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.

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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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