extract that has been diluted at the least dilute level at which the
area at the quantitation m/z is within the calibration range (i.e.,
above the ML for the analyte) and the MS/MSD recovery and RPD are
within their respective QC acceptance criteria (Table 6). This may
require reporting results for some analytes from different analyses.
    15.2.3 Results from tests performed with an analytical system that
is not in control (i.e., that does not meet acceptance criteria for all
of QC tests in this method) must not be reported or otherwise used for
permitting or regulatory compliance purposes, but do not relieve a
discharger or permittee of reporting timely results. If the holding
time would be exceeded for a re-analysis of the sample, the regulatory/
control authority should be consulted for disposition.
16. Method Performance
    16.1 The basic version of this method was tested by 15 laboratories
using reagent water, drinking water, surface water, and industrial
wastewaters spiked at six concentrations over the range 5-1300 [mu]g/L
(Reference 2). Single operator precision, overall precision, and method
accuracy were found to be directly related to the concentration of the
analyte and essentially independent of the sample matrix. Linear
equations to describe these relationships are presented in Table 7.
    16.2 As noted in Sec. 1.1, this method was validated through an
interlaboratory study conducted more than 29 years ago. However, the
fundamental chemistry principles used in this method remain sound and
continue to apply.
    16.3 A chromatogram of the combined acid/base/neutral calibration
standard is shown in Figure 2.
17. Pollution Prevention
    17.1 Pollution prevention encompasses any technique that reduces or
eliminates the quantity or toxicity of waste at the point of
generation. Many opportunities for pollution prevention exist in
laboratory operations. EPA has established a preferred hierarchy of
environmental management techniques that places pollution prevention as
the management option of first choice. Whenever feasible, the
laboratory should use pollution prevention techniques to address waste
generation. When wastes cannot be reduced at the source, the Agency
recommends recycling as the next best option.
    17.2 The analytes in this method are used in extremely small
amounts and pose little threat to the environment when managed
properly. Standards should be prepared in volumes consistent with
laboratory use to minimize the disposal of excess volumes of expired
standards. This method utilizes significant quantities of methylene
chloride. Laboratories are encouraged to recover and recycle this and
other solvents during extract concentration.
    17.3 For information about pollution prevention that may be applied
to laboratories and research institutions, consult Less is Better:
Laboratory Chemical Management for Waste Reduction, available from the
American Chemical Society's Department of Governmental Relations and
Science Policy, 1155 16th Street NW., Washington, DC 20036, 202/872-
4477.
18. Waste Management
    18.1 The laboratory is responsible for complying with all Federal,
State, and local regulations governing waste management, particularly
the hazardous waste identification rules and land disposal
restrictions, and to protect the air, water, and land by minimizing and
controlling all releases from fume hoods and bench operations.
Compliance is also required with any sewage discharge permits and
regulations. An overview of requirements can be found in Environmental
Management Guide for Small Laboratories (EPA 233-B-98-001).
    18.2 Samples at pH <2, or pH >12 are hazardous and must be
neutralized before being poured down a drain, or must be handled and
disposed of as hazardous waste.
    18.3 Many analytes in this method decompose above 500 [deg]C. Low-
level waste such as absorbent paper, tissues, and plastic gloves may be
burned in an appropriate incinerator. Gross quantities of neat or
highly concentrated solutions of toxic or hazardous chemicals should be
packaged securely and disposed of through commercial or governmental
channels that are capable of handling these types of wastes.
    18.4 For further information on waste management, consult The Waste
Management Manual for Laboratory Personnel and Less is Better-
Laboratory Chemical Management for Waste Reduction, available from the
American Chemical Society's Department of Government Relations and
Science Policy, 1155 16th Street NW., Washington, DC 20036, 202/872-
4477.

19. References
1. ``Sampling and Analysis Procedures for Screening of Industrial
Effluents for Priority Pollutants,'' U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory, Cincinnati,
Ohio 45268, March 1977, Revised April 1977.
2. ``EPA Method Study 30, Method 625, Base/Neutrals, Acids, and
Pesticides,'' EPA 600/4-84-053, National Technical Information Service,
PB84-206572, Springfield, Virginia 22161, June 1984.
3. 40 CFR part 136, appendix B.
4. Olynyk, P., Budde, W.L. and Eichelberger, J.W. ``Method Detection
Limit for Methods 624 and 625,'' Unpublished report, May 14, 1980.
5. Annual Book of ASTM Standards, Volume 11.02, D3694-96, ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
6. Solutions to Analytical Chemistry Problems with Clean Water Act
Methods, EPA 821-R-07-002, March 2007.
7. ``Carcinogens-Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
8. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR part
1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
9. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 7th Edition, 2003.
10. http://en.wikipedia.org/wiki/Coefficient_of_determination (accessed
on 09/10/2013).
11. 40 CFR 136.6(b)(4)(x).
12. 40 CFR 136.6(b)(2)(i).
13. Protocol for EPA Approval of New Methods for Organic and Inorganic
Analytes in Wastewater and Drinking Water (EPA-821-B-98-003) March
1999.
14. Provost, L.P. and Elder, R.S. ``Interpretation of Percent Recovery
Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44 used in
the equation in Section 8.3.3 is two times the value 1.22 derived in
this report.)
15. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
16. 40 CFR 136.3(a), Table IB, Chlorine--Total Residual.
17. ``Manual of Analytical Methods for the Analysis of Pesticides in
Human and Environmental Samples,'' EPA-600/8-80-038, U.S. Environmental
Protection Agency, Health Effects Research Laboratory, Research
Triangle Park, North Carolina.
18. Eichelberger, J.W., Harris, L.E., and Budde, W.L. ``Reference
Compound to Calibrate Ion Abundance Measurement in Gas Chromatography-
Mass Spectrometry,'' Analytical Chemistry, 47, 995 (1975).
19. Letter of approval of acceptance criteria for DFTPP for time-of-
flight mass spectrometers from William A. Telliard and Herb Brass of
EPA to Jack Cochran of LECO Corporation, February 9, 2005.
20. Tables.

                            Table 1--Non Pesticide/PCB Base/Neutral Extractables \1\
----------------------------------------------------------------------------------------------------------------
                             Analyte                               CAS Registry       MDL \4\         ML \5\
----------------------------------------------------------------------------------------------------------------
Acenaphthene....................................................         83-32-9             1.9             5.7
Acenaphthylene..................................................        208-96-8             3.5            10.5
Anthracene......................................................        120-12-7             1.9             5.7
Benzidine \2\...................................................         92-87-5              44             132
Benzo(a)anthracene..............................................         56-55-3             7.8            23.4
Benzo(a)pyrene..................................................         50-32-8             2.5             7.5
Benzo(b)fluoranthene............................................        205-99-2             4.8            14.4
Benzo(k)fluoranthene............................................        207-08-9             2.5             7.5
Benzo(ghi)perylene..............................................        191-24-2             4.1            12.3
Benzyl butyl phthalate..........................................         85-68-7             2.5             7.5
bis(2-Chloroethoxy)methane......................................        111-91-1             5.3            15.9
bis(2-Ethylhexyl)phthalate......................................        117-81-7             2.5             7.5
bis(2-Chloroisopropyl) ether (2,2'-Oxybis(1-chloropropane)).....        108-60-1             5.7            17.1
4-Bromophenyl phenyl ether......................................        101-55-3             1.9             5.7
2-Chloronaphthalene.............................................         91-58-7             1.9             5.7
4-Chlorophenyl phenyl ether.....................................       7005-72-3             4.2            12.6
Chrysene........................................................        218-01-9             2.5             7.5
Dibenz(a,h)anthracene...........................................         53-70-3             2.5             7.5
Di-n-butylphthalate.............................................         84-74-2             2.5             7.5
3,3'-Dichlorobenzidine..........................................         91-94-1            16.5            49.5
Diethyl phthalate...............................................         84-66-2             1.9             5.7
Dimethyl phthalate..............................................        131-11-3             1.6             4.8
2,4-Dinitrotoluene..............................................        121-14-2             5.7            17.1
2,6-Dinitrotoluene..............................................        606-20-2             1.9             5.7
Di-n-octylphthalate.............................................        117-84-0             2.5             7.5
Fluoranthene....................................................        206-44-0             2.2             6.6
Fluorene........................................................         86-73-7             1.9             5.7
Hexachlorobenzene...............................................        118-74-1             1.9             5.7
Hexachlorobutadiene.............................................         87-68-3             0.9             2.7
Hexachloroethane................................................         67-72-1             1.6             4.8
Indeno(1,2,3-cd)pyrene..........................................        193-39-5             3.7            11.1
Isophorone......................................................         78-59-1             2.2             6.6
Naphthalene.....................................................         91-20-3             1.6             4.8
Nitrobenzene....................................................         98-95-3             1.9             5.7
N-Nitrosodi-n-propylamine \3\...................................        621-64-7              --              --
Phenanthrene....................................................         85-01-8             5.4            16.2
Pyrene..........................................................        129-00-0             1.9             5.7
1,2,4-Trichlorobenzene..........................................        120-82-1             1.9             5.7
----------------------------------------------------------------------------------------------------------------
\1\ All analytes in this table are Priority Pollutants (40 CFR part 423, appendix A).

\2\ Included for tailing factor testing.
\3\ See Section 1.2.
\4\ MDL values from the 1984 promulgated version of Method 624.
\5\ ML = Minimum Level--see Glossary for definition and derivation.

                                         Table 2--Acid Extractables \1\
----------------------------------------------------------------------------------------------------------------
                             Analyte                               CAS Registry       MDL \3\         ML \4\
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol.........................................         59-50-7             3.0             9.0
2-Chlorophenol..................................................         95-57-8             3.3             9.9
2,4-Dichlorophenol..............................................        120-83-2             2.7             8.1
2,4-Dimethylphenol..............................................        105-67-9             2.7             8.1
2,4-Dinitrophenol...............................................         51-28-5              42             126
2-Methyl-4,6-dinitrophenol......................................        534-52-1              24              72
2-Nitrophenol...................................................         88-75-5             3.6            10.8
4-Nitrophenol...................................................        100-02-7             2.4             7.2
Pentachlorophenol \2\...........................................         87-86-5             3.6            10.8
Phenol..........................................................        108-95-2             1.5             4.5
2,4,6-Trichlorophenol...........................................         88-06-2             2.7             8.1
----------------------------------------------------------------------------------------------------------------
\1\ All analytes in this table are Priority Pollutants (40 CFR part 423, appendix A).
\2\ See Section 1.2; included for tailing factor testing.
\3\ MDL values from the 1984 promulgated version of Method 624.
\4\ ML = Minimum Level--see Glossary for definition and derivation.

                                Table 3--Additional Extractable Analytes \1\ \2\
----------------------------------------------------------------------------------------------------------------
                             Analyte                               CAS Registry       MDL \6\         ML \7\
----------------------------------------------------------------------------------------------------------------
Acetophenone....................................................         98-86-2
2-Acetylaminofluorene...........................................         53-96-3
1-Acetyl-2-thiourea.............................................        591-08-2
Alachlor........................................................      15972-60-8
Aldrin \3\......................................................        309-00-2             1.9             5.7
Ametryn.........................................................        834-12-8
2-Aminoanthraquinone............................................        117-79-3
Aminoazobenzene.................................................         60-09-3
4-Aminobiphenyl.................................................         92-67-1
3-Amino-9-ethylcarbazole........................................        132-32-1
Anilazine.......................................................        101-05-3
Aniline.........................................................         62-53-3
o-Anisidine.....................................................         90-04-0
Aramite.........................................................        140-57-8
Atraton.........................................................       1610-17-9
Atrazine........................................................       1912-24-9
Azinphos-methyl.................................................         86-50-0
Barban..........................................................        101-27-9
Benzanthrone....................................................         82-05-3
Benzenethiol....................................................        108-98-5
Benzidine \3\ \4\...............................................         92-87-5              44             132
Benzoic acid....................................................         65-85-0
2,3-Benzofluorene...............................................        243-17-4
p-Benzoquinone..................................................        106-51-4
Benzyl alcohol..................................................        100-51-6
alpha-BHC \3\ \4\...............................................        319-84-6
beta-BHC \3\....................................................        319-85-7             3.1             9.3
gamma-BHC (Lindane) 3 4.........................................         58-89-8             4.2            12.6
delta-BHC \3\...................................................        319-86-8
Biphenyl........................................................         92-52-4
Bromacil........................................................        314-40-9
2-Bromochlorobenzene............................................        694-80-4
3-Bromochlorobenzene............................................        108-39-2
Bromoxynil......................................................       1689-84-5
Butachlor.......................................................       2318-4669
Butylate........................................................       2008-41-5
n-C10 (n-decane)................................................        124-18-5
n-C12 (n-undecane)..............................................        112-40-2
n-C14 (n-tetradecane)...........................................        629-59-4
n-C16 (n-hexadecane)............................................        544-76-3
n-C18 (n-octadecane)............................................        593-45-3
n-C20 (n-eicosane)..............................................        112-95-8
n-C22 (n-docosane)..............................................        629-97-0
n-C24 (n-tetracosane)...........................................        646-31-1
n-C26 (n-hexacosane)............................................        630-01-3
n-C28 (n-octacosane)............................................        630-02-4
n-C30 (n-triacontane)...........................................        638-68-6

Captafol........................................................       2425-06-1
Captan..........................................................        133-06-2
Carbaryl........................................................         63-25-2
Carbazole.......................................................         86-74-8
Carbofuran......................................................       1563-66-2
Carboxin........................................................       5234-68-4
Carbophenothion.................................................        786-19-6
Chlordane\3\ \5\................................................         57-74-9
bis(2-Chloroethyl) ether \3\ \4\................................        111-44-4             5.7            17.1
Chloroneb.......................................................       2675-77-6
4-Chloroaniline.................................................        106-47-8
Chlorobenzilate.................................................        510-15-6
Chlorfenvinphos.................................................        470-90-6
4-Chloro-2-methylaniline........................................         95-69-2
3-(Chloromethyl)pyridine hydrochloride..........................       6959-48-4
4-Chloro-2-nitroaniline.........................................         89-63-4
Chlorpropham....................................................        101-21-3
Chlorothalonil..................................................       1897-45-6
1-Chloronaphthalene.............................................         90-13-1
3-Chloronitribenzene............................................        121-73-3
4-Chloro-1,2-phenylenediamine...................................         95-83-0
4-Chloro-1,3-phenylenediamine...................................       5131-60-2
2-Chlorobiphenyl................................................       2051-60-7
Chlorpyrifos....................................................       2921-88-2
Coumaphos.......................................................         56-72-4
m+p-Cresol......................................................      65794-96-9
o-Cresol........................................................         95-48-7
p-Cresidine.....................................................        120-71-8
Crotoxyphos.....................................................       7700-17-6
2-Cyclohexyl-4,6-dinitro-phenol.................................        131-89-5
Cyanazine.......................................................      21725-46-2
Cycloate........................................................       1134-23-2
p-Cymene........................................................         99-87-6
Dacthal (DCPA)..................................................       1861-32-1
4,4'-DDD \3\....................................................         72-54-8             2.8             8.4
4,4'-DDE \3\....................................................         72-55-9             5.6            16.8
4,4'-DDT \3\....................................................         50-29-3             4.7            14.1
Demeton-O.......................................................        298-03-3
Demeton-S.......................................................        126-75-0
Diallate (cis or trans).........................................       2303-16-4
2,4-Diaminotoluene..............................................         95-80-7
Diazinon........................................................        333-41-5
Dibenz(a,j)acridine.............................................        224-42-0
Dibenzofuran....................................................        132-64-9
Dibenzo(a,e)pyrene..............................................        192-65-4
Dibenzothiophene................................................        132-65-0
1,2-Dibromo-3-chloropropane.....................................         96-12-8
3,5-Dibromo-4-hydroxybenzonitrile...............................       1689-84-5
2,6-Di-tert-butyl-p-benzoquinone................................        719-22-2
Dichlone........................................................        117-80-6
2,3-Dichloroaniline.............................................        608-27-5
2,3-Dichlorobiphenyl............................................      16605-91-7
2,6-Dichloro-4-nitroaniline.....................................         99-30-9
2,3-Dichloronitrobenzene........................................       3209-22-1
1,3-Dichloro-2-propanol.........................................         96-23-1
2,6-Dichlorophenol..............................................        120-83-2
Dichlorvos......................................................         62-73-7
Dicrotophos.....................................................        141-66-2
Dieldrin \3\....................................................         60-57-1             2.5             7.5
1,2:3,4-Diepoxybutane...........................................       1464-53-5
Di(2-ethylhexyl) adipate........................................        103-23-1
Diethylstilbestrol..............................................         56-53-1
Diethyl sulfate.................................................         64-67-5
Dilantin (5,5-Diphenylhydantoin)................................         57-41-0
Dimethoate......................................................         60-51-5
3,3'-Dimethoxybenzidine.........................................        119-90-4
Dimethylaminoazobenzene.........................................         60-11-7
7,12-Dimethylbenz(a)anthracene..................................         57-97-6
3,3'-Dimethylbenzidine..........................................        119-93-7
N,N-Dimethylformamide...........................................         68-12-2
3,6-Dimethylphenathrene.........................................       1576-67-6
alpha, alpha-Dimethylphenethylamine.............................        122-09-8

Dimethyl sulfone................................................         67-71-0
1,2-Dinitrobenzene..............................................        528-29-0
1,3-Dinitrobenzene..............................................         99-65-0
1,4-Dinitrobenzene..............................................        100-25-4
Dinocap.........................................................      39300-45-3
Dinoseb.........................................................         88-85-7
Diphenylamine...................................................        122-39-4
Diphenyl ether..................................................        101-84-8
1,2-Diphenylhydrazine...........................................        122-66-7
Diphenamid......................................................        957-51-7
Diphenyldisulfide...............................................        882-33-7
Disulfoton......................................................        298-04-4
Disulfoton sulfoxide............................................       2497-07-6
Disulfoton sulfone..............................................       2497-06-5
Endosulfan I \3\ \4\............................................        959-98-8
Endosulfan II \3\ \4\...........................................      33213-65-9
Endosulfan sulfate \3\..........................................       1031-07-8             5.6            16.8
Endrin \3\ \4\..................................................         72-20-8
Endrin aldehyde \3\ \4\.........................................       7421-93-4
Endrin ketone \3\ \4\...........................................      53494-70-5
EPN.............................................................       2104-64-5
EPTC............................................................        759-94-4
Ethion..........................................................        563-12-2
Ethoprop........................................................      13194-48-4
Ethyl carbamate.................................................         51-79-6
Ethyl methanesulfonate..........................................         65-50-0
Ethylenethiourea................................................         96-45-7
Etridiazole.....................................................       2593-15-9
Ethynylestradiol-3-methyl ether.................................         72-33-3
Famphur.........................................................         52-85-7
Fenamiphos......................................................      22224-92-6
Fenarimol.......................................................      60168-88-9
Fensulfothion...................................................        115-90-2
Fenthion........................................................         55-38-9
Fluchloralin....................................................      33245-39-5
Fluridone.......................................................      59756-60-4
Heptachlor \3\..................................................         76-44-8             1.9             5.7
Heptachlor epoxide \3\..........................................       1024-57-3             2.2             6.6
2,2',3,3',4,4',6-Heptachlorobiphenyl............................      52663-71-5
2,2',4,4',5',6-Hexachlorobiphenyl...............................      60145-22-4
Hexachlorocyclopentadiene \3\ \4\...............................         77-47-4
Hexachlorophene.................................................         70-30-4
Hexachloropropene...............................................       1888-71-7
Hexamethylphosphoramide.........................................        680-31-9
Hexanoic acid...................................................        142-62-1
Hexazinone......................................................      51235-04-2
Hydroquinone....................................................        123-31-9
Isodrin.........................................................        465-73-6
2-Isopropylnapthalene...........................................       2027-17-0
Isosafrole......................................................        120-58-1
Kepone..........................................................        143-50-0
Leptophos.......................................................      21609-90-5
Longifolene.....................................................        475-20-7
Malachite green.................................................        569-64-2
Malathion.......................................................        121-75-5
Maleic anhydride................................................        108-31-6
Merphos.........................................................        150-50-5
Mestranol.......................................................         72-33-3
Methapyrilene...................................................         91-80-5
Methoxychlor....................................................         72-43-5
2-Methylbenzothioazole..........................................        120-75-2
3-Methylcholanthrene............................................         56-49-5
4,4'-Methylenebis(2-chloroaniline)..............................        101-14-4
4,4'-Methylenebis(N,N-dimethylaniline)..........................        101-61-1
4,5-Methylenephenanthrene.......................................        203-64-5
1-Methylfluorene................................................       1730-37-6
Methyl methanesulfonate.........................................         66-27-3
2-Methylnaphthalene.............................................         91-57-6
Methylparaoxon..................................................        950-35-6
Methyl parathion................................................        298-00-0
1-Methylphenanthrene............................................        832-69-9
2-(Methylthio)benzothiazole.....................................        615-22-5

Metolachlor.....................................................       5218-45-2
Metribuzin......................................................      21087-64-9
Mevinphos.......................................................       7786-34-7
Mexacarbate.....................................................        315-18-4
MGK 264.........................................................        113-48-4
Mirex...........................................................       2385-85-5
Molinate........................................................       2212-67-1
Monocrotophos...................................................       6923-22-4
Naled...........................................................        300-76-5
Napropamide.....................................................      15299-99-7
1,4-Naphthoquinone..............................................        130-15-4
1-Naphthylamine.................................................        134-32-7
2-Naphthylamine.................................................         91-59-8
1,5-Naphthalenediamine..........................................       2243-62-1
Nicotine........................................................         54-11-5
5-Nitroacenaphthene.............................................        602-87-9
2-Nitroaniline..................................................         88-74-4
3-Nitroaniline..................................................         99-09-2
4-Nitroaniline..................................................        100-01-6
5-Nitro-o-anisidine.............................................         99-59-2
4-Nitrobiphenyl.................................................         92-93-3
Nitrofen........................................................       1836-75-5
5-Nitro-o-toluidine.............................................         99-55-8
Nitroquinoline-1-oxide..........................................         56-57-5
N-Nitrosodi-n-butylamine \4\....................................        924-16-3
N-Nitrosodiethylamine \4\.......................................         55-18-5
N-Nitrosodimethylamine \3\ \4\..................................         62-75-9
N-Nitrosodiphenylamine \3\ \4\..................................         86-30-6
N-Nitrosomethylethylamine \4\...................................      10595-95-6
N-Nitrosomethylphenylamine \4\..................................        614-00-6
N-Nitrosomorpholine \4\.........................................         59-89-2
N-Nitrosopiperidine \4\.........................................        100-75-5
N-Nitrosopyrrolidine \4\........................................        930-55-2
trans-Nonachlor.................................................      39765-80-5
Norflurazon.....................................................      27314-13-2
2,2',3,3',4,5',6,6'-Octachlorobiphenyl..........................      40186-71-8
Octamethyl pyrophosphoramide....................................        152-16-9
4,4'-Oxydianiline...............................................        101-80-4
Parathion.......................................................         56-38-2
PCB-1016 \3\ \5\................................................      12674-11-2
PCB-1221 \3\ \5\................................................      11104-28-2              30              90
PCB-1232 \3\ \5\................................................      11141-16-5
PCB-1242 \3\ \5\................................................      53469-21-9
PCB-1248 \3\ \5\................................................      12672-29-6
PCB-1254 \3\ \5\................................................      11097-69-1              36             108
PCB-1260 \3\ \5\................................................      11098-82-5
PCB-1268 \3\ \5\................................................      11100-14-4
Pebulate........................................................       1114-71-2
Pentachlorobenzene..............................................        608-93-5
Pentachloronitrobenzene.........................................         82-68-8
2,2',3,4',6-Pentachlorobiphenyl.................................      68194-05-8
Pentachloroethane...............................................         76-01-7
Pentamethylbenzene..............................................        700-12-9
Perylene........................................................        198-55-0
Phenacetin......................................................         62-44-2
cis-Permethrin..................................................      61949-76-6
trans-Permethrin................................................      61949-77-7
Phenobarbital...................................................         50-06-6
Phenothiazene...................................................         92-84-2
1,4-Phenylenediamine............................................        624-18-0
1-Phenylnaphthalene.............................................        605-02-7
2-Phenylnaphthalene.............................................        612-94-2
Phorate.........................................................        298-02-2
Phosalone.......................................................       2310-18-0
Phosmet.........................................................        732-11-6
Phosphamidon....................................................      13171-21-6
Phthalic anhydride..............................................         85-44-9
alpha-Picoline (2-Methylpyridine)...............................        109-06-8
Piperonyl sulfoxide.............................................        120-62-7
Prometon........................................................       1610-18-0
Prometryn.......................................................       7287-19-6
Pronamide.......................................................      23950-58-5

Propachlor......................................................       1918-16-7
Propazine.......................................................        139-40-2
Propylthiouracil................................................         51-52-5
Pyridine........................................................        110-86-1
Resorcinol (1,3-Benzenediol)....................................        108-46-3
Safrole.........................................................         94-59-7
Simazine........................................................        122-34-9
Simetryn........................................................       1014-70-6
Squalene........................................................       7683-64-9
Stirofos........................................................      22248-79-9
Strychnine......................................................         57-24-9
Styrene.........................................................        100-42-5
Sulfallate......................................................         95-06-7
Tebuthiuron.....................................................      34014-18-1
Terbacil........................................................       5902-51-2
Terbufos........................................................      13071-79-9
Terbutryn.......................................................        886-50-0
alpha-Terpineol.................................................         98-55-5
1,2,4,5-Tetrachlorobenzene......................................         95-94-3
2,2',4,4'-Tetrachlorobiphenyl...................................       2437-79-8
2,3,7,8-Tetrachlorodibenzo-p-dioxin.............................       1746-01-6
2,3,4,6-Tetrachlorophenol.......................................         58-90-2
Tetrachlorvinphos...............................................      22248-79-9
Tetraethyl dithiopyrophosphate..................................       3689-24-5
Tetraethyl pyrophosphate........................................        107-49-3
Thianaphthene (2,3-Benzothiophene)..............................         95-15-8
Thioacetamide...................................................         62-55-5
Thionazin.......................................................        297-97-2
Thiophenol (Benzenethiol).......................................        108-98-5
Thioxanthone....................................................        492-22-8
Toluene-1,3-diisocyanate........................................      26471-62-5
Toluene-2,4-diisocyanate........................................        584-84-9
o-Toluidine.....................................................         95-53-4
Toxaphene \3\ \5\...............................................       8001-35-2
Triadimefon.....................................................      43121-43-3
1,2,3-Trichlorobenzene..........................................         87-61-6
2,4,5-Trichlorobiphenyl.........................................      15862-07-4
2,3,6-Trichlorophenol...........................................        933-75-5
2,4,5-Trichlorophenol...........................................         95-95-4
Tricyclazole....................................................      41814-78-2
Trifluralin.....................................................       1582-09-8
1,2,3-Trimethoxybenzene.........................................        634-36-6
2,4,5-Trimethylaniline..........................................        137-17-7
Trimethyl phosphate.............................................        512-56-1
Triphenylene....................................................        217-59-4
Tripropyleneglycolmethyl ether..................................      20324-33-8
1,3,5-Trinitrobenzene...........................................         99-35-4
Tris(2,3-dibromopropyl) phosphate...............................        126-72-7
Tri-p-tolyl phosphate...........................................         78-32-0
O,O,O-Triethyl phosphorothioate.................................        126-68-1
Trithiane.......................................................        291-29-4
Vernolate.......................................................       1929-77-7
----------------------------------------------------------------------------------------------------------------
\1\ Compounds that have been demonstrated amenable to extraction and gas chromatography.
\2\ Determine each analyte in the fraction that gives the most accurate result.
\3\ Priority Pollutant (40 CFR part 423, appendix A).
\4\ See Section 1.2.
\5\ These compounds are mixtures of various isomers.
\6\ MDL values from the 1984 promulgated version of Method 624.
\7\ ML = Minimum Level--see Glossary for definition and derivation.

                               Table 4--Chromatographic Conditions and Characteristic m/z's for Base/Neutral Extractables
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Characteristic m/z's
                                                                Retention  -----------------------------------------------------------------------------
                           Analyte                             time  (sec)        Electron impact ionization                 Chemical ionization
                                                                   \1\     -----------------------------------------------------------------------------
                                                                              Primary       Second       Second      Methane      Methane      Methane
--------------------------------------------------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine.......................................          385           42           74           44
bis(2-Chloroethyl) ether.....................................          704           93           63           95           63          107          109
bis(2-Chloroisopropyl) ether.................................          799           45           77           79           77          135          137
Hexachloroethane.............................................          823          117          201          199          199          201          203

N-Nitrosodi-n-propylamine....................................          830          130           42          101
Nitrobenzene.................................................          849           77          123           65          124          152          164
Isophorone...................................................          889           82           95          138          139          167          178
bis(2-Chloroethoxy) methane..................................          939           93           95          123           65          107          137
1,2,4-Trichlorobenzene.......................................          958          180          182          145          181          183          209
Naphthalene..................................................          967          128          129          127          129          157          169
Hexachlorobutadiene..........................................         1006          225          223          227          223          225          227
Hexachlorocyclopentadiene....................................         1142          237          235          272          235          237          239
2-Chloronaphthalene..........................................         1200          162          164          127          163          191          203
Acenaphthylene...............................................         1247          152          151          153          152          153          181
Dimethyl phthalate...........................................         1273          163          194          164          151          163          164
2,6-Dinitrotoluene...........................................         1300          165           89          121          183          211          223
Acenaphthene.................................................         1304          154          153          152          154          155          183
2,4-Dinitrotoluene...........................................         1364          165           63          182          183          211          223
Fluorene.....................................................         1401          166          165          167          166          167          195
4-Chlorophenyl phenyl ether..................................         1409          204          206          141
Diethyl phthalate............................................         1414          149          177          150          177          223          251
N-Nitrosodiphenylamine.......................................         1464          169          168          167          169          170          198
4-Bromophenyl phenyl ether...................................         1498          248          250          141          249          251          277
alpha-BHC....................................................         1514          183          181          109
Hexachlorobenzene............................................         1522          284          142          249          284          286          288
beta-BHC.....................................................         1544          183          181          109
gamma-BHC....................................................         1557          181          183          109
Phenanthrene.................................................         1583          178          179          176          178          179          207
Anthracene...................................................         1592          178          179          176          178          179          207
delta-BHC....................................................         1599          183          109          181
Heptachlor...................................................         1683          100          272          274
Di-n-butyl phthalate.........................................         1723          149          150          104          149          205          279
Aldrin.......................................................         1753           66          263          220
Fluoranthene.................................................         1817          202          101          100          203          231          243
Heptachlor epoxide...........................................         1820          353          355          351
gamma-Chlordane..............................................         1834          373          375          377
Pyrene.......................................................         1852          202          101          100          203          231          243
Benzidine \2\................................................         1853          184           92          185          185          213          225
alpha-Chlordane..............................................         1854          373          375          377
Endosulfan I.................................................         1855          237          339          341
4,4'-DDE.....................................................         1892          246          248          176
Dieldrin.....................................................         1907           79          263          279
Endrin.......................................................         1935           81          263           82
Endosulfan II................................................         2014          237          339          341
4,4'-DDD.....................................................         2019          235          237          165
Endrin aldehyde..............................................         2031           67          345          250
Butyl benzyl phthalate.......................................         2060          149           91          206          149          299          327
Endosulfan sulfate...........................................         2068          272          387          422
4,4'-DDT.....................................................         2073          235          237          165
Chrysene.....................................................         2083          228          226          229          228          229          257
3,3'-Dichlorobenzidine.......................................         2086          252          254          126
Benzo(a)anthracene...........................................         2090          228          229          226          228          229          257
bis(2-Ethylhexyl) phthalate..................................         2124          149          167          279          149
Di-n-octyl phthalate.........................................         2240          149           43           57
Benzo(b)fluoranthene.........................................         2286          252          253          125          252          253          281
Benzo(k)fluoranthene.........................................         2293          252          253          125          252          253          281
Benzo(a)pyrene...............................................         2350          252          253          125          252          253          281
Indeno(1,2,3-cd) pyrene......................................         2650          276          138          277          276          277          305
Dibenz(a,h)anthracene........................................         2660          278          139          279          278          279          307
Benzo(ghi)perylene...........................................         2750          276          138          277          276          277          305
Toxaphene....................................................  ...........          159          231          233
PCB 1016.....................................................  ...........          224          260          294
PCB 1221.....................................................  ...........          190          224          260
PCB 1232.....................................................  ...........          190          224          260
PCB 1242.....................................................  ...........          224          260          294
PCB 1248.....................................................  ...........          294          330          262
PCB 1254.....................................................  ...........          294          330          362
PCB 1260.....................................................  ...........          330          362          394
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Column: 30 m x 0.25 mm ID; 94% methyl, 5% phenyl, 1% vinyl bonded phase fused silica capillary.
Conditions: 5 min at 30 [deg]C; 30-280 at 8 [deg]C per min; isothermal at 280 [deg]C until benzo(ghi)perylene elutes.
Gas velocity: 30 cm/sec at 30 [deg]C (at constant pressure).
\2\ See Section 1.2; included for tailing factor testing.

                                   Table 5--Chromatographic Conditions and Characteristic m/z's for Acid Extractables
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Characteristic m/z's
                                                                Retention  -----------------------------------------------------------------------------
                           Analyte                             time  (sec)        Electron impact ionization                 Chemical ionization
                                                                   \1\     -----------------------------------------------------------------------------
                                                                              Primary       Second       Second      Methane      Methane      Methane
--------------------------------------------------------------------------------------------------------------------------------------------------------
2-Chlorophenol...............................................          705          128           64          130          129          131          157
Phenol.......................................................          700           94           65           66           95          123          135
2-Nitrophenol................................................          900          139           65          109          140          168          122
2,4-Dimethylphenol...........................................          924          122          107          121          123          151          163
2,4-Dichlorophenol...........................................          947          162          164           98          163          165          167
4-Chloro-3-methylphenol......................................         1091          142          107          144          143          171          183
2,4,6-Trichlorophenol........................................         1165          196          198          200          197          199          201
2,4-Dinitrophenol............................................         1325          184           63          154          185          213          225
4-Nitrophenol................................................         1354           65          139          109          140          168          122
2-Methyl-4,6-dinitrophenol...................................         1435          198          182           77          199          227          239
Pentachlorophenol............................................         1561          266          264          268          267          265          269
--------------------------------------------------------------------------------------------------------------------------------------------------------
Column: 30 m x 0.25 mm ID; 94% methyl, 5% phenyl, 1% vinyl bonded phase fused silica capillary.
Conditions: 5 min at 30 [deg]C; 30-250 at 8 [deg]C per min; isothermal at 280 [deg]C until pentachlorophenol elutes.
Gas velocity: 30 cm/sec at 30 [deg]C (at constant pressure).

                                 Table 6--QC Acceptance Criteria--Method 625 \1\
----------------------------------------------------------------------------------------------------------------
                                                                           Range for X   Range for
                    Analyte                      Range for Q  Limit for s     (%) \3\    P, Ps (%)    Limit for
                                                   (%) \2\      (%) \3\                     \3\        RPD (%)
----------------------------------------------------------------------------------------------------------------
Acenaphthene...................................       70-130           29       60-132       47-145           48
Acenaphthylene.................................       60-130           45       54-126       33-145           74
Aldrin.........................................        7-152           39        7-152        D-166           81
Anthracene.....................................       58-130           40       43-120       27-133           66
Benzo(a)anthracene.............................       42-133           32       42-133       33-143           53
Benzo(b)fluoranthene...........................       42-140           43       42-140       24-159           71
Benzo(k)fluoranthene...........................       25-146           38       25-146       11-162           63
Benzo(a)pyrene.................................       32-148           43       32-148       17-163           72
Benzo(ghi)perylene.............................       13-195           61        D-195        D-219           97
Benzyl butyl phthalate.........................       43-140           36        D-140        D-152           60
beta-BHC.......................................       42-131           37       42-131       24-149           61
delta-BHC......................................        D-130           77        D-120        D-120          129
bis(2-Chloroethyl)ether........................       52-130           65       43-126       12-158          108
bis(2-Chloroethoxy)methane.....................       52-164           32       49-165       33-184           54
bis(2-Chloroisopropyl) ether...................       63-139           46       63-139       36-166           76
bis(2-Ethylhexyl) phthalate....................       43-137           50       29-137        8-158           82
4-Bromophenyl phenyl ether.....................       70-130           26       65-120       53-127           43
2-Chloronaphthalene............................       70-130           15       65-120       60-120           24
4-Chlorophenyl phenyl ether....................       57-145           36       38-145       25-158           61
Chrysene.......................................       44-140           53       44-140       17-168           87
4,4'-DDD.......................................        D-135           56        D-135        D-145           93
4,4'-DDE.......................................       19-130           46       19-120        4-136           77
4,4'-DDT.......................................        D-171           81        D-171        D-203          135
Dibenz(a,h)anthracene..........................       13-200           75        D-200        D-227          126
Di-n-butyl phthalate...........................       52-130           28        8-120        1-120           47
3,3'-Dichlorobenzidine.........................       18-213           65        8-213        D-262          108
Dieldrin.......................................       70-130           38       44-119       29-136           62
Diethyl phthalate..............................       47-130           60        D-120        D-120          100
Dimethyl phthalate.............................       50-130          110        D-120        D-120          183
2,4-Dinitrotoluene.............................       53-130           25       48-127       39-139           42
2,6-Dinitrotoluene.............................       68-137           29       68-137       50-158           48
Di-n-octyl phthalate...........................       21-132           42       19-132        4-146           69
Endosulfan sulfate.............................        D-130           42        D-120        D-120           70
Endrin aldehyde................................        D-189           45        D-189        D-209           75
Fluoranthene...................................       47-130           40       43-121       26-137           66
Fluorene.......................................       70-130           23       70-120       59-121           38
Heptachlor.....................................        D-172           44        D-172        D-192           74
Heptachlor epoxide.............................       70-130           61       71-120       26-155          101
Hexachlorobenzene..............................       38-142           33        8-142        D-152           55
Hexachlorobutadiene............................       68-130           38       38-120       24-120           62
Hexachloroethane...............................       55-130           32       55-120       40-120           52
Indeno(1,2,3-cd)pyrene.........................       13-151           60        D-151        D-171           99
Isophorone.....................................       52-180           56       47-180       21-196           93
Naphthalene....................................       70-130           39       36-120       21-133           65
Nitrobenzene...................................       54-158           37       54-158       35-180           62
N-Nitrosodi-n-propylamine......................       59-170           52       14-198        D-230           87
PCB-1260.......................................       19-130           77       19-130        D-164          128

Phenanthrene...................................       67-130           24       65-120       54-120           39
Pyrene.........................................       70-130           30       70-120       52-120           49
1,2,4-Trichlorobenzene.........................       61-130           30       57-130       44-142           50
4-Chloro-3-methylphenol........................       68-130           44       41-128       22-147           73
2-Chlorophenol.................................       55-130           37       36-120       23-134           61
2,4-Dichlorophenol.............................       64-130           30       53-122       39-135           50
2,4-Dimethylphenol.............................       58-130           35       42-120       32-120           58
2,4-Dinitrophenol..............................       39-173           79        D-173        D-191          132
2-Methyl-4,6-dinitrophenol.....................       56-130          122       53-130        D-181          203
2-Nitrophenol..................................       61-163           33       45-167       29-182           55
4-Nitrophenol..................................       35-130           79       13-129        D-132          131
Pentachlorophenol..............................       42-152           52       38-152       14-176           86
Phenol.........................................       48-130           39       17-120        5-120           64
2,4,6-Trichlorophenol..........................       69-130           35       52-129       37-144           58
----------------------------------------------------------------------------------------------------------------
\1\ Acceptance criteria are based upon method performance data in Table 7 and from EPA Method 1625. Where
  necessary, limits for recovery have been broadened to assure applicability to concentrations below those used
  to develop Table 7.
\2\ Test concentration = 100 [mu]g/mL.
\3\ Test concentration = 100 [mu]g/L.
Q = Calibration verification (Sections 7.3.1 and 13.4).
s = Standard deviation for four recovery measurements in the DOC test (Section 8.2.4).
X = Average recovery for four recovery measurements in the DOC test (Section 8.2.4).
P, Ps = MS/MSD recovery (Section 8.3.2, Section 8.4.2).
RPD = MS/MSD relative percent difference (RPD; Section 8.3.3).
D = Detected; result must be greater than zero.

                 Table 7--Precision and Recovery as Functions of Concentration--Method 625 \ 1\
----------------------------------------------------------------------------------------------------------------
                                                                    Single analyst
              Analyte                 Recovery, X'  ([mu]g/L)   precision, sr'  ([mu]g/   Overall  precision, S'
                                                                          L)                    ([mu]g/L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene.......................  0.96C+0.19..............  0.15 x -0.12............  0.21 x -0.67
Acenaphthylene.....................  0.89C+0.74..............  0.24 x -1.06............  0.26 x -0.54
Aldrin.............................  0.78C+1.66..............  0.27 x -1.28............  0.43 x +1.13
Anthracene.........................  0.80C+0.68..............  0.21 x -0.32............  0.27 x -0.64
Benzo(a)anthracene.................  0.88C-0.60..............  0.15 x +0.93............  0.26 x -0.28
Benzo(b)fluoranthene...............  0.93C-1.80..............  0.22 x +0.43............  0.29 x +0.96
Benzo(k)fluoranthene...............  0.87C-1.56..............  0.19 x +1.03............  0.35 x +0.40
Benzo(a)pyrene.....................  0.90C-0.13..............  0.22 x +0.48............  0.32 x +1.35
Benzo(ghi)perylene.................  0.98C-0.86..............  0.29 x +2.40............  0.51 x -0.44
Benzyl butyl phthalate.............  0.66C-1.68..............  0.18 x +0.94............  0.53 x +0.92
beta-BHC...........................  0.87C-0.94..............  0.20 x -0.58............  0.30 x -1.94
delta-BHC..........................  0.29C-1.09..............  0.34 x +0.86............  0.93 x -0.17
bis(2-Chloroethyl)ether............  0.86C-1.54..............  0.35 x -0.99............  0.35 x +0.10
bis(2-Chloroethoxy)methane.........  1.12C-5.04..............  0.16 x +1.34............  0.26 x +2.01
bis(2-Chloroisopropyl)ether........  1.03C-2.31..............  0.24 x +0.28............  0.25 x +1.04
bis(2-Ethylhexyl)phthalate.........  0.84C-1.18..............  0.26 x +0.73............  0.36 x +0.67
4-Bromophenyl phenyl ether.........  0.91C-1.34..............  0.13 x +0.66............  0.16 x +0.66
2-Chloronaphthalene................  0.89C+0.01..............  0.07 x +0.52............  0.13 x +0.34
4-Chlorophenyl phenyl ether........  0.91C+0.53..............  0.20 x -0.94............  0.30 x -0.46
Chrysene...........................  0.93C-1.00..............  0.28 x +0.13............  0.33 x -0.09
4,4'-DDD...........................  0.56C-0.40..............  0.29 x -0.32............  0.66 x -0.96
4,4'-DDE...........................  0.70C-0.54..............  0.26 x -1.17............  0.39 x -1.04
4,4'-DDT...........................  0.79C-3.28..............  0.42 x +0.19............  0.65 x -0.58
Dibenz(a,h)anthracene..............  0.88C+4.72..............  0.30 x +8.51............  0.59 x +0.25
Di-n-butyl phthalate...............  0.59C+0.71..............  0.13 x +1.16............  0.39 x +0.60
3,3'-Dichlorobenzidine.............  1.23C-12.65.............  0.28 x +7.33............  0.47 x +3.45
Dieldrin...........................  0.82C-0.16..............  0.20 x -0.16............  0.26 x -0.07
Diethyl phthalate..................  0.43C+1.00..............  0.28 x +1.44............  0.52 x +0.22
Dimethyl phthalate.................  0.20C+1.03..............  0.54 x +0.19............  1.05 x -0.92
2,4-Dinitrotoluene.................  0.92C-4.81..............  0.12 x +1.06............  0.21 x +1.50
2,6-Dinitrotoluene.................  1.06C-3.60..............  0.14 x +1.26............  0.19 x +0.35
Di-n-octyl phthalate...............  0.76C-0.79..............  0.21 x +1.19............  0.37 x +1.19
Endosulfan sulfate.................  0.39C+0.41..............  0.12 x +2.47............  0.63 x -1.03
Endrin aldehyde....................  0.76C-3.86..............  0.18 x +3.91............  0.73 x -0.62
Fluoranthene.......................  0.81C+1.10..............  0.22 x +0.73............  0.28 x -0.60
Fluorene...........................  0.90C-0.00..............  0.12 x +0.26............  0.13 x +0.61
Heptachlor.........................  0.87C-2.97..............  0.24 x -0.56............  0.50 x -0.23
Heptachlor epoxide.................  0.92C-1.87..............  0.33 x -0.46............  0.28 x +0.64
Hexachlorobenzene..................  0.74C+0.66..............  0.18 x -0.10............  0.43 x -0.52

Hexachlorobutadiene................  0.71C-1.01..............  0.19 x +0.92............  0.26 x +0.49
Hexachloroethane...................  0.73C-0.83..............  0.17 x +0.67............  0.17 x +0.80
Indeno(1,2,3-cd)pyrene.............  0.78C-3.10..............  0.29 x +1.46............  0.50 x +0.44
Isophorone.........................  1.12C+1.41..............  0.27 x +0.77............  0.33 x +0.26
Naphthalene........................  0.76C+1.58..............  0.21 x -0.41............  0.30 x -0.68
Nitrobenzene.......................  1.09C-3.05..............  0.19 x +0.92............  0.27 x +0.21
N-Nitrosodi-n-propylamine..........  1.12C-6.22..............  0.27 x +0.68............  0.44 x +0.47
PCB-1260...........................  0.81C-10.86.............  0.35 x +3.61............  0.43 x +1.82
Phenanthrene.......................  0.87C-0.06..............  0.12 x +0.57............  0.15 x +0.25
Pyrene.............................  0.84C-0.16..............  0.16 x +0.06............  0.15 x +0.31
1,2,4-Trichlorobenzene.............  0.94C-0.79..............  0.15 x +0.85............  0.21 x +0.39
4-Chloro-3-methylphenol............  0.84C+0.35..............  0.23 x +0.75............  0.29 x +1.31
2-Chlorophenol.....................  0.78C+0.29..............  0.18 x +1.46............  0.28 x 0.97
2,4-Dichlorophenol.................  0.87C+0.13..............  0.15 x +1.25............  0.21 x +1.28
2,4-Dimethylphenol.................  0.71C+4.41..............  0.16 x +1.21............  0.22 x +1.31
2,4-Dinitrophenol..................  0.81C-18.04.............  0.38 x +2.36............  0.42 x +26.29
2-Methyl-4,6-Dinitrophenol.........  1.04C-28.04.............  0.05 x +42.29...........  0.26 x +23.10
2-Nitrophenol......................  1.07C-1.15..............  0.16 x +1.94............  0.27 x +2.60
4-Nitrophenol......................  0.61C-1.22..............  0.38 x +2.57............  0.44 x +3.24
Pentachlorophenol..................  0.93C+1.99..............  0.24 x +3.03............  0.30 x +4.33
Phenol.............................  0.43C+1.26..............  0.26 x +0.73............  0.35 x +0.58
2,4,6-Trichlorophenol..............  0.91C-0.18..............  0.16 x +2.22............  0.22 x +1.81
----------------------------------------------------------------------------------------------------------------
\1\ Regressions based on data from Reference 2
X' = Expected recovery for one or more measurements of a sample containing a concentration of C, in [mu]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of x, in
  [mu]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of x, in
  [mu]g/L.
C = True value for the concentration, in [mu]g/L.
x = Average recovery found for measurements of samples containing a concentration of C, in [mu]g/L.

           Table 8--Suggested Internal and Surrogate Standards
------------------------------------------------------------------------
                                        Range for surrogate recovery (%)
                                                       \1\
         Base/neutral fraction         ---------------------------------
                                          Calibration     Recovery from
                                          verification       samples
------------------------------------------------------------------------
Acenaphthalene-d8.....................           66-152           33-168
Acenaphthene-d10......................           71-141           30-180
Aniline-d5.
Anthracene-d10........................           58-171           23-142
Benzo(a)anthracene-d12................           28-357           22-329
Benzo(a)pyrene-d12....................           32-194           32-194
4-Chloroaniline-d4....................            1-145            1-145
bis(2-Chloroethyl) ether-d8...........           52-194           25-222
Chrysene-d12..........................           23-290           23-290
Decafluorobiphenyl.
4,4'-Dibromobiphenyl.
4,4'-Dibromooctafluorobiphenyl.
1,4-Dichlorobenzene-d4................           65-153           11-245
2,2'-Difluorobiphenyl.
Dimethyl phthalate-d6.................           47-211            1-500
Fluoranthene-d10......................           47-215           30-187
Fluorene-d10..........................           61-164           38-172
4-Fluoroaniline.
1-Fluoronaphthalene.
2-Fluoronaphthalene.
2-Methylnaphthalene-d10...............           50-150           50-150
Naphthalene-d8........................           71-141           22-192
Nitrobenzene-d5.......................           46-219           15-314
2,3,4,5,6-Pentafluorobiphenyl.
Perylene-d12.
Phenanthrene-d10......................           67-149           34-168
Pyrene-d10............................           48-210           28-196
Pyridine-d5.
------------------------------------------------------------------------
                              Acid fraction
------------------------------------------------------------------------
2-Chlorophenol-d4.....................           55-180           33-180
2,4-Dichlorophenol-d3.................           64-157           34-182
4,6-Dinitro-2-methylphenol-d2.........           56-177           22-307

2-Fluorophenol.
4-Methylphenol-d8.....................           25-111           25-111
2-Nitrophenol-d4......................           61-163           37-163
4-Nitrophenol-d4......................           35-287            6-500
Pentafluorophenol.
2-Perfluoromethylphenol.
Phenol-d5.............................           48-208            8-424
------------------------------------------------------------------------
\1\ Recovery from samples is the wider of the criteria in the CLP SOW
  for organics or in Method 1625.

     Table 9A--DFTPP Key m/z's and Abundance Criteria for Quadrupole
                             Instruments \1\
------------------------------------------------------------------------
  m/z                           Abundance criteria
------------------------------------------------------------------------
     51  30-60 percent of m/z 198.
     68  Less than 2 percent of m/z 69.
     70  Less than 2 percent of m/z 69.
    127  40-60 percent of base peak m/z 198.
    197  Less than 1 percent of m/z 198.
    198  Base peak, 100 percent relative abundance.
    199  5-9 percent of m/z 198.
    275  10-30 percent of m/z 198.
    365  Greater than 1 percent of m/z 198.
    441  Present but less than m/z 443.
    442  40-100 percent of m/z 198.
    443  17-23 percent of m/z 442.
------------------------------------------------------------------------
\1\ Criteria in these tables are for quadrupole and time-of-flight
  instruments. Alternative tuning criteria may be used for other
  instruments, provided method performance is not adversely affected.

   Table 9B--DFTPP Key m/z's and Abundance Criteria for Time-of-flight
                             Instruments \1\
------------------------------------------------------------------------
  m/z                           Abundance criteria
------------------------------------------------------------------------
     51  10-85 percent of the base peak.
     68  Less than 2 percent of m/z 69.
     70  Less than 2 percent of m/z 69.
    127  10-80 percent of the base peak.
    197  Less than 2 percent of Mass 198.
    198  Base peak, or greater than 50% of m/z 442.
    199  5-9 percent of m/z 198.
    275  10-60 percent of the base peak.
    365  Greater than 0.5 percent of m/z 198.
    441  Less than 150 percent of m/z 443.
    442  Base peak or greater than 30 percent of m/z 198.
    443  15-24 percent of m/z 442.
------------------------------------------------------------------------
\1\ Criteria in these tables are for quadrupole and time-of-flight
  instruments. Alternative tuning criteria may be used for other
  instruments, provided method performance is not adversely affected.

21. Figures

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[GRAPHIC] [TIFF OMITTED] TP19FE15.020

BILLING CODE 6560-50-C
22. Glossary
    These definitions and purposes are specific to this method but have
been conformed to common usage to the extent possible.
    22.1 Units of weight and measure and their abbreviations
    22.1.1 Symbols
[ordm]C degrees Celsius
[micro]g microgram
[micro]L microliter
< less than
> greater than
<= less than or equal to
% percent

    22.1.2 Abbreviations (in alphabetical order)

cm centimeter
g gram
h hour
ID inside diameter
in. inch
L liter
M Molecular ion
m mass or meter
mg milligram
min minute
mL milliliter
mm millimeter
ms millisecond
m/z mass-to-charge ratio
N normal; gram molecular weight of solute divided by hydrogen
equivalent of solute, per liter of solution
ng nanogram
pg picogram
ppb part-per-billion
ppm part-per-million
ppt part-per-trillion
psig pounds-per-square inch gauge

    22.2 Definitions and acronyms (in alphabetical order)
    Analyte--A compound or mixture of compounds (e.g., PCBs) tested for
by this method. The analytes are listed in Tables 1-3.
    Batch--See Extraction
    Blank--An aliquot of reagent water that is treated exactly as a
sample including exposure to all glassware, equipment, solvents,
reagents, internal standards, and surrogates that are used with
samples. The blank is used to determine if analytes or interferences
are present in the laboratory environment, the reagents, or the
apparatus.
    Calibration--The process of determining the relationship between
the output or response of a measuring instrument and the value of an
input standard. Historically, EPA has referred to a multi-point
calibration as the ``initial calibration,'' to differentiate it from a
single-point calibration verification.
    Calibration standard--A solution prepared from stock solutions and/
or a secondary standards and containing the analytes of interest,
surrogates, and internal standards. The calibration standard is used to
calibrate the response of the GC/MS instrument against analyte
concentration.
    Calibration verification standard--The mid-point calibration
standard used to verify calibration. See Sections 7.3 and 13.4.
    Descriptor--In SIM, the beginning and ending retention times for
the RT window, the m/z's sampled in the RT window, and the dwell time
at each m/z.
    Extracted ion current profile (EICP)--The line described by the
signal at a given m/z.
    Extraction Batch--A set of up to 20 field samples (not including QC
samples) started through the extraction process on a given 12-hour
shift (Section 3.1). Each extraction batch must be accompanied by a
blank (Section 8.5), a laboratory control

sample (LCS, Section 8.4), and a matrix spike and duplicate (MS/MSD;
Section 8.3), resulting in a minimum of five analyses (1 sample, 1
blank, 1 LCS, 1 MS, and 1 MSD) and a maximum of 24 analyses (20 field
samples, 1 blank, 1 LCS, 1 MS, and 1 MSD) for the batch. If greater
than 20 samples are to be extracted in a 12-hour shift, the samples
must be separated into extraction batches of 20 or fewer samples.
    Field Duplicates--Two samples collected at the same time and place
under identical conditions, and treated identically throughout field
and laboratory procedures. Results of analyses the field duplicates
provide an estimate of the precision associated with sample collection,
preservation, and storage, as well as with laboratory procedures.
    Field blank--An aliquot of reagent water or other reference matrix
that is placed in a sample container in the field, and treated as a
sample in all respects, including exposure to sampling site conditions,
storage, preservation, and all analytical procedures. The purpose of
the field blank is to determine if the field or sample transporting
procedures and environments have contaminated the sample.
    GC--Gas chromatograph or gas chromatography
    Internal standard--A compound added to an extract or standard
solution in a known amount and used as a reference for quantitation of
the analytes of interest and surrogates. In this method the internal
standards are stable isotopically labeled analogs of selected method
analytes (Table 8). Also see Internal standard quantitation.
    Internal standard quantitation--A means of determining the
concentration of an analyte of interest (Tables 1-3) by reference to a
compound not expected to be found in a sample.
    DOC--Initial demonstration of capability (Section 8.2); four
aliquots of reagent water spiked with the analytes of interest and
analyzed to establish the ability of the laboratory to generate
acceptable precision and recovery. A DOC is performed prior to the
first time this method is used and any time the method or
instrumentation is modified.
    Laboratory Control Sample (LCS; laboratory fortified blank; Section
8.4)--An aliquot of reagent water spiked with known quantities of the
analytes of interest and surrogates. The LCS is analyzed exactly like a
sample. Its purpose is to assure that the results produced by the
laboratory remain within the limits specified in this method for
precision and recovery.
    Laboratory fortified sample matrix--See Matrix spike
    Laboratory reagent blank--A blank run on laboratory reagents; e.g.,
methylene chloride (Section 11.1.5).
    Matrix spike (MS) and matrix spike duplicate (MSD) (laboratory
fortified sample matrix and duplicate)--Two aliquots of an
environmental sample to which known quantities of the analytes of
interest and surrogates are added in the laboratory. The MS/MSD are
prepared and analyzed exactly like a field sample. Their purpose is to
quantify any additional bias and imprecision caused by the sample
matrix. The background concentrations of the analytes in the sample
matrix must be determined in a separate aliquot and the measured values
in the MS/MSD corrected for background concentrations.
    May--This action, activity, or procedural step is neither required
nor prohibited.
    May not--This action, activity, or procedural step is prohibited.
    Method blank--See blank.
    Method detection limit (MDL)--A detection limit determined by the
procedure at 40 CFR 136, Appendix B. The MDLs determined by EPA in the
original version of the method are listed in Tables 1, 2 and 3. As
noted in Sec. 1.5, use the MDLs in Tables 1, 2, and 3 in conjunction
with current MDL data from the laboratory actually analyzing samples to
assess the sensitivity of this procedure relative to project objectives
and regulatory requirements (where applicable).
    Minimum level (ML)--The term ``minimum level'' refers to either the
sample concentration equivalent to the lowest calibration point in a
method or a multiple of the method detection limit (MDL), whichever is
higher. Minimum levels may be obtained in several ways: They may be
published in a method; they may be based on the lowest acceptable
calibration point used by a laboratory; or they may be calculated by
multiplying the MDL in a method, or the MDL determined by a laboratory,
by a factor of 3. For the purposes of NPDES compliance monitoring, EPA
considers the following terms to be synonymous: ``quantitation limit,''
``reporting limit,'' and ``minimum level.''
    MS--Mass spectrometer or mass spectrometry, or matrix spike (a QC
sample type).
    MSD--Matrix spike duplicate (a QC sample type).
    Must--This action, activity, or procedural step is required.
    m/z--The ratio of the mass of an ion (m) detected in the mass
spectrometer to the charge (z) of that ion.
    Preparation blank--See blank.
    Quality control check sample (QCS)--See Laboratory Control Sample.
    Reagent water--Water demonstrated to be free from the analytes of
interest and potentially interfering substances at the MDLs for the
analytes in this method.
    Regulatory compliance limit (or regulatory concentration limit)--A
limit on the concentration or amount of a pollutant or contaminant
specified in a nationwide standard, in a permit, or otherwise
established by a regulatory/control authority.
    Relative retention time (RRT)--The ratio of the retention time of
an analyte to the retention time of its associated internal standard.
RRT compensates for small changes in the GC temperature program that
can affect the absolute retention times of the analyte and internal
standard. RRT is a unitless quantity.
    Relative standard deviation (RSD)--The standard deviation times 100
divided by the mean. Also termed ``coefficient of variation.''
    RF--Response factor. See Section 7.2.2.
    RSD--See relative standard deviation.
    Safety Data Sheet (SDS)--Written information on a chemical's
toxicity, health hazards, physical properties, fire, and reactivity,
including storage, spill, and handling precautions that meet the
requirements of OSHA, 29 CFR 1910.1200(g) and appendix D to Sec.
1910.1200. United Nations Globally Harmonized System of Classification
and Labelling of Chemicals (GHS), third revised edition, United
Nations, 2009.
    Selected Ion Monitoring (SIM)--An MS technique in which a few m/z's
are monitored. When used with gas chromatography, the m/z's monitored
are usually changed periodically throughout the chromatographic run, to
correlate with the characteristic m/z's of the analytes, surrogates,
and internal standards as they elute from the chromatographic column.
The technique is often used to increase sensitivity and minimize
interferences.
    Signal-to-noise ratio (S/N)--The height of the signal as measured
from the mean (average) of the noise to the peak maximum divided by the
width of the noise.
    Should--This action, activity, or procedural step is suggested but
not required.
    SPE--Solid-phase extraction; an extraction technique in which an
analyte is extracted from an aqueous solution by passage over or
through a material capable of reversibly adsorbing the analyte. Also
termed liquid-solid extraction.

    Stock solution--A solution containing an analyte that is prepared
using a reference material traceable to EPA, the National Institute of
Science and Technology (NIST), or a source that will attest to the
purity, authenticity, and concentration of the standard.
    Surrogate--A compound unlikely to be found in a sample, and which
is spiked into sample in a known amount before extraction or other
processing, and is quantitated with the same procedures used to
quantify other sample components. The purpose of the surrogate is to
monitor method performance with each sample.
* * * * *
0
9. Revise Appendix B to part 136 to read as follows:

Appendix B to Part 136--Definition and Procedure for the Determination
of the Method Detection Limit--Revision 2

Definition

    The method detection limit (MDL) is defined as the minimum
measured concentration of a substance that can be reported with 99%
confidence that the measured concentration is distinguishable from
method blank results.

Scope and Application

    The MDL procedure is designed to be a straightforward technique
for estimation of the detection limit for a broad variety of
physical and chemical methods. The procedure requires a complete,
specific, and well defined analytical method. It is essential that
all sample processing steps used by the laboratory be included in
the determination of the method detection limit.

Procedure

    (1) Estimate the Initial MDL using one of the following:
    (a) The mean plus three times the standard deviation of a set of
method blanks.
    (b) The concentration value that corresponds to an instrument
signal/noise in the range of 3 to 5.
    (c) The concentration equivalent of three times the standard
deviation of replicate instrumental measurements of spiked blanks.
    (d) 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.
    (e) Instrumental limitations.
    (f) Previously determined MDL.
    It is recognized that the experience of the analyst is important
to this process. However, the analyst should include some or all of
the above considerations in the initial estimate of the MDL.
    (2) Determine the Initial MDL
    (a) Select a spiking level, typically 2-10 times the estimated
MDL in section 1. Spiking levels in excess of 10 times the estimated
detection limit may be required for analytes with very poor recovery
(e.g., an analyte with 10% recovery, spiked at 100 micrograms/L,
mean recovery, 10 micrograms/L; MDL may calculate at 3 micrograms/L.
So, in this case the spiking level is 33xMDL, but spiking lower may
result in no recovery at all).
    (b) Process a minimum of 7 spiked blank samples and 7 method
blank samples through all steps of the method, including any sample
preservation. Both preparation and analysis of these samples must
include at least three batches on three separate calendar dates.
Existing data may be used if compliant with the requirements for at
least 3 batches and generated within the last 2 years.
    (i) If there are multiple instruments that will be assigned the
same MDL, then the samples must be distributed across all of the
instruments.
    (ii) A minimum of two spiked samples and two method blank
samples prepared and analyzed on different calendar dates is
required for each instrument.
    (c) Evaluate the spiking level: If any result for any individual
analyte from the spiked blank samples does not meet the method
qualitative identification criteria or does not provide a numerical
result greater than zero then repeat the spikes at a higher
concentration. Qualitative identification criteria are a set of
rules or guidelines for establishing the identification or presence
of an analyte using a measurement system. Qualitative identification
does not ensure that quantitative results for the analyte can be
obtained.
    (d) Make all computations according to the defined method with
final results in the method reporting units.
    (i) Calculate the sample standard deviation (S) of the replicate
spiked blank measurements and the sample standard deviation of the
replicate method blank measurements from all instruments.
    (ii) Compute the MDLs (MDL based on spiked blanks) as
follows:

MDLS = t(n-1, 1-[vprop]=0.99) SS

Where:

MDLs = the method detection limit based on spiked blanks
t(n-1, 1-[alpha]=0.99) = the Student's t-value
appropriate for a the single tailed 99th percentile t statistic and
a standard deviation estimate with n-1 degrees of freedom. See Table
1.
Ss = sample standard deviation of the replicate spiked
blank sample analyses.

    (iii) Compute the MDLb (MDL based on method blanks) as
follows:
    (A) If none of the method blanks give numerical results for an
individual analyte, the MDLb does not apply. A numerical
result includes both positive and negative results, including results
below the current MDL, but not results of ND (not detected) commonly
observed when a peak is not present in chromatographic analysis.
    (B) If some (but not all) of the method blanks for an individual
analyte give numerical results, set the MDLb equal to the
highest method blank result. If more than 100 method blanks are
available, set MDLb to the level that is no less than the
99th percentile of the blank results. For ``n'' method blanks where n
>= 100, sort the method blanks in rank order. The (nx0.99) ranked
method blank result (round to the nearest whole number) is the
MDLb. For example, to find MDLb from a set of 164
method blanks where the highest ranked method blank results are . . .
1.5, 1.7, 1.9, 5.0, and 10, then 164x0.99 = 162.36 which rounds to the
162nd method blank result. Therefore, MDLb is 1.9 for n =
164 (10 is the 164th result, 5.0 is the 163rd result, and 1.9 is the
162nd result). Alternatively, you may use spreadsheet algorithms to
calculate the 99th percentile to interpolate between the ranks more
precisely.
    (C) If all of the method blanks for an individual analyte give
numerical results, calculate the MDLb as:

MDLb = XX + t(n-1, 1-[vprop]=0.99)
Sb

Where:

MDLb = the MDL based on method blanks
XX = mean of the method blank results
t(n-1, 1-[alpha]=0.99) = the Student's t-value
appropriate for the single tailed 99th percentile t statistic and a
standard deviation estimate with n-1 degrees of freedom. See
Addendum Table 1.
Sb = sample standard deviation of the replicate blank
sample analyses.

    (e) Set the greater of MDLs or MDLb as the
initial MDL.
    (3) Ongoing Data Collection
    (a) During any quarter in which samples are being analyzed, prepare
and analyze a minimum of two spiked blanks on each instrument, in
separate batches if available, using the same spiking concentration
used in Section 2. If any analytes are repeatedly not detected in the
quarterly spike sample analysis, this is an indication that the spiking
level is not high enough and should be adjusted upward.
    (b) Ensure that at least 7 spiked blanks and 7 method blanks are
completed for the annual verification.
    (c) At least once per year, re-evaluate the spiking level.
    (i) If more than 5% of the spiked blanks do not return positive
numerical results that meet all method qualitative identification
criteria, then the spiking level must be increased and the initial MDL
re-determined following the procedure in Section 2.
    (d) If the method is altered in a way that can be reasonably
expected to change the detection limit, then re-determine the initial
MDL according to Section 2, and the ongoing data collection restarted.
    (4) Ongoing Annual Verification
    (a) At least once per year, re-calculate MDLs and
MDLb from the collected spiked blank and method blank
results using the equations in section 2.
    (b) Include data generated within the last 2 years, but only data
with the same spiking level.

    (c) Include the initial MDL spiked blanks if within two years.
    (d) Only use data associated with acceptable calibrations and batch
QC. Include all routine data, with the exception of batches that are
rejected and the associated samples reanalyzed. If the method has been
altered in a way that can be reasonably expected to change the
detection limit, use only data collected after the change.
    (e) The verified MDL is the greater of the MDLs or
MDLb. If the verified MDL is within a factor of 3 of the
existing MDL, and fewer than 3% of the method blank results (for the
individual analyte) have numerical results above the existing MDL, then
the existing MDL may optionally be left unchanged. Otherwise, adjust
the MDL to the new verification MDL.
Addendum: Determination of the MDL For a Specific Matrix
    MDLs may be determined in specific sample matrices as well as in
reagent water.
    (1) Analyze the sample matrix to determine the native concentration
of the analyte(s) of interest.
    (2) If the native concentration is at a signal to noise ratio of
approximately 5-20, determine the matrix specific MDL according to
Section 2, ``Determine the initial MDL'' without spiking additional
analyte.
    (3) Calculate MDLb using method blanks, not the sample
matrix.
    (4) If the signal to noise is less than 5, the analyte(s) should be
spiked to obtain a concentration that will give results with a signal
to noise of approximately 10-20.
    (5) If the analytes(s) of interest have signal to noise greater
than approximately 20, then the resulting MDL is likely to be biased
high.

           Table 1--Single Tailed 99th Percentile t Statistic
------------------------------------------------------------------------
                                            Degrees of
          Number of  replicates           freedom  (n-1)   t (n-1, 0.99)
------------------------------------------------------------------------
7.......................................               6           3.143
8.......................................               7           2.998
9.......................................               8           2.896
10......................................               9           2.821
11......................................              10           2.764
16......................................              15           2.602
21......................................              20           2.528
26......................................              25           2.485
31......................................              30           2.457
61......................................              60           2.390
100.....................................             100           2.326
------------------------------------------------------------------------

Documentation
    The analytical method used must be specifically identified by
number or title and the MDL for each analyte expressed in the
appropriate method reporting units. Data and calculations used to
establish the MDL must be able to be reconstructed upon request.
    The sample matrix used to determine the MDL must also be identified
with MDL value. Document the mean spiked and recovered analyte levels
with the MDL.

[FR Doc. 2015-02841 Filed 2-18-15; 8:45 am]
BILLING CODE 6560-50-P