United States ^     Office of Water     EPA # 815-R-99-004
         Environmental Protection Agency 4607        August 1999

M^EPA   Unregulated
         Contaminant Monitoring
         Regulation Analytical
         Methods and Quality
         Control Manual
                             Printed on Recycled Paper

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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


                                     Foreword


 This document provides guidance regarding sampling, analytical methods, and related quality control
 issues tor the States, EPA offices, water systems, and analytical laboratories participating in the
 Unregulated Contaminant Monitoring Regulation (UCMR) Program. This document is written for
 the personnel at a water system, laboratory, or agency who will be responsible for UCMR Program
 planning, implementation, and oversight.

 Under the Safe Drinking  Water Act (SDWA) as amended  in  1996,  §1445(a)(2)(A)  the
 Environmental Protection Agency (EPA) is to promulgate regulations for a monitoring program for
 unregulated contaminants by August 1999.  In the past, unregulated contaminant monitoring has
 been performed according to the program described in CFR 141.40. The 1996 SDWA Amendments
 direct a substantially revised UCMR Program.

 The revised UCMR Program has a new list of contaminants to monitor, changes the number of
public water systems (PWSs) that must conduct monitoring, and changes the frequency and schedule
lor monitoring.  Additional regulatory actions include cancellation of unregulated contaminant
monitoring for small systems serving  10,000 or fewer people under the existing  unregulated
contaminant monitoring program begun in 1989.  The data collected in the revised UCMR will be
used to  support  the development of the Contaminant Candidate List (CCL), to  support the
Administrator's determination of whether to regulate a contaminant, and to support the development
oi future regulations.  The revised monitoring program is one of the cornerstones of the sound
science approach to future drinking water regulation that is an aim of the 1996 SDWA Amendments.

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                                    Disclaimers


This guidance document is designed to implement national policy concerning the UCMR Program
The document does not,  however, substitute for the SDWA or EPA's regulations nor is this
document a regulation itself. Thus, it cannot impose legally-binding requirements on EPA, States,
or the regulated  community, and may  not  apply  to a particular  situation based upon  the
circumstances. EPA decision makers retain the discretion to adopt approaches on a case-by-case
basis that differs from this guidance where appropriate. EPA may change this guidance hi the future.

Mention of trade names or commercial products does not constitute endorsement or recommendation
for use.
                                         m

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                               Acknowledgments


 'S^S^aeat was PrePared m support of the Unregulated Contaminant Monitoring Regulation
 (UCMR) for EPA's Office of Ground Water and Drinking Water. Charles Job served as EPA's team
 leader for development of the UCMR and James Taft as Targeting and Analysis Branch Chief.
 Rachel Sakata and Yvette Selby served as Work Assignment Managers. The UCMR Work Group
provided technical guidance throughout, in particular David Munch, James Sinclair, and Jeanne
 Campbell provided scientific and editorial guidance.  External expert reviewers  and many
stakeholders provided valuable advice to improve the UCMR Program and this document  The
Cadmus Group, Inc., served as the prime contractor providing support for this work. The major
contributions of Chris Higgins, Jonathan Koplos, and Maureen Devitt are gratefully acknowledged
as are the contributions of UHL subcontractors Michael Wichman, George Breuer Nelson Mover
and others.  George Hallberg served as Cadmus' Project Manager.                           '

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                               Table of Contents


 Foreword	  _                       I

 Disclaimers	             ^

 Acknowledgments  	                   v

 Section 1. Introduction	      j
      1.1   Background on the Unregulated Contaminant Monitoring Regulation (UCMR) !.. 1
      1.2   The Unregulated Contaminant Monitoring Regulation	             1
      1.3   Contaminants on the UCMR (1999) List	                	3
       1.3.1  UCMR (1999) List 1 Contaminants	     '	'	6
       1.3.2  UCMR (1999) List 2 and List 3 Contaminants	      	7
      1.4   Analytical Methods for UCMR (1999) List 1 Contaminants	.!..!.. 9

 Section 2. Sampling Plan	,	                    13
     2.1   Monitoring By Public Water Systems	'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.-     13
       2.1.1  Systems Required To Monitor	  13
     2.2   Sampling Frequency	'.'.'.'.'.'.'."'  13
     2.3'   Sampling Points	  14

 Section 3. Sample Collection and Preservation	15
     3.1   Chemical Contaminants  	'.'.'.'.'.'.'.'. 15
       3.1.1  Nitrogen- and Phosphorus-Containing Pesticides	 15
       3.1.2  Chlorinated Hydrocarbon Pesticides	 16
       3.1.3  Acid Herbicides	'.'.'.'.'.'.'.'.'.'. 19
       3.1.4  Volatile Organic Compounds	.20
      3.1.5  Semi-volatile Organic Compounds 	'..... .22
     3.2   Monitoring of Routine Water Quality Parameters	.24

Section 4. Sample Transport	          27

Section 5. UCMR Quality Control Requirements	           29
     5.1    Minimum Reporting Level	'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.	30
     5.2    Calibration	'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.	31
      5.2.1  Calibration Verification	    32
     5.3    Method Detection Limit	*'	35
     5.4    Laboratory Reagent (Method) Blank 	'.'.'.'.'.'.'.'.'.'.'.'.	35
      5.4.1  Field Reagent Blank (Shipping or Travel Blank)	'.'.'.'.'.'.	38
     5.5    Quality Control Sample	   3%
     5.6    Sample Matrix Spike and Matrix Spike Duplicate	   	      38
     5.7    Internal Standard	;	 41
     5.8    Surrogate Standard	'...'.'.'.'.*.'.'.'.'.'.	43
     5.9    Confirmation	45
      5.9.1  Gas Chromatographic Methods	'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.    45
      5.9.2  Gas Chromatography/Mass Spectrometry Confirmation '.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.. 45


                                       vii

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       5.9.3  Mass Spectrometry Methods	46
     5.10  Additional Quality Controls	47

Section 6. Additional Analytical Method Specifications	49
   6.1     Clarifications Concerning EPA Methods 515.1 and 515.2 and the Approved
          Equivalent Methods	49
   6.2    Recommendations for EPA Method 524.2 and the Approved Equivalent
          Methods	49

Section 7. Reporting  	51
   7.1     Public Water Systems Reporting to EPA	'..'.'.'.'.'.'.'.'.51
     7.1.1  Reporting of Results Obtained for the DCPA Mono- and Di-Acid Degradates ... 51
     7.1.2  Reporting of Data Below the Specified Minimum Reporting Level  	51
     7.1.3  Reporting of Water Quality Parameter Data	52
   7.2     Public Notification of Results (Report of PWS to Consumers)	52
                                        vm

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 UCMR Analytical Methods and Quality Control Manual
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                                   List of Tables
 Table 1.1    UCMR (1999) Contaminants	3
 Table 1.2    UCMR (1999) List 1 Contaminants	6
 Table 1.3    UCMR (1999) List 2 Contaminants	7
 Table 1.4    UCMR List 3 (1999) Contaminants		8
 Table 1.5    Approved Analytical Methods for UCMR (1999) List 1 Contaminants	10

 Table 3.1    Preservation and Holding Times for Approved Analytical Methods	24
 Table 3.2    Water Quality Parameters to be Monitored with UCMR (1999) List 1
            Contaminants 			 25

 Table 5.1    UCMR Methods and Minimum Reporting Level	30
 Table 5.2    Frequency Requirements for Verifying Calibration 	33
 Table 5.3    UCMR Low-Level Calibration Check Standard Concentrations and
            Acceptance Criteria	„	 33
 Table 5.4    Mid-Level Calibration Check Standard Concentrations and Acceptance
            Criteria	34
 Table 5.5    Frequency Requirements for Analyzing Laboratory Reagent (Method) Blanks... 36
 Table 5.6    UCMR Acceptance Criteria for Laboratory Reagent (Method) Blanks	37
 Table 5.7    Requirements for Performing Spiked Sample Analyses	39
 Table 5.8    Concentrations for Spiking MS/MSD Samples	41
 Table 5.9    Requirements for Internal Standard Analyses	42
 Table 5.10   Requirements for Surrogate Standard Analyses	44
 Table 5.11   Recommended Confirmation Ions	46
 Table 5.12   Maximum Holding Times for Samples and Extracts	47

 Table 7.1    UCMR Reporting Requirements		.		53


                                   Appendices

Appendix A. Abbreviations and Acronyms	   A-l
Appendix B.Definitions	B_l
Appendix C. Procedure for Determination of Method Detection Limits	C-l
                                         IX

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  Section 1. Introduction

  1.1    Background on the Unregulated Contaminant Monitoring Regulation (UCMR)

  The requirement to monitor unregulated contaminants was established by the 1986 Amendments to
  the Safe Drinking Water Act (SDWA). Public water systems (PWSs) were required to report the
  monitoring results for up to 48 unregulated contaminants to the States or primacy agency under
  several regulations (40 CFR141.40(e), Q), and (n)(l 1) and (12)). Systems with less than 150 sem'ce
  connections were exempt, provided those systems made their facilities available for the States to
  monitor. The rules require repeat monitoring every 5 years.
 Under §1445(a)(2)(A) of the SDWA, as amended in 1996, the Environmental Protection Agency
 (liFAiistonrnmnlcyat^rpcmlfltirknctfiQ-f«/;il onUo+rt~-*-;«iu,,.~, •	*i	:-*•	    -,  .  ,     ,&  . J
 new list of contaminants, changes the PWSs that must conduct monitoring, and changes the
 frequency and schedule for monitoring.                                             &

 S^UC?ff hf? be™ dev£oped in coordination with the Contaminant Candidate List (CCL) and the
 National Drinking Water Contaminant Occurrence Database (NCOD). The UCMR and the GCL will
 operate on an evolving 5-year cycle to assess the impact of new drinking water contaminants. The
 data collected through the UCMR Program will be used to support the development of the
 subsequent CCL, to support the Administrator's determination of whether or not to regulate a
 contaminant  and to develop regulations. The revised monitoring program is part of a sound science
 approach to future drinking water regulation, which is an aim of the 1996 SDWA Amendments.

 The revised UCMR includes new and emerging contaminants. The revised UCMR will also require
 tewer systems to conduct monitoring than is required in the existing unregulated contaminant
 monitoring program. Therefore, the quality-of data collected is a very important issue for the success
 of the revised program. This document provides a brief overview of the revised UCMR and outlines
 the required  analytical methods and quality control  procedures that PWSs and participating
 UCMR°neS mUSt     rC t0 WWle  imPlementinS ft6 Assessment Monitoring component of the
 Further detailed information about the revised UCMR Program can be found in the Preamble to the
 proposed regulation (64 FR 23398) and the final Rule (64 FR      ), as well as oAerTuppor\nig
           o?S? d°cumen-S!re Bailable from the EPA. WateFDodcet, (202) 260-302?;Docket

                           °n        b£ °btained fr°m ** EPA Safe Drinking Water
1.2    The Unregulated Contaminant Monitoring Regulation

The UCMR is required by SDWA as amended in 1996.  Under the 1996 Amendments  EPA is
mn«trf^f^Pr0m?gate a nrW I^ulatKm .for monitoring unregulated contaminants. The regulation
must include: (1) a new list of contaminants, of which not more than 30 may be required for
monitonng, (2) a frequency and schedule for monitoring as based on PWS size, source water type
and likelihood of finding contaminants; (4) monitoring of only a representative sample of PWSs

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serving 10,000 or fewer people; and, (5) requirements for placement of the monitoring data in the
NCOD (in accordance with §1445 (g) of SDWA).  PWSs must monitor to provide the location,
concentration, and related information regarding the occurrence of these contaminants in public
drinking  water.  EPA will analyze the monitoring data to identify which contaminants occur
nationally and at concentrations  that may warrant regulation.   EPA will  determine  which
contaminants pose the greatest risks to human health and, if necessary, will set priorities for
regulation of the contaminants. Conversely, EPA may remove contaminants from consideration for
regulation if UCMR monitoring indicates that these contaminants are not detected at significant
levels hi drinking water.  EPA was required to develop a list of contaminants, the UCMR (1999)
List, and regulations for monitoring the contaminants by August 1999. This list will be revised every
5 years.

EPA used the CCL (1998) contaminants  listed as occurrence priorities as the primary basis for
selecting contammants for the UCMR (1999) List. The CCL identifies contaminants of potential
concern that may occur or are likely to occur in drinking waten In order to establish the CCL (1998),
EPA convened a Work Group to develop the  CCL based on the results of previous unregulated
contaminant monitoring and information from other data sources. The CCL team worked from a
compendium of 10 lists containing approximately 391 chemical contaminants. The lists used hi this
process were: 1991 Drinking Water Priority List; Health Advisories; Integrated Risk Information
System; Non-Target Analytes in Public Water Supply  Samples; Comprehensive Environmental
Response, Compensation, and Liability Act Priority List; stakeholder responses; Toxic Release
Inventory; pesticides identified by the EPA Office of Pesticide Programs; a list of contaminants
identified by the Safe Drinking Water Hotline; and a list of contaminants suspected of causing
endocrine disruption.

The National Drinking Water Advisory Council's Working Group on Contaminant Occurrence and
Selection, formed under the Federal Advisory Committee Act, developed the criteria for the CCL
to address a contaminant's potential risk to public health and frequency of contaminant occurrence.
Criteria for selecting contaminants for the CCL focused on occurrence hi water at levels of health
concern or indications of occurrence (production and release, coupled with contaminant properties).
Health effects concentrations were used to determine the significance of occurrence. The CCL
(1998) contains 50 chemical contaminants and 10 microbiological contaminants.

In establishing the CCL (1998), EPA divided the contaminants into three priority categories: those
contaminants requiring additional research; those which need additional occurrence data; and those
which are priorities for consideration for rule-making. EPA published a draft of the 1998 Drinking
Water  Contaminant Candidate List in the October 6, 1997 Federal Register (62 FR 52193).
Comments submitted hi response to the draft CCL were reviewed and considered in creating the final
CCL, which was published hi the March 2,1998 Federal Register (63 FR 10273).

For purposes of the UCMR, EPA initially used the CCL occurrence priorities list to identify
contammants that were of national concern. The UCMR (1999) List, as initially proposed, included
32 of the 34 contammants listed as occurrence priorities on the  CCL (1998). At the time of the
publication of the proposed UCMR, perchlorate and RDX were excluded from the UCMR (1999)
List because it was thought that their occurrence was only a localized issue. As more data became
available and  after  many public comments  were received supporting the inclusion of these
compounds,  both perchlorate and RDX, as well as lead-210 and polonium-210, were added to the
UCMR (1999) List.

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 UCMR Analytical Methods and Quality Control Manual
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 1.3    Contaminants on the UCMR (1999) List

 Although only 32 contaminants (24 chemical and 8 microbiological contaminants) listed on the CCL
 as occurrence priorities were initially proposed for inclusion on the UCMR (1999) List  all 34
 f ?rS n^mf*? aloccmFfn?e Priorities on the CCL (1998) were eventually included on the final
 ™ t^#?T ?i oaS Tw° ^ditional contaminants lead-210 and polonium-210, were not included
 on the CCL (1998), but have been found in drinking water and in shallow aquifers in Florida
 Because radionuchdes have potential wide occurrence and consequent health risks and in response
 to public comments, EPA added lead-210 and polonium-210 to the UCMR (1999) List  These 36
 contaminants comprise the revised list of UCMR (1999) contaminants (Table 1.1). For eachofthese
 contaminants, EPA evaluated the availability of analytical methods published by EPA and voluntary
 consensus standard organizations such as American Society for Testing and Materials fASTM} the
 ^ASS?lf°Tn °fOfficial Analytical Chemists (AOAC) and the American Public Health Association
 (APHA). In addition, EPA prioritized analytical methods development activities for those chemical
 and microbiological contaminants that did not have suitable analytical methods currently available.

 The revised UCMR Program consists of three distinct monitoring components  based  upon the
 availability of suitable analytical methods. The Assessment Monitoring component of the UCMR
 Program will monitor for UCMR (1999) List 1 contaminants; these are the UCMR contaminanTs"for
 which analytical methods are currently available.1  These are the only UCMR contamiriants for
 which monitoring is currently required under the revised UCMR Program.

 The other UCMR (1999) contaminants, those on List 2 and List 3, will require monitoring when
 suitable analytical methods are developed. The Screening Survey component of the UCMR Program
 will monitor for UCMR (1999) List 2  contaminants for which analytical methods are nearly
 developed and^which have uncertain potential for occurrence.  The Pre-Screen Testing component
 of the UCMR Program will monitor for UCMR (1999) List 3 contaminants for which analytical
methods are in the early stages of development, and which may have newly emeiged as concerns
 Table 1.1   UCMR (1999) Contaminants
                                 Chemical Contaminants
             Contaminant Name
            2,4-dinitrotoluene
             Potential Environmental Source
Used in the production of isocyanate and explosives
            2,6-dinitrotoluene
Used as mixture with 2,4-DNT (similar uses)
            Acetochlor
                                  Herbicide used with cabbage, citrus, coffee, and corn crops
            DCPA di-acid degradate
Degradation product of DCPA, an herbicide used on grasses and
weeds with fruit and vegetable crops
      The two exceptions to this are perchlorate and acetochlor, for which analytical methods are currently being
      finalized. It is anticipated that these methods will be available before monitoring is to begin in 2001.

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UCMR Analytical Methods and Quality Control Manual
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List
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
3
Contaminant Name
DCPA mono-acid
degradate
DDE
EPTC (s-ethyl-
dipropylthio-carbamate)
Molinate
MTBE (methyl tertiary-
butyl ether)
Nitrobenzene
Perchlorate
Terbacil
1 ,2-diphenylhydrazine
2-methyl-phenol
2,4-dichlorophenol
2,4-dinitrophenol
2,4,6-trichlorophenol
Alachlor ESA
Diazinon
Disulfoton
Diuron
Fonofos
Linuron
Polonium-210
Prometon
RDX
Terbufos
Lead-210
Potential Environmental Source
Degradation product of DCPA, an herbicide used on grasses and
weeds with fruit and vegetable crops
Degradation product of DDT, a general insecticide
Herbicide used on annual grasses, weeds, with potatoes and corn
Selective herbicide used with rice, controls watergrass
Octane enhancer in unleaded gasoline
Used in the production of aniline, which is used to make dyes,
herbicides, and drugs
Oxygen additive in solid fuel propellant for rockets, missiles, and
fireworks
Herbicide used with sugarcane, alfalfa, and some fruit, etc. .
Used in the production of benzidine and anti-inflammatory drugs
Released hi automobile and diesel exhaust, coal tar and petroleum
refining, and wood pulping
Chemical intermediate in herbicide production
Released from mines, metal, and petroleum plants
By-product of fossil fuel burning, used as bactericide and wood/glue
preservative
Degradation product of alachlor, an herbicide used with corn, bean,
peanut, and soybean crops to control grasses and weeds
Insecticide used with rice, fruit, vineyards, and com crops
Insecticide used with cereal, cotton, tobacco, and potato crops
Herbicide used on grasses in orchards and with wheat crops
Soil insecticide used on worms and centipedes
Herbicide used with corn, soybean, cotton, and wheat crops
Part of the uranium decay series; naturally occurring
Herbicide used on annual and perennial weeds and grasses
Used in explosives; ammunition plants
Insecticide used with corn, sugar beet, and grain sorghum crops
Part of the uranium decay series; naturally occurring

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List
Contaminant Name

Microbiological Contaminants
2
3
3
3
3
3
3
3
Aeromonas hydrophila
Adenoviruses
Cyanobacteria (blue-
green algae, other
freshwater algae, and
their toxins)
Caliciviruses
Coxsackieviruses
Echoviruses
Helicobacter pylori
Microsporidia
Present in all freshwater and brackish water
Fecal or hand to mouifh transmission
Bloom in surface water bodies; produce toxins
Contaminated food and water; raw shellfish
Fecal or hand to mouth transmission
Fecal or hand to mouth transmission
Fecal or hand to mouth transmission
Occur in rivers, ponds, lakes, and unfiltered water
N°te: HSU SXSt L>sy contaminants require monitoring under the Assessment Monitoring component of the'
      revised UCMR  EPA is conducting analytical methods development for UCMR (1999) List 2 and List I
      contaminants For more information on the Assessment Monitoring, Screening Surveys, and Pre-Screen Testing
      components of the UCMR, the reader may refer to the proposed UCMR Preamble a^d Rule (64 FR 23398) of
      ins tin
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 UCMR Analytical Methods and Quality Control Manual
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 13.1  UCMR (1999) List 1 Contaminants

 The UCMR (1999) List 1 contaminants and their corresponding required sampling locations, suitable
 EPA analytical methods, and other related analytical details are listed in Table 1.2. There are a total
 of 12 chemical contaminants on the UCMR (1999) List 1. With the exceptions of perchlorate and
 acetochlor, EPA has approved suitable laboratory analytical methods for these contaminants, and
 monitoring is to begin in 2001 under the Assessment Monitoring component of the UCMR Program.
 As mentioned above, EPA plans to approve analytical methods for perchlorate and acetochlor and
 possibly an additional analytical method for nitrobenzene shortly. These methods should be approved
 and ready for use before monitoring is to begin in 2001.
Table 1.2 UCMR (1999) List 1 Contaminants
Contaminants
2,4-Dinitrotoluene
2,6-Dinitrotoluene
4,4'-DDE
Acetochlor
DCPA mono-acid
degradate
DCPA di-acid
degradate
EPTC
Molinate
MTBE
Nitrobenzene
Perchlorate
Terbacil
CAS #
121-14-2
606-20-2
72-55-9
34256-82-1
887-54-7
2136-79-0
759.94.4
2212-67-1
1634-04-4
98-95-3
1497-73-0
5902-51-2
Approved Analytical
Methods
EPA 525.2
EPA 525.2
EPA 508, EPA 508.1,
EPA 525.2, D58 12.96, 990.06
Reserved c
EPA 515.1, EPA 515.2,
D53 17-93, 992.32
EPA 515.1, EPA 515.2,
D53 17-93, 992.32
EPA 507, EPA 525.2,
D5475-93, 991.07
EPA 507, EPA 525.2,
D5475-93, 991.07
EPA 524.2, D5790.95,
SM6210D, SM6200B
EPA 524.2, D5790.95,
SM6210D, SM6200B
Reserved c
EPA 507, EPA 525.2,
D5475-93, 991.07
Minimum
Reporting
Level
2^g/La
2Mg/La
0.8,ug/La
Reserved c
If^gfL"
lMg/La
lMg/La
0.9yUg/La
5Mg/Ld
12,ug/Ld
Reserved c
2,ug/La
Sampling Point
EPTDSb
EPTDSb
EPTDS b
EPTDSb
EPTDS b
EPTDS b
EPTDS b
EPTDS b
EPTDS b
EPTDS b
EPTDS b
EPTDS b
Note: EPA = EPA Methods, D=ASTM Methods, SM = APHA Standard Methods, 900 series = AOAC Methods. See
     Table 1.5 for the full reference for each analytical method.

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    V >™™ReP°rtV1g,L,eve.1(MRL) determined by multiplying by lOthe least sensitivemethod'sminimum detection
    limit (MDL=standard deviation times the Student's T value for 99% confidence level with n-1 degrees offreeSm)
    or when available, multiplying by 5 the least sensitive method's estimated detection limit (EDL^oncentation of
    compound yielding approximately a five to one signal to noise ratio or the calculated MDL, whichever is greater)
    Entry Pomtto the Distribution System. This sample collection location is located atthe entry point after treatment'
    that represents each non-emergency water source in routine use overthe 12-month period of monitoring-  sampling
    must occur at the EPTDS, unless the State has specified other sampling points that are used for tormSce
    monitoring under 40 CFR 141.24(f)(l), (2) and <3). If monitoring at sounfe (raw) water fa^plfng p^iSSs
    detect.onofanyofthecontaminantspntheUCMR(1999)monitoring list, then me system must change Relocation
    of its unregulated contaminant monitoring to the EPTDS.                                      u»u»aon
    To be determined.

    M™ fnf ^ oAerHnn
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 UCMR Analytical Methods and Quality Control Manual
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Contaminant
Linuron
Polonium-210
Prometon
RDX
Terbufos
Aeromonas hydrophtta
CAS #
330-55-2
13981-52-7
1610-18-0
121-82-4
13071-79-9
NAe
Anticipated
Analytical
Methods
SPE/HPLC/UV"
Reserved1"
EPA 525 .2 f
Reserved b
EPA 525.2 f
Reserved b
Minimum
Reporting
Level
Reserved b
Reserved*
Reserved b
Reserved b
Reserved1"
Reserved b
Sampling Point
EPTDSC
Reserved1*
EPTDSC
EPTDSC
EPTDSC
Reserved1"
    Contaminant currently not listed as analyte in this method. Methods under current development in an attempt to
    add this contaminant to the scope of this method. See Table 1.5 for full method reference.
    To be determined.
0   Entry Point to the Distribution System. This sample collection location is located at the entry point, after treatment,
    that represents each non-emergency water source in routine use over the twelve-month period of monitoring;
    sampling must occur at the EPTDS, unless the State has specified other sampling points that are-used for
    compliance monitoring under 40 CFR 141.24(f)(l), (2), and (3).  If monitoring at source (raw) water sampling
    points indicates detection of any of the contaminants on the UCMR (1999) monitoring list, then the system must
    change the location of its unregulated contaminant monitoring to the EPTDS.
    Methods  development currently in progress to develop a solid  phase extraction/gas chromatography/mass
    spectrometry (SPE/GC/MS) method for the determination of this compound.
"   CAS number is Not Applicable.
f   Contaminant listed to be analyzed with this method. However, adequate sample preservation for this contaminant
    is not provided by the procedures for this method. Preservation studies are currently being developed for suitable
    sample preservation for this contaminant.
8   Methods  development currently in progress to  develop a  solid phase extraction/high performance liquid
    chromatography/ultraviolet (SPE/HPLC/UV) method for the determination of this compound.



Listed in Table 1.4 are the UCMR (1999) List 3 contaminants and related sampling and analytical
information.  Completion of method(s) development is not expected prior to  the Assessment
Monitoring or Screening Survey components of the UCMR Program.  Instead, UCMR (1999) List
3 contaminants will be monitored during the Pre-Screen Testing component of the UCMR Program,
most likely to be conducted in 2004.
Table 1.4 UCMR List 3 (1999) Contaminants
Contaminant
Lead-210
Adenoviruses
Caliciviruses
Coxsackieviruses
CAS#
14255-04-0
NAb
NAb
NAb
Anticipated
Analytical
Method
Reserved a
Reserved a
Reserved a
Reserved8
Minimum
Reporting
Level
Reserved3
Reserved "
Reserved a
Reserved2
Anticipated
Sampling
Point
Reserved*
Reserved *
Reserved "
Reserved8

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  UCMR Analytical Methods and Quality Control Manual
                                                                               August 1999
Contaminant
Cyanobacteria (blue green
algae, other freshwater
algae, and their toxins)
Echoviruses
Helicobacter pylori
Microsporidia
CAS#
NAb
NAb
NAb
NAb
========
Anticipated
Analytical
Method
Reserved a
Reserved a
Reserved8
Reserved a
=^=— — — ^— — — __
Minimum
Reporting
Level
Reserved a
Reserved a
Reserved3
Reserved3
========
Anticipated
Sampling
Reserved1
Reserved8
Reserved a
Reserved3
     CAS number is Not Applicable.
  1.4    Analytical Methods for UCMR (1999) List 1 Contaminants

  Table 1 5 includes the UCMR (1999) List 1 contaminants and related analytical methods that are
  required for monitoring under the Assessment Monitoring component of the revised UCMR The
  purpose of the revised UCMR is to obtain contaminant occurrence data in support of nature
  regulatory decisions.  The data required for regulatory decision-making must be of high quality.
  Most analytical methods are subject to some degree of false-negative test results (not detecting an
  contaminant when it is present), false-positive test results (either incorrectly identifying or detecting
  a contaminant, or introducing a contaminant into a sample when it is not present), and errors in the
  accuracy and precision of quantitative results.

  For the UCMR (1999) List 1  contaminants laboratory analyses, EPA has approved the use of
  alternative (i.e., non-EPA) analytical methods of the voluntary consensus standard oiganizations
  (including tiie  ASTM, AOAC, and APHA).  These methods are identified and HsSrSfce
 equivalent EPA method in Table 1.5. Note, however, that whether EPA or one of the altotive
 methods are used, additional quality control measures for UCMR analyses  are required   The
 additional quality control measures are included in the revised UCMR (40 CFR 141 40) and are

 as reSnc'es^r tite^der* ^ f°llowing Sections of this Manua1'EPA ^ethod numbers are used


 The data quality needs of drinking water compliance monitoring data are different compared to the
' SS£?°n   * US£   oc?urrence data- The P^se of compliance monitoring is to determine
 rwSm-   ?? a ?!S5ST?r1^ prelent in ** d™*^ water above the established Maximum
 Contaminant Level (MCL).  Unless the concentration of the contaminant closely approaches the
 T™ ' ev*n'PPre?lse data can be used to assure the data user that the contaminant is not present at
          "        °Ve ^ M?^ In C°ntraSt' *" USefolness of occ^nce data is mSch more
                 F^1810?1 ^ the measurement. The ability to perform valid and meaningful

thepercentage of US. waters which have contaminant X above the minimum reporting level (MRL)

                                         or at "*-concentrations in one

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UCMR Analytical Methods and Quality Control Manual
August 1999
The ability to correctly identify a chemical contaminant is directly related to the type of chemical and
the analytical method used. For example, contaminants such as the disinfection by-products are far
less likely to be misidentified than pesticides or herbicides, because disinfection by-products are
typically present  at  relatively high concentrations hi disinfected waters, while pesticides  and
herbicides are much less likely to be present, or are present at much lower concentrations.  The
analytical method selected will also determine the accuracy of the qualitative identification.  In
general, the most reliable qualitative identifications come from methods which use mass spectral
data for contaminant identification.  However, these  methods are typically  less sensitive than
methods that rely on less selective detectors.
                1                                             n :|'                  '        '
To  ensure that the data collected under this regulation  are of  sufficient quality to meet  the
requirements of these regulatory decisions, EPA is specify ing that only the analytical methods  and
procedures listed hi Table 1.5 be used hi obtaining these data. This Manual explains additional
quality control requirements and contaminant confirmation procedures that are specified in the
regulation. The subsequent sections of this Manual provide an overview of methods, sampling, and
quality control procedures to be used in the UCMR Assessment Monitoring program.  As methods
are approved for perchlorate and acetochlor, EPA will issue a supplement to this Analytical Methods
and Quality Control Manual.  Furthermore, EPA will issue additional supplements to this Manual
as new methods become available for the additional contaminants listed in Tables 1.3 and 1.4.
Table 1,5 Approved Analytical Methods for UCMR (1999) List 1 Contaminants
Chemical Contaminant
CAS#
Volatile Organic Compounds
MTBE
Nitrobenzene
1634-04-4
98-95-3
Methodology
EPA Method
Equivalent Methods

EPA 524.2"
EPA 524.2 "^
D5790-95b;SM6210Dc;
SM6200BC
D5790-95b;SM6210Dc;
SM6200B"
Semivolatile Organic Compounds
2,4-Dinitrotoluene
2,6-Dinitrotoluene
121-14-2
606-20-2
EPA 525 .2 a
EPA 525.2 •
none identified
none identified
Chlorinated Hydrocarbon Pesticides
DDE
72-55-9
EPA 525 .2 a; EPA 508 a;
EPA 508. la
D58 12-96"; 990.06 d
Nitrogen- and Phosphorus-Containing Pesticides
EPIC
Molinate
759-94.4
2212-67-1
EPA 525.2 a; EPA 507 a
EPA 525 . 2 a; EPA 507 a
D5475-93b;991.07d
D5475-93b;991.07d
                                           10

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UCMR Analytical Methods and Quality Control Manual
                                                                                        August 1999
Chemical Contaminant
Terbacil
Acid Herbicides
DCPA mono-acid degradate
DCPA di-acid degradate
CAS#
5902-51-2
Methodology
EPA Method
EPA 525.2 a; EPA 507"

D5475-93b;991.07d

887-54-7
2136-79-0
EPA 515.1 *f; EPA 515.2 ••*
EPA 515.1 lf; EPA 515.2 a-f
D531 7-93 b; 992.32 d
D53 17-93"; 992.32 d
   V    , n,  ,  "I6 ""* "«=u«jus wiiiui you must ronow ror tnis Kule are listed at 40 CFR 141 24 (el
   £""# Book of ASTMStandards, 1996 and 1998, Vol. 11.02, American Society for Testing and Materials  Method
     /Slf^o^f m &*An™alB°°k°t'ASTM Standards, 1998, Vol. 11.02. Methods D5790-95^ D5475-93
   and D5317-93 are located in toe Annual Book of ASTM Standards, 1996 and 1998, Vol 11.02.  Cop£ maybe
   obtoned from the Amencan Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohockenf PA

   ?WR 2?^nf,°nly ^ in thC ?? editiT ^tandard Methods for the Examination of Water and Wastewater,



                                                            ^ff * «— «i- *• *-*^

   SK K°^-°fA^s(sf f^OAC  (Association of Official Analytical Chemist)  International, Sixteenth
   laltimorl MDTl^^^^^                         FirSt Uni°n Nati°nal Bank Lockbox, PO Box 75198,

   Specific recommendations regarding the use of EPA Method 524.2 for measuring nitrobenzene are included in
   Section 6 of this Manual. Note that EPA is currently conducting methods development research to determine if
   m^P^nf.fne is compatible with the preservation requirements of EPA Method 525.2.  If research indicates that
   bPA Method 525.2 is suitable for monitoring nitrobenzene, EPA will issue a public notice and provide for a Dublic
   comment period prior permitting the use of EPA Method 525.2 for measuring nitrobenzene
   Additional recommendations for these methods are listed in Section 6 of this Manual.
                                              11

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VCMR Analytical Methods and Quality Control Manual                                       August 1999
                                              12

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  UCMR Analytical Methods and Quality Control Manual                                   August 1999


  Section 2.  Sampling Plan

  2.1    Monitoring By Public Water Systems

  The focus of the monitoring in the revised UCMR is on occurrence or likely occurrence of
  contaminants in the drinking water of community and non-transient, non-community water systems
  For regulatory purposes, public water systems (PWSs) are categorized as  "community water
  systems," or "non-community water systems".  Community water systems (CWSs) are specifically
  defined as "public water systems which serve at least 15 service connections used by year-round
  residents or regularly serve at least 25 year-round residents," while a non-transient non-community
  water system (NTNCWS) means "a public water system that is not a community water system"
  (40CFR141.2). These non-community systems are available to serve the public, but do not do so
  on a year-round basis in most cases, or do so but are used by people on a temporary basis (e e used
  by people traveling).                                                             "6"'

 PWSs will monitor at the sampling sites and at the sampling frequencies specified in the revised
 UCMR (40 CFR 141.40). EPA or the State will provide further specifications and guidance on the
 monitoring schedule and other requirements to the PWSs. The  subsequent general discussion of
 sampling is for informational purposes only and does not alter  the requirements specified in the
 regulation or in directions from the State or EPA to PWSs.


 2.1.1   Systems Required To Monitor

 Under this program, all CWSs and NTNCWSs serving more than 10,000 people (large systems) are
 required to monitor for unregulated contaminants. However, PWSs that purchase then: water must
 only monitor for UCMR contaminants that must be sampled for in the distribution system (i.e., the
 sampling point is listed as "distribution line"). For systems serving 10,000 or fewer people (small
 systems), only a statistically selected, nationally representative sample of 800 CWSs andNTNCWSs
 must monitor. EPA will pay for the reasonable costs of monitoring for this representative sample
 of small systems.  The State or EPA will notify those systems selected for inclusion in the national
 representative sample.  Transient non-community  water systems will not be included in this
 mnmtnnncr
 monitoring.
From the representative sample of 800 systems, EPA will select 20 to 30 systems to serve as "Index"
systems. Information collected from these systems will provide a broader understanding of small
systems. Index systems must monitor each year during the 5-year UCMR cycle. Data collected from
Index systems will provide information on the effects of seasonal and annual variability  pumping
cycles, and other environmental and program factors that may affect UCMR monitoriAg results
bPA will provide additional guidance and instructions to the Index systems.  EPA will provide
contractor support to collect and ship samples as well as gather additional Index system data.


2.2    Sampling Frequency

?™?l™™n°on?UCt ^ Assessment Monitoring during 1 year of the Assessment Monitoring period
2001 to 2003 (except for the Index systems, which will monitor every year from 2001-2005 as
discussed above). The year of monitoring and the time of sample collection should coincide to the
extent practical, with other scheduled compliance monitoring. For example, a low-vulnerability
                                          13

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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 system that may only monitor for compliance purposes during 1 year in a 3-year period could collect
 its required UCMR samples during that same year. Further, to the extent practical, analyses for the
 UCMR should be coordinated with analyses for other required monitoring using the same methods
 to help reduce costs.

 PWSs using surface water sources, or ground water under the influence of surface water,  must
 sample four times per year for 1 year during the Assessment Monitoring period. One of the sampling
 times must occur between May 1 and July 31, or another period of greatest vulnerability specified
 by the State or EPA. Large PWSs using surface water or ground water under the influence of surface
 water must select either the first, second, or third month of a quarter and sample in that same month
 of each of four consecutive quarters. In other words, systems must monitor under one of the
 following quarterly sampling schedules: January, April, July, October; or February, May, August,
 November; or March, June, September, December. PWSs using ground water sources will sample
 two times per year for 1 year during the Assessment Monitoring period, with one of these sampling
 times occurring between May 1 and July 31, or another period of greatest vulnerability as specified
 by the State or EPA. The second set of samples for ground water systems must be collected 5 to 7
 months before or after the vulnerable period sampling event. For all small PWSs participating hi
 the national representative sample of small systems, the State or EPA will specify the day, plus or
 minus 2 weeks, on which samples must be collected.


 2.3    Sampling Points

 Sampling must be performed at the locations specified in the UCMR Program. The required UCMR
 sampling locations, referred to as sampling points, are contaminant- specific and are summarized in
 Table 1.2 for the UCMR (1999) List 1 contaminants. Possible sampling points for the UCMR
 (1999) List 2 and List 3 contaminants are listed in Tables 1.3 and 1.4, respectively.

 For contaminants on the UCMR (1999) List 1, samples must be collected at entry points to the
 distribution system (EPTDSs) representing each non-emergency water source in routine use over the
 12-month period of monitoring, unless the State has specified other sampling points that are used
 for compliance monitoring under 40 CFR 141.24(f)(l), (2), and (3). Thus UCMR samples may be
 collected from either the EPTDS or from the source (raw) water if the State has specified that source
water sampling points are to be used for standard compliance monitoring. However, if monitoring
at source water sampling points indicates detection of any of the contaminants on the monitoring list,
then the system must shift its unregulated contaminant monitoring to the EPTDS for all future
monitoring under the UCMR, unless the State or EPA determines that no treatment or processing
was in place that would affect the measurement of the contaminants. In that case, the additional.
sampling at the EPTDS would not be required. The requirement for UCMR samples to be collected
at the EPTDS follows the existing regulatory approach and provides data for exposure assessment.
                                          14

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  UCMR Analytical Methods and Quality Control Manual                                   August 1999

  Section 3. Sample Collection and Preservation

  3.1    Chemical Contaminants

  Sample preservation and holding times  for the contaminant-specific  analytical determinative
  methods specified in the UCMR Program are summarized in Tabk 3 . 1 . The sample collection and
  preservation procedures described below must be followed for all samples collected for the UCMR

                   a™* *e Rule spedfies *" resampiing
 3.1.1  Nitrogen- and Phosphorus-Containing Pesticides

 The three UCMR (1999) List 1 nitrogen- and phosphorus-containing pesticides, EPTC2, molinate2
 and terbacil2 may be analyzed with EPA Method 525.2,  EPA Method  507 or the approved
 equivalent methods including ASTM Method D5475-93 or AOAC Method 99 1.07 (see Table 1 5)
 For reference see EPA Method 507  - Determination of Nitrogen- and Phosphorus-Containing
 Pesticides in Water byGasChromatography with a Nitrogen-Phosphorus Detector (Table  1 5)
 (Sampling procedures based on EPA Method 525.2 are described below in Section 3 1 5V Samcle
 procedures based on EPA Method  507,  including sample containers,  chlorine testing
 dechlonnation, and sample collection, preservation, storage, and holding times are described below:

 Sample container - Use one-liter or one-quart amber glass bottles fitted with Teflon-lined screw
 caps Amber bottles are required for the UCMR to protect samples from light. The bottle must be
 washed  and dried as  described in Section 4.1.1 of the EPA Method before use to minimize
 contamination.  Cap liners are cut to fit from sheets (Pierce Catalog No. 012736 or equivalent) and
 extracted with methanol overnight prior to use.

 Residual chlorine determination - If water to be sampled is known or suspected to contain residual
 rnpn^ft6??11111^1011  ^Y61 of ^sidual  chlorine is necessary. Diethyl-p-phenylenediamine
 SnSlf £ rT^ comincsrcialty available and can be used to determine 4 level of residual
 ffrt?S2  *  t   DetTTne *°* record ^ level of residual chlorine in the water to be sampled
 dechlorirSSd      SamP    C°ntamS reSldUaI leV6ls °f cMorine' each samPle ^ need ^ be
SSfate tSr^; To d^rinate f« samPle> add approximately 80 milligrams of sodium
thiosultate per liter of sample to the sample containers prior to filling.  If needed add as much
additional sodium thiosulfate as necessary to eliminate all residual chlorine.
Sample collection - When
and allow the system to ~
""             le "
                but
             ,          ^e  as saze, usuay aout to minutes.
   "°m a ^^ n0t throu«]bl "V P^tic or rubber hoses or tubing. AdjSt
    Stream (ab°Ut ** diameter of a Pencil) "d c«^ct samples from me
usmg.automatlc samplers, use refrigerated glass sample containers if
 ent mCl^ding aut°matic samPlers' must be free of plasti?tubing^Set
each interferin ana                                       &****,
    ote         t                                   '       e ee
and other parts that may leach interfering analytes into the water sample.
      These pesticides are also semi-volatile organic compounds and therefore are also discussed in Section 3. 1 .5


                                         15

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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 Fill the sample bottles until almost full, but take care not to flush out any dechlorination chemicals
 from the sample bottle. After the sample bottle has been filled, close the bottle, invert three or four
 times, and keep the sample bottle sealed until analysis.

 The method specifies the addition of the  biocide mercuric chloride to the sample to retard
 microbiological degradation. Mercuric chloride, however, is being withdrawn because it is highly
 toxic and poses handling and disposal problems. Mercuric chloride should not, therefore, be used
 to preserve samples for the UCMR Program.

 Sample storage - Immediately store the samples at 4°C (±2°) . To do so, place the samples on ice
 or with frozen cold packs in a cooler, or place hi a refrigerator that can maintain the samples at 4°C
 (±2°).  Keep the samples at 4°C (±2°) from the time of collection until extraction.

 Sample holding time - Extract samples within 14 days.  Preservation study results indicated that
 most method contaminants present in samples were stable for 14 days when stored under these
 conditions. The contaminants EPTC and terbacil exhibited recoveries of less than 60% after 14 days;
 consequently, the maximum sample holding time for these contaminants is 14 days.  If samples are
 not extracted within this period, discard and replace the samples.

 Sample extract storage and holding time - Analyze extracts within 14 days. Store extracts at 4°C
 (±2°) away from light. Preservation study results indicate that most contaminants are stable for 28
 days; however, a  14-day maximum extract storage time is recommended.  (See Table 3.1 for a
 summary of holding times.) If samples are not analyzed within the appropriate period, discard and
 replace the samples.


 3.1.2  Chlorinated Hydrocarbon Pesticides

 The UCMR (1999) List 1 chlorinated hydrocarbon pesticide, 4,4'-DDE3, may be analyzed with EPA
 Method 508,508.1,525.2 or the approved equivalent methods, including ASTM Method D5812-96
 and AOAC  Method 990.06 (see Table 1.5).  Sampling procedures based on EPA Method 525.2,
 including sample containers,  chlorine testing  and dechlorination,  and  sample collection,
 preservation, storage, and holding times are described below in Section 3.1.5. Sampling procedures
 based on EPA Methods 508 and 508.1 are described below:

 EPA Method 508 - Determination of Chlorinated Pesticides in Water by GC with an Electron
 Capture Detector (see Table 1.5).

 Sample container - Use one-liter Amber glass bottles fitted with Teflon-lined screw caps.  Amber
bottles are required for the UCMR to protect samples from light. The container must be washed and
 djried before use as described in Section 4.1.1 of the EPA Method to minimize contamination. Cap
liners are cut to fit from sheets (Pierce Catalog No. 012736) and extracted with methanol overnight
prior to use.
              ''!  ' J ' l'          '                '                '' ',  "           •   '    '
Residual chlorine determination - If water to be sampled is known or suspected to contain residual
chlorine, determination of the level of residual chlorine is necessary. Diethyl-p-phenylenediamine
       The pesticide 4,4'-DDE is a semi-volatile organic compound and is therefore also discussed in Section
       3.1.5.

                                           16

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  UCMR Analytical Methods and Quality Control Manual                                   August 1999


  (DPD) test-kits are commercially available and can be used to determine the level of residual
  chlorine in the field. Determine and record the level of residual chlorine hi the water to be sampled
  If the water to be sampled contains residual levels of chlorine, each sample will need to be
  H c*/*V» I *-\**t M Q-f £*A                                                         r
 dechlorinated.
 Sample dechlormation - To dechlorinate the sample, add approximately 80 milligrams of sodium
 thiosulfate per liter of sample to the sample containers prior to filling. If needed, add as much
 additional sodium thiosulfate as necessary to eliminate all residual chlorine.

 Sample collection - When sampling from a water tap, remove any aeration equipment, open the tap
 and allow the system to flush until the water temperature has stabilized, usually about two minutes
 Collect the sample directly from a tap and not through any plastic or rubber hoses or tubing  Adjust
 the flow to a slow but steady stream (about the diameter of a pencil) and collect samples from the
 flowing stream.  When using automatic samplers, use refrigerated glass sample containers  if
 possible.  Sampling equipment, including automatic samplers, must not contain plastic tubing
 gaskets, and other similar parts or materials that may leach chemicals into the sample.

 Fill the sample bottles until almost full, but take care not to flush out any dechlorination chemicals
 from the sample bottle. After the sample has been collected, close the bottle, invert three or four
 times, and keep the sample sealed from collection time until analysis.

 The method specifies the addition of the  biocide mercuric chloride to  the sample to retard
 microbiological degradation. Mercuric chloride, however, is being withdrawn because it is highly
 toxic and poses handling and disposal problems.  Mercuric chloride should not, therefore be used
 to preserve samples for the UCMR Program.

 Sample storage - Immediately store the samples at 4°C (± 2°). To do so, place the samples on ice
 or with frozen cold packs in a cooler, or place in a refrigerator that can maintain the samples at 4°C
 (± 2 ).  Keep the samples at 4°C (± 2°) from the time of collection until analysis.

 Sample holding time - Preservation study results  indicate that most of the target contaminants
 present m the samples are stable for 7 days when  stored under these conditions. Contaminant
 stability may be affected by the  matrix; therefore, the analyst should verify that the preservation
 technique is applicable to the samples under study. (SeeTableS.l for a summary of holding times )
 It samples are not extracted within the appropriate period, discard and replace the samples.

 Sample extract storage and holding time -  Store sample extracts at 4°C (±2°), away from light
 Al 4-day maximum extract storage time is recommended. However, contaminant stability may be
 affected by the matrix;  therefore, the analyst should  verify  appropriate extract holding times
 applicable to the samples under study. If samples are not analyzed within the appropriate period
 discard and replace the samples.                                                          '
^•^th/0JI°£'1 -.Deter^tion°f Chlorinated Pesticides, Herbicides, and Organohalides by
Liquid-Solid Extraction and Electron Capture Gas Chromatography (see Table 1.5).

Sample container - Use one-liter or one-quart amber glass bottles fitted with Teflon-lined screw

         n?fj£* H m fTiref 'fi^thc UCM? because some of *« method contaminants are
        to light and are oxidized or decomposed upon exposure to light
                                          17

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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 Residual chlorine determination - If water to be sampled is known or suspected to contain residual
 chlorine, determination of the level of residual chlorine is necessary. Diethyl-p-phenylenediamine
 (DPD)  test-kits  are commercially available and can be used to determine the level of residual
 chlorine in the field. Determine and record the level of residual chlorine in the water to be sampled.
 If the water to be sampled contains residual levels of chlorine, each sample will need to be
 dechlorinated.

 Sample dechlorination - To dechlorinate the sample, add approximately 80 milligrams of sodium
 sulfite per liter of sample to the sample containers prior to filling. If needed, add as much additional
 sodium sulfite as necessary to eliminate all residual chlorine.

 Sample collection - When sampling from a water tap, remove any aeration equipment, open the tap
 and allow the system to flush until the water temperature has stabilized, usually about two minutes.
 Collect the sample directly from a tap and not through any plastic or rubber hoses or tubing. Adjust
 the flow to a slow but steady stream (about the diameter of a pencil) and collect samples from the
 flowing stream.   When using automatic samplers,  use refrigerated glass sample  containers  if
 possible. Sampling equipment, including automatic samplers, must be free of plastic tubing, gaskets,
 and other parts that may leach interfering analytes into the water sample.

 Fill the sample bottles until almost full, but take care  not to flush out any dechlorination chemicals
 from the sample bottle. After collecting the sample, close the bottle, invert three or four times, and
 wait one minute until preserving the sample with acid.

 Sample preservation - The one minute waiting period after sample collection is crucial; it is
 important to reduce the level of residual chlorine before preserving the sample with acid. If the acid
 is added immediately following  collection, the dechlorination reaction may be incomplete. This
 allows residual free chlorine to oxidize and/or chlorinate PAHs in the sample, including the surrogate
 standard specified by the method. Also, do not directly  mix hydrochloric acid and sodium sulfite
 prior to sampling.

 After waiting one minute, adjust the pH to less than 2 by carefully adding 6 N hydrochloric acid (this
 may require as much as 4 milliliters of acid). This should retard the microbiological degradation of
 the contaminants hi water.  Also, this is the same pH used in the extraction, and is required to
 support the recovery of acidic compounds. Close the  sample bottle, Teflon face down, invert three
 or four times, and keep the sample sealed until analysis.

 Sample storage - Samples must be iced or refrigerated at 4°C (±2°) from the tune of collection until
 extraction. Immediately store the samples at 4°C (±2°). To do so, place the samples on ice or with
 frozen cold packs in a cooler, or place in a refrigerator that can maintain the samples at 4°C  (±2°).
 Keep the samples at 4°C (±2°) from the tune  of collection until analysis.

 Sample holding time - Extract samples within 14 days. Preservation study results show that the
 UCMR contaminants are stable for 14 days in samples that are preserved as described in Sections
 8.2 and 8.3 of the EPA Method. (See Table 3.1 for a summary of holding times.) If samples are not
 extracted within this period, discard and replace the samples.

 Sample extract holding time - Analyze sample extracts within 30 days (refrigerated sample extracts
may be stored up to 30 days prior to analysis).  If sample extracts are not analyzed within this period,
discard and replace the samples.


                                          18

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  UCMR Analytical Methods and Quality Control Manual                                   August 1999
 3.1.3  Acid Herbicides
  The two UCMR (1999) List 1 acid herbicide-based contaminants, the mono- and di-acid degradates
  of dimethyl tetrachloro terephthalate (DCPA), may be analyzed with EPA Method 515 1  EPA
  Method 515.2 or the approved equivalent methods including ASTM Method D5319-93 and AOAC
  Method  992.32  (see Table 1.5).  For reference, see EPA Method 515.1 - Determination of
  Chlorinated Acids in Water by Gas Chromatography -with an Electron Capture Detector or EPA
  Method 515.2 - Determination of Chlorinated Acids in Water Using Liquid-Solid Extraction and
  Gas Chromatography with an Electron Capture Detector (Table 1.5). It is important to note that
  because the approved methods do not allow for the identification and quantification of the individual
  acids, the single  analytical result obtained should be reported as total DCPA mono- and di-acid
  degradates. For specific clarifications concerning the use of EPA Methods 515.1 and 515 2 or their
  approved equivalent methods, please see Section 6.1 of this Manual. Sampling procedures based
  on EPA Methods 515.1 and 515.2, including sample containers, chlorine testing and dechlorination
  and sample collection, preservation, storage and holding times are described below:

  Sample container - If samples are being collected for EPA Method 515.1 or an approved equivalent
 method, use one-liter or one-quart amber glass bottles fitted with Teflon-lined  screw caps  If
 samples are being collected for EPA Method 515.2 or an approved equivalent method use 250
 millihter amber glass bottles fitted with Teflon-lined screw caps.  Amber bottles are being required
 to protect samples from light. The container must be washed and dried as described hi Section 4.1.1
 of the EPA Methods before use to minimize contamination. Cap liners are cut to fit from sheets
 (Pierce Catalog No. 012736) and extracted with methanol overnight prior to use.

 Residual chlorine determination - If water to be sampled is known or suspected to contain residual
 chlorine, determination of the level of residual chlorine is necessary. Diethyl-p-phenylenediamine
 (DPD) test-kits are commercially available and can be used to determine the level of residual
 chlorine in the field. Determine and record the level of residual chlorine in the water to be sampled.
 If the water to be sampled contains  residual levels of chlorine, each  sample will need to be
 dechlorinated.

 Sample dechlorination - To dechlorinate the sample, add approximately 80 milligrams of sodium
 thiosulfate per liter of sample to the sample container prior to filling.  If needed, add as much
 additional sodium thiosulfate as necessary to eliminate all residual chlorine.

 Sample collection - When sampling from a water tap, remove any aeration equipment, open the tap
 and allow the system to flush until the water temperature has stabilized, usually about two minutes
 Collect the sample directly from a tap and not through any plastic or rubber hoses or tubing  Adjust
 the flow to a slow but steady stream (about the diameter of a pencil) and collect samples from the
 flowing stream   When using automatic samplers, use refrigerated glass sample containers if
 possible. Sampling equipment, including automatic samplers, must be free of plastic tubing gaskets
 and other parts that may leach interfering analytes into the water sample.

 Fill the sample bottles until almost full, but take care not to flush out any dechlorination chemicals
 from the sample bottle. After collecting the sample, close the sample bottle,  invert three or four
 times, and keep the sample bottle sealed until analysis.

 The method specifies the addition  of the  biocide mercuric chloride to the sample to retard
microbiological degradation. Mercuric chloride, however, is being withdrawn because it is highly
                                          19

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 UCMR Analytical Method and Quality Control Manual                                  August 1999


 toxic and poses handling and disposal problems. Mercuric chloride should not, therefore, be used
 to preserve samples for the UCMR Program.

 Sample preservation procedures in EPA Method 515.2 are similar to those listed hi EPA Method
 515.1, with the exception samples collected for EPA Method 515.2 must be acidified via the addition
 of 6 N HC1. If samples are being collected for EPA Method 515.2, be sure to wait one minute after
 dechlorinating the sample before preserving it with acid to ensure that the dechlorination reaction
 is complete.

 Sample storage - Immediately store the samples at 4°C (±2°) . To do so, place the samples on ice
 or with frozen cold packs in a cooler, or place in a refrigerator that can maintain the samples at 4°C
 (±2°). Keep the samples at 4°C (±2°) from the time of collection until extraction.

 Sample holding time - Extract samples within 14 days. However, contaminant stability will very
 likely be affected by the matrix; therefore, the analyst should verify that the preservation technique
 is applicable to the samples under study. Preservation study results from EPA Method 515.1 indicate
 that the contaminants (measured as total acid) present in samples are stable for 14 days when stored
 under these conditions. Preservation study results for EPA Method 515.2 indicate mat the sample
 contaminants (measured as total acid) are  stable in water for 14 days when stored under these
 conditions.  If samples are not extracted within the appropriate period, discard and replace the
 samples.

 Sample extract storage and holding time - Store extracts at 4°C (±2°) away from light. Analyze
 extracts within 28 days,  according to EPA Method 515.1 and 14 days according to EPA Method
 515.2. However, the analyst should verify that appropriate extract holding times are applicable to
 the samples under study. Preservation study results indicate that most contaminants are stable for
 28 days according to EPA Method 515.1 and 14 days according to EPA Method 515.2. (See Table
 3.1 for a summary of holding times.) If samples are not extracted within the appropriate period,
 discard and replace the samples.


 3.1.4  Volatile Organic Compounds

 The two UCMR (1999) List 1 volatile organic compounds (VOCs) monitored under the revised
 UCMR Program, methyl tertiary-butyl ether (MTBE) and nitrobenzene, may be analyzed with EPA
 Method 524.2 or an approved equivalent method, such as ASTM Method D5790-95 or APHA
 (Standard Methods) SM621OD or SM6200B (see Table 1.5). For reference, see EPA Method 524.2 -
 Measurement  of Purgeable Organic  Compounds in  Water by  Capillary  Column  Gas
 Chromatography/Mass Spectrometry, or an approved equivalent method. It is important to keep the
 sample bottles in an area known to be free of VOCs prior to sample collection. General sampling
 procedures based  on EPA Method 524.2,   including sample containers,  chlorine testing,
 dechlorination, sample collection, sample preservation, storage and holding times, are described
 below. For specific analytical method recommendations pertaining to the use of EPA Method 524.2
 for measuring nitrobenzene, please see Section 6.2 of this Manual.  The sampling requirements
 detailed hi EPA Method 524.2 must also be followed when using any of the approved equivalent
methods.

Sample containers - Use 40-milliliter to 120-milliliter screw cap glass vials, each equipped with
a Teflon-faced silicon septum. To prepare sample bottles: wash vials and septa with detergent and


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  UCMR Analytical Methods and Quality Control Manual                                   August 1999


  rinse with distilled water; air dry the vials and septa at room temperature; place in a 105°C oven for
  one hour; then remove and allow to cool in an area known to be free of organics.

  Residual chlorine determination - If water to be sampled is known or suspected to contain residual
  25?^'determmation of me level of residual chlorine is necessary. Diethyl-p-phenylenediamine
  (DPD) test-kits are commercially  available and can be used to determine the  level of residual
  chlorine in the field.  Determine and record the level of residual chlorine in the water to be sampled
  If the water to be sampled contains residual  levels of chlorine, each sample will  need to be
  nf^r-n \rvnrm+c*A                                                         *•
dechlorinated.
 Sample dechlorination - To dechlonnate the sample, add approximately 25 milligrams ascorbic
 acid (or 3 milligrams sodium thiosulfate4) per 40 milliliter of sample volume to sample container
 prior to collecting the sample. If necessary to eliminate all residual chlorine, add an additional 25
 milligrams ascorbic acid (or 3 milligrams sodium thiosulfate) per each 5 milligrams per liter residual
 chlorine in the sample.

 Sample collection - Collect all samples in duplicate or triplicate. When sampling from a water tap
 remove any aeration equipment, open the tap and allow the system to flush until the water
 temperature has stabilized, usually about two minutes. Collect the sample directly from a tap and
 not through any plastic or rubber hoses or tubing. Adjust 'the flow from the tap to a slow but steady
 stream (about the diameter of a pencil) and collect the sample from the flowing stream When using
 automatic samplers, use refrigerated glass sample  containers, if possible.  Sampling equipment,
 including automatic samplers, must not contain plastic tubing,  gaskets, and other similar parts or
 materials that may leach chemicals into the sample.

 Fill sample to almost overflowing, but take care not to flush out any dechlorination chemicals that
 are in the sample bottle. Do not let air bubbles pass through the sample as the sample bottle is filled,
 and, when sealed, the sample bottle must contain no air bubbles. After the sample bottle has been
 filled, close the bottle and invert three or four times,  and then wait one minute before preserving the
 sample with acid.                                                             •      &

 Sample preservation - The one-minute waiting period after sample collection is  crucial- it is
 important to reduce the residual chlorine before preserving the sample with acid. If the acid is added
 immediately following sample collection, the dechlorination reaction may be incomplete.

 After one minute adjust the pH to less than 2 by carefully adding two drops of 1:1 hydrochloric acid
 for every 40 milliliters of sample.  (The hydrochloric acid preservation reduces sample pH in order
 to retard microbiological degradation of the contaminants being analyzed.)  Ensure that no air
 bubbles are trapped in the completely full sample bottle. Close the sample bottle, Teflon face down
 and invert three or four times. Keep the sample bottle sealed from collection time until analysis.'

 Sample storage - Immediately store the samples at 4°C (± 2°). To do so, place the samples on ice
?1 ™   r?Zen ,  d packs m a cooler'or Place in a refrigerator that can maintain the samples at 4°C
(± 2 ).  Keep the samples at  4°C (± 2°) from the time of collection until analysis,  the sample
storage area must be free of organic solvent vapors,  excess heat and direct light
       Because neither MTBE nor nitrobenzene boil below 25°C, sodium thiosulfate may be used to reduce
       residual chlorine.


                                          21

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UCMR Analytical Methods and Quality Control Manual                                   August 1999


Sample holding time - Analyze all samples within 14 days of collection (see Table 3.1  for a
summary of holding times).  If samples are not analyzed within this period, discard and replace the
samples.


3.1.5  Semi-volatile Organic Compounds

The six5  UCMR (1999) List  1  semi-volatile  organic  compounds, 2,4-dinitrotoluene, 2,6-
dinitrotoluene, 4,4'- DDE , s-ethyl-dipropylthiocarbamate (EPTC)7, molinate7, and terbacil7, may be
analyzed with EPA Method 525.2 or the approved equivalent methods including ASTM Methods
D5812-96 and D5475-93, or AOAC Methods 990.06 or 991.07. Note that two of these semi-volatile
organic compounds (2,4-dinitrotoluene and 2,6-dinitrotoluene) can be analyzed with only the EPA
approved analytical method; there are no approved equivalent methods for these two contaminants.
See Table 1.5 for a listing of the approved equivalent analytical methods for each contaminant. For
reference, see EPA Method 525.2 - Determination of Organic Compounds in Drinking Water by
Liquid-Solid Extraction and Capillary Column Gas Chromatography/Mass Spectrometry, or an
approved equivalent method. General sampling procedures based on EPA Method 525.2, including
sample containers, chlorine testing and dechlorination, and sample collection, preservation, storage,
and holding times, are described below:

Sample containers - Use one-liter or one-quart amber glass bottles fitted with Teflon-lined screw
caps. Amber bottles are required for the UCMR because some of the method contaminants are very
sensitive to light and are oxidized or decomposed upon exposure to light. It is important to keep the
sample bottles in an area known to be free of volatile and semi-volatile organic compounds prior to
sample collection.

Residual chlorine determination - If water to be sampled is known or suspected to contain residual
chlorine, determination of the level of residual chlorine is necessary. Diethyl-p-phenylenediamine
(DPD) test-kits are commercially available and can be used to determine the level of residual
chlorine in the field. Determine and record the level of residual chlorine in the water to be sampled.
If the water to be sampled contains residual levels of chlorine, each sample will need to be
dechlorinated.

Sample dechlorination - To dechlorinate the sample, add approximately 40-50 milligrams of
sodium sulfite to sample container prior to collecting the sample.  If needed, add as much sodium
sulfite as necessary to eliminate all residual chlorine.
       It is anticipated that acetochlor and possibly nitrobenzene will be added to the scope of this method once
       further methods development research has been completed. If EPA Method 525.2 and the equivalent
       voluntary consensus standards are approved for measuring acetochlor and nitrobenzene, a supplement to
       this Manual will be issued.

       This semi-volatile organic compound is a pesticide and is specifically identified and listed as a chlorinated
       pesticide in Table 1.5.

       These three semi-volatile organic compounds are pesticides and are specifically identified and listed as
       nitrogen/phosphorus pesticides in Table 1.5.


                                            22

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  UCMR Analytical Methods and Quality Control Manual                                  August 1999
fSlnwl^f? " T1?1 T^K. fr°m a Water tep' remove ** aeration equipment, open the tap
and allow the system to flush until the water temperature has stabilized, usually about two minute?

S n™ % samPle directly froma tap and not through any plastic or mbber hoses ombTgAdjusi


^nlefrn0111^ fl P * * 2™ ^2^ ^^ (ab°Ut ^ After ^ Sample b°ttle has been filled' close ft6 bottle
 four times, and then wait one minute before preserving the sample with acid.
 SimTPle P1?6"??0? "The one-minute waiting period after sample collection is crucial to reduce

 the level of residual chlorine before preserving the sample with acid.  If the acid is added

 immediately following collection, the dechlorination reaction may be incomplete  This allows

 residualfree chlonne tooxidize and/or chlorinate poly-aromatic hydrocarbons^AHs) in m^sS

 h^tC^th8^011 13-2\of *e Method) including the internalLd surrogate s^didfjeS

 bLS r^in^?^ °£** degradation/oxidation of the internal standards, calculated resulte

 hSrlS?  ? ™? standard recovery can be erroneously elevated.  Also, do not directly nix
 hydrochloric acid and sodium sulfite prior to sampling.                       w uireouy mix




 After waiting one minute, adjust the pH to less than2by carefully adding 6 N hydrochloric acid (this

 may require as much as 4 millihters of acid). This should retard the microbiological degradation^

 Ae contaminants in water  Also, this is the same pH used in the extractionfand is reared to

 support the recovery of acidic compounds. Close the sample bottle, Teflon face down, invert three

 or four times, and keep the sample sealed until analysis.
 ?r Sfr    ge - Imnfdl.ately st?re ^ samples at 4°C (± 2°). To do so, place the samples on ice

 or with frozen cold packs in a cooler or place in a refrigerator that can maintain the samples at 4°C


 £eJ muSh?^ TP  S ^ 4 C (± -2 } fr°m ^ time °f collection until analysis. Sample storage
 area must be free of organic contaminants, excess heat, and direct light.
             f oSj " ?rtract1flie If11?168 ^n 14 days of sample collection and analyze the

              30 days of sample collection. Results of the holding time and storage studv of dl

method contammants showed that most are stable for 14 days in wSer samples wS?sa^nles

are dechonnated preserved, and stored as described above.  (See Table 31 for 1 smim^? of

holding times.) If samples are not analyzed within this period, discard and replie ti
                                         23

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 UCMR Analytical Methods and Quality Control Manual
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Table 3.1 Preservation and Holding Times for Approved Analytical Methods
Method(s)
EPA 507
D5475-93
991.07
EPA 508
D58 12-96
990.06
EPA 508.1
D58 12-96
990.06
EPA 515.1
D53 17-93
992.32
EPA 5 15.2
D53 17-93
992.32
EPA 524.2
D5790-95
SM6210D
SM6200B
EPA 525.2
Preservation
Sodium
thiosulfate;
Cool 4°C; Dark
Sodium
thiosulfate;
Cool 4°C; Dark
Sodium sulfite;
6NHCl-pH<2;'
Cool 4°C
Sodium
thiosulfate;
Cool 4°C; Dark
Sodium
thiosulfate;
6NHCl-pH<2;
Cool 4°C; Dark
Ascorbic acid or
Sodium
thiosulfate;
l:lHCl-pH<2;
Cool 4°C
Sodium sulfite;
6 N HC1 - pH < 2;
Cool 4°C; Dark
Sample
Holding
Time
14 days
7 days
14 days
14 days
14 days
14 days
14 days
Extract
Holding
Time
14 days
(4°C, Dark)
14 days
(4°C, Dark)
30 days
28 days
(4°C, Dark)
14 days
(4°C, Dark)
N/A
30 days
from
collection
Sample Size
1L
1L
1L
1L
250 mL
40 - 120 mL
1L
Container
Amber Glass
with Teflon-
lined Cap
Amber Glass
with Teflon-
lined Cap
Amber Glass
with Teflon-
lined Cap
Amber Glass
with Teflon-
lined Cap-
Amber Glass
with Teflon-
lined Cap
Glass with
Teflon-lined
Septum
Amber glass
with Teflon-
lined Cap
Note: EPA = EPA Methods, D = ASTM Methods, SM = APHA Standard Methods, 900 series = AOAC Methods. See
     Table 1.5 for the full reference for each analytical method.
3.2    Monitoring of Routine Water Quality Parameters

In addition to the requirement that systems monitor for UCMR contaminants, the revised UCMR
also specifies that certain chemical and physical parameters must be measured in the field at each
sampling point from which UCMR samples are collected. These parameters are being required
because they are important indicators of water quality and may contribute to the likelihood of the
contaminants being found in drinking water.  EPA believes that these parameters will allow for a
more thorough scientific understanding of the occurrence of unregulated contaminants. As all
UCMR (1999) List 1 contaminants are chemicals, EPA is only  requiring that the pH of the water
being sampled is measured and reported.  For UCMR (1999) List 2 and List 3 contaminants, some
of which are microbiological in nature, monitoring of additional water quality parameters such as
                                           24

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UCMR Analytical Methods and Quality Control Manual
                                                                                       August 1999
temperature, total disinfectant residual, etc., may be required. The analytical methods approved for
measuring pH are included in Table 3.2 below.
Table 3.2 Water Quality Parameters to be Monitored with UCMR (1999) List 1
Contaminants
Parameter
pH
Contaminant
Type
Chemical
Methodology
EPA
Method
150.1"
150.2"
Standard
Methods
4500-H* Bb
Other
ASTMD1293-84C
ASTMD 1293-95°
   ~,f^o~m.~~i~ ~.™ —"'". **v "•""""«- "v/ui uu uirrt, r»E,rvju, Z.D-W. Martin Luther King Dr., Cincinnati Ohio
   non  «  u 'Toot1031 m.e,thods «* also in "Methods for Chemical Analysis of Water and Wastes," EPA-600/4-79-
   020, March 1983, available from the National Technical Information Service (NTIS)  U S Department of
   Commerce, 5285 Port Royal Rd., Springfield, Virginia 22161, PB84-128677. The NTIS to 1-free number is (800)
           ^nn1?^ Editions of Standard Methods for the Examination of Water and Wastewater, 1992 and 1995
   Method 4500-ir B can also be found in the 20^ Edition Standard Methods for the Examination of Water and
   Wastewater,^* American Public Health Association, 1015 Fifteenth St. NW, Washington, DC, 20005
   Annual Book ofASTM Standards, Editions 1994 and 1996,Volumes 11.01, American Society for Testing and
   Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428. Version D1293-84 is located in the Annual
   BookofASTMStandards,l994, Volumes  11.01.  Version D1293-95  is located in the Annual Book ofASTM
   Standards, 1996, Volumes 11.01.                                                            J
                                             25

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UCMR Analytical Methods and Quality Control Manual                                      August 1999
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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 Section 4. Sample Transport

 Immediately after sample collection place all UCMR samples on ice or with frozen cold packs in an
 insulated container, cooler, or place in a refrigerator to cool the samples to 4°C (±2°)  Keep the
 samples at 4°C (±2°) from the time of collection until analysis, including during any necessary
 transport.  Do not let any samples freeze. If transporting samples to an off-site laboratory pack
 samples in insulated containers or coolers carefully to protect against sample bottle breakage during
 transport.  Samples are commonly transported to off-site laboratories via laboratory pick-up service
 delivery by the water system's own personnel, or delivery with a commercial courier service.

 Transport the appropriately cooled [i.e., 4°C (±2°)] and packed samples to the analytical laboratory
 as soon as possible after sample collection. Transporting the samples within 2 days of sample
 collection is strongly recommended; transporting the samples immediately—the same day of sample
 collection—is advised. Note that samples must be packed with sufficient ice or frozen cold packs
to ensure that samples are maintained at 4°C (± 2°) during the entire transport period, but do not let
any samples freeze. All samples must be processed by the laboratory within 7 to 14 days of sample
collection; therefore, provide adequate time for sample pick-up, transport, delivery, extraction and
analysis.  Immediate (sample collection day) transport  of samples to the laboratory will ensure
adequate sample analysis time and will greatly reduce the chance that systems will need to re-collect
samples due to late samples exceeding holding tunes.
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UCMR Analytical Methods and Quality Control Manual                                      August 1999
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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 Section 5.  UCMR Quality Control Requirements

 Several quality control (QC) methods required for UCMR monitoring by EPA are methods currently
 required  and in use under other SDWA regulations.  As a result, mechanisms for reviewing
 laboratory qualifications are already hi place for determination of other chemical contaminants
 determined by these methods.  Laboratories that provide data to the EPA in support of the UCMR
 must document that they are currently approved by a State and that they have State certification
 and/or approval  to perform those analyses  using UCMR-specified methods.  Additionally,
 laboratories  must  also complete  and document  initial  demonstration  of capability  for all
 contaminants requiring monitoring by UCMR-specified methods.

 UCMR Assessment Monitoring must be conducted only using the analytical methods specified in
 the UCMR (see Table 1.5). The QC procedures specified in these approved analytical methods as
 well as additional QC procedures identified in this Manual must be followed to ensure accurate and
 precise data.

 QC procedures and the frequency of QC testing vary among the methods.  Many of the methods
 specified  m the  UCMR provide criteria  to  be used  in  evaluating and accepting laboratory
 performance based on related QC data. This section describes the various QC procedures EPA
 requires as part of the UCMR and the rationale for acceptance criteria.  Because EPA cannot accept
 monitoring data if the applicable QC requirements are not met, laboratories must strictly adhere to
 the QC described in this section. The following will cause monitoring data to be excluded from the
 database:

        •   failure to use the correct calibration check standard concentration

        •   failure to verify the calibration curve at the specified frequency

        •   failure to meet the acceptance criteria for verifying calibration

       •  contaminants detected hi the laboratory reagent (method) blank at concentrations equal
          to or more than one-half the minimum reporting level (MRL)

       •  when applicable, failure to meet the acceptance criteria for the internal standard

       •  when applicable, failure to meet the acceptance criteria for the surrogate standard

       •  failure to analyze samples and/or extracts within the specified holding times

Certain QC data must also be reported as part of the analytical services performed for the UCMR
 Inese data are being collected  to evaluate the quality of the monitoring data.  These reporting
requirements are noted hi the reporting elements hi Section 7 of this Manual
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 UCMR Analytical Methods and Quality Control Manual
August 1999
 5.1    Minimum Reporting Level

 The minimum reporting level (MRL) concentrations  listed in Table 5.1 were determined by
 multiplying by 10 the least sensitive method's minimum detection limit (MDIA8 or, when available,
 multiplying by 5 the least sensitive method's estimated detection limit (EDL). The MRL for VOCs
 was determined by multiplying by  10 either the published MDL or 0.5 micrograms per liter,
 whichever is greater.  The MDL of 0.5 micrograms per liter  (0.0005 milligrams per liter)  was
 selected to conform to the VOC MDL requirements of 40 CFR 141.24(f)(17)(i)(E).
Table 5.1 UCMR Methods and Minimum Reporting Levels
Contaminant
2,4-Dinitrotoluene
2,6-DinitrotoIuene
4,4'-DDE
Acetochlor
DCPA mono- and di-
acid degradates .
EPTC
Molinate
MTBE
Nitrobenzene
Perchlorate
Terbacil
Approved UCMR Analytical Methods
EPA 525.2
EPA 525.2
EPA 508; EPA 508.1; EPA 525.2; D58 12.96;
990.06
Reserved b
EPA 515.1; EPA 515.2; D5317-93; 992.32
EPA 507; EPA 525.2; D5475-93; 991.07
EPA 507; EPA 525.2; D5475-93; 991.07
EPA 524.2; D5790.95; SM6210D; SM6200B
EPA 524.2; D5790.95; SM6210D; SM6200B
Reserved1"
EPA 507; EPA 525.2; D5475-93; 991 .07
Minimum Reporting
Level
2,ug/La
2yUg/L'
0.8 /zg/L a -
Reserved15
lUg/L*
l,"g/La
0.9^g/La
5//g/Lc
12,ug/Lc
Reserved1"
2Mg/La
Note: EPA - EPA Methods, D=ASTM Methods, SM=APHA Standard Methods, 900 series = AOAC Methods. See
      Table 1.5 for the full reference for each analytical method.

'   Minimum reporting level (MRL) determined by multiplying by 10 the least sensitive method's minimum detection
    limit (MDL=standard deviation times the Student's t value for 99% confidence level with n-1 degrees of freedom),
    or when available, multiplying by 5 the least sensitive method's estimated detection limit (EDL=concentration of
    compound yielding approximately a five to one signal to noise ratio or the calculated MDL, whichever is greater).
b   To be determined.
       The MDL equals the standard deviation times the Student's t value for 99% confidence level with n-1
       degrees of freedom.


       The EDL equals the concentration of compound yielding approximately a five to one signal to noise ratio
       or the calculated MDL, whichever is greater.
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 UCMR Analytical Methods and Quality Control Manual                                    August 1999


 c   MRL for VOCs determined by multiplying by 10 either the published MDL or 0.5 yug/L, whichever is greater. The
     MDL of 0.5 //g/L (0.0005  mg/L) was selected to conform to the VOC  MDL requirements of 40 CFR
     141.24(f)( 17)(i)(E)-


 Laboratories must demonstrate that they can achieve reliable data at the MRL for each contaminant.
 Therefore, the calibration curve must encompass the MRL concentration. The laboratory must verify
 the accuracy of the curve at the MRL by analyzing a calibration check standard at the MRL
 concentration (see Section 5.2 of this Manual).

 EPA recognizes that some laboratories are able to provide reliable data at concentrations lower than
 those  shown hi Table 5.1. To achieve consistency in the National Drinking Water Contaminant
. Occurrence  Database (NCOD), laboratories are only required to report quantitative results for
 concentrations equal to or greater than the MRLs. However, EPA also recognizes the usefulness of
 receiving more complete results to allow evaluation of the analytical method implementation.
 Systems and laboratory that are able to reliably report results below the MRL are encouraged to do
 so.  To report reliable results obtained below the MRL, laboratories and/or water systems should do
 three things:

        1)  For data element  6, Analytical Results - Sign, report a "<," indicating that the result
           obtained is less than the MRL listed in Table 5.1.                            .

       2)  For data element  7, Analytical Result - Value, report the  actual concentration value
           obtained for the contaminant.

       3)  For data element 17, Presence/Absence, report the contaminant as "Present."

 The combination of these three steps will allow for the reporting of data below the MRL, and will
 enable EPA to more fully evaluate the MRL for the respective contaminant and assist in determining
what the final MRL might be if EPA requires future monitoring of the contaminant.


5.2    Calibration

Each method describes calibration procedures that are used to determine the concentrations of the
method contaminants. Some  methods allow several options:

       •   a calibration curve based on either external standards  or detector responses to the
           contaminant relative to an internal standard

       •   an average response factor for each contaminant

The laboratory must select and follow one of the calibration procedures outlined in the approved
method to meet the requirements of the UCMR. In addition, the mass spectral (MS) methods, EPA
Methods 524.2 and 525.2, have specific tuning criteria that must be met prior to performing the
calibration procedure.

All methods specified in the UCMR require that calibration span the expected concentration range
of the  samples being analyzed.   The number of calibration  standards  necessary to meet this


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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 requirement varies from three to six, depending on the method.  The UCMR does not require
 laboratories to change method calibration procedures with the exception that the low level standard
 must be at  or below the MRL specified for each contaminant, and the mid-level standard must
 simply be near the midpoint of the calibration range.


 5.2.1  Calibration Verification

 Complete calibration curves are not required on  a daily basis.  However, the analyst must
 periodically verify calibration during sample analysis to ensure accuracy of the analytical results.
 The frequency at which calibration must be checked varies according to the analytical method used.
 Frequency requirements for verifying calibration have been established by EPA to meet the accuracy
 requirements for the UCMR and are presented in Table 5.2.

 Most of the methods recommend checking the instrument calibration using a mid-level calibration
 check standard. The method acceptance  criteria for verifying calibration are based on this standard.
 However, to meet the objectives of the UCMR,  calibration must be verified across the range of
 contaminant concentrations that are being measured. Based on the recommendations from technical
 experts experienced with these methods, EPA is specifying calibration verification at low- and mid-
 levels for each method.

 The frequency of verifying calibration  for UCMR  samples is based  on the number of samples
 analyzed together in an analysis batch. For Assessment Monitoring, an analysis batch is defined as
 samples analyzed using the same instrument within a 24-hour period. However, the maximum
 number of UCMR samples that can be included in one analysis batch is 30.  The 24-hour period
 begins with the analysis of the low-level  calibration check standard and it ends with the analysis of
 the final calibration check standard. The 24-hour period does not necessarily include the analysis
 time used to generate the calibration curve. However, if a new curve is prepared each time samples
 are analyzed, the"24-hour period still begins with the analysis of the low-level calibration check
 standard.

 When determining the 30 sample maximum, do not count method blanks, shipping blanks, initial
 and continuing calibration check standards, matrix spikes (MSs), matrix spike duplicates (MSDs),
 and any independent QC samples that are analyzed with the UCMR samples.

 Analysis of the low-level calibration check standard must be completed prior to analysis of any
 samples; each contaminant must meet the acceptance criteria provided  in Table 5.3. If the criteria
 cannot be met, identify and eliminate the source  of the problem, then perform a new instrument
 calibration according to the method calibration procedures.

 It is important to note that an acceptable end calibration check standard must be analyzed before
 analyses of other samples (i.e., non-UCMR samples) may begin.  Thus, if the last five samples
 analyzed were part of the UCMR, the analyst must perform an acceptable end calibration check
 standard before starting non-UCMR analyses.

For all methods, after analyses of no more than 10 UCMR samples, the calibration curve must be
verified using either a low- or mid-level continuing calibration check standard; each contaminant
must meet the acceptance criteria listed in Table 5.3 or 5.4. If the criteria are not met, reanalyze all
samples or extracts that were analyzed between this standard and the last standard meeting


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UCMR Analytical Methods and Quality Control Manual
                                                                               August 1999
acceptance criteria for the problem contaminant(s) after the calibration problem is resolved If the
samples or extracts cannot be re-analyzed, then the data for the problem contaminants) are
considered invalid for those samples and should not be reported to EPA
Table 5.2 Frequency Requirements for Verifying Calibration |
Methods
EPA 507
D5475-93
991.07
EPA 508
D58 12-96
990.06
EPA 508.1
D58 12-96
992.32
EPA 515.1
D53 17-93
992.32
EPA 5 15.2
D53 17-93
992.32
EPA 524.2
D5790-95
SM6210D
SM6200B
EPA 525.2
Method
Specifications
each working day
each working day
each 12 hour shift
each working day
each working shift
every 12 hours
every 12 hours
UCMR Specifications |
Initial
each batch of 30
samples or daily
(whichever is more
frequent)
Continuing
alternate between low- and
mid-level standard after
every 10 samples
NOtC: TSle=lE5Pf0r1h?n?n' ?f= ^ ^i?^ ?M = ApHA Standard Methods, 900 series = AOAC Methods. See
lable 1 .5 tor the full reference for each analytical method.
Table 5.3   UCMR Low-Level Calibration Check Standard Concentrations and
            Acceptance Criteria
            Contaminant
2,4-dinitrotoluene
  Concentration of
Low-Level Standard
                                                           
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UCMR Analytical Methods and Quality Control Manual
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Contaminant
Acetochlor
DCPA mono- and di-acid degradates
EPTC
Molinate
MTBE
Nitrobenzene
Perchlorate
Terbacil
MRL(Aig/L)
Reserved a
Mg/L
ll*SfL
0.9 ^g/L
5^g/L
12^g/L
Reserved3
2/^g/L
Concentration of
Low-Level Standard
Reserved a
^MRL
^MRL
<;MRL
^MRL
sMRL
Reserved8
sMRL
Acceptance
Criteria
Reserved"
±40%
± 40 %
±40%
± 40 %
± 40 %
Reserved a
± 40 %
   To be determined.
Table 5.4 Mid-Level Calibration Check Standard Concentrations and Acceptance
Criteria
Contaminant
2,4-dinitrotoIuene
2,6-dinitrotoluene
4,4'-DDE
Acetochlor
DCPA mono- and di-acid degradates
EPTC
Molinate
MTBE
Nitrobenzene
Perchlorate
Terbacil
Mid-Level Standard
middle of calibration range
middle of calibration range
middle of calibration range
Reserved3
middle of calibration range
middle of calibration range
middle of calibration range
middle of calibration range
middle of calibration range
Reserved3
middle of calibration range
Acceptance
Criteria
± 20 %
± 20 %
± 20 %
Reserved a
± 20 %
± 20 %
± 20 %
± 20 %
±20%
Reserved8
± 20 %
 lo be determined.
                                              34

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  UCMR Analytical Methods and Quality Control Manual                                   August 1999


  5.3    Method Detection Limit

  The method detection limit (MDL) is defined as the minimum concentration of a substance that can
  be measured and reported with 99% confidence that the contaminant concentration is greater than
  zero. Usually, measurements at the MDL concentration are considered qualitative, because they are
  not precise enough to meet the needs of the data user. If accurate and precise data are required, do
  not report below the level at which the necessary precision and accuracy are achieved.

  Laboratories must calculate meir MDLs for each analysis (using the primary column) according to
  the procedure in CFR § 1 3 6 Appendix B (included in this Manual as Appendix C), with the following
  additional requirements:                                                                &

        •  Include all sample processing steps in the determination.  Conduct extractions and
           analyses over at least 3 days.

        •  Select a spiking concentration which is less than or equal to the established MRL for
           each contaminant monitored by the UCMR.  Analyze a total of seven duplicates of
           reagent water spiked at a concentration less than or equal to the established MRL as
           listed in Table 5.1.  From the data collected from these analyses, calculate measurement
           accuracy.  Each data point must be within ±50% of the value of the spiked solution
           concentration.

        •  Calculate the MDL for each contaminant according to the formula listed in CFR § 1 36
           Appendix B (included in this Manual as Appendix C). Do not subtract the blank value
           as suggested in the procedure.

        •  To ensure the accuracy of data reported for the UCMR, laboratory calculated MDL levels
           for each contaminant must be less than or equal to one-half of the MRL listed in Table



 5.4   Laboratory Reagent (Method) Blank
                *  apProved 5>r the UCMR «q«ire periodic analysis of a laboratory reagent
         blank. For all methods, a method blank is defined as an aliquot of reagent water that is
S±*iefCHy f & T*1516' includinS exP°sure to an glassware, equipment, solvents, reagents,
internal standards, and surrogates that are used with other samples. This blank is used to determine
it method contaminants or other interferences are present in the laboratory environment, the reagents
or trie 3pp3T2,tu.s.                                                                        *

The frequency of the method blank analysis depends on the type of sample manipulation required
SSL ?  f mS^n?£   f dyu S'  Methods ** involve «tawtian «f the sample usually stipulate
SS2JJ  A ?  ?.    ^ 71* 6aC? **?f Samples ** m extracted together  When the samples
are analyzed directly, a blank is analyzed on a daily basis.

The required frequencies for analyzing method blanks for the UCMR are listed in Table 5 5  To

Z^fffT8 °f *£ UCM?' ^alyZC *" method blank <» ** first samPle ^ the insu4en°
rS^t?   £ f°"™mgl!eimt^
carry tiie method blank through the extraction process. Each extraction batch of samples must
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UCMR Analytical Methods and Quality Control Manual
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An extraction batch is defined as all samples prepared/extracted together by the same person(s)
during a work day (normally an 8-10 hour period for routine working schedules). Use the same lot
of extracting solvent, internal standard spiking solution, and surrogate standard spiking solution for
all samples included in a batch. When applicable, derivatize all samples in an extraction batch with
the same batch of derivatizhig agent.  Include a maximum of 20 UCMR samples in an extraction
batch.  When detennining the 20 sample maximum, do not count method blanks, shipping blanks,
calibration check standards, any independent QC samples, duplicate samples, and spiked samples
that are extracted with UCMR samples.

While some methods state that background interferences should be below the MDL, the general goal
for all methods approved for the UCMR is to ensure that the background levels are low enough to
not interfere  with an accurate measurement.  If any of the method analytes are detected at a
concentration equal to or greater than one-half the MRLs (see Table 5.6), then perform no further
analyses until the source of the problem is identified and eliminated. If the source is traced to any
material that was used in the preparation of the set of samples to be analyzed, then discard all these
prepared samples (or extracts) and repeat the preparation procedure using another aliquot of each
sample. If the samples cannot be re-extracted, then consider all data for the problem contaminant(s)
invalid for all samples in the extraction or analysis batch, as appropriate, and flag the monitoring data
as not meeting QC criteria. Data not meeting UCMR QC criteria should not be reported to EPA.

Contamination problems in the extraction process cannot be detected until the analysis step. If a
problem is discovered, then the data for one or more contaminants in all the samples in the extraction
batch are lost unless the laboratory has a back-up aliquot of each sample which can be extracted.
EPA limited the extraction batch to 20 UCMR samples to minimize the number of samples that
could be potentially lost because of a contamination problem. More than one batch of samples may
be extracted within a day.

Laboratories  should be aware of the potential for  carry-over between  samples when highly
contaminated samples are analyzed.  To avoid this, laboratories may find that additional blanks are
needed to "rinse" the system after high concentration samples are analyzed. If blanks are analyzed
for this purpose, the laboratory is not required to report data from these analyses.
Table 5.5 Frequency Requirements for Analyzing Laboratory Reagent (Method)
Blanks
Method
EPA 507
D5475-93
991.07
EPA 508
D58 12-96
990.06
EPA 508.1
D58 12-96
992.32
Method Specifications
1 per sample set or if reagents changed
1 per sample set or if reagents changed
1 per sample set per 12 hour shift
UCMR Specifications
1 per sample batch (^20 samples)
1 per sample batch (^20 samples)
1 per sample batch (^20 samples)
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UCMR Analytical Methods and Quality Control Manual
                                                                                     August 1999
Method
EPA 5 15.1
D53 17-93
992.32
EPA 5 15.2
D53 17-93
992.32
EPA 524.2
D5790-95
SM6210D
SM6200B
EPA 525.2
Method Specifications
1 per sample set
1 per sample set
each batch or 1 per 20 samples
every 12 hour extraction batch
UCMR Specifications
1 per sample batch (^20 samples)
1 per sample batch (^20 samples)
1 per sample batch (^20 samples)
1 per sample batch (<;20 samples)
wow: tfA - bPA Methods, D - ASTM Methods, SM = APHA Standard Methods, 900 series = AOAC Methods See
Table 1.5 for the foil reference for each analytical method.
Table 5.6 UCMR Acceptance Criteria for Laboratory Reagent (Method) Blanks
Contaminant
2,4-Dinitrotoluene
2,6-Dinitrotoluene
4,4'-DDE
Acetochlor
DCPA mono- and di-acid
degradates
EPTC
Molinate
MTBE
Nitrobenzene
Perchlorate
Terbacil
===== _ ===
Minimum Reporting Level
2/^gfL
2/^g/L
0.8£ig/L
Reserved a
lA
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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 5.4.1  Field Reagent Blank (Shipping or Travel Blank)

 EPA Method 524.2 and the approved equivalent methods are the only methods specified in the
 UCMR that requires the preparation and analysis of a field reagent blank (sometimes referred to as
 a shipping or travel blank) with each group of samples collected from the same general sample site
 at approximately the same time. This blank is an aliquot of reagent water or other blank matrix that
 is placed in a sample container in the laboratory and treated as a sample in all respects, including
 shipment to the sampling site, storage, preservation, and all analytical procedures. The purpose of
 this blank is to determine if method contaminants or other interferences are present in the field or
 shipping environment. If any of the contaminants are detected at concentrations equal to or greater
 than one half the MRL, consider all data for the problem contaminant(s) for all samples in the
 shipping batch invalid and flag the monitoring data as not meeting QC criteria. Data not meeting
 UCMR QC criteria should not be reported to EPA.


 5.5    Quality Control Sample

 Most of the UCMR methods recommend that the laboratory analyze a quality control (QC) sample
 at least quarterly. A QC sample is a solution of method contaminants of known concentration which
 is used to spike an aliquot of reagent water or sample matrix.  Obtain the QC sample from a source
 external to the laboratory and different from the source of calibration standards. Use the analysis of
 the spiked sample it to check laboratory performance.


 5.6    Sample Matrix Spike and Matrix Spike Duplicate

 One technique that is useful in evaluating a laboratory's precision and accuracy for a method is to
 determine the precision and accuracy of duplicate analyses. To do this, a sample is divided into two
 or more aliquots in the laboratory,  and is processed and analyzed as two separate samples.  This
 technique is only useful when the original sample contains background concentrations of the method
 contaminants.

 To effectively evaluate precision for UCMR contaminants, the EPA is requiring preparation and
 analysis of a sample matrix spike (MS) and matrix spike duplicate (MSD). A laboratory-spiked MS
 sample is an aliquot of an environmental sample to which known  quantities of the method
 contaminants are added ha the laboratory. A laboratory MSD sample is an additional aliquot of that
 same environmental sample to which the same known quantities of the method contaminants are
 added in the laboratory. For the purposes of the UCMR, EPA is not requiring that the standards used
to spike the MS/MSD samples be obtained from a second source. Analyze these MS/MSD samples
 exactly like a typical monitoring sample; the purpose is to determine whether the sample matrix
 contributes bias to the analytical results. Determine the concentrations of the contaminants in the
unspiked sample matrix hi a separate aliquot.

Laboratories are required to prepare and analyze MS/MSD samples at the frequencies listed in Table
5.7.  Laboratories are required to perform MS/MSD sample analyses on a minimum of 5% of the
UCMR samples that are processed together.  For methods that involve extractions, divide one sample
from each extraction batch into two aliquots (one MS, one MSD), and spike each with a known
concentration of the contaminants prior to extraction. Carry the entire set of unspiked sample and
MS/MSD samples through the entire extraction and analysis process. For methods that do not
involve extractions and for analysis batches of 20 or less, spike and analyze two aliquots of one of


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 UCMR Analytical Methods and Quality Control Manual
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 the UCMR samples in the batch. If the analysis batch contains more than 20 UCMR samples, then
 divide, spike, and analyze two samples.

 Note: As described earlier, an extraction batch is defined as all samples prepared/extracted together
 by the same person(s) during a work day.  Therefore, use the same lot of extracting solvent, internal
 standard spiking solution, and surrogate standard spiking solution for all samples included hi a batch.
 When applicable, derivatize all samples hi a batch with the same batch of derivatizing agent. Include
 a maximum of 20 UCMR samples in an extraction batch. Additionally, an analysis batch is defined
 as samples analyzed within a 24-hour period with 30 as the maximum number of samples that can
 be included in one analysis batch.
Table 5.7 Requirements for Performing Spiked Sample Analyses
Method
EPA 507
D5475-93
991.07
EPA 508
D58 12-96
990.06
EPA 508.1
D58 12-96
992.32
EPA 515.1
D53 17-93
992.32
EPA 5 15.2
D53 17-93
992.32
EPA 524.2
D5790-95
SM6210D
SM6200B
EPA 525.2
Method Specifications
1 per 20 samples or each sample set
whichever is greater
1 per 10 samples or each sample set
whichever is greater
1 per sample matrix
1 per 10 samples or each sample set
whichever is greater
1 per 10 samples or each sample set
whichever is greater
Not required unless matrix effects
suspected
1 per extraction batch 1 per 20 samples
UCMR Specifications
MS/MSD per 20 samples or a batch,
whichever is smaller; alternate low-
mid-level
MS/MSD per 20 samples or a batch,
whichever is smaller; alternate low-
mid-level
MS/MSD per 20 samples or a batch,
whichever is smaller; alternate low-
mid-level .
MS/MSD per 20 samples or a batch,
whichever is smaller; alternate low-
mid-level
MS/MSD per 20 samples or a batch,
whichever is smaller; alternate low-
mid-level
MS/MSD per 20 samples or a batch,
whichever is smaller; alternate low-
mid-level
MS/MSD per 20 samples or a batch,
whichever is smaller; alternate low-
mid-level
	 ±;:   —*-»"«'««'«•»,*•'  ^-iuijYi iriwuiuua, jivi — rt.rn.rt. ouuiuoru meuioas, 5/uu series = AUAv_. Metnoas see
     Table 1.5 for the full reference for each analytical method.


The laboratory must choose a spiking concentration from one of the two concentrations listed in
Table 5.8. The spiking concentration should be within ± 20% of one of the levels provided hi the
table. To determine precision data from laboratory MS/MSD samples at the MRL level and at a
higher concentration, spike the samples at the concentrations listed in approximately a 50% ratio.
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 UCMR Analytical Methods and Quality Control Manual                                   August 1999


 For example, if a set of 40 samples are received, spike two aliquots of a sample from the first 20
 samples with the low-level (± 20 % MRL) spike, and spike the MS/MSD for the second set of 20
 samples with the mid-level spike.

 Laboratories must report all MS/MSD sample recovery data and all data from the batch of samples
 processed/analyzed with the MS/MSD sample. In addition, laboratories must also report the spiking
 concentration for all MS/MSD samples. To facilitate this, data element 16, Spiking Concentration,
 has been included in the data elements required for the UCMR. Values for this data element should
 only be reported for MS/MSD samples, and the unit of measure for the value reported should match
 the unit of measure used to report the sample analytical result reported in data element 7, Analytical
 Result - Value (this unit of measure is reported in data element 8, Analytical Result - Unit of
 Measure).  Data from MS/MSD samples will  be  used by EPA to evaluate the quality of the
 monitoring data.  Water systems  and laboratories may also use these  data to determine the
 appropriateness of the methodology used to analyze the UCMR samples.

 EPA plans to use the data  from MS/MSD analyses to provide an estimate of the precision and
 accuracy of measurements  made by individual laboratories. Subsets of the UCMR data may be
 selected for specific modeling  or correlational  analyses, based on laboratory precision for the
 contaminants of interest. Laboratories  will not  be required to meet specific percent recovery or
 precision requirements for the MS/MSD analyses. Monitoring data will not be rejected based on
 MS/MSD sample recovery  data.
The precision of measurements will be evaluated on the basis of values reported for data element 1 4,
Analytical Precision.  For the  UCMR, analytical  precision is defined as the relative percent
difference (RPD) between MS and MSD results. For each analytical result obtained, the laboratories
and/or systems must report the RPD for the MS/MSD set analyzed in the same batch of samples as
the analytical result being reported. Analytical precision is calculated using the formula:

                                          \r\~r->\
                                 RPD =  ' ]  2I x 100
     RPD = Relative Percent Difference
     r,   = matrix spike (MS) analytical result
     r2   = matrix spike duplicate (MSD) analytical result


EPA will also be evaluating the analytical accuracy of measurements reported by examining the
values reported for data element 15, Analytical Accuracy. Analytical accuracy describes how close
a result is to the true value, and is measured through the use of spikes, standards, surrogates or
performance evaluation samples.  For the purposes of the UCMR, analytical accuracy is defined as
the percent recovery of the contaminant hi the MS sample analyzed in the same analytical batch as
the sample result being reported.  To calculate the analytical accuracy, laboratories should use the
formula:
                                                r.-r,
                           Percent Recovery = —-—— jc 100
                                                  s
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 UCMR Analytical Methods and Quality Control Manual
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      r,    = matrix spike (MS) analytical result
      r3    = sample analytical result
      s    = spiking concentration of matrix spike
Table 5.8 Concentrations for Spiking MS/MSD Samples
Contaminant
2,4-Dinitrotoluene
2,6-Dinitrotoluene
4,4'-DDE
Acetochlor
DCPA mono- and di-acid
degradates
EPIC
Molinate
MTBE
Nitrobenzene
Perchlorate
Terbacil
Low-Level Spike
Concentration
2>ug/L±20%
2(j.g/L±2Q%
0.8,ug/L±20%
Reserved3
1 Mg/L±20%
Ijug/L±20%
0.9^g/L±20%
SAig/L±20%
12,wg/L±20%
Reserved a
2^g/L±20%
Mid-Level Spike
Concentration
± 20% of mid-level standard
± 20% of mid-level standard
± 20% of mid-level standard
Reserved a
± 20% of mid-level standard
± 20% of mid-level standard
± 20% of mid-level standard
± 20% of mid-level standard
± 20% of mid-level standard
Reserved a
± 20% of mid-level standard
5.7    Internal Standard

Several of the UCMR methods require or recommend the use of an internal standard (IS) for
calibration and quantification purposes.  An IS is a pure contaminant that is added to a sample or
sample extract hi a known amount. It is used to measure the relative responses of other method
contaminants and surrogates that are components  of 'the same  solution.  The IS must  be a
contaminant that is not a sample component. When used, the IS is added to all samples, standards,
and QC samples or their extracts.

The methods usually recommend specific compounds and concentrations for use as ISs. When the
method provides flexibility in the selection of the IS or IS concentration, EPA allows the same
flexibility for analyses of UCMR samples.
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  UCMR Analytical Methods and Quality Control Manual
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 The methods vary in their specifications of when the IS is added during the sample processing steps.
 Some methods require the addition of the IS to the sample prior to any processing, while other
 methods stipulate the addition to the sample extract immediately prior to instrumental analysis.
 .Laboratories are required to follow the directions in the method when performing analyses for the
 UCMR.
Table 5.9 Requirements for Internal Standard Analyses
Method
Method Specifications
UCMR
Specifications
UCMR
Acceptance
Criteria
GC Criteria for Sample Extract IS Response
EPA 507
D5475-93
991.07
EPA 508
D58 12-96
990.06
EPA 508.1
D5812-96
992.32
EPA 515.1
D53 17-93
992.32
EPA 5 15.2
D53 17-93
992.32

EPA 524.2
D5790-95
SM6210D
SM6200B
EPA 525.2
< 30% deviation from daily calibration
check standard's IS response
<: 30% deviation from daily calibration
check standard's IS response
± 30% of continuing calibration check
standard or± 50% of initial calibration
:£ 30% deviation from daily calibration
check standard's IS response
£ 30% deviation from daily calibration
check standard's IS response
Same as
method
Same as
method
GC/MS Criteria for IS Response in Continuing Calibration
IS response must not have decreased by
more than 30% of last continuing
calibration or increased by more than 50%
of initial calibration
IS response must not have decreased by
more than 30% of last continuing
calibration or increased by more than 50%
of initial calibration
Same as
method
Same as
method
Note: EPA = EPA Methods, D = ASTM Methods, SM = APHA Standard Methods, 900 series = AOAC Methods See
Table 1.5 for the full reference for each analytical method.
The methods also vary in the criteria used to evaluate the IS recovery, when IS techniques are
utilized.  In general, monitor the detector response to the IS in each sample; it should be relatively
constant during the period in which a batch of samples is analyzed. Specific criteria for evaluating
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  UCMR Analytical Methods and Quality Control Manual                                    August 1999


  the IS responses are listed in the methods and summarized in Table 5.9. Compare each sample's IS
  detector response to the average IS detector response obtained for the calibration curve  The
  acceptance criteria are given as percentage recovery which is determined using the followine
  formula:                                                                              6


          75" % Recovery  = 	SamPle IS Det^or Response	^ m
                           Calibration  Curve Average IS Detector Response


 If the IS in a specific sample does not meet the acceptance criteria specified in the method then
 consider data from that sample analysis invalid.  If possible, re-analyze the sample. If this cannot
 be done, then the data for that sample are considered invalid for the analysis and should not be
 reported to EPA.


 5.8    Surrogate Standard

 Several of the UCMR methods require the use of surrogate analytes.  A surrogate is a pure analyte
 which is extremely unlikely to be found in any sample. It is added to a sample aliquot in a known
 amount before the sample is processed, and is measured with the same procedures used to measure
 other sample target contaminants.  The purpose of a surrogate  analyte is to monitor method
 performance with each sample. When used, the surrogate is added to all samples, standards and QC
 samples.

 The methods usually recommend specific compounds and concentrations for use as surrogate
 standards. When the method provides flexibility in the selection of the surrogate standard or its
 concentration, EPA allows the same flexibility for analyses of UCMR samples.

 Table 5.10 lists the UCMR methods that require surrogates as well as percent recovery acceptance
 criteria where specified by the appropriate methods.

 For EPA Methods 524.2 and 525.2, the surrogate criteria are listed in Section 10.2.6.1 of each
 method.

 There are two techniques for monitoring the surrogate standard. If the method specifies that the
 same concentration of surrogate standard must be added to all samples, standards and QC samples
 then compare the surrogate detector response in each analysis to the average surrogate detector
 response obtained for the calibration curve. The acceptance criteriaare given aspercentaze recovery
 which is determined usine the follnwinafhrrrmla-                         ^       &        *
which is determined using the following formula:


                         	Sample Su,	

                         Calibration Curve Average Surrogate Detector Response
 Surrogate  % Recovery  =          Sample Surrogate Detector Response	^
Some methods recommend preparing a calibration curve for the surrogate standard similar to the
preparation of a curve for each of the method contaminants. In those cases, the acceptance criteria
are given as percentage recovery which is determined using the following formula-
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 VCMR Analytical Methods and Quality Control Manual
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 Surrogate % Recovery '=
                                     Measured Surrogate Concentration
                                     Expected Surrogate Concentration
 x 100
 If the surrogate in a specific sample does not meet the acceptance criteria, re-analyze the sample if
 possible. If this cannot be done, then the data for that sample are considered suspect for the analysis
 hi question, and should not be reported to EPA.

 EPA recognizes that failure to meet the surrogate standard recovery criteria could be the result of
 matrix interferences hi a small number of instances.  Even if this is the reason for failure, the data
 are suspect for all the contaminants in the analysis.
Table 5.10 Requirements for Surrogate Standard Analyses
Method
EPA 507
D5475-93
991.07
EPA 508
D5812-96
990.06
EPA 508.1
D58 12-96
992.32
EPA 515.1
D53 17-93
992.32
EPA 5 15.2
D53 17-93
992.32
EPA 524.2
D5790-95
SM6210D
SM6200B
EPA 525.2
Method Specified
Surrogate Recovery
± 30%
± 30%
± 30%
± 30%
± 40%
± 30%
± 30%
UCMR
Specifications
Same as method
UCMR
Acceptance Criteria
Same as method
Note: EPA = EPA Methods, D = ASTM Methods, SM = APHA Standard Methods, 900 series = AOAC Methods. See
     Table L5 for the full reference for each analytical method.
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  UCMR Analytical Methods and Quality Control Manual                                   August 1999


  5.9    Confirmation

  5.9.1   Gas Chromatographic Methods

  Preliminary identification of contaminant compounds using EPA Methods 507, 508  508 15151
  and 515.2, as well as in the approved alternative methods (see Table  1.5), is performed by
  comparison of the target contaminant retention time to the retention time of a standard reference
  chromatogram.  If the retention time of an unknown contaminant corresponds, within standard
  acceptable limits, to the retention time of a standard reference compound, then identification is
 presumed positive. The UCMR requires analytical confirmation by gas chromatographic/mass
 spectrometry (GC/MS) of positive identification, either using results of the primary column alone
 or with the added secondary column information.

 The length of the retention time window used to make identifications  should be based  on
 measurements of actual retention time variations of standards over the course of a day. A suggested
 window size for a particular contaminant can be calculated using three times the standard deviation
 of a retention time for that particular contaminant. However, the experience of the analyst should
 weigh heavily in the interpretation of chromatograms.

 Identification  requires  expert  judgement  when  sample  components  are  not  resolved
 chromatographically. When peaks obviously represent more than one sample contaminant (i e a
 broadened peak with shoulder[s] or a valley between two or more maxima), or any time when doubt
 exists over the identification of a peak on a chromatogram, use appropriate alternative techniques
 to help confirm peak identification. Positive identification of contaminants is required for results
 by GC/MS. False positives can be minimized by the use of a second dissimilar chromatography
 column. Primary columns and suggested alternative dissimilar confirmation columns are described
 in each of the methods. GC/MS analysis for confirmation is not necessary if positive results from
 the primary column are not confirmed by the secondary dissimilar column.


 5.9.2  Gas Chromatography/Mass Spectrometry Confirmation

 The UCMR  requires  confirmation of any contaminant  detected  above the MRL by Gas
 Chromatography/Mass Spectrometry (GC/MS) methods. Laboratories have the option of confirming
 ?£&r?cencei     analyte using a second chromatography column prior to submitting the sample for
 CrC/MS analyses or may go directly from the primary column analyses to GC/MS confirmation  If
 u G£??^mant detectlon 1S confirmed by the secondary column, then reconfirm the contaminant
 by GC/Mb using three specified ion peaks for contaminant identification. Recommended ion peaks
S3" ld^fication purposes a*6listed in Table 5-H- The UCMR allows single point calibration of
the CrC/MS system for confirmation purposes only as long as the calibration standard is at a
concentration within ± 50% of the concentration determined by the initial analysis. As an option,
laboratories may prefer to perform a three-point calibration with single point daily calibration
verification of the GC/MS system regardless of whether that verification standard concentration is
within ± 50% of sample response. If GC/MS analysis confirms the initial contaminant detection
report the results determined from the initial analysis
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 UCMR Analytical Methods and Quality Control Manual
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Table 5.11 Recommended Confirmation Ions
Contaminant
2,4-dinitrotoluene
2,6-dinitrotoluene
4,4'-DDE
Acetochlor
DCPA dimethyl ester
EPTC
Molinate
MTBE
Nitrobenzene
Perchlorate
Terbacil
Recommended Confirmation Ions
63,
63,
246,
89, 165
89, 165
316,318
Reserved8
299,
86,
83,
41
51,
300, 302
128, 189
126, 187
, 57, 73
77, 123
Reserved3
116,
160, 161
Note: These ions are recommended for use in confirming all positive results. However, since mass spectrometers using
      different mass selection techniques may display spectra with different mass intensities, the analyst may to choose
      alternate ions that better characterize the spectra displayed by their mass spectrometer.

1   To be determined.
5.9.3  Mass Spectrometry Methods

Perform identification and confirmation of a contaminant using EPA Methods 524.2 and 525.2 by
comparison of the contaminant's mass spectrum (after background subtraction) to a reference
spectrum hi the user-created database. For the DCPA degradates, confirm the identification by
injecting the extract obtained during the primary analyses into a mass spectrometer  The  GC
retention time of the contaminant should be within three standard deviations of the mean retention
time of the reference contaminant in the calibration mixture.

In general, all ions that are present above  10% relative abundance in the mass spectrum of the
standard should be present in the mass spectrum of the sample and should agree within ±20%.  For
example, if an ion has a relative abundance of 30% in the standard spectrum, its abundance in the-
sample (contaminant) spectrum should be in the range of 10-50%.  Some ions, particularly the
molecular ions, are of special importance and  should be evaluated even if they are below 10%
relative abundance.

Identification  requires   expert  judgment  when  sample  contaminants  are  not  resolved
chromatographically and produce mass spectra containing ions that are contributed by more than one
contaminant. When GC peaks obviously represent more than one sample  contaminant (i.e., a
ht*rt5lHp*rl^H riAQLT IXnTh Orl/MllHoiMO I SVt* O 1?o110Yr lta
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 UCMR Analytical Methods and Quality Control Manual
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 apparent for two or more contaminants), the identification criteria can be met, but each contaminant
 spectrum will contain extraneous ions contributed by the co-eluting contaminants.  Because
 purgeable organic compounds (such as those for some UCMR contaminants) are relatively small
 molecules and produce comparatively simple mass spectra, this is not a significant problem for most
 contaminants determined according to EPA Method 524.2.

 Structural isomers that produce very similar mass spectra can be explicitly identified only if they
 have sufficiently different GC or retention tunes. Acceptable resolution is achieved if the height of
 the valley between two peaks is less than 25% of the average height of the two peaks.  Otherwise,
 structural isomers are identified as isomeric parrs.


 5.10   Additional Quality Controls

 The laboratory must examine the samples when they arrive in the laboratory to determine if the
 proper shipping procedures were used and the required shipping conditions were maintained.
 Samples requiring storage at 4°C (± 2°) should arrive at the laboratory packed in ice or frozen cold
 packs. If there is no visible ice or the cold packs are completely thawed, the laboratory should report
 the conditions to the water system.  Samples should riot be analyzed if they were not shipped
 properly and/or if they did not arrive in the required condition.  As the UCMR specifies that
 resampling is required within 14 days of the observance of a sampling error, the laboratory should
 immediately contact the water system and arrange for resampling.  If resampling cannot be
 performed within this time period, then the water system should indicate in the report to EPA that
 the samples were invalidated because of a shipment problem and no data should be reported.

 The laboratory also must invalidate samples that were collected in improper sampling containers
 (e.g., plastic bottles instead of glass) or that were improperly filled (e.g.,  half-filled  bottles for
 samples that are required to be completely full). As above, the laboratory should immediately
 contact the water system and arrange for resampling within the'required 14 days.  If resampling
 cannot be performed within this tune period, then the water system should indicate in the report to
 EPA that the samples were invalidated because of a sampling error and no data should be reported.

Finally, the laboratory must ensure each sample is analyzed within the required holding time. A list
of applicable holding times is presented in Table 5.12.  When appropriate, EPA standardized the
holding times across analytical methods for the same contaminant group.
Table 5.12 Maximum Holding Times for Samples and Extracts
Approved Analytical Methods
EPA 507
D5475-93
991.07
EPA 508
D58 12-96
990.06
Sample
14 days
7 days
Extract
14 days
14 days
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 UCMR Analytical Methods and Quality Control Manual
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Approved Analytical Methods
EPA 508.1
D58 12-96
992.32
EPA 515.1
D53 17-93
992.32
EPA 5 15.2
D53 17-93
992.32
EPA 524.2
D5790-95
SM6210D
SM6200B
EPA 525.2
Sample
14 days
14 days
14 days
14 days
14 days
Extract
30 days
28 days
14 days
Not Applicable
30 days from collection
Note: EPA = EPA Methods, D = ASTM Methods, SM=APHA Standard Methods, 900 series=AOAC Methods See
     Table 1.5 for the full reference for each analytical method.
If a UCMR sample is not extracted or analyzed within the times specified in Table 5.12, then the data
for the sample should not be reported.  The laboratory should indicate to the water system that the
sample was invalidated because of a holding time problem. This information would then be reported
to EPA when the system submits its report for that sampling period.
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 Section 6.  Additional Analytical Method Specifications


 6.1    Clarifications Concerning EPA Methods 515.1 and 515.2 and the Approved Equivalent
       Methods

 EPA Methods 5 1 5' 1 and 5 1 5'2' ^ wel1 ^ t*16*1" equivalent voluntary consensus standards (D53 1 7-93
 and 992 32) have been approved for use in measuring the DCPA mono- and di-acid degradates
 under the UCMR (see Table 1.5).  However, EPA is specifically requiring that the methylene
 CS^rdf^h hsted m Sectlons 1L1-4 and 11.1.5 of the EPA Methods (Sections 12.1 4 and 12 1 5
 ?  ? ^Z~93 ^ Section F(a) of 992-32) be performed. The use of this wash is being emphasized
 in the QC requirements because it washes away the parent compound, DCPA.

 If this wash is not performed, the data generated will reflect not just the total of the mono- and di-
 acid degradates of DCPA, but will include the concentration of the parent compound in addition to
 the concentration of the two degradates. As noted previously, because the approved methods do not
 allow for die identification and quantification of the individual acids, the single analytical result
 obtained from these methods should be reported as total DCPA mono- and di-acid degradates.


 6.2   Recommendations for EPA Method 524.2 and the Approved Equivalent Methods
™™™  ^PA is n0t alterinS to method specifications for EPA Method 524.2 for use with the
UCMR, EPA emphasizes that laboratories should use the three stage trap listed in Section 6 2 2 of
the Method [Section 7.2.2. 1 of D5790.95, Section 3 of SM62 1 OD, and Section 2(a)(2) of SM6200B1
Alternate traps may not be capable of retaining adequate concentrations of nitrobenzene, therefore
nitrobenzene can not be detected at reasonable concentrations in either standards or samples  Thus'
the data generated for nitrobenzene with this method will not be capable of meeting the strict quality
control requirements specified in the UCMR and in this Manual
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 Section 7. Reporting


 7.1    Public Water Systems Reporting to EPA

 The appropriate and consistent reporting of UCMR monitoring data from the participating Public
 Water Systems (PWSs) is  critical to EPA's efforts to evaluate the data for future regulatory
 development. The UCMR monitoring data are reported according to specific "data elements"
 through the Safe Drinking Water Information System/Federal Information System (SDWIS/FED)
 for inclusion in the NCOD.

 The PWSs are required to report the UCMR monitoring data to EPA for evaluation. The UCMR
 contaminant occurrence data will be included in the NCOD and will be made available to the public.
 For a detailed description of reporting responsibilities and requirements, refer to the Unregulated
 Contaminant Monitoring Regulation Reporting Guidance, the Unregulated Contaminant Monitoring
 Regulation Guidance for Operators of Public Water Systems Serving 10,000 or Fewer People, and
 the Unregulated Contaminant Monitoring Regulation Integrated Guidance Document, all available
 from the EPA Water Docket, telephone (202) 260-3027, Docket Number W-98-02.

 Monitoring data  for all contaminants must be reported according to contaminant type and must
 include 17 specific data elements for each contaminant. The required data elements are listed in
 Table 7.1. Many of the data elements will be furnished by the laboratory to the PWS and the PWS
 will provide the  remainder of the data elements. A brief definition of each data element is also
 included.  PWSs  can arrange to have laboratories report analytical data directly to EPA. However,
 the PWSs retain final responsibility to ensure that all monitoring data is reported.  In this regard, the
 final reporting responsibility of the PWS is the same as for SDWA compliance monitoring.

 The required data elements will help to optimize the utility and quality of UCMR analytical data.
 The reporting of the data elements listed in Table 7.1 is important to provide  details needed to
 evaluate possible regulatory development related to UCMR contaminants and methods.


 7.1.1   Reporting of Results Obtained for the DCPA Mono- and Di-Acid Degradates

 The analytical methods approved under the UCMR for measuring the DCPA mono- and di-acid
 degradates do not, as approved, allow for the identification and quantification of the individual acids.
 To provide for the consistent reporting of results to the NCOD and to avoid confusion, EPA is
 specifying that the single analytical result obtained from these methods should be reported as total
 DCPA mono- and di-acid degradates. As a result, data element 5, Contaminant/Parameter, will not
 have as acceptable values "DCPA mono-acid degradate" or "DCPA di-acid degradate." Instead, the
 appropriate acceptable value for this data element will  be "Total  DCPA mono- and di-acid
 degradates."


 7.1.2  Reporting of Data Below the Specified Minimum Reporting Level

As previously mentioned in Section 5.1 of this Manual, EPA recognizes that some laboratories are
able to provide reliable data at concentrations lower than the MRLs specified in the UCMR.  To
achieve consistency in the NCOD, laboratories are only required to report quantitative  results for
concentrations equal to or greater than the MRLs. However, EPA also recognizes the usefulness of


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 UCMR Analytical Methods and Quality Control Manual                                   August 1999

 receiving more complete results to allow evaluation of the analytical method implementation.
 Systems and laboratory that are able to reliably report results below the MRL are encouraged to do
 so. To report reliable results obtained below the MRL, laboratories and/or water systems should do
 three things:

        1)  For data element 6, Analytical Results - Sign, report a "<," indicating that the result
           obtained is less than the MRL listed in Table 5.1.

        2)  For data element 7, Analytical Result - Value, report the actual concentration value
           obtained for the contaminant.

        3)  For data element 17, Presence/Absence, report the contaminant as "Present."

 The combination of these three steps will allow for the reporting of data below the MRL, and will
 enable EPA to more fully evaluate the MRL for the respective contaminant and assist in determining
 what the final MRL might be if EPA requires future monitoring of the contaminant.
                                                          i

              ;"    i                             '           •        .
 7.13   Reporting of Water Quality Parameter Data

 As mentioned in Section 3.2 of this Manual, the revised UCMR specifies that certain chemical and
 physical parameters must be measured in the field at each sampling point from which UCMR
 samples are collected. These parameters are being required because they are important indicators
 of water quality and may contribute to the likelihood of the contaminants being found in drinking
 water. EPA believes that these parameters will allow for a more thorough scientific understanding
 of the occurrence  of unregulated contaminants.  As  all  UCMR (1999) List 1 contaminants are
 chemicals, EPA is only requiring that the pH of the water being sampled is measured and reported.
 The pH of the water being sampled must be reported along with other UCMR (1999) List 1 data.
 To facilitate this reporting, data element 5, Contaminant/Parameter, will have "pH" as an acceptable
 value.


 7.2    Public Notification of Results (Report of PWS to Consumers)

 The results of UCMR monitoring will be reportable through the Consumer Confidence Reports
 (CCR), as required by  SDWA §1441(c)(4)(B) and the  Consumer Confidence Reports (CCR)
 regulation (63 FR 44512), as well as through the revised Public Notification Rule (PNR) proposed
 on May 13,1999 (64 FR 25964) and expected to be finalized by late 1999. It is anticipated that
 reporting through the PNR and CCR rules would satisfy the notification provision for unregulated
 contaminants. Failure to monitor for unregulated contaminants required through the UCMR would
 be reportable' under the PNR.

 The results reported through the PNR and CCR rules should be based on the same monitoring data
 EPA and the States will receive. UCMR data will be submitted to SDWIS/FED for inclusion in the
NCOD. Information in the NCOD will be available to the public.

Reporting of unregulated contaminants not on the UCMR (1999) List is not required by EPA under
the CCR or PNR, except as directed by the State. Therefore, any "emerging" contaminants of local
or State concern alternatively could be reported voluntarily to the NCOD.  This reporting would
assist in the determination of whether an emerging contaminant is a problem of national  extent and
should be considered for health-based standards or advisories. EPA will issue guidance explaining


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how data on the occurrence of contaminants not on the UCMR (1999) List may be voluntarily
reported to the NCOD.

Large PWSs may also wish to report previously collected data on the occurrence of UCMR (1999)
List 1 contaminants in lieu of participating in Assessment Monitoring. To ensure the quality of data
included in the NCOD, EPA is requiring that any data previously collected and submitted in lieu of
UCMR monitoring must meet all analytical method and quality control requirements specified in
the UCMR and in this Manual.
Table 7.1 UCMR Reporting Requirements Sample Data Elements
Data Element
1. Public Water System
(PWS) Identification
Number
2. Public Water System
Facility Identification
Number - Source,
Treatment Plant, and
Sampling Point
3. Sample Collection Date
4. Sample Identification
Number
5. Contaminant/Parameter
6. Analytical Results - Sign
7. Analytical Result - Value
8. Analytical Result - Unit of
Measure
9. Analytical Method
Number
Definition
The code used to identify each PWS. The code begins with the standard two-
character postal State abbreviation; the remaining seven characters are unique to
each PWS. .
An identification number established by the State, or, at the State's discretion
the PWS, that is unique to the system for an intake for each source of water, a
treatment plant, and a sampling point. Within each PWS, each intake, treatment
plant, and sampling point must receive a unique identification number,
including, for intake; surface water intake, ground water well, or wellfield
centroid; and including, for sampling point; entry points to the distribution
system, wellhead, intake, locations within the distribution system, or other
representative sampling point specified by the State. The same identification
number must be used consistently through the history of unregulated
contaminant monitoring to represent the facility.
The date the sample is collected reported as 4-digit year, 2-digit month and 2-
digit day.
A unique identifier assigned by the PWS for each sample.
The unregulated contaminant or water quality parameter for which the sample is
being analyzed.
An alphanumeric value indicating whether the sample analysis result was:
(a) (<) "less than" means the contaminant was not detected or was detected at a
level "less than" the MRL.
(b) (=) "equal to" means the contaminant was detected at a level "equal to" the
value reported in "Analytical Result - Value."
The actual numeric value of the analysis for chemical and microbiological
results, or the Minimum Reporting Level (MRL) if the analytical result is less
than the specified contaminant's MRL.
The unit of measurement for the analytical results reported, [e.g., micrograms
per liter, (/wg/L); colony-forming units per milliliter, (CFU/mL), etc.]
The identification number of the analytical method used.
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IData Element
10. Sample Analysis Type
11. Sample Batch
Identification Number
12. Detection Level
13. Detection Level Unit of
Measure
14. Analytical Precision
j
15. Analytical Accuracy
16. Spiking Concentration
17. Presence/Absence
	 ~ ~~~~^r==r=^=
Definition |
The type of sample collected. Permitted values include:
(a) Field Sample - sample collected and submitted for analysis under this
Rule.
(b) Batch Spike/Spike Duplicate - Samples associated with a batch used for
calculating analytical precision and accuracy. A batch is defined as the set
of field samples plus one spiked sample and one spiked duplicate sample
to analyzed for contaminant concentrations.
A number assigned by the laboratory to the batch of samples analyzed with the
spiked sample (at the spiking concentration reported), to be reported as 9-digit
laboratory number (assigned by the State or EPA), 4-digit year, 2-digit month
2-digit day, and 2-digit batch number.
"Detection level" is referring to the detection limit applied to both the method
and equipment. Detection limits are the lowest concentration of a target
contaminant that a given method or piece of equipment can reliably ascertain
and report as greater than zero ( e.g., Instrument Detection Limit, Method
Detection Limit, or Estimated Detection Limit).
The unit of measure to express the concentration, count, or other value of a
contaminant level for the detection level reported, [e.g., micrograms per liter,
Og/L); colony-forming units per milliliter, (CFU/mL), etc.]
Precision is the degree of agreement among a set of repeated measurements and
is monitored through the use of replicate samples or measurements. For the
Durposes of the UCMR, Analytical Precision is defined as the relative percent
difference (RPD) between spiked matrix duplicates. The RPD for the spiked
matrix duplicates analyzed in the same batch of samples as the analytical result
jeing reported is to be entered in this field. Precision is calculated as the RPD
between spiked matrix duplicates using;
RPD = [(X, - Xj) / {(X, + XJ/2}] x 100
Accuracy describes how close a result is to the true value measured through the
use of spikes, standards, surrogates or performance evaluation samples. For the
>urposes of the UCMR, Analytical Accuracy is defined as the percent recovery
>f me contaminant in the spiked matrix sample analyzed in the same analytical
jatch as the sample result being reported and calculated using;
% recovery = [(amount found in Spiked sample - amount found in sample) /
amount spiked] x 100
"he concentration of method analytes added to a sample to be analyzed for
calculating analytical precision and accuracy where the value reported uses the
ame unit of measure reported for Analytical Results.
Qhemicals: Presence- a response was produced by the analysis (i e greater than
or equal to the MDL but less than the MRL)/Absence- no response 'was ~"
jroduced by the analysis (i.e., less than the MDL).
Microbiolpgicals: Presence- indicates a response was produced by the analysis
Absence- indicates no response was produced by the analysis
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                                    Appendix A

                            Abbreviations and Acronyms
 2,4-DNT
 2,6-DNT
 4,4'-DDE

 Alachlor ESA
 AOAC
 APHA
 ASDWA
 ASTM

 BGM

 CAS
 CASRN
 CCL
 CCR
 CERCLA
 CFR
 CPU
 CFU/mL
 CWS

 DCPA
 DCPA mono-
 and di-acid
 degradates
 DDE
 DDT
 DNA

 EDL
 EPA
 EPTC
 EPTDS
 ESA

 FACA
 FTE

 GC
 GLI method
 GW
 GUDI
  - 2,4-dinitrotoluene
  • 2,6-dinitrotoluene.
  • 4,4-dichloro dichlorophenyl ethylene, a degradation product of DDT

  • alachior ethanesulfonic acid, a degradation product of alachlor
 - Association of Official Analytical Chemists
 - American Public Health Association
 - Association of State Drinking Water Administrators
 - American Society for Testing and Materials

 - Buffalo Green Monkey cells, a specific cell line used to grow viruses

 - Chemical Abstract Service
 - Chemical Abstract Service Registry Number
 - Contaminant Candidate List
 - Consumer Confidence Reports
 - Comprehensive Environmental Response, Compensation & Liability Act
 - Code of Federal Regulations
 - colony fprming unit
 - colony forming units per milliliter
 - community water system

 - dimethyl tetrachloroterephthalate, chemical name of the herbicide dacthal


 - degradation products of DCPA
 - dichloro dichlorophenyl ethylene, a degradation product of DDT
 - dichloro diphenyl trichloroethane, a general insecticide
 - deoxyribonucleic acid

 - estimated detection limit
 - Environmental Protection Agency
 - s-ethyl-dipropylthiocarbamate, an herbicide
 - Entry Point to the Distribution System
 - ethanesulfonic acid, a degradation product of alachlor

 - Federal Advisory Committee Act
 - full-time equivalent

 - gas chromatography, a laboratory method
 - Great Lakes Instruments method
- ground water
- ground water under the direct influence (of surface water)
HPLC       - high performance liquid chromatography, a laboratory method
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 UCMR Analytical Methods and Quality Control Manual
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 ICR
 IRFA
 IMS
 IRIS
 IS

 LLE

 MAC
 MOA
 MCL
 MDL
 MRL
 MS
 MS
 MSD
 MTBE

 NAWQA
 NCOD
 NDWAC
 NERL
 NFS
 NTIS
 NTNCWS
 NTTAA

 OGWDW
 OMB

 PAH
 PB
 PBMS
 pCi/L
 PCR
 210pb   •

 2IOPo
PWS
PWSF

QA
QC

RDX
RFA
RPD
RSD
 - Information Collection Request / Rule
 - initial regulatory flexibility analysis
 - immunomagnetic separation
 - Integrated Risk Information System
 - internal standard

 - liquid/liquid extraction, a laboratory method

 - Mycobacterium avium complex
 - Memorandum of Agreement
 - maximum contaminant level
 - method detection limit
 - minimum reporting level
 - mass spectrornetry, a laboratory method
 - sample matrix spike
 - sample matrix spike duplicate
 - methyl tertiary-butyl ether, a gasoline additive

 - National Water Quality Assessment Program
 - National Drinking Water Contaminant Occurrence Database
 - National Drinking Water Advisory Council
 - National Environmental Research Laboratory
 - National Pesticide Survey
 - National Technical Information Service
 - non-transient non-community water system
 - National Technology Transfer and Advancement Act

 - Office of Ground Water and Drinking Water
 - Office of Management and Budget

 - Poly-aromatic hydrocarbon
 - particle beam
 - Performance-Based Measurement System
 - picocuries per liter
 - polymerase chain reaction
 - Lead-210 (also Pb-210), a lead isotope and radionuclide; part of the uranium decay
 series
 - Polonium-210 (also Po-210), a polonium isotope and radionuclide; part of the
 uranium decay series

 - Public Water System
 - Public Water System Facility

 - quality assurance
 - quality control

- royal demolition explosive, hexahydro-l,3,5-trinitro-l,3,5-triazine
- Regulatory Flexibility Act
- relative percent difference
- relative standard deviation
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 SBREFA
 SD
 SDWA
 S.DWIS
 SDWIS FED
 SM
 SMF
 soc
 SPE
 SRF
 STORE!
 SW

 TBD
 TNCWS

 UCMR
 UCM
 UMRA
 USEPA
uv

voc
- Small Business Regulatory Enforcement Fairness Act
- standard deviation
- Safe Drinking Water Act
- Safe Drinking Water Information System
- the Federal Safe Drinking Water Information System
- Standard Methods
- Standard Compliance Monitoring Framework
- synthetic organic compound
- solid phase extraction, a laboratory method
- State Revolving Fund
- Storage and Retrieval System
- surface water

- to be determined
- transient non-community water system

- Unregulated Contaminant Monitoring Regulation/Rule
- Unregulated Contaminant Monitoring
- Unfunded Mandates Reform Act of 1995
- United States Environmental Protection Agency
- ultraviolet

- volatile organic compound

- micrograms per liter
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                                     Appendix  B

                                      Definitions


 All monitored systems means all community water systems serving more than 10,000 people, and
 the national representative sample of community and non-transient non-community water systems
 serving 10,000 or fewer people that are selected to be part of a State Plan for the UCMR.

 Assessment Monitoring means sampling, testing, and reporting of listed contaminants that have
 available analytical methods and for which preliminary data indicate their possible occurrence in
 drinking  water.  All monitored systems  must  conduct Assessment Monitoring.   Assessment
 Monitoring will be conducted for the UCMR (1999) List 1 contaminants.

 Index systems means a limited number of small CWSs and NTNCWSs, randomly selected from the
 systems in State Plans, that must monitor for UCMR contaminants and also additionally must report
 information on system operating conditions (such as water source, pumping rates, and environmental
 setting). These systems must monitor and report quarterly each year of the 5-year UCMR cycle with
 EPA paying for all reasonable monitoring costs.  This'more detailed and regular monitoring  of
 contaminants  and operating conditions will provide important information with which EPA can
 more fully evaluate conditions under which systems operate and will enable comparisons between
 system operations of similar size and characteristics.

 Listed contaminant means a contaminant identified as an analyte in Table 1, 141.40(a)(3) of the
 Unregulated Contaminant Monitoring Regulation (UCMR). To distinguish the current 1999 UCMR
 listed contaminants from potential future UCMR  listed contaminants, all references to UCMR
 contaminant lists will identify the appropriate year in parenthesis immediately following the acronym
 UCMR and before the referenced list. For example, the contaminants included in the UCMR (1999)
 List include the component lists identified as UCMR (1999) List 1, UCMR (1999) List 2 and UCMR
 (1999) List 3 contaminants.

 Listing cycle means the 5-year period for which  each revised UCMR list is effective and during
 which no  more than 30 unregulated contaminants from file list may be required to be monitored
 EPA is mandated to develop and promulgate a new UCMR List every 5 years.

 Monitoring means (as distinct from Assessment Monitoring), all aspects of determining the quality
 of drinking water relative to the listed contaminants.  These aspects include drinking water sampling
 and testing, and the reviewing, reporting, and submission to  EPA of analytical results.

 Most vulnerable systems  for Systems most vulnerable) means a subset of 5 to not more than 25
 systems of all monitored systems in a State that are determined by that State in consultation with the
 EPA Regional Office to be most likely to have the listed contaminants occur in their drinking waters
 considering the characteristics of the listed contaminants, precipitation, system operation,  and
 environmental conditions (soils, geology and land use).

Pre-Screen Testing means sampling, testing, and reporting of the listed contaminants that may have
newly emerged as drinking water concerns and, in most cases, for which methods are in an early
StSf ™f development.  Pre-Screen Testing must be conducted by a limited number of systems  (up
to 200). The Pre-Screen Testing systems will be selected through the use of a random number
generator,  and from a list comprised of the States' nominations of up to 25 of the most vulnerable
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  systems per State. Pre-Screen Testing will be performed to determine whether a listed contaminant
  occurs in sufficient frequency in the most vulnerable systems or sampling locations to warrant its
  being included in future Assessment Monitoring or Screening Surveys. Pre-Screen Testing will be
  conducted for the UCMR (1999) List 3 contaminants.
                 "i

  Random Sampling is a statistical sampling method by which each member of the population has an
  equal probability (an equal random chance) of being selected as part of a sample (the sample being
  a small subset of the population which represents the population as a whole).

  Representative Sample means a subset of community and non-transient non-community water
  systems serving  10,000 or fewer people which EPA selects using  a random number generator to
  obtain public water system identification numbers to place them on the first representative sample
  list. The selection is weighted by population served within a State, water source and then by size
  categories of 10,000 to 3,301 people, 3,300 to 501 people, and 500 or fewer people; a State may
  substitute systems from a replacement list of such systems derived through the same method for
  systems hi the first list because a system on the first list is closed, merged or purchases water from
  another system.

 Sampling means  the act of collecting water from the appropriate location in a public water system
 (from the applicable point from an intake or well to the end of a distribution line, or in some limited
 cases, a residential tap)  following proper methods for the particular contaminant or group of
 contaminants.

 Sampling Point means a unique location where UCMR samples are to be collected.

 Screening Survey means sampling, testing, and reporting of the listed contaminants for which
 analytical methods are recently developed and have uncertain potential for occurrence in drinking
 water by a subset of approximately 300 systems from all monitored systems selected through use of
 a random number generator for public water system identification numbers. These systems must
 conduct the Screening Survey for the listed  contaminants after public notice and  comment to
 determine whether a listed contaminant occurs at a sufficient frequency and  concentration (or
 density) to warrant being included in future Assessment Monitoring. Two Screening Survevs will
 be conducted for the UCMR (1999) List 2 contaminants.

 State means, for the purposes of this section, each of the fifty States, the District of Columbia, U S
 Territories, and Tribal lands. For the national representative sample, Guam, the Commonwealth of
 Puerto Rico, the Northern Mariana Islands, the Virgin Islands, American Samoa, and the Trust
 lemtones of the Pacific Islands are treated as a State. Any Indian Tribe which has status as a State
 under Section 1451 of the Safe Drinking Water Act for this program will be considered as a State.

 State Monitoring Plan (or State Plan) means a State's portion of the national representative sample
 of CWSs and NTNCWSs serving 10,000 or fewer people which must monitor for  unregulated
 contaminants.  A State Plan may be developed by a State's acceptance of EPA's  representative
 sample for that State, or by a State's selection of systems from a replacement list (provided by EPA)
 to replace original systems listed that are determined to be closed or merged, or that purchase water
 from another system.  The State Plan may be part of the State-EPA Memorandum of Agreement that
 will also include a process by which the State will inform each public water system of its selection
 tor the plan and of its responsibilities to monitor. A State Plan will also include the systems required
to conduct Pre-Screen Testing, selected from the State's designation of vulnerable systems
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 Stratified Random Sampling is a procedure to draw a random sample from a population that has been
 divided into subpopulations or strata, with each stratum comprised of a population subset sharing
 common characteristics.  Random samples are  selected from each stratum proportional to that
 stratum's proportion of the entire population. The aggregate random sample (compiled from all the
 strata samples) provides a random sample of the entire population that reflects the proportional
 distribution of characteristics of the population. In the context of the UCMR, the population of
 public water systems was stratified by size category (based on population served by the water
 system) and by the system's water source type (ground water or surface water).  This stratification
 was done to  ensure that systems randomly selected as nationally representative sample systems
 would proportionally reflect the actual number of size and water type categories nationally.

 Testing means, for the UCMR and distinct from Pre-Screen Testing, the submission and/or shipment
 of samples following appropriate preservation practices to protect the integrity of the sample; the
 chemical, radiological, physical and/or microbiological amalysis of samples; and the reporting of the
 sample's analytical results for evaluation. Testing is a subset of activities defined as monitoring.

 Unregulated contaminants means chemical, microbiological, radiological and other substances that
 occur in drinking water or sources of drinking water that are not currently regulated under the federal
 drinking water program.  EPA has not issued standards for these substances in drinking water (i.e.,
 maximum contaminant levels or treatment technology requirements). EPA is required by Congress
 to establish a program to monitor for selected unregulated contaminants in public water systems to
 determine whether they should be considered for future regulation to protect public health.  The
 selected contaminants are listed hi 141.40(a)(3), Table 1, the UCMR List.

 Vulnerable time (or vulnerable period) means the time (or, hi some cases, the 3-month quarter) of
 the year determined as the most likely to have the listed group of contaminants present at their
 highest concentrations or densities in drinking water.  The vulnerable determination, in the case of
 the UCMR, is made by the EPA  or by the  State (under arrangement with the EPA) for a system,
 subset of systems, or all systems in a State. The vulnerable determination is based on characteristics
 of the contaminants, precipitation, system operations, and environmental conditions such as soil
types, geology, and land use.  This determination  does not indicate or  imply that the listed
contaminants will be identified  in the drinking water with certainty, but only that  sampling
conducted during the vulnerable period presumably has the highest likelihood of identifying those
contaminants in higher concentrations relative to other sampling times of the year, if and when the
contaminants occur.
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                                    Appendix C

            Procedure for Determination of Method Detection Limits

 Definition

 The method detection limit (MDL) is defined as the minimum concentration of a substance that can
 be measured and reported with 99% confidence that the analyte concentration is greater than zero
 and is determined from analysis of a sample in a given matrix containing the analyte.


 Scope and Application

 This procedure is designed for applicability to a wide variety of sample types ranging from reagent
 (blank)  water  containing analyte to wastewater containing analyte. The MDL for an analytical
 procedure may vary as a function of sample type. The procedure requires a complete, specific, and
 well defined analytical method.  It is essential that all sample processing steps of the analytical
 method be included in the determination of the method detection limit.

 The MDL obtained by this procedure is used to judge the significance of a single measurement of
 a future sample. The MDL procedure was designed for applicability to a broad variety of physical
 and  chemical methods.  To  accomplish   this,  the  procedure  was   made  device-   or
 instrument-independent.


 Procedure

 1.  Make an estimate of the detection limit using one of the following:

  1. The concentration value that corresponds to an instrument signal/noise in the range of 2.5  to


  2. The concentration equivalent of three times the standard deviation of replicate instrumental
     measurements of the analyte in reagent water.

  3.  That region of the standard curve where there is a significant change in sensitivity, i.e., a break
     in the slope of the standard curve.

 4.  Instrumental limitations.  It is recognized that the experience of the analyst is important to this
     process. However, the analyst must include the above considerations in the initial estimate  of
     the detection limit.

2.  Prepare reagent (blank) water that is as free of analyte as possible. Reagent or interference free
   water is defined as a  water sample in which analyte and  interfering concentrations are not
   detected at  the method detection limit of each analyte of interest. Interferences  are defined as
   systematic errors in the measured analytical signal of an established procedure caused by the
   presence of interfering species (interfering). The interfering concentration is presupposed to be
   normally distributed in representative samples of a given matrix.
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 —                                             .          .       .

  (a)  If the MDL is to be determined in reagent (blank) water, prepare a laboratory standard (analyte
      in reagent water) at a concentration which is at least equal to or in the same concentration
      range as the estimated method detection limit. (Recommend between 1 and 5 times the
      estimated method detection limit.) Proceed to Step 4.

  (b)  If the MDL is to be determined in another sample matrix, analyze the sample. If the measured
      level of the analyte is in the recommended range of one to five times the estimated detection
      limit, proceed to Step 4. If the measured level of analyte is less than the estimated detection
      limit, add a known amount of analyte to bring the level of analyte between one and five times
      the estimated detection limit. If the measured level of analyte is greater than five times the
      estimated detection limit, there are two options.

      (1) Obtain another sample with a lower level of analyte in the same matrix if possible.

      (2) The sample may be used as is for determining the method detection limit if the analyte
         level  does not exceed 10 times the MDL of the analyte in reagent water. The variance of
         the analytical method changes as the analyte concentration increases from the MDL, hence
         the MDL determined under these circumstances may not truly reflect method variance at
         lower analyte concentrations.

4.
  (a) Take a minimum of seven aliquots of the sample to be used to calculate the method detection
      limit and process each through the entire analytical method. Make all computations according
     to the defined method with final results in the method reporting units. If a blank measurement
      is required to calculate the measured level of analyte, obtain a separate blank measurement for
      each sample aliquot analyzed.  The average  blank measurement is subtracted from the
     respective sample measurements.

  (b) It may be economically and technically desirable to evaluate the estimated method detection
     limit before proceeding with 4a. This will:

     (1) prevent repeating this entire procedure when the costs of analyses are high, and

     (2) ensure that the procedure is being conducted at the correct concentration.  It is quite
        possible that an inflated MDL will be calculated from data obtained, at many times the real
        MDL even though the level of  analyte is less than five  times the calculated method
        detection limit. To insure that the estimate of the method detection limit is a good estimate,
        it is necessary to determine that a lower concentration of analyte will  not result in a
        significantly lower method detection limit. Take two aliquots of the sample to be used to
        calculate the method detection limit and process each through the entire method, including
        blank measurements as described above in 4a. Evaluate these data:

        (1)  If these measurements indicate the sample is in desirable range for determination of
           the MDL, take five additional aliquots and proceed. Use all seven measurements for
           calculation of the MDL.

        (2) If these measurements indicate the sample is not in correct range, reestimate the MDL,
           obtain new sample as in 3 and repeat either 4a or 4b.
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 5.  Calculate  the variance  (S2) and  standard  deviation (S) of the replicate
    measurements, as follows:
                                n-l i=\s       n
       where:
       Xs; i = 1 to n, are the analytical results in the final method reporting units obtained from the
       n sample aliquots and £ refers to the sum of the X values from i=Uo n.

6.
  (a) Compute the MDL as follows:
             = t(n.1;1.oe=0.99)(S)

       where:

       MDL = the method detection limit t(n.1( ^^g.99) == me students' t value appropriate for a 99%
       confidence level and a standard deviation estimate with n-1 degrees of freedom. (See Table.)
       S = standard deviation of the replicate analyses.
  (b) The 95% confidence interval estimates for the MDL derived in 6a are computed according to
     the following equaf — - J--=—"-       -   <-     -•<   <•             *        --   -
     distribution (x2/df).
the following equations derived from percentiles of the chi square over degrees of freedom
       LCL = 0.64 MDL
       UCL = 2.20 MDL                                           *

       where:

       LCL and UCL are the lower and upper 95% confidence limits, respectively, based on seven
       aliquots.

7.  Optional iterative procedure to verify the reasonableness of the estimate of the MDL and
   subsequent MDL determinations.

 (a) If this is the initial attempt to compute MDL based on the estimate of MDL formulated hi Step
     1, take the MDL as calculated in Step 6, spike the matrix at this calculated MDL and proceed
     through the procedure starting with Step 4.

 (b) If this is the second or later iteration of the MDL calculation, use S2 from the current MDL
     calculation and S2 from the previous MDL calculation to compute the F-ratio. The F-ratio is
     calculated by substituting the  larger S2 into the  numerator S2A and the other into the
     denominator S B. The computed F-ratio is then compared with the F-ratio found in the table
     which is 3.05 as follows:
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                                                                             August 1999
     if S A/S B<3.05, then compute the pooled standard deviation by the following equation:
                                   pooled
                                      -r
                                      -[
                                             12
                                                   ,
                                                  -\\
                                                  J
     if S A/S B<3.05, re-spike at the most recent calculated MDL and process the samples through
     the procedure starting with Step 4. If the most recent calculated MDL does not  permit
     qualitative identification when samples are spiked at that level, report the MDL as a
     concentration between the current and previous MDL which permits qualitative identification.
(c) Use the
   equation:
                  as calculated in 7b to compute The final MDL according to the following
      MDL=2.681 (S^

      where 2.681 is equal to t(12, i.«*=o 99) •

 (d) The 95% confidence limits for MDL derived in 7c are computed according to the following
    equations derived from percentiles of the chi squared over degrees of freedom distribution.

      LCL=0.72 MDL
      UCL=1.65 MDL

      where LCL and UCL are the lower and upper 95% confidence limits, respectively, based on
      14 aliquots.
Table of Students' t Values at the 99 Percent Confidence Level
Number of replicates
7
8
9
10
11
16
21
26
31
61
00
Degrees of Freedom (n-1)
6
7
8
9
10
15
20
25
30
60
00
Wl_»
3.143
2.998
2.896
2.821
2.764
2.602
2.528
2.485
2.457
2.390

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 Reporting

 The analytical method used must be specifically identified by number or title and the MDL for each
 analyte expressed hi the appropriate method reporting units. If the analytical method permits options
 which affect the method detection limit, these conditions must be specified with the MDL value. The
 sample matrix used to determine the MDL must also be identified with MDL value. Report the mean
 analyte level with the MDL and indicate if the MDL procedure was iterated. If a laboratory standard
 or a sample that contained a known amount analyte was used for this determination, also report the
 mean recovery.


 (This procedure is from Title 40-Protection of Environment, Chapter I-Environmental Protection
Agency, Part 13 6-Guidelines Establishing Test Procedures for the Analysis of Pollutants. Appendix
B to  Part 136—Definition and Procedure for the  Determination of the  Method Detection
Limit-Revision 1.11.)   [49 FR 43430, Oct. 26, 1984; 50 FR 694, 696, Jan. 4, 1985, as amended
at 51 FR 23703, June 30, 1986]
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