Appendix D to Part 136 -- Precision and Recovery Statements for Methods for Measuring Metals

Twenty-eight selected methods from "Methods for Chemical Analysis of Water and Wastes," EPA-600/4-79-020 (1979) have been subjected to interlaboratory method validation studies. The following precision and recovery statements are presented in this appendix and incorporated into part 136:

For Aluminum, Method 202.1 (Atomic Absorption, Direct Aspiration) replace the Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trace Methods in water by Atomic Absorption Spectroscopy (Direction Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June, 1986.

For a concentration range of 500-1200 μg/L

X=0.979(C)+6.16

S=0.066(X)+125

SR=0.086(X)+40.5

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Arsenic, Method 206.4 (Spectrophotometric-SDDC) add the following to the Precision and Accuracy Section:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June, 1986.

For a concentration range of 20-292 μg/L

X=0.850(C)−0.25

S=0.198(X)+5.93

SR=0.122(X)+3.10

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Cadmium, Method 213.1 (Atomic Absorption, Direct Aspiration) replace the Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June, 1986.

For a concentration range of 14-78 μg/L

X=0.919(C)+2.97

S=0.108(X)+5.08

SR=0.120(X)+0.89

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Chromium, Method 218.1 (Atomic Absorption, Direct Aspiration) replace the Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June 1986.

For a concentration range of 74-407 μg/L

X=0.976(C)+3.94

S=0.131(X)+4.26

SR=0.052(X)+3.01

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Copper, Method 220.1 (Atomic Absorption, Direct Aspiration) replace the Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June, 1986.

For concentration range 60-332 μg/L

X=0.963(C)+3.49

S=0.047(X)+12.3

SR=0.042(X)+4.60

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Iron, Method 236.1 (Atomic Absorption, Direct Aspiration) replace the Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trade Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June, 1986.

For concentration range 350-840 μg/L

X=0.999(C)−2.21

S=0.022(X)+41.0

SR=0.019(X)+21.2

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-Laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Lead, Method 239.1 (Atomic Absorption, Direct Aspiration) replace Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7 Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry"; National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June, 1986.

For concentration range of 84-367 μg/L

X=0.961(C)+13.8

S=0.028(C)+33.9

SR=0.011(X)+16.1

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Manganese, Method 243.1 (Atomic Absorption, Direct Aspiration) replace Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J.A. and Britton, P.W., June, 1986.

For concentration range 84-469 μg/L

X=0.987(C)−1.27

S=0.042(X)+8.95

SR=0.023(X)+4.90

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Zinc, Method 289.1 (Atomic Absorption, Direct Aspiration) replace the Precision and Accuracy Section with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water and a natural water or effluent of the analyst's choice. The digestion procedure was not specified. Results for the reagent water are given below. Results for other water types and study details are found in "USEPA Method Study 7, Analyses for Trace Methods in Water by Atomic Absorption Spectroscopy (Direct Aspiration) and Colorimetry", National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB86-208709/AS, Winter, J. A. and Britton, P. W., June, 1986.

For concentration range 56-310 μg/L

X=0.999(C)+0.033

S=0.078(X)+10.8

SR=0.049(X)+1.10

where:
    C=True Value for the Concentration, μg/L

    X=Mean Recovery, μg/L

    S=Multi-laboratory Standard Deviation, μg/L

    SR=Single-analyst Standard Deviation, μg/L

For Aluminum, Method 202.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques), "National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.46−125 μg/L

X=1.1579(C)−0.121

S=0.4286(X)−0.124

SR=0.2908(X)−0.082

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Antimony, Method 204.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual as modified by this method. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 10.50−240 μg/L

X=0.7219(C)−0.986

S=0.3732(X)+0.854

SR=0.1874(X)−0.461

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Arsenic, Method 206.2 (Atomic Absorption, Furnace Technique) add the following to the existing Precision and Accuracy statement:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 9.78−237 μg/L

X=0.9652(C)+2.112

S=0.1411(X)+1.873

SR=0.0464(X)+2.109

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Barium, Method 208.2 (Atomic Absorption, Furnace Technique) add the following to the existing Precision and Accuracy information:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 56.50-437 μg/L

X=0.8268(C)+59.459

S=0.2466(X)+6.436

SR=0.1393(X)−0.428

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Beryllium, Method 210.2 (Atomic Absorption, Furnace Technique) replace the existing Precision and Accuracy statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.45-11.4 μg/L

X=1.0682(C)−0.158

S=0.2167(X)+0.090

SR=0.1096(X)+0.061

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Cadmium, Method 213.2 (Atomic Absorption, Furnace Technique) add the following to the existing Precision and Accuracy information:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring System Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.43-12.5 μg/L
    X=0.9826(C)+0.171

S=0.2300(X)+0.045

SR=0.1031(X)+0.116

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Devision, μg/L

For Chromium, Method 218.2 (Atomic Absorption, Furnace Technique) add the following to the existing Precision and Accuracy Section:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161, Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 9.87-246 μg/L

X=0.9120(C)+0.234

S=0.1684(X)+0.852

SR=0.1469(X)+0.315

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Devision, μg/L

For Cobalt, Method 219.2 (Atomic Absorption, Furnace Technique), replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 21.10−461 μg/L

X=0.8875(C)+0.859

S=0.2481(X)−2.541

SR=0.0969(X)+0.134

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation,     μg/L

For Copper, Method 220.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.30−245 μg/L

X=0.9253(C)+0.010

S=0.2735(X)−0.058

SR=0.2197(X)−0.050

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation,     μg/L

For Iron, Method 236.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.37−455 μg/L

X=1.4494(C)−0.229

S=0.3611(X)−0.079

SR=0.3715(X)−0.161

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation,     μg/L

For Lead, Method 239.2 (Atomic Absorption, Furnace Technique) add the following to the existing Precisions and Accuracy Section:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 10.40−254 μg/L

X=0.9430(C)−0.504

S=0.2224(X)+0.507

SR=0.1931(X)−0.378

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation,     μg/L

For Manganese, Method 243.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL -- CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.42-666 μg/L

X=1.0480(C)+1.404

S=0.2001(X)+1.042

SR=0.1333(X)+0.680

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Nickel, Method 249.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL -- CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 26.20-482 μg/L

X=0.8812(C)+2.426

S=0.2475(X)+1.896

SR=0.1935(X)+1.315

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Selenium, Method 270.2 (Atomic Absorption, Furnace Technique) add the following to the existing Precision and Accuracy Section:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL -- CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 10.00-246 μg/L

X=0.9564(C)+0.476

S=0.1584(X)+0.878

SR=0.0772(X)+0.547

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Silver, Method 272.2 (Atomic Absorption, Furnace Technique) add the following to the existing Precision and Accuracy Section:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory -- Cincinnati (EMSL -- CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161. Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.45-56.5 μg/L

X=0.9470(C)+0.181

S=0.1805(X)+0.153

SR=0.1417(X)+0.039

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Thalliu, Method 279.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 10.00-252 μg/L.

X=0.8781(C)−0.715

S=0.1112(X)+0.669

SR=0.1005(X)+0.241

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation, μg/L

For Vanadium, Method 286.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 1.36-982 μg/L.

X=0.8486(C)+0.252

S=0.3323(X)−0.428

SR=0.1195(X)−0.121

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation,         μg/L

For Zinc, Method 289.2 (Atomic Absorption, Furnace Technique) replace the Precision and Accuracy Section statement with the following:

An interlaboratory study on metal analyses by this method was conducted by the Quality Assurance Branch (QAB) of the Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI). Synthetic concentrates containing various levels of this element were added to reagent water, surface water, drinking water and three effluents. These samples were digested by the total digestion procedure, 4.1.3 in this manual. Results for the reagent water are given below. Results for other water types and study details are found in "EPA Method Study 31, Trace Metals by Atomic Absorption (Furnace Techniques)," National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by Copeland, F.R. and Maney, J.P., January 1986.

For a concentration range of 0.51-189 μg/L.

X=1.6710(C)+1.485

S=0.6740(X)−0.342

SR=0.3895(X)−0.384

where:

C=True Value for the Concentration, μg/L

X=Mean Recovery, μg/L

S=Multi-laboratory Standard Deviation, μg/L

SR=Single-analyst Standard Deviation,         μg/L

[55 FR 33442, Aug. 15, 1990]