United States
[Environmental Protection
Agency
Office of Ground Water
and Drinking Water
Cincinnati, OH
EPA-814N 95001
August 1995
SEPA Labcert Bulletin
In This Issue
In September 1992, we published a table of the
regulated drinking water contaminants with
MCLs, methods, etc. In this issue you will find
an updated table, a brief update; on the ICR,
some frequently asked questions (with answers)
about the Methods Update Federal Register
Notice (MUFRN) and certification guidance for
PCBs. Of course, if there are any discrepancies
between the table and 40 CFR, the Code is
correct. As always, your questions and
comments are welcome.
The Editors:
Edward M. Click 513 569-7939
Mary Ann Feige 513 569-7944
Caroline Madding 513 569-7402
26 W. Martin Luther King Dr.
Cincinnati, OH 45268
ICR Lab Approval Update
The proposed Information Collection Rule
(ICR) was published in the Federal Register
on February 10, 1994 (59 FR 6332).
Promulgation is expected in December 1995 with
monitoring to begin in early 1996. Below is an
update of the lab approval process.
Lab Approval - Chemistry
As proposed, labs must register and apply for
approval, meet specific criteria for each method,
and pass one PE study to receive EPA approval.
Two PE studies have been conducted and a third
PE study is scheduled between promulgation and
the beginning of monitoring. Laboratories
registered with EPA were notified of the PE
studies. Revised sections of the ICR/DBP
Analytical Guidance Manual and application
packages were sent to registered labs in early
April 1995.
Lab Approval - Microbiology
Applications were sent to registered laboratories
during the past six months. The applications
returned to EPA are currently being reviewed.
After EPA review of the applications,
laboratories must satisfactorily analyze QC and
PE samples and pass an on-site evaluation. EPA
began PE studies for viruses in August and
expects to begin on-site evaluations and PE
studies for virus and protozoa laboratories in late
1995. Registered laboratories will be kept
informed of EPA's progress on microbiology
laboratory approval and will receive updated
methods and training materials when they are
available.
Laboratory Approval Requests
To be approved to analyze samples for the ICR,
laboratories should write to the following
address:
ICR Laboratory Coordinator
Technical Support Division
Office of Ground Water and
Drinking Water, USEPA
26 West Martin Luther King Dr.
Cincinnati, OH 45268
For current ICR updates, call the Safe Drinking
Water Hotline (800 426-4791)
or E-Mail them at their Internet address:
HOTLINE-SD WA@EP AM AIL. EP A. GOV.
Printed on Recycled Paper
-------
1994 Methods Rule
A final rule, Analytical Methods for Regulated
r\Drinking Water Contaminants (MUFRN),
was published on December 5, 1994 in the
Federal Register (59 FR 62456-71). Effective
January 4, 1995, twelve new analytical methods
were approved and many methods were updated
to the most recent version. On July 1, 1996, the
rule withdraws approval for 38 U.S. EPA, three
Standard Method and two ASTM methods. The
rule also contains mandatory method
modifications and optional procedures developed
after the approved methods were published.
These changes are described in the rule and in
the document, Technical Notes on Drinking
Water Methods (Tech Notes), October 1994
(NTIS order number PB-104766, telephone 800-
553-6847).
Below are answers to questions we have received
about the 1994 methods rule and Tech Notes.
Q. Do I need a copy of Tech Notes in addition
to a copy of the approved method?
A. Yes, because it contains changes to about
25 approved methods and recommends
modifications to several other methods. The
information in Tech Notes corrects or explains
procedures described in the approved methods.
Q. Do I need a copy of the Code of Federal
Regulations or of the 1994 methods rule to have
a complete list of all currently approved
microbiology and chemistry methods?
A. No, Tech Notes conveniently lists all
approved and to-be-withdrawn methods for
primary contaminants, all recommended methods
for secondary contaminant monitoring, and
instructions for continuous chlorine monitoring
under the Surface Water Treatment Rule.
Q. The tables of withdrawn methods (Tech
Notes, pp. 14 - 19) list only methods that are to
be withdrawn on July 1, 1996, and not those
that are replaced by a later version. For
example, Methods 524.2 Rev. 3 and 525.1,
which were replaced by Methods 524.2, Rev. 4
and 525.2, respectively, are not included in these
tables. What is the status of these replaced
versions?
A. Both versions of a replaced method are in
effect until July 1, 1996. EPA noted (59 FR
62461) that the 17-month overlap in approval
periods for the new and old version of a method
gives "laboratories sufficient time to become
certified with the new" version. ALTHOUGH
BOTH VERSIONS ARE APPROVED UNTIL
1996, EPA DISCOURAGES USE OF
OBSOLETE VERSIONS EXCEPT FOR
COMPELLING ECONOMIC REASONS. EPA
listed in Tech Notes as withdrawn, only those
methods for which no updated versions published
by the same organization were approved.
Q. Are there errors in the December 1994
methods update rule?
A. Yes, we found five errors or conflicts, and
four were corrected on June 29, 1995 (60 FR
34084). Please let us know if you find others.
1. The temperature method was cited
differently in §141.23(k)(l) and
§141.74(a)(l). It can be either Standard
Method 2550B or 2550. We chose to cite it
as 2550.
2. The rule states that a footnote specifying
coliform sample transit times and
temperatures will be added at §141.21(f)(3).
-------
However, Footnote 1 in the table at 59 FR
62466 only covers transit time. This is an
error and EPA has revised Footnote 1 to
state that EPA encourages but does not
require systems "to hold samples below
3. The correct holding time for samples
acidified in the laboratory for lead or copper
is 16 hours as cited in the methods and in
Tech Notes (p. 29). However, this conflicts
with the 28-hour instructions cited at
§141.86(b)(2). Because EPA data shows
that 16-hours is sufficient, we: will delete the
28-hour reference in the next revision of the
lead and copper rule.
4. The methods citexl for sulfate in the
regulations at §1430?) (59 FR 62471) and on
page 20 of Tech Notes are correct.
However, there is an error on page 1 1 of
Tech Notes. Turbidimetric methods are not
approved or recommended for sulfate.
ASTM D5 16-90 should be deleted and SM
4500-SO4-E should be 4500-SO4-C, D.
5. The rule appears to delete the maximum
trihalomethane potential (MTP) test in Part
III of Appendix C of §141.30. This
typographical error has been corrected. The
MTP test is now cited at §141.30(g) and has
been revised to delete references to EPA
Methods 501.1 and 501. 2.
Q. Systems may reduce trihalomethane (THM)
monitoring frequencies if they pass the MTP
test. If a system fails this test because
insufficient residual chlorine is present at the end
of seven days, may the system use EPA Method
510.1 to repeat the test?
A. No. Although it is listed in EPA's
laboratory certification guidance manual, Method
510.1 was never approved and it is not supported
by the Agency. There is no federal provision for
an alternative to the MTP test at §141.30(g).
Q. Is the Colisure test complete in 28 or 24
hours? The table at §141.21(f)(3), in the 1994
rule (59 FR 62466), specifies 28 hours but some
people say 24 hours is sufficient.
A. Both answers are correct depending on the
test result. Negative coliform results require at
least 28-hours (and no more than 48 hours) of
incubation to confirm. But a positive coliform
result may be reported after 24 hours.
Q. Must the turbidity of a sample for metals be
checked? Why?
A. Yes. Turbidity is one of the parameters
checked to determine if an acid digestion is
required. The turbidity of the unfiltered sample
must be measured. It must be measured anytime
after the acid preservation step is completed.
Acid preservation is complete after 16 hours.
(Tech Notes p.29).
Q. May volatile organic chemical (VOC)
samples be acidified after the sample is returned
to the laboratory?
A. No. The sample must be dechlorinated and
then acidified at the time of collection to prevent
decomposition of VOCs en route to the
laboratory. (Tech Notes, p. 34)
Q. In Method 504.1, the holding time has been
decreased to 14 days and the requirement for
acid preservation has been deleted. If analyzing
only for EDB and DBCP, may I hold the sample
for 28 days and do I need to add acid? What are
the requirements for analysis of 1,2,3-
trichloropropane (TCP) with Method 504.1?
-------
A. There is a conflict between Methods 504 and
504.1. Until Method 504 is withdrawn in 1996,
laboratories may use either method for EDB and
DBCP as follows: Method 504 (with acid and a
28-day holding time) or Method 504.1 (without
acid and a 14-day holding time). We do not
recommend Method 504.1 for TCP; it is more
economical to measure TCP with the other
VOCs using Methods 502.2 or 524.2 (with acid
and a 14-day holding time).
Q. What derivatizing reagents may be used with
EPA Methods 515.1 and 515.2?
A. Either diazomethane or
trimethylsilyldiazomethane (TMSD) may be
used. (Tech Notes, p. 37)
Q. I want to use the SPE procedure in Method
515.2 rather than the LLE procedure in Method
515.1. May I use Method 515.2 to measure
dalapon?
A. No. Dalapon is not in the scope of Method
515.2, because we have been unable to routinely
achieve acceptable recoveries. We are not sure
why recoveries are not as acceptable as with
Method 515.1. It is possible that resin-based
SPE media do not recover dalapon as well as
ethyl ether extraction. The volatility of the ester
may be a factor. Utah reported (August 1994
Labcert Bulletin) improved recoveries for
dalapon and other Method 515.1 analytes by
changing the evaporation procedure.
EPA realizes some laboratories prefer SPE to
LLE procedures, and are frustrated by the
absence of dalapon in Method 515.2. One
laboratory reports low (40%) dalapon recoveries
with good precision (8%) using Method 515.2
procedures. These low recoveries may be
acceptable, if they are reproducible (e.g., a
precision of 20% or better) and include use of a
surrogate compound to accurately track dalapon
recovery under Method 515.2 conditions. We
cannot rule out that Method 515.2 could be
acceptable for dalapon, but we need data before
we could consider revising the method. If you
have data, send it to the editors of the Labcert
Bulletin.
Q. Ammonium chloride can be used to
dechlorinate samples for THM analysis with
EPA Method 551. Can it be used in other
approved THM methods?
A. No. Currently, ammonium chloride is
specified only in Method 551 and only for THMs
and haloacetonitriles.
Q. Method 551 does not require acidification of
the sample if only THMs are to be determined
(Sect. 8.1.1), but it is not clear that this is true if
Methods 524.2 or 502.2 are used. What do you
suggest?
A. If only THMs are to be measured,
acidification of the sample is only required if
ascorbic acid is used as the dechlorinating agent.
(60 FR 34086 and Tech Notes, pg 53)
Q. What, if any, methods proposed for
withdrawal were not withdrawn in the 1994 rule
because of public comment?
A. EPA Methods 150.1 and 150.2 (pH), 245.2
(mercury) and 515.1 (herbicides) were retained
based on public comment.
Q. Are there plans for another methods update
rule, and what might it contain?
A. We hope to propose a rule containing new
methods soon. We also wish to change the
methods approval process so that future drinking
(Continued on Page 9)
-------
REGULATED DRINKING WATER CONTAMINANTS (a)
INORGANICS
PROPOSED RADS
PARAMETER
REGULATED
Alkalinity4
Asbestos1
Chloride1
Residual Disinfectant*
Free Chlorine
Total Chlorine
Chlorine Dioxide
Ozone
Color1
Conductivity4
Cyanide1
Fluoride1
Foaming Agents'
Nitrate (as N)1
Nitrite (as N)1
Nitrate/Nitrite (as N)1
Odor1
pH14
o- Phosphate4
Solids(TDS)1
Sulfateu
Temperature4
Adjusted Gross Alpha*
Beta Particle Emitters'
radioactive Cesium
radioactive Iodine
radioactive Strontium
tritium
gamma& photon emitters
Radium-226'
Radium-228*
Radon-222'
Uranium*
MCL/
[SMCL]W
mg/L
-
7MF/L>10/zm
[250]
detectable
[15cu]
-
OJ
4.0
[2.0]
[0.5]
10
1
10
|3 tou |
6.5-8.5
[6.5-8.5]
-
[500]
deferred
[250]
-
15pCi/L
4 mr ede/yr
-
-
-
-
-
20 pCi/L
20 pCi/L
300 pCi/L
0.02
MCLG10
mg/L
-
7MF/L>10jon
-
-
-
0.2
•
-
10
1
10
-
-
••
-
deferred
-
zero
zero
-
-
-
-
-
zero
zero
zero
zero
METHODS" ACCEPTANCE
LIMITS11
D1067-92B, 2320B, 1-1030-85
100.1, 100.2
300.0, D4327-91, 4110, 4500-C1-D
4500-C1 D, F, G and H
4500-C1 D, E, F, G and I
4500-C1O, C, D, E
4500-O, B
2120B
Dl 125-91 A, 2510B
335.4, D2036-91B, D2036-91A,
4500-CN-C, G, E and F, 1-3300-85
300.0, D4327-91, D1179-93B,
4110B, 4500F-B, D, C and E,
Technicou 380-75 WE and 129-71 W
5540C
353.2, 300.0, D4327-91, D3867-90A&B
4110B, 4500-NO,-F, D and E,
Waters B-1011, ATI 601
353.2, 300.0, D4327-91, D3867-90A&B
4110B, 4500-NOj-F & E, 4500-NO2-B
Waters B-1011
-
2150B
150.1, 150.2, D1293-84, 4500-H+-B
365.1, 300.0, D515-88A, D4327-91,
4500-P-F, 4500-P-E, 4110,
1-1601-85, 1-2601-90, 1-2598-85
2540C
300.0, 375.2, D4327-91,
4110, 4500-SO4-F, C and D
2550
900.0
900.0
901.0
902.0
905.0
906.0
901.1
903.0, 903.1
904.0
903.1, 913.0
908.0, 908.1
2SD
±25%
±10%
.
±10%
±15%
±50%
±30%
±30%
±30%
±30%
±20%
±30%
±50%
±30%
±30%
-------
MICROBIOLOGICAL CONTAMINANTS
VOLATILE ORGANICS
PARAMETER
REGULATED
Turbidity*
Total Conform*"
E. coliu
Fecal Coliform*'"
Giardia lamblia*
Heterotrophk Bacteria or
Residual Disinfectant*
Legionella'
Viruses*
Trihalomethanes (Total)
Benzene
Carbon tetrachloride
Chlorobenzene1
p-Dichlorobenzene
o-Dichlorobenzene1
1 ,2-Dichloroethane
1 , 1-Dichloroethylene
c-1 ,2-Dichloroethylene1
t-1 ,2-Dichloroethylene1
Dkhloromethane1
1 ,2-Dichloropropaue1
Ethyl benzene1
Styrene3
Tetrachloroethylene1
Toluene1
1 ,2 ,4-Trichlorobenzene*
1,1,1-Trichloroetbane
1,1,2-Trichloroethane*
Trichloroethyleue
Vinyl chloride
Xylenes(Total)1
MCL/
[SMCL]10
mg/L
Treatment
100/lOOmL*
5% positive
samples/mo11
BW1"
5141.21(0(5)
8141.74(a)(l)
Treatment
Treatment
Treatment
Treatment
0.10
0.005
0.005
0.1
0.075
[0.005]
0.6
0.005
0.007
0.07
0.1
0.005
0.005
0.7
0.1
0.005
1
0.07
0.2
0.005
0.005
0.002
10
MCLG10
mg/L
-
zero
zero
zero
zero
-
zero
zero
zero
zero
0.1
0.075
0.6
zero
0.007
0.07
0.1
zero
zero
0.7
0.1
zero
1
0.07
0.2
0.003
zero
zero
10
METHODS4'7 ACCEPTANCE
LIMITS"
180.1, 2130B, GLI Method 2
TCR (9221A,B,D, 9222A,B,C,
9223, Colisure)
SWTR (9221A,B,C, 9222A,B,C, 9223)
Colilert, Colisure, EC-MUG"
Nutrient Agar-MUG"
TCR (9221E Part 1)
SWTR (922 IE Part 1&2, 9222 D)
9215B(HPC)
4500 series (disinfectants)
502.2, 524.2, 551
502.2, 524.2
502.2, 524.2, 551
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2
502.2, 524.2, 551
502.2, 524.2
502.2, 524.2
502.2, 524.2, 551
502.2, 524.2
502.2, 524.2, 551
502.2, 524.2
502.2, 524.2
±20%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
±20/40%
-------
SYNTHETIC ORGANIC CONTAMINANTS
PARAMETER
REGULATED
Alachlor*
Atrazine1
Carbofuran1
Chlordane1
2,4-D*
Dalapon2
Dibromochloropropane1
Dinoseb2
Diquat2
Endothall1
Endrin1
Ethylenedibroniide(EDB)1
Glyphosate1
Heptachlor3
Heptachlor epoxide1
Lindane*
Methoxychlor1
Oxamyl* (Vydate)
PentachlorophenoP
Picloram1
Siniaziue2
Toxaphene1
2,4,5-TP(Savex)J
Hexachlorobenzene*
Hexachlorocyclopeutadiene1
Benzo(a)pyrene2
PCBs1 (as Aroclors)
(as decachlorobipbenyl)
2,3,7,8-TCDD( Dioxin)1
Acrylauiide1
Epkhlorohydriii1
Di(2-etbylhexyl)adipate2
Di(2-ethylhexyl)phthalateI
MCL/
[SMCL]10
mg/L
0.002
0.003
0.04
0.002
0.07
0.2
0.0002
0.007
0.02
0.1
0.002
0.00005
0.7
0.0004
0.0002
0.0002
0.04
0.2
0.001
0.5
0.004
0.003
0.05
0.001
0.05
0.0002
0.0005
3x10*
Treatment
Treatment
0.4
0.006
MCLG"
mg/L
zero
0.003
0.04
zero
0.07
0.2
zero
0.007
0.02
0.1
0.002
zero
0.7
zero
zero
0.0002
0.04
0.2
zero
0.5
0.004
zero
0.05
zero
0.05
zero
zero
zero
zero
zero
0.4
zero
METHODS5-7 ACCEPTANCE
LIMITS"
505, 507, 508.1, 525.2
505, 507, 508.1, 525 J
531.1, 6610
505, 508, 508.1, 525.2
515.1, 515.2, 555
515.1, 552.1
504.1, 551
515.1, 515.2, 555
549.1
548.1
505, 508, 508.1, 525.2
504.1, 551
547, 6651
505, 508, 508.1, 525.2
505, 508, 508.1, 525.2
505, 508, 508.1, 525.2
505, 508, 508.1, 525.2
531.1. 6610
515.1, 515.2, 525.2, 555
515.1, 515.2, 555
505, 507, 508.1, 525.2
505, 508, 525.2
515.1, 515.2, 555
505, 508, 508.1, 525.2
505, 508, 508.1, 525.2
550, 550.1, 525.2
505, 508
508A
1613
506, 525.2
506, 525.2
±45%
±45%
±45%
±45%
±50%
2SD
±40%
2SD
2SD
2SD
±30%
±40%
2SD
±45%
±45%
±45%
±45%
2SD
±50%
2SD
2SD
±45%
±50%
2SD
2SD
2SD
0-200%
2SD
2SD
2SD
-------
METALS
PARAMETER
REGULATED
Aluminum'
Antimony1
Arsenic
Barium1
Beryllium1
Cadmium1
Calcium
Chromium1
Copper4'1
Iron1
Lead4
Manganese1
Mercury1
Nickel1
Selenium1
Silica4
Silver1
Sodium
Thallium1
Zinc1
MCL/
[SMCL]10
mg/L
[0.05-0.2]
0.006
0.05
2
0.004
0.005
-
0.1
1.3/90%4
[1.0]
[0.3]
0.015/90%4
[0.05]
0.002
MCLG10
mg/L
-
0.006
-
2
0.004
0.005
-
0.1
1.3
-
zero
-
0.002
Remanded14
0.05
-
[0.1]
20'°
0.002
[5.0]
0.05
-
-
0.0005
-
METHODS57 ACCEPTANCE
LIMITS"
200.7,200.8,200.9,31208,31138,31110
200.8, 200.9, D-3697-92, 3113-B
200.7, 200.8, 200.9, D-2972-93C,
3120B, 3113B, 3114B, D-2972-93B
200.7, 200.8, 3120B, 3111D, 3113B
200.7, 200.8, 200.9, D-3645-93B,
3120B, 3113B
200.7,200.8,200.9,31138
200.7, D511-93A, D511-93B,
3500-Ca-D, 3111B, 3120B
200.7, 200.8, 200.9, 3120B, 3113B
200.7, 200.8, 200.9, D1688-90C,
D1688-90A, 3113B, 3111B, 3120B
200.7, 200.9, 3120B, 3111B, 3113B
200.8, 200.9, D3559-90D, 3113B
200.7,200.8,200.9,3120B,3113B,3111B
245.1,245.2,200.8,03223-91,31128
200.7,200.8,200.9,31208,31118,31138
200.8, 200.9, D3859-93A, D3859-93B,
31148,31138
200.7, D859-88, 4500-Si-D,E,& F,
3120B, 1-1700-85, 1-2700-85
200.7, 200.8, 200.9,
3120B, 31118, 3113B, 1-3720-85
200.7, 311B
200.8, 200.9
200.7, 200.8, 3120B, 3111B
±15%
±15%
±15%
±20%
±15%
±10%
±30%
±30%
±15%
±20%
±30%
a - This method table is a convenient reference only: for details see the rules
1 - Secondary Maximum Contaminant Level - non-enforceable federal guidelines for aesthetic quality
2 - Phase V Regulations - promulgated 7-17-92
3 - Phase II Regulations - promulgated 1-30-91 and 7 1-91
4 - Lead and Copper Rule - promulgated 6-7-91; lead and copper levels are Action Levels
5 - Secondary contaminants may be analyzed using the recommended methods; Primary, unregulated
(monitoring only) and state discretionary contaminants must be analyzed using approved methods
in laboratories certified by the States.
6 - Radionuclides Proposed Rule - 7-18-91
7 - For method references, see 59 ER 62456, December 5, 1994 and TM-hniral Nntre nn Drinking Wat^r
Methods, EPA-600/R-94-173, October, 1994
8 - Surface Water Treatment Rule - promulgated 6-29-89
9 - Recommended level
10 - MCL=maximum contaminant level; SMCL=secondary maximum contaminant level; MCLG = maximum contaminant level goal
11 - see CFR 141 Jl(e)(6&7)
12 - Coliform Rule - promulgated 6-29-89
13 - PE Acceptance Limits for VOCs are ±20% at *N)Mg/L and ±40% at <10//g/L
14 - The MCL and MCLG for nickel were remanded by court order on 2-23-95. Monitoring and analytical requirements remain the same.
-------
and wastewater method updates are more
coordinated and promulgated faster. Future
updates may include the following: the 19th
edition of Standard Methods, the current ASTM
Annual Book of Standards, a revised EPA
organic methods manual, EPA membrane filter
Method 1104 for coliforms, and the EPA
radionuclide methods which were proposed on
July 18, 1991 (56 FR 33123-33125).
Q. The sample or extract holding times for
some analytes differ depending on the method
used. Examples of this are the extract holding
times for endothall in Methods 548 and 548.1,
and the sample holding times for heptachlor in
Methods 505 and 525.2. What should I do?
A. Use the holding time in the method of
choice. Holding times may vary because of
differences in the analytical method. For
example, the hydrazine derivative formed with
the Method 548 procedure is less stable than the
methyl derivative measured in Method 548.1.
Thus, Method 548.1 extracts may be held
longer. The holding time for heptachlor in
Method 525.2 is longer than in Method 505
because heptachlor is more stable using the
sampling and preservation procedures in Method
525.2. Differences also can occur when
methods that do not contain the same set of
analytes are compared. These differences occur
because holding times and sample collection
procedures are routinely optimized for most or
all of the analytes in the method rather than for
a single analyte.
Q. Does the change in section 9.3.3 of Method
524.2 (Tech Notes, p. 40) mean that the
continuing calibration criteria for Method 502.2
are changed from ±20% to ±30%?
A. No. The continuing calibration and
laboratory fortified blank accuracy criteria for
Method 502.2 remain at ±20%. Changes to the
quality assurance and calibration sections of
methods 502.2 and 524.2, were discussed in
Tech Notes beginning on page 40. The
requirements are listed in the table below.
Quality Assurance & Calibration Requirements for Methods 502.2 and 524.2
Method
502.2
section
524.2
section
IDC
Accuracy
±20%
10.3.3
±20%
9.3.3
ccc
Accuracy
±20%
9.2.2
±30%
10.3.5
LFB
Accuracy
±20%
10.5
±30%
9.6
CCC
may equal
LFB?
Yes
9.2.2 & 10.5
Yes
10.3 & 9.6
FRB
may be substituted for
LRB?
No
10.6 & 10.4
No
9.7 & 9.6
FRB
required only if
samples are positive?
Yes
10.6
Yes
9.7
CCC every shift or 12
hours?
Yes
9.2.2
Yes
10.3
IDC = initial demonstration of capability
CCC = continuing calibration check
LFB = laboratory fortified blank
FRB = field reagent blank
LRB = laboratory reagent blank
For additional information or clarification on the 1994 Methods Rule, contact the Safe Drinking Water
Hotline, 800 426-4791 or Richard Reding, 513 569-7946.
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PCB Analyses and
Compliance
We have received many questions recently
about monitoring for PCBs because this is
the last period in the monitoring cycle to comply
with this requirement. The following
recommendations have been excerpted from a
guidance memo from OGWDW to the EPA
Regional certification officers. This guidance does
not change the monitoring triggers in the
regulation, but rather suggests optional procedures
the states may adopt if they wish to lower their
detection limits for Aroclors.
A PCB-compliance sample should be analyzed first
for Aroclors using Method 505 or 508. If an
Aroclor is detected, then a duplicate sample must
be analyzed by Method 508A and positive results
must be quantified and reported as
decachlorobiphenyl to determine compliance with
the MCL for PCBs. Negative Aroclor results from
Methods 505 and 508 should be reported as "not
detected" along with the laboratory's detection
limit for each Aroclor.
Although a method detection limit, calculated
according to 40 CFR 136 Appendix B1, is a useful
benchmark for evaluating and comparing method
sensitivity, it may not be an appropriate indicator
of the level at which an Aroclor can be identified.
We recommend that an Aroclor detection limit or
U.S. EPA Method 8081 (SW846) offers two options for
quantitation of PCBs. One option uses the total area of the
chlorinated biphenyl peaks and the other option uses the
response of 3-5 major peaks (with capillary columns, we
would recommend 7-10 peaks). A major peak is defined as
one whose height is at least 25 % of the height of the largest
chlorinated biphenyl peak. Either of these options would be
appropriate to use in the calculation of the MDL.
pattern recognition level (PRL) be defined as the
lowest level at which recognition of the Aroclor
peak profile (pattern) is possible. A PRL should
be determined for each of the seven Aroclors in
both reagent and tap water. Document how the
PRLs were determined. Because this recognition is
subjective, the limits should be determined by the
same person who analyzes the compliance samples
or interprets the quality control and compliance
data. The table below lists the concentrations of
the Aroclors that are equivalent to 0.0005 mg/L of
decachlorobiphenyl.
If detection limits lower than those specified in the
regulations are desired, we recommend Method
508 over Method 505, because the higher solvent
to water ratio should increase the sensitivity of the
Aroclor screen. Sensitivity may also be increased
by concentrating the Method 508 extract to less
than the usual 5-mL. The success of this technique
may vary with the quality of water, because,
although concentration may improve Aroclor
sensitivity in a reagent water spike, it may not in
a tap water sample because concentration would
also increase interfering impurities that may be
present in the extract.
10
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Aroclor
1016
1221
1232
1242
1248
1254
1260
Equivalency Factor*
1.92
2.63
2.17
1.92
1.67
1.52
1.39
Aroclor Concentration
0.00026
0.00019
0.00023
0.00026
0.00030
0.00033
0.00036
DCBP Concentration
0.0005
0.0005
0.0005
0.0005
0.0005
0.0005
0.0005
* based on the percent chlorination of the Aroclor compared to decachlorobiphenyl and
assuming 100% conversion (see method 508A, table 1)
Federal regulations require use of an Aroclor
screening method, but omit the requirement that
a laboratory be certified for Aroclor
identification. In response to state requests for
guidance on how to approve or certify a
laboratory for Aroclor screening, we recommend
provisional certification using six criteria.
1. We recommend that
certified for Method 508
regulated contaminants
analyses. Although we
only laboratories
or 505 for other
conduct Aroclor
recommend using
Method 508 more than 505, Method 505 may be
used if the laboratory can achieve the necessary
detection limits or PRLs.
2. Because laboratories may subcontract Method
508A analyses, we note that provisional
certification for Aroclors only does not require
the laboratory to be certified for Method 508A.
3. Use only laboratories that achieve satisfactory
Aroclor PRLs. It is important to observe the
chromatogram produced at the laboratory's PRL
to verify the laboratory can recognize the
Aroclor at that level.
4. In the PCB compliance monitoring scheme,
Method 505 or 508 is used for identification and
detection but not quantitation of Aroclors;
therefore, some quality control requirements in
the methods are unnecessary for Aroclor
screening. For example, a calibration curve that
is verified daily for each Aroclor is not necessary
for compliance monitoring. However, a matrix
spike is appropriate because it is important to
know that the Aroclors can be identified in the
sample.
5. Because it is important to verify Aroclor
detection limits regularly, we recommend daily
analysis of a laboratory fortified blank of a
different Aroclor at the PRLs each analytical
day. This schedule verifies the detection limit
for each Aroclor every seven analytical days.
6. The PCB PE sample provided by EMSL for
decachlorobiphenyl by Method 508A may also
be used for Aroclors by Method 508 or 505. We
suggest the laboratory identify the Aroclor
present using Method 508 or 505. After the PE
study is complete, EMSL will provide the
identity and true value of the Aroclor which was
present in the PE.
Questions or comments may be directed to your
State or Regional certification officer or Mary
Ann Feige at 513 569-7944.
11
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Upcoming Meetings
WEF Annual Conference
October 21-25, 1995, Miami Beach, FL
703 684-2400
APHA Annual Conference
October 29-November 2, 1995, San Diego, CA
202 789-5600
AWWA Water Quality Technology Conference
November 12-16, 1995, New Orleans, LA
303794-7711.
United States
Environmental Protection Agency
Office of Ground Water and Drinking Water
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
EPA-814N95001
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
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