
Telephone:,
Fax#: "
Fax to:
Susan Hagedorn
USEPA - TSC
26 W. M.L. King Drive
Cincinnati,. OH 45268
513-569-7191
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MICRO PT Q & A
The following are some questions we have
received concerning evaluation of Micro PTs.
In the discussion:
Positive = Present Negative = Absent
1. False Positives: Is it permissible to report a
false positive result on both a total coliform.
analyte and a fecal coliform/E. coli analyte in the
same or separate samples within the PT set and be
considered "acceptable" for the study?
Yes. One sample (vial) may be missed per
analyte. However, a lab cannot report an
"Absent" for a Total Coliform and a "Present"
for Fecal/E. Coli for the same sample (vial) and
have that false positive be considered
"acceptable." If a lab reports "absent" for
Total Coliform, the test ends.
i
2. False Negatives: Does one false negative
reported value result in a "not acceptable" for the
PT study, even though a lab could still pass nine
out often samples within the set for one analyte
but not the other?
Yes. This means the lab missed a positive
sample which is a public health concern.
3. Analyte Definition: It is my understanding that
Total Coliform is considered one analyte and
Fecal Coliform/fi'. Coli. is considered one analyte.
That is correct.
4. "Acceptable " analysis of a sample: Each PT
study consists often samples. If a lab misses one
analyte within the sample, is the sample
considered "not acceptable"?
Any false negative or more than one false
positive per analyte would be considered "not
acceptable". Otherwise same as answer No. 1.
And......More Websites
Other websights that you may find useful are:
www.epa.gov/ogwdw/regs.html lists drinking water
regulations;
www.epa.gov/ogwdw/methods/methods.html lists all
promulgated methods and contains copies of some
methods;
www.epa.gov/safewater/faq/sco.htm lists state
certification contacts for every state and also gives
links to lists of state laboratories certified for drinking
water analyses. There are links for those states,
which have electronic lists of their certified
laboratories;
www.epa.gov/ttn/nelac/ contains the NELAC
Standards, lists NELAC Accrediting Authorities and
accredited laboratories, and has information about past
and future NELAC meetings;
www.ts.nist.gov/ts/h.tdocs/210/214/scopes/programs.
html lists NIST-accredited PT providers;
www.epa. gov/qualitv/ contains all EPA Quality
Documents and requirements, as well as available QA
training and information about the annual EPA QA
meeting.
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vvEPA
United States
Environmental Protection
Agoncy
OfSce of Ground Water and Drinking Water
Cincinnati, OH 45268
EPA815-N-03-001
March 2003
In This Issue..!
S NEMI - t ft , . , „,
«/ Recent promulgation of drinking /
water methods " <-„ <• '; - " - * '*--_,
S Chlorite sampling and, monitoring ;
; requirements outlined ^ '-^ '^''-> f/
V Cyanide methods clarified \.,(> ~ rj, ~-
S EPA Method 30
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