Laboratory Performance in the Sediment Laboratory

Quality-Assurance Project, 1996-98

U.S. Department of the Interior

U.S. Geological Survey

Water-Resources Investigations Report 99-4184

0

5

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION

PERCENT DIFFERENCE

CA_3_A0617CA_3_B5756

CA_3_C5873

HI_3_A1018HI_3_B5955

HI_3_C6074

IA_3_A4719IA_3_B6154

IA_3_C6275

KY_3_A4820KY_3_B6353

KY_3_C6476

LA_3_A4921LA_3_B6552

LA_3_C6677

MO_3_A5022MO_3_B6751

MO_3_C6878

MT_3_A5123MT_3_B6950

MT_3_C7079

NM_3_A5224NM_3_B7149

NM_3_C7280

NY_3_A5325NY_3_A5325NY_3_B7348NY_3_B7348

NY_3_C7481NY_3_C7481

OH_3_A5426OH_3_B7547

OH_3_C7682

PR_3_A5527PR_3_B7746

PR_3_C7883PR_3_D0229

PR_3_E8460 (57.6)

WA_3_A5628WA_3_B7945

WA_3_C8084

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

Kentucky

Louisiana

Missouri

Montana

New Mexico

New York (contract)

Ohio (contract)

Puerto Rico

Washington

Sample out of range Sample arrived in questionable condition
FRONT COVER: Background photograph.—Confluence of Green and Colorado Rivers in Canyonlands National Park,

Utah. Inset photographs.—Upper left, Ben Nguyen, contract employee from Metropolitan State University, preparing

samples for Sediment Laboratory Quality Assurance Study. Lower left, Control chart depicting results from interlaboratory

comparison study. Right, Single-blind sediment reference samples, ready for distribution. Photography by John Gordon,

U.S. Geological Survey.

Much appreciation is extended to the following U.S. Geological Survey employees for their contributions to this report:

Angelia M. Thacker and J. Christopher Stone of the Nevada Publication Services Unit and Joy Monson of the Colorado Publications Services Unit for final production;

Valerie Dressler of the North Dakota Publications Unit for initial typesetting;

Mary Kidd of the Colorado District for her editorial review.

Appreciation is also extended to the following U.S. Geological Survey employees for their technical review of this report:

Doug Glysson, Alan Mlodnosky, and Elizabeth Shreve
Laboratory Performance in the Sediment Laboratory

Quality-Assurance Project, 1996–98

By John D. Gordon, U.S. Geological Survey;

Carla A. Newland, Metropolitan State College of Denver; and

Shane T. Gagliardi, Colorado School of Mines

U.S. GEOLOGICAL SURVEY

Denver, Colorado

2000

Water-Resources Investigations Report 99-4184
U.S. DEPARTMENT OF THE INTERIOR

BRUCE BABBITT, Secretary

U.S. GEOLOGICAL SURVEY

CHARLES G. GROAT, Director

Any use of trade, product, or firm names in this publication is for descriptive

purposes only and does not imply endorsement by the U.S. Government

For additional information Copies of this report can be

contact: purchased from:

Chief, Branch of Quality Systems U.S. Geological Survey

U.S. Geological Survey Information Services

Box 25046, MS 414 Building 810

Denver Federal Center Box 25286, Federal Center

Denver, CO 80225-0046 Denver, CO 80225–0286

888–ASK–USGS
 iii

CONTENTS

Abstract .....................................................................................................................................................................................................1

Introduction...............................................................................................................................................................................................2

Experimental design of the Sediment Laboratory Quality-Assurance project..........................................................................................3

Sample preparation ............................................................................................................................................................................3

Interlaboratory comparisons ..............................................................................................................................................................5

Intralaboratory assessments ...............................................................................................................................................................5

Laboratory participation.....................................................................................................................................................................5

Analysis and interpretation of project data ...............................................................................................................................................8

Comparison of the 1996-98 Sediment Laboratory Quality-Assurance results with the results from pilot studies in

previous years................................................................................................................................................................................29

Control charts of the 1996-98 Sediment Laboratory Quality-Assurance results.............................................................................29

Recently implemented and proposed plans.............................................................................................................................................37

Summary .................................................................................................................................................................................................38

References ...............................................................................................................................................................................................38

FIGURES

1-15. Control charts depicting the sediment-mass percent difference for samples containing:

1. 50 to 100 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ....................40

2. 50 to 100 milligrams of fine-size material from study number 96-2, which was completed in September 1996...............41

3. 50 to 100 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .........................42

4. 50 to 100 milligrams of fine-size material from study number 97-2, which was completed in September 1997...............43

5. 50 to 100 milligrams of fine-size material from study number 98-1, which was completed in June 1998.........................44

6. 101 to 300 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ..................45

7. 101 to 300 milligrams of fine-size material from study number 96-2, which was completed in September 1996.............46

8. 101 to 300 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .......................47

9. 101 to 300 milligrams of fine-size material from study number 97-2, which was completed in September 1997.............48

10. 101 to 300 milligrams of fine-size material from study number 98-1, which was completed in June 1998.......................49

11. 2,200 to 3,200 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ............50

12. 2,200 to 3,200 milligrams of fine-size material from study number 96-2, which was completed in September 1996.......51

13. 2,200 to 3,200 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .................52

14. 2,200 to 3,200 milligrams of fine-size material from study number 97-2, which was completed in September 1997.......53

15. 2,200 to 3,200 milligrams of fine-size material from study number 98-1, which was completed in June 1998.................54

16-30. Control charts depicting the fine-size material mass percent difference for samples containing:

16. 50 to 100 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ....................55

17. 50 to 100 milligrams of fine-size material from study number 96-2, which was completed in September 1996...............56

18. 50 to 100 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .........................57

19. 50 to 100 milligrams of fine-size material from study number 97-2, which was completed in September 1997...............58

20. 50 to 100 milligrams of fine-size material from study number 98-1, which was completed in June 1998.........................59

21. 101 to 300 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ..................60

22. 101 to 300 milligrams of fine-size material from study number 96-2, which was completed in September 1996.............61

23. 101 to 300 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .......................62

24. 101 to 300 milligrams of fine-size material from study number 97-2, which was completed in September 1997.............63

25. 101 to 300 milligrams of fine-size material from study number 98-1, which was completed in June 1998.......................64

26. 2,200 to 3,200 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ............65

27. 2,200 to 3,200 milligrams of fine-size material from study number 96-2, which was completed in September 1996.......66

28. 2,200 to 3,200 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .................67

29. 2,200 to 3,200 milligrams of fine-size material from study number 97-2, which was completed in September 1997.......68

30. 2,200 to 3,200 milligrams of fine-size material from study number 98-1, which was completed in June 1998.................69
 iv

FIGURES, Continued

31-45.Control charts depicting the sand-size material mass percent difference for samples containing:

31. 50 to 100 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ....................70

32. 50 to 100 milligrams of fine-size material from study number 96-2, which was completed in September 1996...............71

33. 50 to 100 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .........................72

34. 50 to 100 milligrams of fine-size material from study number 97-2, which was completed in September 1997...............73

35. 50 to 100 milligrams of fine-size material from study number 98-1, which was completed in June 1998.........................74

36. 101 to 300 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ..................75

37. 101 to 300 milligrams of fine-size material from study number 96-2, which was completed in September 1996.............76

38. 101 to 300 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .......................77

39. 101 to 300 milligrams of fine-size material from study number 97-2, which was completed in September 1997.............78

40. 101 to 300 milligrams of fine-size material from study number 98-1, which was completed in June 1998.......................79

41. 2,200 to 3,200 milligrams of fine-size material from study number 96-1, which was completed in August 1996 ............80

42. 2,200 to 3,200 milligrams of fine-size material from study number 96-2, which was completed in September 1996.......81

43. 2,200 to 3,200 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .................82

44. 2,200 to 3,200 milligrams of fine-size material from study number 97-2, which was completed in September 1997.......83

45. 2,200 to 3,200 milligrams of fine-size material from study number 98-1, which was completed in June 1998.................84

46-57. Control charts depicting the suspended-sediment concentration percent difference for samples containing:

46. 50 to 100 milligrams of fine-size material from study number 96-2, which was completed in September 1996...............85

47. 50 to 100 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .........................86

48. 50 to 100 milligrams of fine-size material from study number 97-2, which was completed in September 1997...............87

49. 50 to 100 milligrams of fine-size material from study number 98-1, which was completed in June 1998.........................88

50. 101 to 300 milligrams of fine-size material from study number 96-2, which was completed in September 1996.............89

51. 101 to 300 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .......................90

52. 101 to 300 milligrams of fine-size material from study number 97-2, which was completed in September 1997.............91

53. 101 to 300 milligrams of fine-size material from study number 98-1, which was completed in June 1998.......................92

54. 2,200 to 3,200 milligrams of fine-size material from study number 96-2, which was completed in September 1996.......93

55. 2,200 to 3,200 milligrams of fine-size material from study number 97-1, which was completed in July 1997 .................94

56. 2,200 to 3,200 milligrams of fine-size material from study number 97-2, which was completed in September 1997.......95

57. 2,200 to 3,200 milligrams of fine-size material from study number 98-1, which was completed in June 1998.................96

58. Sample leakage by laboratory, August 1996 through June 1998 ...............................................................................................97

59-70. Control charts depicting the suspended-sediment concentration percent difference for study numbers 96-2

through 98-1 for samples containing 50 to 100 milligrams of sediment for the:

59. Salinas, California, laboratory.............................................................................................................................................98

60. Honolulu, Hawaii, laboratory ..............................................................................................................................................99

61. Iowa City, Iowa, laboratory ...............................................................................................................................................100

62. Louisville, Kentucky, laboratory .......................................................................................................................................101

63. Baton Rouge, Louisiana, laboratory..................................................................................................................................102

64. Rolla, Missouri, laboratory................................................................................................................................................103

65. Helena, Montana, laboratory .............................................................................................................................................104

66. Albuquerque, New Mexico, laboratory .............................................................................................................................105

67. Ithaca, New York, (contract) laboratory ............................................................................................................................106

68. Columbus, Ohio, (contract) laboratory..............................................................................................................................107

69. Guaynabo, Puerto Rico, laboratory ...................................................................................................................................108

70. Vancouver, Washington, laboratory...................................................................................................................................109
 v

FIGURES, Continued

71-82. Control charts depicting the suspended-sediment concentration percent difference for study numbers 96-2

through 98-1 for samples containing 101 to 300 milligrams of sediment for the:

71. Salinas, California, laboratory ...........................................................................................................................................110

72. Honolulu, Hawaii, laboratory.............................................................................................................................................111

73. Iowa City, Iowa, laboratory................................................................................................................................................112

74. Louisville, Kentucky, laboratory........................................................................................................................................113

75. Baton Rouge, Louisiana, laboratory ..................................................................................................................................114

76. Rolla, Missouri, laboratory ................................................................................................................................................115

77. Helena, Montana, laboratory..............................................................................................................................................116

78. Albuquerque, New Mexico, laboratory..............................................................................................................................117

79. Ithaca, New York, (contract) laboratory.............................................................................................................................118

80. Columbus, Ohio, (contract) laboratory ..............................................................................................................................119

81. Guaynabo, Puerto Rico, laboratory....................................................................................................................................120

82. Vancouver, Washington, laboratory ...................................................................................................................................121

83-94. Control charts depicting the suspended-sediment concentration percent difference for study numbers 96-2

through 98-1 for samples containing 2,200 to 3,200 milligrams of sediment for the:

83. Salinas, California, laboratory ...........................................................................................................................................122

84. Honolulu, Hawaii, laboratory.............................................................................................................................................123

85. Iowa City, Iowa, laboratory................................................................................................................................................124

86. Louisville, Kentucky, laboratory........................................................................................................................................125

87. Baton Rouge, Louisiana, laboratory ..................................................................................................................................126

88. Rolla, Missouri, laboratory ................................................................................................................................................127

89. Helena, Montana, laboratory..............................................................................................................................................128

90. Albuquerque, New Mexico, laboratory..............................................................................................................................129

91. Ithaca, New York, (contract) laboratory.............................................................................................................................130

92. Columbus, Ohio, (contract) laboratory ..............................................................................................................................131

93. Guaynabo, Puerto Rico, laboratory....................................................................................................................................132

94. Vancouver, Washington, laboratory ...................................................................................................................................133

95. Graphs summarizing the distribution of reported values for each laboratory that participated in the Sediment

Laboratory Quality-Assurance project from August 1996 to June 1998..................................................................................134

TABLES

1. Sample fine-size material mass and percent sand-size material in each Sediment Laboratory

Quality-Assurance study...............................................................................................................................................................4

2-6. Summary of laboratory participation in the Sediment Laboratory Quality-Assurance project:

2. Study-number 96-1 ................................................................................................................................................................5

3. Study-number 96-2 ................................................................................................................................................................6

4. Study-number 97-1 ................................................................................................................................................................6

5. Study-number 97-2 ................................................................................................................................................................7

6. Study-number 98-1 ................................................................................................................................................................7

7-10. Median percent difference for:

7. Suspended-sediment concentration........................................................................................................................................9

8. Sediment mass .......................................................................................................................................................................9

9. Sand-size material mass.......................................................................................................................................................10

10. Fine-size material mass........................................................................................................................................................11

11-15. Statistical results summary for the Sediment Laboratory Quality-Assurance project:

11. Study number 96-1...............................................................................................................................................................12

12. Study number 96-2...............................................................................................................................................................13

13. Study number 97-1...............................................................................................................................................................14

14. Study number 97-2...............................................................................................................................................................15

15. Study number 98-1...............................................................................................................................................................16
 vi

16-27. Summary results for Sediment Laboratory Quality-Assurance studies in the:

16. Salinas, California, laboratory .............................................................................................................................................17

17. Honolulu, Hawaii, laboratory ..............................................................................................................................................18

18. Iowa City, Iowa, laboratory..................................................................................................................................................19

19. Louisville, Kentucky, laboratory..........................................................................................................................................20

20. Baton Rouge, Louisiana, laboratory ....................................................................................................................................21

21. Rolla, Missouri, laboratory ..................................................................................................................................................22

22. Helena, Montana, laboratory ...............................................................................................................................................23

23. Albuquerque, New Mexico, laboratory ...............................................................................................................................24

24. Ithaca, New York, (contract) laboratory ..............................................................................................................................25

25. Columbus, Ohio, (contract) laboratory................................................................................................................................26

26. Guaynabo, Puerto Rico, laboratory .....................................................................................................................................27

27. Vancouver, Washington, laboratory .....................................................................................................................................28

28. 1992 pilot study sediment mass percent difference....................................................................................................................30

29. 1994 pilot study sediment mass percent difference....................................................................................................................30

30-34. Control limit exceedances (+3 F-pseudosigma) for the Sediment Laboratory Quality-Assurance project:

30. Study number 96-1 ..............................................................................................................................................................32

31. Study number 96-2 ..............................................................................................................................................................33

32. Study number 97-1 ..............................................................................................................................................................34

33. Study number 97-2 ..............................................................................................................................................................35

34. Study number 98-1 ..............................................................................................................................................................36

CONVERSION FACTORS

Temperature can be converted from degree Celsius (°C) to degree Fahrenheit (°F) by using the following equation:

°F = 9/5 (°C) + 32

The following terms and abbreviations also are used in this report:

grams (g)

micrometer (μm)

milligram (mg)

milligrams per liter (mg/L)

milliliter (mL)

maximum probability of rejecting the null hypothesis when it is true (α)

Multiply By To obtain

centimeter (cm) 0.3937 inch

liter (L) 1.057 quart

milliliter (mL) 0.03381 ounce, fluid
Abstract 1

Abstract

This report describes the results of the first

3 years of an ongoing study of sediment laboratories used by the U.S. Geological Survey (USGS).

The sediment laboratories currently in operation

constitute the entire USGS national laboratory

system for sediment analyses. As with all environmental data, physical sediment data can be

expected to contain a certain amount of difference,

whether the difference resulted from the collecting, transporting, or analyzing of the sample.

Because it is important to know how each laboratory is performing, the USGS initiated the Sediment Laboratory Quality-Assurance (SLQA)

project in August 1996. From August 1996

through June 1998, five studies were made, the

results of which are the basis of this report.

The focus of the project is on quantitative

analyses done on water-sediment mixtures to

derive suspended-sediment concentrations, sediment-mass determinations, and sand/fine separations. For the purpose of this report, all mass

determinations are net values—the tare weight of

the container is excluded. The fine-size material is

defined as particles sieved to a size of less than 62

micrometers (μm) and sand-size material is

defined as particles sieved to a size of between 63

and 125 μm. Also, in this report, class 1 samples

are defined as samples containing 50 to 100 milligrams (mg) of fine-size material, class 2 samples

are defined as samples containing 101 to 300 mg

of fine-size material, and class 3 samples are

defined as samples containing 2,200 to 3,200 mg

of fine-size material. In studies 96-1 through 98-1,

the amount of sand added to each sample ranged

from 9 to 28 percent of the mass of fine-size material in each sample class.

 Analytical results from all sediment quality-control samples are compiled and statistically

summarized by the USGS, Branch of Quality Systems, both on an intra- and interlaboratory basis.

When evaluating these data, the reader needs to

keep in mind that every measurement has an error

component associated with it. It is premature to

use the data from the first five SLQA studies to

judge any of the laboratories as performing in an

unacceptable manner. There were, however, some

notable differences in the results for the 12 laboratories that participated in the five SLQA studies.

For example, the overall median percent difference for suspended-sediment concentration on an

individual laboratory basis ranged from –18.04 to

–0.33 percent. Five of the 12 laboratories had an

overall median percent difference for suspended-sediment concentration of –2.02 to

–0.33 percent. There was less variability in the

median difference for the measured fine-size

material mass. The overall median percent difference for fine-size material mass ranged from

–10.11 to –4.27 percent. Except for one laboratory,

the median difference for fine-size material mass

was within a fairly narrow range of –6.76 to –4.27

percent. The median percent difference for

sand-size material mass differed among laboratories more than any other physical sediment property measured in the study. The overall median

percent difference for the sand-size material mass

ranged from –1.49 percent to 26.39 percent. Five

of the nine laboratories that do sand/fine separaLaboratory Performance in the Sediment Laboratory

Quality-Assurance Project, 1996-98

By John D. Gordon, Carla A. Newland, and Shane T. Gagliardi
2 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

tions had overall median percent differences that

ranged from –1.49 to 2.98 percent for sand-size

material mass. Careful review of the data reveals

that certain laboratories consistently produced

data within statistical control limits for some or all

of the physical sediment properties measured in

this study, whereas other laboratories occasionally

produced data that exceeded the control limits.

INTRODUCTION

The collection and analysis of fluvial sediment

samples has been an integral part of hydrologic studies

in the United States for over 100 years (Glysson,

1989). Sediment is one of many major pollutants in

waterways of the United States and represents a concern to all aspects of the aquatic ecosystem. Understanding the importance of sediment processes in a

wide range of hydrologic investigations has increased

markedly in the past two decades. For example, sediment processes are critical factors in the fate and transport of toxic substances (Choi and Chen, 1976) and

even low-threshold concentrations of contaminated

sediment can adversely affect an ecosystem (Fairchild,

1987). As the sediment load is transported in a river,

sediment processes controlling bedload transport and

resuspension acutely influence the distribution and

transformation of toxic materials. Sediment data also

are important in computing the probable specific mass

of sediment deposited in a reservoir or channel and in

calculating the reservoir storage capacity or dredging

requirements to keep a waterway open for navigation

(Guy, 1969). The need for accurate and precise sediment analyses has increased concurrently with a

greatly increased demand for sediment sample analyses. The approved methods for fluvial sediment data

collection (Edwards and Glysson, 1986) and sediment

analysis methods (Guy, 1969) are described in the U.S.

Geological Survey Techniques for Water-Resources

Investigations report series. Detailed quality-assurance

guidelines are also available (Knott and others, 1992;

Matthes and others, 1991). However, prior to the start

of the Sediment Laboratory Quality-Assurance

(SLQA) project in 1996, scant information was available on the bias and precision of sediment data produced by or for the U.S. Geological Survey (USGS).

What limited information was available was not published in a citable report and was derived from a few

sporadic interlaboratory comparisons—there was no

ongoing assessment of laboratory bias and precision.

Such a program is vital if the USGS is to achieve its

goal of developing a nationally consistent and comparable database of physical sediment properties of

known quality.

About 63,000 suspended-sediment concentration

analyses and 16,000 sand/fine separations were performed either by or for the USGS in 1994 (Schroder

and others, 1996). In 1991, the USGS Office of Surface Water (OSW) issued Technical Memorandum

OSW 91.11 (U.S. Geological Survey Office of Surface

Water Technical Memorandum No. 91.11, 1991) that

contained a list of quality-assurance requirements for

sediment laboratories that analyze samples for the

USGS. One of the requirements listed in this memorandum is “successful participation in a standard reference-sample project for sediment analysis.” At the

time this memorandum was issued, a standard reference-sample project for the determination of physical

sediment properties did not exist. Working with the

USGS Sediment Action Committee and the USGS

Water Quality Service Unit in Ocala, Florida, the

Branch of Quality Systems (BQS) distributed test

samples as part of a pilot standard reference study in

1992 and 1994. All USGS laboratories that analyze

sediment samples and one contract laboratory participated. Results of the pilot studies indicated that a standard reference-sample project was feasible and

practical.

Following the 1992 and 1994 pilot studies, the

BQS continued to pursue the development and testing

of a standard reference-sample project for measurement of physical sediment properties. In 1996, these

efforts led to an external quality-assurance project for

the sediment determinations done by and for the

USGS. The OSW Technical Memorandum 96.11 officially announced the formation of a quality-assurance

project for sediment analyses, and the SLQA project

began operation in August 1996 (U. S. Geological

Survey Office of Surface Water Technical Memorandum No. 96.11, 1996).

The primary objectives of this project are to identify and eliminate systematic bias and to quantify the

precision of sediment analyses. It is important to evaluate sediment analysis on an ongoing basis to monitor

intra- and interlaboratory precision and to detect laboratory-specific bias in a timely manner. The quality

of sediment analyses does not remain static over

time given inevitable method changes and turnover in

laboratory personnel. Sediment-analysis results from
EXPERIMENTAL DESIGN OF THE SEDIMENT LABORATORY QUALITY-ASSURANCE PROJECT 3

an entire region can be biased if the laboratory servicing that region produces biased data. Laboratory bias

can also be a major concern when national data assessments are completed because the comparability of

results for different regions can be diminished.

This report describes the results of the first 3 years

of an ongoing study of sediment laboratories used by

the USGS. The USGS relies on these laboratories for

all of their physical sediment data; therefore, it is

important to know how each laboratory is performing.

As with all environmental data, physical sediment data

can be expected to contain a certain amount of error,

whether the error resulted from the collecting, transporting, or analyzing of the sample. Suspended-sediment concentration data, the total sediment mass in

each sample, and the results of sand/fine separations

were all analyzed. For the purpose of this report, all

mass determinations were net values—the tare weight

of the container was excluded.

From August 1996 through June 1998, five studies were completed, the results of which are the basis

of this report. The results of the individual laboratories, as well as overall summary statistics for the laboratories as a group are presented. This information will

aid the reader in evaluating the overall bias and precision of physical sediment data produced by or for the

USGS between 1996 and 1998 as well as gaining

information on individual laboratory results during

this time period.

EXPERIMENTAL DESIGN OF THE

SEDIMENT LABORATORY

QUALITY-ASSURANCE PROJECT

Sample Preparation

Samples were prepared gravimetrically by using

two materials: AC spark-plug dust and South Dakota

sand. The AC spark-plug dust is manufactured by

General Motors Spark Plug Division and is a

fine-grade material representative of the fine-particle

fraction of sediment samples (Johnston and Swanson,

1981). The sand used in this project was obtained by

sieving sediment to a size between 63 and 125

micrometers (μm) and drying at 105°C for a minimum

of 24 hours. The AC spark-plug dust that was used

as the fine-size material was sieved to a size less than

62 μm and also was dried at 105°C for a minimum of

24 hours.

Three amounts were chosen for each set of test

samples sent to participating laboratories in a given

study. These samples are identified as class 1, 2, or 3

samples. Class 1 samples are defined as samples containing 50 to 100 milligrams (mg) of fine-size material; class 2 samples are defined as samples containing

101 to 300 mg of fine-size material; and class 3 samples are defined as samples containing 2,200 to 3,200

mg of fine-size material. The target mass of fine-size

material is referred to as the “base mass” of each sample. In studies 96-1 through 98-1, sand was added in

amounts ranging from 9 to 28 percent of the base mass

of fine-size material in each sample class (table 1).

In the first study (96-1), the three amounts of

fine-size material were 50 mg, 200 mg, and 2,200 to

2,700 mg. In the second study (96-2), the library of

50-mg samples was depleted, and the decision was

made to use 100-mg samples of fine size material for

sample class 1. For class 2 samples in the second study

(96-2), 300 mg of fine-size material was used, and for

class 3 samples, 2,200 to 2,700 mg of fine-size material was used. In studies 97-1, 97-2, and 98-1, the three

amounts of fine-size material were 58 mg, 116 mg,

and 2,300 to 2,700 mg. Studies 96-1 and 96-2 were

completed in August and September 1996, respectively. Studies 97-1 and 97-2 were completed in July

and September 1997, respectively, and study 98-1 was

completed in June 1998 (table 1).

Each test sample was custom made at the BQS.

The sample volume varied slightly in mass, and the

mass was known with an accuracy to within 0.10 mg.

The sand-size material was tested for resistance to

dissolution. Three samples of sand-size material were

sieved, dried, and weighed. A total of 50 milliliters

(mL) of deionized water was then added to the samples. After 48 hours, the samples were dried at 105°C

until all of the water evaporated. The recovery of the

sand-size material ranged from 99.6 to 100.3 percent,

indicating that the sand-size material did not dissolve.

The recovery of sand-size material that measured

greater than 100 percent was attributed to a slight error

in measurement.

Nine samples, three from each sample class, were

sent to the laboratories in each SLQA study. Regardless of whether the participating laboratories were

internal USGS laboratories or external contract laboratories, all the laboratories shown in the figures 1

through 57 (at the back of the report) analyzed sediment samples for the USGS. The laboratories were

asked to determine the sediment mass and the sus-
4 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

pended-sediment concentration in milligrams per liter

and to perform the sand/fine separations. Throughout

this report the term “sediment mass” refers to the net

sediment weight of the sample as defined by Guy,

1969. The sand/fine separation results reported by the

laboratories were used to calculate the reported

sand-size and fine-size material mass in each sample.

As of August 31, 1998, five SLQA studies had

been completed. In study number 96-1, the samples

were sent to the laboratories as dry mixtures of

sand-size and fine-size material, which the laboratories reconstituted to resemble a normal suspended-sediment sample by adding water. Although the

laboratories were asked to keep accurate records of the

volume of water added to the samples, only 6 of 11

laboratories complied with this request. Consequently,

suspended-sediment concentration data for study number 96-1 are not included in this report. For study number 96-2, and all subsequent studies, the samples were

shipped as sand/fine mixtures in deionized water using

the same type of sand-size and fine-size material used

in study number 96-1. The preparation of water-based

samples eliminated some of the handling steps

required by the laboratories for the first set of samples

and created the opportunity to evaluate the effects of

some commonly used shipping procedures on sediment determinations. The samples were prepared in

glass quart-size and pint-size bottles with snap-on and

threaded lids, respectively.

Beginning with study number 96-2, the suspended-sediment samples were shipped to the laboratories in specially designed plastic crates obtained

from the Federal Interagency Sedimentation project.

The bottles and crates used in the study and the manner in which samples were packaged were designed to

replicate sediment-sample shipping procedures commonly used throughout the USGS.

Table 1. Sample fine-size material mass and percent sand-size material in each Sediment Laboratory

Quality-Assurance study

Study

number

Sample

class

Range of fine-sized

material mass in

each sample class

(milligrams)

Target mass of

fine-size material

(milligrams)

Percentage of sand-size

material added to the

mass of fine-size material

96-1 1 50 to 100 50.0 10, 15, 20

2 101 to 300 200.0 10, 15, 20

3 2,200 to 3,200 2,200.0

2,700.0

15, 20

10, 15

96-2 1 50 to 100 100.0 10, 15, 20

2 101 to 300 300.0 10, 15, 20

3 2,200 to 3,200 2,200.0

2,700.0

10

15, 20

97-1 1 50 to 100 58.0 11, 18, 28

2 101 to 300 116.0 9, 15, 23

3 2,200 to 3,200 2,300.0

2,700.0

17, 24

12

97-2 1 50 to 100 58.0 11, 18, 28

2 101 to 300 116.0 9, 15, 23

3 2,200 to 3,200 2,300.0

2,700.0

17, 24

12

98-1 1 50 to 100 58.0 12, 18, 28

2 101 to 300 116.0 9, 15, 23

3 2,200 to 3,200 2,300.0

2,700.0

17, 24

12, 20
EXPERIMENTAL DESIGN OF THE SEDIMENT LABORATORY QUALITY-ASSURANCE PROJECT 5

Interlaboratory Comparisons

The interlaboratory comparison SLQA project

was implemented in 1996 to determine if differences

existed among the results of participating laboratories

and to estimate any changes in overall laboratory precision. For each SLQA study, complete instructions

were distributed to the laboratories. The instructions

specified that the laboratories furnish the BQS with

detailed suspended-sediment concentration and

sand/fine separation-analysis data, including all of the

requested ancillary data.

During 1996-98, the main focus of the study was

to evaluate sand/fine separations and suspended-sediment concentration data. Reports that describe the performance of each laboratory were distributed at the

completion of each study. Each laboratory was asked

to carefully review their reported results and immediately report any discrepancies. The SLQA project staff

verified all of the data used in this report.

Intralaboratory Assessments

In addition to interlaboratory comparisons, the

results from each laboratory were assessed individually to determine intralaboratory precision and bias.

Each participating laboratory was furnished updated

estimates of their internal precision and bias, based on

analysis of the full suite of reference samples that were

shipped to the laboratory after each study by SLQA

project personnel.

Laboratory Participation

All of the USGS laboratories that analyze physical sediment data, as well as all contract laboratories

that analyze physical sediment data for the USGS, participated in the SLQA study. Tables 2 through 6 show

the studies each of the laboratories participated in, and

the type of data they analyzed.

1

Suspended-sediment concentration data were not analyzed for this study.

2

Some laboratories did not determine sand/fine separations for their customers and, thus, did not complete these analyses

for the interlaboratory comparison study. 3

Not all samples were analyzed for all constituents.

4

Contract laboratory.

Table 2. Summary of laboratory participation in the Sediment Laboratory Quality-Assurance project, study

number 96-1

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample

class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount ranging from 9 to 28

percent of the mass of fine-size material in each sample class]

Sand/fine determinations Sediment-mass determinations Suspended-sediment concentration1

Participating

laboratory

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

California x x x x x x

Hawaii2,3 xxx

Iowa x x x x x x

Kentucky x x x x x x

Louisiana x x x x x x

Missouri x x x x x x

Montana x x x x x x

New Mexico x x x x x x

Ohio2,4 xxx

Puerto Rico x x x x x x

Washington x x x x x x
6 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1

Some laboratories did not determine sand/fine separations for their customers and, thus, did not complete these analyses

for the interlaboratory comparison study. 2

Not all samples were analyzed for all constituents.

3

Contract laboratory.

Table 3. Summary of laboratory participation in the Sediment Laboratory Quality-Assurance project, study

number 96-2

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample

class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount ranging from 9 to 28

percent of the mass of fine-size material in each sample class]

Sand/fine determinations Sediment-mass determinations Suspended-sediment concentration

Participating

laboratory

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

California x x x x x x x x x

Hawaii1,2 xx x x x

Iowa2 x xx x x x

Kentucky2 xxx x x x x x x

Louisiana x x x x x x x x x

Missouri2 xxx x x x x x x

Montana2 xxx x x x x x x

New Mexico x x x x x x x x x

Ohio1,3 x xx x x x

Puerto Rico x x x x x x x x x

Washington1 x xx x x x

1

Some laboratories did not determine sand/fine separations for their customers and, thus, did not complete these analyses for

the interlaboratory comparison study. 2

Not all samples were analyzed for all constituents.

3

Contract laboratory.

Table 4. Summary of laboratory participation in the Sediment Laboratory Quality-Assurance project, study

number 97-1

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample

class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount ranging from 9 to 28 percent

of the mass of fine-size material in each sample class]

Sand/fine determinations Sediment-mass determinations Suspended-sediment concentration

Participating

laboratory

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

California x x x x x x x x x

Hawaii1 xxx x x x

Iowa x x x x x x x x x

Kentucky x x x x x x x x x

Louisiana x x x x x x x x x

Missouri2 xxx x x x x x x

Montana2 xxx x x x x x x

New Mexico x x x x x x x x x

New York1,2,3 xxx

Ohio1,3 xxx x x x

Puerto Rico x x x x x x x x x

Washington x x x x x x x x x
EXPERIMENTAL DESIGN OF THE SEDIMENT LABORATORY QUALITY-ASSURANCE PROJECT 7

1Some laboratories did not determine sand/fine separations for their customers and, thus, did not complete these analyses

for the interlaboratory comparison study. 2Not all samples were analyzed for all constituents.

3Contract laboratory.

Table 5. Summary of laboratory participation in the Sediment Laboratory Quality-Assurance project, study

number 97-2

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample

class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount ranging from 9 to 28

percent of the mass of fine-size material in each sample class]

Sand/fine determinations Sediment-mass determinations Suspended-sediment concentration

Participating

laboratory

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

California x x x x x x x x x

Hawaii1 xx x x x x

Iowa x x x x x x x x x

Kentucky x x x x x x x x x

Louisiana x x x x x x x x x

Missouri x x x x x x x x x

Montana x x x x x x x x x

New Mexico2 xxx x x x x x x

New York1,3 xxx

Ohio1,3 xx x x x x

Puerto Rico2 xxx x x x x x x

Washington x x x x x x x x x

1

Some laboratories did not determine sand/fine separations for their customers and, thus, did not complete these analyses

for the interlaboratory comparison study. 2

Not all samples were analyzed for all constituents.

3

Contract laboratory.

Table 6. Summary of laboratory participation in the Sediment Laboratory Quality-Assurance project, study

number 98-1

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material;

sample class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount ranging from 9 to

28 percent of the mass of fine-size material in each sample class]

Sand/fine determinations Sediment-mass determinations Suspended-sediment concentration

Participating

laboratory

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

Sample

class

1

Sample

class

2

Sample

class

3

California x x x x x x x x x

Hawaii1 xx x x x x

Iowa x x x x x x x x x

Kentucky x x x x x x x x x

Louisiana x x x x x x x x x

Missouri x x x x x x x x x

Montana x x x x x x x x x

New Mexico x x x x x x x x x

New York1,3 xxx

Ohio1,3 xx x x x x

Puerto Rico1 xx x x x x

Washington x x x x x x x x x
8 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

ANALYSIS AND INTERPRETATION OF

PROJECT DATA

The percent differences for the reported sediment

mass, sand-size material mass, and fine-size material

mass are calculated as:

,

where:

PD is the percent difference;

RM is the reported mass, in milligrams; and

KM is the known mass determined gravimetrically by BQS, in milligrams.

All mass determinations are net values—the tare

weight of the container is excluded.

The percent difference for suspended-sediment

concentration is calculated by using a similar formula:

,

where:

PD is the percent difference;

RC is the reported concentration, in milligrams per liter;

KC is the theoretical concentration, based on

the known (actual) sediment mass determined gravimetrically by BQS, in milligrams, and the known volume of water

used to prepare the sample, measured in

liters.

The known sediment mass included the fine-size and

sand-size material mass in each sample.

The overall median percent differences for each

of the five separate studies completed by June 1998

are contained in tables 7 through 10. Sequential year

and study numbers identify the individual studies.

The median suspended-sediment concentration

percent differences were somewhat larger in the most

recent studies than in the earlier studies. For example,

in study number 96-2 (suspended-sediment concentration percent differences were not calculated for study

number 96-1), the median suspended-sediment concentration percent difference for class 1 samples was

–2.45, the median percent difference for class 2 samples was –1.57, and the median suspended-sediment

concentration percent difference for class 3 samples

was –0.60. In study number 98-1, the median percent

difference for class 1 samples was –4.86, the median

percent difference for class 2 samples was –5.48, and

the median percent difference for class 3 samples was

–1.27 (table 7).

The magnitude of the median percent difference

for sediment mass changed slightly over the course of

the five studies: In study number 96-1, the median percent difference for sediment mass was –4.92 for class

1 samples, –4.29 percent for class 2 samples, and

–1.92 percent for class 3 samples. In study number

98-1, the median percent difference for sediment mass

was –5.15 percent for class 1 samples, –4.82 percent

for class 2 samples, and –1.70 percent for class 3 samples (table 8).

For the small and midsize samples (classes 1 and

2), the median percent differences for sand/fine separations were larger than the differences associated with

sediment mass determinations. The results in tables 9

through 10 indicate that the median percent differences for sand/fine separations were consistently positive for sand-size material and remained negative for

fine-size material. The median percent differences for

the mass of sand-size material tended to improve substantially over time. For example, in study number

96-1, the median percent difference for class 1 samples was 23.21, the median percent difference for class

2 samples was 16.14, and the median percent difference for class 3 samples was 16.48. In study number

98-1 the median percent difference for class 1 samples

was 7.08, the median percent difference was 3.48 for

class 2 samples, and 0.38 percent for class 3 samples

(table 9).

Median percent differences for the mass of

fine-size material changed slightly over time. In study

number 96-1, the median percent difference for the

mass of fine-size material was –7.96 for class 1 samples, the median percent difference for class 2 samples

was –6.88, and the median percent difference for class

3 samples was –4.46. In study number 98-1, the

median percent difference for the mass of fine-size

material was –7.81 percent for class 1 samples, –7.21

percent for class 2 samples, and –2.11 percent for class

3 samples (table 10).

PD = RM - KM

KM ----------------------- X 100

PD = RC - KC

KC -------------------- X 100
ANALYSIS AND INTERPRETATION OF PROJECT DATA 9

Table 7. Median percent difference for suspended-sediment concentration

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size

material; sample class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount

ranging from 9 to 28 percent of the mass of fine-size material in each sample class; N/A, not applicable]

Study

number

Number of

laboratories

Sample

class

Sample base mass

(milligrams)

Median percent

 difference

96-1 11 1 N/A N/A

96-2 11 1 100.0 -2.45

97-1 12 1 58.0 -3.60

97-2 12 1 58.0 -2.91

98-1 12 1 58.0 -4.86

96-1 12 2 N/A N/A

96-2 12 2 300.0 -1.57

97-1 12 2 116.0 -3.38

97-2 12 2 116.0 -3.77

98-1 12 2 116.0 -5.48

96-1 12 3 N/A N/A

96-2 12 3 2,200.0 -0.60

2,700.0

97-1 12 3 2,300.0 -0.36

2,700.0

97-2 12 3 2,300.0 -0.72

2,700.0

98-1 12 3 2,300.0 -1.27

2,700.0

Table 8. Median percent difference for sediment mass

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size

material; sample class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount

ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Study

 number

Number of

 laboratories

Sample

class

Sample base mass

(milligrams)

Median

percent

difference

96-1 11 1 50.0 -4.92

96-2 11 1 100.0 -5.05

97-1 12 1 58.0 -3.82

97-2 12 1 58.0 -4.54

98-1 12 1 58.0 -5.15

96-1 12 2 200.0 -4.29

96-2 12 2 300.0 -4.85

97-1 12 2 116.0 -4.92

97-2 12 2 116.0 -4.77

98-1 12 2 116.0 -4.82

96-1 12 3 2,200.0 -1.92

2,700.0

96-2 12 3 2,200.0 -1.87

2,700.0

97-1 12 3 2,300.0 -1.36

2,700.0

97-2 12 3 2,300.0 -1.38

2,700.0

98-1 12 3 2,300.0 -1.70

2,700.0
10 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

Complete statistical summaries for each of the

five SLQA studies completed between 1996 through

1998 are listed in tables 11 through 15. These tables

provide information about the central tendency and

variability of the data for each study. For example, the

overall summary statistics for the first interlaboratory

comparison study, study number 96-1, are given in

table 11. The overall summary statistics for the most

recent interlaboratory comparison study, study number

98-1, are given in table 15.

While the mean and the median are useful for

defining the central tendency of the data, the standard

error, 25th percentile, 75th percentile, F-pseudosigma,

standard deviation, range, and the minimum and maximum are indicators of the amount of variability in the

data. To calculate the F-pseudosigma, the lower quartile was subtracted from the upper quartile, and then

divided by 1.349. The upper quartile is approximately

equal to the 75th percentile in the data distribution,

while the lower quartile is approximately equal to the

25th percentile in the data distribution. The smaller the

F-pseudosigma, the more precise the determination

was considered to be.

F-pseudosigma upper quartile - lower quartile

1.349 = -----------------------------------------------------------------------

Table 9. Median percent difference for sand-size material mass

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material;

sample class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount ranging from

9 to 28 percent of the mass of fine-size material in each sample class]

Study

 number

Number of

 laboratories

Sample

 class

Sample base mass

(milligrams)

Median

 percent

difference

96-1 11 1 50.0 23.21

96-2 11 1 100.0 16.70

97-1 12 1 58.0 8.28

97-2 12 1 58.0 1.82

98-1 12 1 58.0 7.08

96-1 12 2 200.0 16.14

96-2 12 2 300.0 14.69

97-1 12 2 116.0 4.54

97-2 12 2 116.0 1.46

98-1 12 2 116.0 3.48

96-1 12 3 2,200.0

2,700.0

16.48

96-2 12 3 2,200.0

2,700.0

17.70

97-1 12 3 2,300.0 2.25

2,700.0

97-2 12 3 2,300.0 0.72

2,700.0

98-1 12 3 2,300.0 0.38

2,700.0
ANALYSIS AND INTERPRETATION OF PROJECT DATA 11

Tables 11-15 show that there was more variability

for sand-size material mass percent difference than for

any of the other measurements. For example, for study

number 96-1, the F-pseudosigma calculated from

sand-size material mass percent differences using class

1 samples was 17.29; for class 2 samples the F-pseudosigma was 10.45, and for class 3 samples the

F-pseudosigma was 11.46. For study number 98-1, the

F-pseudosigma calculated from sand-size material

mass percent difference using class 1 sample was 8.81;

for class 2 samples the F-pseudosigma was 7.47, and

for class 3 samples the F-pseudosigma was 2.31.

The results for each laboratory participating in the

SLQA project between August 1996 and June 1998

are provided in tables 16 through 27. These tables give

details on a sample-by-sample basis, including the percent difference for each study for the reported suspended-sediment concentration, sediment mass,

fine-size material mass, and sand-size material mass.

These tables are a descriptive means to provide a comparison between different laboratories that produce

physical sediment data for the USGS.

The summary statistics at the bottom of tables

16-27 are an indication of overall laboratory performance over the course of the study. Laboratories with

median percent difference values closer to zero may be

producing data with less bias. The 25th percentile, 75th

percentile, F-pseudosigma, and the interquartile range

values are useful for assessing the magnitude of variability in each laboratory’s results.

Table 10. Median percent difference for fine-size material mass

[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material;

sample class 3, 2,200 to 3,200 milligrams of fine-size material; sand-size material was added in an amount ranging

from 9 to 28 percent of the mass of fine-size material in each sample class]

Study

 number

Number of

 laboratories

Sample

class

Sample base mass

(milligrams)

Median

 percent

difference

96-1 11 1 50.0 -7.96

96-2 11 1 100.0 -9.09

97-1 12 1 58.0 -5.93

97-2 12 1 58.0 -6.60

98-1 12 1 58.0 -7.81

96-1 12 2 200.0 -6.88

96-2 12 2 300.0 -9.24

97-1 12 2 116.0 -6.33

97-2 12 2 116.0 -6.73

98-1 12 2 116.0 -7.21

96-1 12 3 2,200.0 -4.46

2,700.0

96-2 12 3 2,200.0 -5.66

2,700.0

97-1 12 3 2,300.0 -1.67

2,700.0

97-2 12 3 2,300.0 -2.00

2,700.0

98-1 12 3 2,300.0 -2.11

2,700.0
12 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1The confidence level for specific statistics returns the confidence interval for a population mean. The confidence interval is a range on either side of a sampl

probability of rejecting the null hypothesis when it is true. If we assume alpha equals 0.05 we need to calculate the area under the standard normal curve that equals value is +1.96. The confidence interval is the sample mean +1.96 times the standard deviation divided by the square root of the number of data points.

Table 11. Statistical results summary for the Sediment Laboratory Quality-Assurance project, study number 96-1[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,200 milligrams omaterial was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class; N/A, not applicable]

Sample class 1 Sample class 2 Sa

Statistic

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-si

materi

mass

percen

differen

Mean -4.13 -7.92 27.94 N/A -4.25 -7.07 19.09 N/A -3.56 -4.24 Standard error 1.30 1.23 9.22 N/A 0.52 0.69 2.32 N/A 1.39 0.77 Median -4.92 -7.96 23.21 N/A -4.29 -6.88 16.14 N/A -1.92 -4.46 25th percentile -6.59 -10.05 11.88 N/A -5.76 -9.11 11.71 N/A -3.31 -6.04 75th percentile -0.88 -6.58 35.21 N/A -1.86 -4.47 25.81 N/A -0.58 -2.43 F-pseudosigma 4.24 2.57 17.29 N/A 2.89 3.44 10.45 N/A 2.03 2.67 Standard deviation 7.11 6.39 47.92 N/A 2.92 3.60 12.03 N/A 7.85 4.0Sample variance 50.62 40.80 2296.13 N/A 8.55 12.95 144.75 N/A 61.70 16.09 Kurtosis 4.02 7.29 16.93 N/A 0.60 0.31 2.17 N/A 27.18 3.1Skewness 1.06 1.13 3.62 N/A -0.72 -0.55 0.89 N/A -5.05 0.85 Range 37.69 39.85 284.67 N/A 11.64 15.25 61.16 N/A 45.41 19.98 Minimum -17.89 -24.90 -40.69 N/A -11.77 -15.97 -5.68 N/A -45.05 -11.6Maximum 19.80 14.95 243.98 N/A -0.13 -0.72 55.48 N/A 0.36 8.37 Count 30.00 27.00 27.00 N/A 32.00 27.00 27.00 N/A 32.00 27.00 Confidence level

(95.0 percent)1

2.66 2.53 18.96 N/A 1.05 1.42 4.76 N/A 2.83 1.59 
ANALYSIS AND INTERPRETATION OF PROJECT DATA 13 1The confidence level for specific statistics returns the confidence interval for a population mean. The confidence interval is a range on either side of a sampl

probability of rejecting the null hypothesis when it is true. If we assume alpha equals 0.05 we need to calculate the area under the standard normal curve that equals value is +1.96. The confidence interval is the sample mean +1.96 times the standard deviation divided by the square root of the number of data points.

Table 12. Statistical results summary for the Sediment Laboratory Quality-Assurance project, study number 96-2[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,200 milligrams omaterial was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Sample class 1 Sample class 2 Sa

Statistic

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-si

materi

mass

percen

differen

Mean -6.18 -9.08 18.76 0.41 -3.58 -9.47 13.54 3.36 -2.66 -6.22 Standard error 0.75 0.77 4.78 2.27 2.09 0.98 3.94 2.97 0.66 0.65 Median -5.05 -9.09 16.70 -2.45 -4.85 -9.24 14.69 -1.57 -1.87 -5.66 25th percentile -8.15 -10.49 5.23 -3.95 -6.41 -10.84 0.74 -3.97 -2.61 -6.56 75th percentile -3.24 -7.51 24.46 0.30 -2.99 -6.33 20.71 0.12 -1.46 -4.38 F-pseudosigma 3.64 2.21 14.25 3.16 2.54 3.34 14.80 3.03 0.85 1.6Standard deviation 4.11 3.10 19.12 12.43 11.66 4.02 16.24 16.54 3.49 2.69 Sample variance 16.93 9.59 365.52 154.45 135.93 16.18 263.68 273.73 12.20 7.23 Kurtosis 1.60 -0.32 0.23 9.68 24.71 1.18 0.71 6.39 5.77 1.73 Skewness -1.24 -0.20 0.60 3.11 4.65 -1.11 0.81 2.70 -1.27 -1.38 Range 18.72 10.27 72.87 56.55 73.95 14.12 60.28 66.89 20.67 10.53 Minimum -18.49 -14.30 -13.55 -12.25 -17.89 -18.99 -6.67 -8.08 -14.29 -13.10 Maximum 0.23 -4.03 59.32 44.30 56.06 -4.87 53.61 58.81 6.38 -2.57 Count 30.00 16.00 16.00 30.00 31.00 17.00 17.00 31.00 28.00 17.00 Confidence level

(95.0 percent)1

1.54 1.65 10.19 4.64 4.28 2.07 8.35 6.07 1.35 1.38 
14 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1The confidence level for specific statistics returns the confidence interval for a population mean. The confidence interval is a range on either side of a sampl

probability of rejecting the null hypothesis when it is true. If we assume alpha equals 0.05 we need to calculate the area under the standard normal curve that equals value is +1.96. The confidence interval is the sample mean +1.96 times the standard deviation divided by the square root of the number of data points.

Table 13. Statistical results summary for the Sediment Laboratory Quality-Assurance project, study number 97-1[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,200 milligrams omaterial was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Sample class 1 Sample class 2 Sa

Statistic

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-si

materi

mass

percen

differen

Mean -4.64 -7.15 10.86 -5.35 -7.09 -7.43 -2.15 -5.76 -2.12 -2.44 Standard error 0.61 0.78 2.27 1.31 1.49 0.64 4.80 1.82 0.71 0.80 Median -3.82 -5.93 8.28 -3.60 -4.92 -6.33 4.54 -3.38 -1.36 -1.67 25th percentile -5.68 -8.59 2.55 -5.34 -7.63 -9.11 -6.05 -6.62 -3.10 -3.275th percentile -2.22 -4.73 16.52 -1.31 -3.80 -5.10 7.26 -1.88 -0.79 -1.10 F-pseudosigma 2.56 2.86 10.36 2.98 2.84 2.98 9.87 3.51 1.71 1.57 Standard deviation 3.50 3.89 11.37 7.85 8.54 3.22 24.01 10.92 3.89 3.98 Sample variance 12.23 15.11 129.18 61.56 73.02 10.38 576.40 119.20 15.14 15.88 Kurtosis 3.02 2.07 0.03 4.06 23.96 -0.23 10.28 7.97 4.80 8.6Skewness -1.51 -1.50 0.92 -1.93 -4.62 -0.87 -2.87 -2.18 -0.91 -1.48 Range 16.13 16.66 37.79 38.82 50.47 10.69 123.24 66.77 22.57 24.85 Minimum -16.40 -18.45 -3.15 -31.57 -51.38 -14.27 -97.09 -50.30 -15.44 -17.0Maximum -0.27 -1.79 34.64 7.25 -0.91 -3.58 26.15 16.47 7.13 7.85 Count 33.00 25.00 25.00 36.00 33.00 25.00 25.00 36.00 30.00 25.00 Confidence level

(95.0 percent)1

1.24 1.60 4.69 2.65 3.03 1.33 9.91 3.69 1.45 1.64 
ANALYSIS AND INTERPRETATION OF PROJECT DATA 15 1The confidence level for specific statistics returns the confidence interval for a population mean. The confidence interval is a range on either side of a samp

probability of rejecting the null hypothesis when it is true. If we assume alpha equals 0.05 we need to calculate the area under the standard normal curve that equalvalue is +1.96. The confidence interval is the sample mean +1.96 times the standard deviation divided by the square root of the number of data points.

Table 14. Statistical results summary for the Sediment Laboratory Quality-Assurance project, study number 97-2[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,200 milligrams material was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Sample class 1 Sample class 2 Sa

Statistic

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-s

mater

mas

perce

differe

Mean -6.43 -6.43 12.62 -2.58 -5.49 -7.69 13.89 -4.47 -1.61 -2.3Standard error 2.55 1.04 6.98 1.10 0.47 0.70 6.32 0.50 0.32 0.3Median -4.54 -6.60 1.82 -2.91 -4.77 -6.73 1.46 -3.77 -1.38 -2.025th percentile -6.80 -8.93 -0.67 -5.28 -7.53 -9.55 -0.02 -6.43 -2.19 -2.275th percentile -2.98 -4.57 6.67 -1.89 -3.75 -4.74 7.03 -2.39 -1.08 -1.5F-pseudosigma 2.84 3.23 5.44 2.52 2.81 3.56 5.22 3.00 0.83 0.5Standard deviation 14.67 5.22 34.90 6.62 2.72 3.52 31.60 3.00 1.79 1.8Sample variance 215.23 27.28 1218.20 43.88 7.40 12.41 998.28 9.02 3.22 3.2Kurtosis 27.23 8.73 6.45 2.68 -0.39 3.12 4.97 0.29 10.02 16.1Skewness -4.94 2.27 2.49 0.82 -0.52 -1.29 2.33 -0.77 1.64 -3.8Range 95.22 27.48 162.32 35.81 9.91 16.81 134.82 12.77 11.83 9.5Minimum -84.63 -13.88 -27.00 -18.69 -11.32 -18.98 -18.54 -12.49 -6.02 -10.3Maximum 10.59 13.60 135.31 17.12 -1.41 -2.17 116.28 0.28 5.81 -0.7Count 33.00 25.00 25.00 36.00 33.00 25.00 25.00 36.00 32.00 25.0Confidence level

(95.0 percent)1

5.20 2.16 14.41 2.24 0.96 1.45 13.04 1.02 0.65 0.7
16 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1The confidence level for specific statistics returns the confidence interval for a population mean. The confidence interval is a range on either side of a sampl

probability of rejecting the null hypothesis when it is true. If we assume alpha equals 0.05 we need to calculate the area under the standard normal curve that equals value is +1.96. The confidence interval is the sample mean +1.96 times the standard deviation divided by the square root of the number of data points.

Table 15. Statistical results summary for the Sediment Laboratory Quality-Assurance project, study number 98-1[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,200 milligrams omaterial was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Sample class 1 Sample class 2 Sa

Statistic

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-size

material

mass

percent

difference

Sand-size

material

mass

percent

difference

Suspendedsediment

concentration percent

difference

Sediment

mass

percent

difference

Fine-si

materi

mass

percen

differen

Mean -5.67 -9.67 18.35 -7.34 -5.20 -7.99 15.96 -6.39 -1.30 -2.76 Standard error 0.52 1.55 6.03 1.20 0.50 1.17 7.14 0.93 1.87 1.10 Median -5.15 -7.81 7.08 -4.86 -4.82 -7.21 3.48 -5.48 -1.70 -2.125th percentile -7.03 -9.79 2.29 -8.38 -6.80 -8.27 1.01 -7.75 -3.14 -4.68 75th percentile -3.69 -5.49 14.18 -3.01 -3.16 -5.28 11.08 -2.34 -1.02 -1.26 F-pseudosigma 2.47 3.19 8.81 3.98 2.70 2.22 7.47 4.01 1.57 2.54 Standard deviation 3.08 7.57 29.52 7.67 2.98 5.74 34.96 5.96 11.06 5.40 Sample variance 9.49 57.37 871.47 58.80 8.90 32.91 1221.90 35.47 122.25 29.12 Kurtosis 4.07 11.82 3.70 2.37 0.96 13.58 12.93 1.77 26.14 9.12 Skewness -1.49 -3.20 2.04 -1.73 -0.33 -3.30 3.38 -1.38 4.70 2.22 Range 16.08 36.28 116.16 32.33 15.30 30.53 169.46 27.20 75.93 28.03 Minimum -16.98 -40.15 -5.71 -30.58 -13.23 -31.81 -9.86 -24.39 -17.84 -10.22 Maximum -0.90 -3.87 110.45 1.75 2.07 -1.28 159.60 2.81 58.09 17.8Count 35.00 24.00 24.00 41.00 35.00 24.00 24.00 41.00 35.00 24.00 Confidence level

(95.0 percent)1

1.06 3.20 12.47 2.42 1.03 2.42 14.76 1.88 3.80 2.28 
ANALYSIS AND INTERPRETATION OF PROJECT DATA 17

1Comments: Good (G) and marginal (M), refers to the condition of the sample upon arrival to the laboratory.

Table 16. Summary results for Sediment Laboratory Quality-Assurance studies in the Salinas, California, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; **, problems with samples, therefore, numbers not used in statistics; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-sand

material

mass

percent

differenc

96-1 A180993 CA A180993 151.00 N/A N/A 0.0500 0.0050 0.0530 0.0550 -3.55 0.0472 89.00 -5.66 

B1802693 CA B1802693 157.00 N/A N/A 0.0500 0.0078 0.0550 0.0578 -4.84 0.0473 86.00 -5.40 C1884693 CA C1884693 159.00 N/A N/A 0.0500 0.0097 0.0555 0.0597 -7.04 0.0461 83.00 -7.87 A1748293 CA A1748293 620.00 N/A N/A 0.1990 0.0202 0.2170 0.2192 -1.00 0.1931 89.00 -2.95 B17412393 CA B1741239 651.00 N/A N/A 0.1970 0.0319 0.2279 0.2289 -0.44 0.1937 85.00 -1.67 C17416693 CA C17416693 675.00 N/A N/A 0.2020 0.0419 0.2364 0.2439 -3.08 0.1915 81.00 -5.21 A1943393 CA A1943393 7460.00 N/A N/A 2.1880 0.4377 2.6121 2.6257 -0.52 2.1419 82.00 -2.11 B1947893 CA B1947893 7150.00 N/A N/A 2.1830 0.3272 2.5011 2.5102 -0.36 2.1509 86.00 -1.47 C195693 CA C195693 8440.00 N/A N/A 2.6760 0.2674 2.9261 2.9434 -0.59 2.6042 89.00 -2.68 

96-2 A1902393 CA A1902393 460.00 465.00 -1.08 0.1010 0.0153 0.1128 0.1163 -2.97 0.0936 83.00 -7.30 

B1903493 CA B1903493 442.00 444.40 -0.54 0.1010 0.0101 0.1070 0.1111 -3.69 0.0920 86.00 -8.89 C19011493 CA C19011493 290.00 285.35 1.63 0.0990 0.0151 0.1144 0.1141 0.23 0.0927 81.00 -6.40 A193293 CA A193293 1380.00 1380.32 -0.02 0.3000 0.0451 0.3387 0.3451 -1.85 0.2845 84.00 -5.16 B1933493 CA B1933493 1310.00 1306.80 0.24 0.2970 0.0297 0.3206 0.3267 -1.87 0.2821 88.00 -5.01 C1934993 CA C1934993 865.00 896.25 -3.49 0.2990 0.0595 0.3427 0.3585 -4.41 0.2844 83.00 -4.87 A1947693 CA A1947693 10400.00 9640.16 7.88 2.1910 0.2190 2.5639 2.4100 6.38 2.1024 82.00 -4.04 B195993 CA B195993 10700.00 12319.12 -13.14 2.6780 0.4018 2.6398 3.0798 -14.29 2.5606 97.00 -4.38 C1958093 CA C1958093 7960.00 8048.58 -1.10 2.6830 0.5364 3.1697 3.2194 -1.54 2.5675 81.00 -4.31 

97-1 CA_1_A0101 CA1A0101 247.00 252.00 -1.98 0.0575 0.0055 0.0616 0.0630 -2.22 0.0548 89.00 -4.65 

CA_1_B0238 CA1B0238 266.00 270.40 -1.63 0.0577 0.0099 0.0660 0.0676 -2.37 0.0548 83.00 -5.06 CA_1_C0357 CA1C0357 181.00 188.00 -3.72 0.0590 0.0162 0.0720 0.0752 -4.26 0.0554 77.00 -6.03 CA_2_A0101 CA2A0101 496.00 506.00 -1.98 0.1164 0.0101 0.1214 0.1265 -4.03 0.1105 91.00 -5.09 CA_2_B0239 CA2B0239 512.00 525.60 -2.59 0.1148 0.0166 0.1269 0.1314 -3.42 0.1091 86.00 -4.94 CA_2_C0357 CA2C0357 343.00 356.25 -3.72 0.1159 0.0266 0.1363 0.1425 -4.35 0.1090 80.00 -5.92 CA_3_A0101 CA3A1010 10800.00 10763.20 0.34 2.3003 0.3905 2.6515 2.6908 -1.46 2.2538 85.00 -2.02 CA_3_B0239 CA3B0239 11400.00 11414.80 -0.13 2.3012 0.5525 2.8061 2.8537 -1.67 2.2449 80.00 -2.45 CA_3_C5757 CA3C5757 7420.00 7560.00 -1.85 2.7003 0.3237 2.9684 3.0240 -1.84 2.6419 89.00 -2.16 

97-2 CA_1_A115 CA_1_A115 246.00 252.40 -2.54 0.0565 0.0066 0.0610 0.0631 -3.33 0.0549 90.00 -2.83 

CA_1_B1233 CA_1_B1233 265.00 278.00 -4.68 0.0592 0.0103 0.0655 0.0695 -5.76 0.0550 84.00 -7.06 CA_1_C1361 CA_1_C1361 177.00 188.50 -6.10 0.0585 0.0169 0.0701 0.0754 -7.03 0.0533 76.00 -8.93 CA_2_A115 CA_2_A115 465.00 499.20 -6.85 0.1163 0.0085 0.1154 0.1248 -7.53 0.1085 94.00 -6.73 CA_2_B1233 CA_2_B1233 511.00 532.80 -4.09 0.1162 0.0170 0.1251 0.1332 -6.08 0.1088 87.00 -6.34 CA_2_C1361 CA_2_C1361 343.00 356.50 -3.79 0.1147 0.0279 0.1357 0.1426 -4.84 0.1072 79.00 -6.54 CA_3_A115 CA_3_A115 10800.00 10766.00 0.32 2.3002 0.3910 2.6646 2.6915 -1.00 2.2649 85.00 -1.53 CA_3_B1233 CA_3_B1233 11500.00 11410.00 0.79 2.3001 0.5520 2.8282 2.8525 -0.85 2.2626 80.00 -1.63 CA_3_C1361 CA_3_C1361 6480.00 6565.50 -1.30 2.3014 0.3240 2.5807 2.6262 -1.73 2.2710 88.00 -1.32 

98-1 CA_1_A4717 CA_1_A4717 176.00 182.86 -3.75 0.0569 0.0071 0.0612 0.0640 -4.38 0.0539 88.00 -5.35 

CA_1_B4856 CA_1_B4856 162.00 167.75 -3.43 0.0580 0.0091 0.0645 0.0671 -3.87 0.0548 85.00 -5.47 CA_1_C4973 CA_1_C4973 220.00 238.67 -7.82 0.0566 0.0150 0.0654 0.0716 -8.66 0.0510 78.00 -9.87 CA_2_A8228 CA_2_A8228 347.00 356.29 -2.61 0.1156 0.0091 0.1207 0.1247 -3.21 0.1110 92.00 -3.94 CA_2_B8145 CA_2_B8145 322.00 334.25 -3.66 0.1175 0.0162 0.1276 0.1337 -4.56 0.1110 87.00 -5.52 CA_2_C8084 CA_2_C8084 446.00 473.00 -5.71 0.1147 0.0272 0.1329 0.1419 -6.34 0.1050 79.00 -8.46 CA_3_A0617 CA_3_A0917 7600.00 7682.86 -1.08 2.2991 0.3899 2.6477 2.6890 -1.54 2.2505 85.00 -2.11 CA_3_B5756 CA_3_B 8060.00 8124.75 -0.80 2.6988 0.5511 3.2167 3.2499 -1.02 2.6699 83.00 -1.07 CA_3_C5873 CA_3_C5873 10100.00 10078.33 0.21 2.7005 0.3230 2.9991 3.0235 -0.81 2.6692 89.00 -1.16 

Median -1.98 -3.08 -5.06 25th percentile -3.73 -4.39 -6.19 75th percentile -0.60 -1.50 -2.31 F-pseudosigmaInterquartile range

2.32 2.14 2.88 3.13 2.89 3.88 
18 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1Comments: Good (G) and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 17. Summary results for Sediment Laboratory Quality-Assurance studies in the Honolulu, Hawaii, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-sand

material

mass

percent

difference

96-1 A1884293 --- --- N/A N/A 0.0490 0.0050 --- 0.0540 --- --- --- --- 

B1885593 --- --- N/A N/A 0.0500 0.0080 --- 0.0580 --- --- --- --- C1886393 --- --- N/A N/A 0.0500 0.0106 --- 0.0606 --- --- --- --- A1746293 --- --- N/A N/A 0.2020 0.0209 --- 0.2229 --- --- --- --- B17415893 HI B17415893 633.00 N/A N/A 0.1970 0.0294 0.2194 0.2264 -3.10 --- --- --- C17417693 HI C17417693 646.00 N/A N/A 0.1970 0.0404 0.2251 0.2374 -5.18 --- --- --- A194393 --- --- N/A N/A 2.2040 0.4425 --- 2.6465 --- --- --- --- B1947493 HI B1947493 6730.00 N/A N/A 2.1960 0.3290 2.3330 2.5250 -7.60 --- --- --- C1955093 HI C1955093 8410.00 N/A N/A 2.6960 0.2673 2.9140 2.9633 -1.66 --- --- --- 

96-2 A1905593 HI A1905593 455.00 464.76 -2.10 0.1010 0.0152 0.1093 0.1162 -5.93 --- --- --- 

B19013893 HI B19013893 450.00 439.92 2.29 0.1000 0.0100 0.1072 0.1100 -2.53 --- --- --- C19019893 HI C19019893 291.00 303.00 -3.96 0.1010 0.0202 0.1146 0.1212 -5.45 --- --- --- A1936993 HI A1936993 1370.00 1385.92 -1.15 0.3010 0.0455 0.3333 0.3465 -3.80 --- --- --- B19315393 HI B1935393 1290.00 1320.48 -2.31 0.3000 0.0301 0.3128 0.3301 -5.25 --- --- --- C19318793 HI C19318793 884.00 895.95 -1.33 0.2990 0.0594 0.3492 0.3584 -2.56 --- --- --- A1944293 HI A1941293 9350.00 9597.44 -2.58 2.1810 0.2184 --- 2.3994 --- --- --- --- B1951893 HI B1951893 11800.00 12305.04 -4.10 2.6750 0.4013 --- 3.0763 --- --- --- --- C1956793 HI C1956793 7400.00 8100.23 -8.64 2.7000 0.5401 --- 3.2401 --- --- --- --- 

97-1 HI_1_A0402 HI_1_A0402 244.00 255.60 -4.54 0.0584 0.0055 0.0603 0.0639 -5.63 --- --- --- 

HI_1_B0538 HI_1_B0538 261.00 274.80 -5.02 0.0584 0.0103 0.0648 0.0687 -5.68 --- --- --- HI_1_C0658 HI_1_C0658 180.00 186.50 -3.49 0.0584 0.0162 0.0693 0.0746 -7.10 --- --- --- HI_2_A0402 HI_2_A0402 484.00 504.40 -4.04 0.1160 0.0101 0.1199 0.1261 -4.92 --- --- --- HI_2_B0538 HI_2_B0538 514.00 528.00 -2.65 0.1152 0.0168 0.1240 0.1320 -6.06 --- --- --- HI_2_C0658 HI_2_C0658 342.00 353.25 -3.18 0.1145 0.0268 0.1340 0.1413 -5.17 --- --- --- HI_3_A0302 HI_3_A0302 9890.00 10764.00 -8.12 2.2999 0.3911 0.2346 2.6910 --- --- --- --- HI_3_B0438 HI_3_B0438 11000.00 11402.40 -3.53 2.2986 0.5520 0.2767 2.8506 --- --- --- --- HI_3_C5858 HI_3_C5858 7240.00 7560.75 -4.24 2.7007 0.3236 0.1699 3.0243 --- --- --- --- 

97-2 HI_1_A146 HI_1_A146 258.00 264.40 -2.42 0.0592 0.0069 0.0631 0.0661 -4.54 --- --- --- 

HI_1_B1534 HI_1_B1534 261.00 268.00 -2.61 0.0565 0.0105 0.0103 0.0670 -84.63 --- --- --- HI_1_C1662 HI_1_C1662 170.00 186.25 -8.72 0.0589 0.0156 0.0667 0.0745 -10.47 --- --- --- HI_2_A146 none 482.00 494.80 -2.59 0.1147 0.0090 0.1182 0.1237 -4.45 --- --- --- HI_2_B1534 HI_2_B1534 523.00 536.40 -2.50 0.1169 0.0172 0.1288 0.1341 -3.95 --- --- --- HI_2_C1662 HI_2_C1662 346.00 356.25 -2.88 0.1164 0.0261 0.1361 0.1425 -4.49 --- --- --- HI_3_A146 HI_3_A146 10500.00 10772.80 -2.53 2.3014 0.3910 2.5900 2.6932 -3.83 --- --- --- HI_3_B1534 HI_3_B1534 10800.00 11411.20 -5.36 2.2999 0.5520 2.6810 2.8528 -6.02 --- --- --- HI_3_C1662 HI_3_C1662 6280.00 6557.75 -4.24 2.2999 0.3240 2.5000 2.6231 -4.69 --- --- --- 

98-1 HI_1_A5018 HI_1_A5018 178.00 185.43 -4.01 0.0578 0.0071 0.0612 0.0649 -5.70 --- --- --- 

HI_1_B5155 HI_1_B5155 159.00 169.25 -6.06 0.0585 0.0092 0.0630 0.0677 -6.94 --- --- --- HI_1_C5274 HI_1_C5274 241.00 249.00 -3.21 0.0587 0.0160 0.0713 0.0747 -4.55 --- --- --- HI_2_A7927 HI_2_A7927 352.00 355.43 -0.96 0.1145 0.0099 0.1214 0.1244 -2.41 --- --- --- HI_2_B7846 HI_2_B7846 320.00 329.25 -2.81 0.1159 0.0158 0.1274 0.1317 -3.26 --- --- --- HI_2_C7783 HI_2_C7783 459.00 474.33 -3.23 0.1168 0.0255 0.1359 0.1423 -4.50 --- --- --- HI_3_A1018 HI_3_A1018 7080.00 7689.14 -7.92 2.3000 0.3912 2.4736 2.6912 -8.09 --- --- --- HI_3_B5955 HI_3_B5955 7440.00 8128.75 -8.47 2.6997 0.5518 2.9932 3.2515 -7.94 --- --- --- HI_3_C6074 HI_3_C6074 10000.00 10079.67 -0.79 2.7004 0.3235 2.9726 3.0239 -1.70 --- --- --- 

Median -3.22 -5.0425th percentile -4.32 -6.0075th percentile -2.52 -3.86F-pseudosigmaInterquartile range

1.33 1.581.79 2.14
ANALYSIS AND INTERPRETATION OF PROJECT DATA 19

1Comments: Good (G), marginal (M), and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 18. Summary results for Sediment Laboratory Quality-Assurance studies in the Iowa City, Iowa, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-san

materia

mass

percent

differenc

96-1 A18811893 IA A18811893 145.00 N/A N/A 0.0490 0.0052 0.0506 0.0542 -6.64 0.0438 86.56 -10.61 

B18815893 IA B18815893 155.00 N/A N/A 0.0500 0.0081 0.0548 0.0581 -5.68 0.0452 82.48 -9.60 C18815893 IA C 18817093 161.00 N/A N/A 0.0500 0.0099 0.0564 0.0599 -5.89 0.0453 80.32 -9.40 A17413693 IA A17413693 592.00 N/A N/A 0.1970 0.0191 0.2080 0.2161 -3.75 0.1840 88.46 -6.60 B17416893 IA B17416893 599.00 N/A N/A 0.1970 0.0306 0.2130 0.2276 -6.41 0.1781 83.62 -9.59 C17417393 IA C17417393 642.00 N/A N/A 0.1970 0.0413 0.2262 0.2383 -5.08 0.1802 79.66 -8.53 A1943293 IA A1943293 7520.00 N/A N/A 2.1810 0.4371 2.6207 2.6181 0.10 2.1338 81.42 -2.17 B1956093 IA B1956093 8820.00 N/A N/A 2.6750 0.4018 3.0458 3.0768 -1.01 2.5862 84.91 -3.32 C1956393 IA C1956393 8460.00 N/A N/A 2.6750 0.2675 2.9420 2.9425 -0.02 2.6166 88.94 -2.18 

96-2 A1903793 IA A1930793 449.30 469.32 -4.27 0.1020 0.0153 0.1104 0.1173 -5.91 --- --- --- 

B19010093 IA B19010093 435.60 444.28 -1.95 0.1010 0.0101 0.1062 0.1111 -4.38 --- --- --- C19017493 IA C19017493 294.50 302.95 -2.79 0.1010 0.0202 0.1165 0.1212 -3.86 --- --- --- A19310493 IA A19310493 1369.40 1365.32 0.30 0.2970 0.0443 0.3351 0.3413 -1.83 --- --- --- B19312193 IA B19312193 1315.30 1325.24 -0.75 0.3010 0.0303 0.3237 0.3313 -2.30 --- --- --- C19314793 IA C19314793 884.20 894.40 -1.14 0.2980 0.0598 0.3496 0.3578 -2.28 --- --- --- A1945393 IA A19545393 9695.00 9666.04 0.30 2.1970 0.2195 2.3880 2.4165 -1.18 --- --- --- B1952793 IA B1952793 12278.80 12311.16 -0.26 2.6760 0.4018 3.0403 3.0778 -1.22 --- --- --- C1955793 IA C1955793 8063.40 7985.90 0.97 2.6620 0.5324 3.2004 3.1944 0.19 --- --- --- 

97-1 IA_1_A0703 IA_2_A0703 255.00 250.40 1.84 0.0571 0.0055 0.0616 0.0626 -1.60 0.0561 91.04 -1.79 

IA_1_B0837 IA_1_B0837 259.00 272.80 -5.06 0.0583 0.0099 0.0644 0.0682 -5.57 0.0539 83.70 -7.54 IA_1_C0959 IA_1_C0959 176.00 185.00 -4.86 0.0584 0.0156 0.0697 0.0740 -5.81 0.0545 78.19 -6.68 IA_2_A0703 IA_1_A0703 437.00 501.60 -12.88 0.1150 0.0104 0.1083 0.1254 -13.64 0.0986 91.04 -14.26 IA_2_B0837 IA_I_B0837B 497.00 534.80 -7.07 0.1172 0.0165 0.1233 0.1337 -7.78 0.1071 86.86 -8.62 IA_2_C0959 IA_2_C0959 347.00 352.50 -1.56 0.1145 0.0265 0.1381 0.1410 -2.06 0.1104 79.94 -3.58 IA_3_A0503 IA_3_A0503 10400.00 10768.00 -3.42 2.3015 0.3905 2.5991 2.6920 -3.45 2.2134 85.16 -3.83 IA_3_B0637 IA_3_B0637 10800.00 11402.00 -5.28 2.2988 0.5517 2.6626 2.8505 -6.59 2.2709 85.29 -1.21 IA_3_C5959 IA_3_C5959 7560.00 7562.00 -0.03 2.7012 0.3236 3.0057 3.0248 -0.63 2.6811 89.20 -0.74 

97-2 IA_1_A177 IA_1_A177 250.00 256.80 -2.65 0.0571 0.0071 0.0619 0.0642 -3.58 0.0544 87.88 -4.73 

IA_1_B1835 IA_1_B1835 271.00 276.80 -2.10 0.0590 0.0102 0.0669 0.0692 -3.32 0.0563 84.16 -4.57 IA_1_C1963 IA_1_C1963 178.00 184.25 -3.39 0.0590 0.0147 0.0704 0.0737 -4.48 0.0558 79.26 -5.43 IA_2_A177 IA_2_A177 492.00 504.40 -2.46 0.1173 0.0088 0.1217 0.1261 -3.49 0.1129 92.77 -3.75 IA_2_B1835 IA_2_B1835 522.00 533.60 -2.17 0.1167 0.0167 0.1284 0.1334 -3.75 0.1112 86.60 -4.72 IA_2_C1963 IA_2_C1963 351.00 358.25 -2.02 0.1155 0.0278 0.1388 0.1433 -3.14 0.1102 79.39 -4.59 IA_3_A177 IA_3_A177 10600.00 10762.40 -1.51 2.2990 0.3910 2.6374 2.6906 -1.98 2.2471 85.20 -2.26 IA_3_B1835 IA_3_B1835 11300.00 11408.40 -0.95 2.3009 0.5520 2.8015 2.8521 -1.77 2.2496 80.30 -2.23 IA_3_C1963 IA_3_C1963 6530.00 6560.75 -0.47 2.3008 0.3240 2.5998 2.6243 -0.93 2.2748 87.50 -1.13 

98-1 IA_1_A5319 IA_1_A5319 185.00 188.57 -1.89 0.0589 0.0071 0.0645 0.0660 -2.27 0.0566 87.69 -3.97 

IA_1_B5454 IA_1_B5454 147.00 147.56 -0.38 0.0568 0.0096 0.0658 0.0664 -0.90 0.0546 82.98 -3.87 IA_1_C5575 IA_1_C5575 241.00 249.00 -3.21 0.0583 0.0164 0.0719 0.0747 -3.75 0.0551 76.63 -5.49 IA_2_A7626 IA_2_A7626 354.00 360.29 -1.74 0.1175 0.0086 0.1232 0.1261 -2.30 0.1135 92.13 -3.40 IA_2_B7547 IA_2_B7547 332.00 339.50 -2.21 0.1174 0.0184 0.1319 0.1358 -2.87 0.1118 84.76 -4.77 IA_2_C7482 IA_2_C7482 459.00 473.33 -3.66 0.1149 0.0271 0.1370 0.1420 -3.52 0.1091 79.64 -5.04 IA_3_A4719 IA_3_A4719 7670.00 7693.14 -0.30 2.3010 0.3916 2.6766 2.6926 -0.59 2.2847 85.36 -0.71 IA_3_B6154 IA_3_B6154 8140.00 8124.00 0.20 2.6986 0.5510 3.2380 3.2496 -0.36 2.6853 82.93 -0.49 IA_3_C6275 IA_3_C6275 10200.00 10093.33 1.06 2.7039 0.3241 3.0002 3.0280 -0.92 2.6747 89.15 -1.08 

Median -1.92 -3.14 -4.27 25th percentile -3.26 -4.48 -6.62 75th percentile -0.36 -1.22 -2.22 F-pseudosigmaInterquartile range

2.15 2.42 3.26 2.90 3.26 4.40 
20 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1Comments: Good (G), marginal (M), and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 19. Summary results for Sediment Laboratory Quality-Assurance studies in the Louisville, Kentucky, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-san

materia

mass

percent

differenc

96-1 A18817793 KYA18817793 179.00 N/A N/A 0.0490 0.0050 0.0540 0.0540 0.00 0.0368 68.15 -24.90 

B18818793 KYB18818793 213.00 N/A N/A 0.0490 0.0101 0.0593 0.0591 0.34 0.0456 76.90 -6.94 C18819793 KYC18819793 203.00 N/A N/A 0.0490 0.0070 0.0546 0.0560 -2.50 0.0451 82.60 -7.96 A1741693 KY A1741693 710.00 N/A N/A 0.1990 0.0200 0.2125 0.2190 -2.97 0.1853 87.20 -6.88 B17412693 KY B17412693 869.00 N/A N/A 0.1970 0.0293 0.2250 0.2263 -0.57 0.1881 83.60 -4.52 C17418893 KY C17418893 911.00 N/A N/A 0.1980 0.0408 0.2351 0.2388 -1.55 0.1860 79.12 -6.05 A1944493 KY A1944493 10700.00 N/A N/A 2.1820 0.4361 2.5901 2.6181 -1.07 2.0959 80.92 -3.95 B1946393 KY B1946393 8890.00 N/A N/A 2.1870 0.3276 2.4979 2.5146 -0.66 2.0895 83.65 -4.46 C1951493 KY C1951493 10300.00 N/A N/A 2.6840 0.2683 2.9360 2.9523 -0.55 2.5643 87.34 -4.46 

96-2 A190493 KYA190493 480.20 455.32 5.46 0.0990 0.0148 0.1106 0.1138 -2.84 --- --- --- 

B1901393 KYB1901393 442.70 444.44 -0.39 0.1010 0.0101 0.1054 0.1111 -5.14 --- --- --- C1906993 KYC1906993 293.55 297.05 -1.18 0.0990 0.0198 0.1156 0.1188 -2.71 0.0915 79.15 -7.58 A1933193 KYA1933193 1353.90 1375.48 -1.57 0.2990 0.0449 0.3321 0.3439 -3.42 --- --- B1934193 KYB1934193 1398.30 1328.96 5.22 0.3020 0.0302 0.3156 0.3322 -5.01 --- --- C1939193 KYC1939193 900.00 900.05 -0.01 0.3000 0.0600 0.3513 0.3600 -2.42 0.2810 79.99 -6.33 A1946493 KYA1946493 9594.39 9605.32 -0.11 2.1830 0.2183 2.3701 2.4013 -1.30 --- --- --- B1951693 KYB1951693 12701.79 12406.56 2.38 2.6970 0.4046 3.0434 3.1016 -1.88 --- --- --- C1953193 KYC1953193 8123.67 8028.18 1.19 2.6760 0.5353 3.1626 3.2113 -1.52 2.5326 80.08 -5.36 

97-1 KY_1_A1004 KY_1_A1004 246.00 255.60 -3.76 0.0582 0.0057 0.0608 0.0639 -4.85 0.0532 87.50 -8.59 

KY_1_B1136 KY_1_B1136 273.00 275.60 -0.94 0.0590 0.0099 0.0676 0.0689 -1.89 0.0554 81.95 -6.10 KY_1_C1260 KY_1_C1260 177.00 184.50 -4.07 0.0575 0.0163 0.0702 0.0738 -4.88 0.0522 74.36 -9.22 KY_2_A1004 KY_2_A1004 475.00 504.00 -5.75 0.1159 0.0101 0.1177 0.1260 -6.59 0.1054 89.55 -9.06 KY_2_B1136 KY_2_B1136 511.00 527.20 -3.07 0.1153 0.0165 0.1257 0.1318 -4.63 0.1080 85.92 -6.33 KY_2_C1260 KY_2_C1260 365.00 357.75 2.03 0.1159 0.0272 0.1398 0.1431 -2.31 0.1114 79.69 -3.88 KY_3_A0704 KY_3_A0704 10700.00 10764.00 -0.59 2.3002 0.3908 2.6413 2.6910 -1.85 2.2264 84.29 -3.2KY_3_B0836 KY_3_B0836 11500.00 11413.20 0.76 2.3015 0.5518 2.7954 2.8533 -2.03 2.2232 79.53 -3.40 KY_3_C6060 KY_3_C6060 7340.00 7556.75 -2.87 2.6990 0.3237 2.9644 3.0227 -1.93 2.6146 88.20 -3.13 

97-2 KY_1_A208 KY_1_A208 253.00 258.40 -2.09 0.0581 0.0065 0.0626 0.0646 -3.10 0.0557 88.98 -4.13 

KY_1_B2136 KY_1_B2136 262.00 272.00 -3.68 0.0575 0.0105 0.0650 0.0680 -4.41 0.0537 82.62 -6.60 KY_1_C2264 KY_1_C2264 182.00 186.75 -2.54 0.0595 0.0152 0.0720 0.0747 -3.61 0.0569 79.03 -4.37 KY_2_A208 KY_2_A208 473.00 496.00 -4.64 0.1154 0.0086 0.1174 0.1240 -5.32 0.1082 92.16 -6.24 KY_2_B2136 KY_2_B2136 509.00 528.80 -3.74 0.1167 0.0155 0.1263 0.1322 -4.46 0.1113 88.12 -4.63 KY_2_C2264 KY_2_C2264 349.00 356.00 -1.97 0.1161 0.0263 0.1380 0.1424 -3.09 0.1106 80.14 -4.74 KY_3_A208 KY_3_A208 10700.00 10764.40 -0.60 2.2990 0.3910 2.6541 2.6911 -1.37 2.2613 85.20 -1.64 KY_3_B2136 KY_3_B2136 11300.00 11403.20 -0.91 2.3002 0.5520 2.8140 2.8508 -1.29 2.2771 80.92 -1.00 KY_3_C2264 KY_3_C2264 6630.00 6561.75 1.04 2.2999 0.3240 2.5813 2.6247 -1.65 2.2545 87.34 -1.97 

98-1 KY_1_A5620 KY_1_A5620 183.00 189.43 -3.39 0.0590 0.0073 0.0637 0.0663 -3.92 0.0558 87.60 -5.42 

KY_1_B5753 KY_1_B5753 156.00 166.25 -6.17 0.0568 0.0097 0.0619 0.0665 -6.92 0.0518 83.68 -8.8KY_1_C5876 KY_1_C5876 235.00 247.00 -4.86 0.0575 0.0166 0.0698 0.0741 -5.80 0.0529 75.79 -8.00 KY_2_A7325 KY_2_A7325 343.00 363.14 -5.55 0.1172 0.0099 0.1192 0.1271 -6.22 0.1090 91.44 -7.00 KY_2_B7248 KY_2_B7248 308.00 328.75 -6.31 0.1156 0.0159 0.1224 0.1315 -6.92 0.1064 86.93 -7.96 KY_2_C7181 KY_2_C7181 464.00 469.00 -1.07 0.1148 0.0259 0.1328 0.1407 -5.61 0.1059 79.74 -7.76 KY_3_A4820 KY_3_A4820 7510.00 7692.57 -2.37 2.3016 0.3908 2.6146 2.6924 -2.89 2.2449 85.86 -2.46 KY_3_B6353 KY_3_B6353 7990.00 8138.75 -1.83 2.7037 0.5518 3.1795 3.2555 -2.33 2.6368 82.93 -2.48 KY_3_C6476 KY_3_C6476 9340.00 10079.33 -7.34 2.6996 0.3242 2.7828 3.0238 -7.97 2.4606 88.42 -8.85 

Median -1.90 -2.84 -6.05 25th percentile -3.75 -4.85 -7.67 75th percentile -0.32 -1.65 -4.04 F-pseudosigmaInterquartile range

2.54 2.37 2.69 3.43 3.20 3.63 
ANALYSIS AND INTERPRETATION OF PROJECT DATA 21

1Comments: Good (G) and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 20. Summary results for Sediment Laboratory Quality-Assurance studies in the Baton Rouge, Louisiana, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-sand

material

mass

percent

difference

96-1 A18816493 LA A18816493 152.00 N/A N/A 0.0500 0.0050 0.0538 0.0550 -2.24 0.0467 86.84 -6.56 

B18817693 LA B18817693 159.00 N/A N/A 0.0490 0.0074 0.0561 0.0564 -0.53 0.0466 83.02 -4.95 C18812693 LA C18812693 161.00 N/A N/A 0.0500 0.0100 0.0553 0.0600 -7.83 0.0440 79.50 -12.07 A17413393 LA A17413393 599.00 N/A N/A 0.1970 0.0202 0.2099 0.2172 -3.36 0.1836 87.48 -6.79 B17415393 LA B17415393 645.00 N/A N/A 0.1970 0.0309 0.2183 0.2279 -4.21 0.1824 83.56 -7.41 C17415993 LA C17415993 658.00 N/A N/A 0.2010 0.0399 0.2304 0.2409 -4.36 0.1856 80.55 -7.67 A1946093 LA A1946093 7292.00 N/A N/A 2.1820 0.4358 2.5078 2.6178 -4.20 2.0298 80.94 -6.97 B195393 LA B195393 9104.00 N/A N/A 2.6790 0.4016 2.9742 3.0806 -3.45 2.5233 84.84 -5.81 C1956993 LA C1956993 8101.00 N/A N/A 2.6760 0.2680 2.8798 2.9440 -2.18 2.5676 89.16 -4.05 

96-2 A1901293 LA A1901293 412.00 450.84 -8.62 0.0980 0.0147 0.0970 0.1127 -13.94 0.0843 86.89 -14.00 

B19010693 LA B19010693 410.00 447.20 -8.32 0.1010 0.0108 0.0975 0.1118 -12.79 0.0866 88.78 -14.30 C19017393 LA C19017393 298.00 297.05 0.32 0.0990 0.0198 0.1165 0.1188 -1.95 0.0950 81.54 -4.05 A1931893 LA A1931893 1277.00 1384.60 -7.77 0.3010 0.0452 0.2908 0.3462 -15.99 0.2484 85.43 -17.46 B19310993 LA B19310993 1453.00 1307.08 11.16 0.2970 0.0298 0.2683 0.3268 -17.89 0.2406 89.68 -18.99 C19317493 LA C19317493 862.00 896.58 -3.86 0.2990 0.0596 0.3403 0.3586 -5.11 0.2775 81.55 -7.19 A1942293 LA A1942293 9432.00 9619.12 -1.95 2.1860 0.2188 2.2759 2.4048 -5.36 2.0401 89.64 -6.67 B195793 LA B195793 11158.00 12333.12 -9.53 2.6810 0.4023 2.7539 3.0833 -10.68 2.3298 84.60 -13.10 C1956693 LA C1956693 8044.00 8102.35 -0.72 2.7000 0.5409 3.1743 3.2409 -2.06 2.5944 81.73 -3.91 

97-1 LA_1_A1305 LA_1_A1305 238.00 255.20 -6.74 0.0578 0.0060 0.0586 0.0638 -8.15 0.0524 89.50 -9.26 

LA_1_B1435 LA_1_B1435 269.00 274.40 -1.97 0.0582 0.0104 0.0660 0.0686 -3.79 0.0552 83.64 -5.15 LA_1_C1561 LA_1_C1561 173.00 186.75 -7.36 0.0586 0.0161 0.0727 0.0747 -2.68 0.0559 76.88 -4.62 LA_2_A1305 LA_2_A1305 486.00 505.20 -3.80 0.1166 0.0097 0.1114 0.1263 -11.80 0.1041 93.42 -10.75 LA_2_B1435 LA_2_B1435 532.00 533.60 -0.30 0.1169 0.0165 0.1154 0.1334 -13.49 0.1002 86.84 -14.27 LA_2_C1561 LA_2_C1561 412.00 353.75 16.47 0.1148 0.0267 0.1307 0.1415 -7.63 0.1041 79.61 -9.36 LA_3_A0905 LA_3_A0905 10492.00 10758.80 -2.48 2.2988 0.3909 2.5475 2.6897 -5.29 2.1682 85.11 -5.68 LA_3_B1035 LA_3_B1305 10625.00 11404.40 -6.83 2.2995 0.5516 2.4109 2.8511 -15.44 1.9085 79.16 -17.01 LA_3_C6161 LA_3_C6161 8786.00 7560.00 16.22 2.7006 0.3234 2.8686 3.0240 -5.14 2.5422 88.62 -5.87 

97-2 LA_1_A239 LA_1_A239 241.00 252.80 -4.67 0.0572 0.0060 0.0589 0.0632 -6.80 0.0526 89.30 -8.05 

LA_1_B2437 LA_1_B2437 266.00 274.00 -2.92 0.0576 0.0109 0.0636 0.0685 -7.15 0.0525 82.55 -8.85 LA_1_C2565 LA_1_C2565 176.00 181.25 -2.90 0.0575 0.0150 0.0691 0.0725 -4.69 0.0539 78.00 -6.26 LA_2_A239 LA_2_A239 478.00 506.80 -5.68 0.1171 0.0096 0.1176 0.1267 -7.18 0.1081 91.92 -7.69 LA_2_B2437 LA_2_B2437 511.00 529.60 -3.51 0.1169 0.0155 0.1214 0.1324 -8.31 0.1062 87.48 -9.15 LA_2_C2565 LA_2_C2565 346.00 356.75 -3.01 0.1147 0.0280 0.1359 0.1427 -4.77 0.1079 79.40 -5.92 LA_3_A239 LA_3_A239 10551.00 10759.60 -1.94 2.2989 0.3910 2.6290 2.6899 -2.26 2.2352 85.02 -2.77 LA_3_B2437 LA_3_B2437 11363.00 11406.80 -0.38 2.3008 0.5520 2.7870 2.8517 -2.27 2.2396 80.36 -2.66 LA_3_C2565 LA_3_C2565 6475.00 6558.00 -1.27 2.2994 0.3240 2.5610 2.6232 -2.37 2.2373 87.36 -2.70 

98-1 LA_1_A5921 LA_1_A5921 191.00 187.71 1.75 0.0585 0.0072 0.0643 0.0657 -2.13 0.0545 84.76 -6.84 

LA_1_B6052 LA_1_B6052 166.00 167.50 -0.90 0.0580 0.0090 0.0641 0.0670 -4.33 0.0541 84.40 -6.72 LA_1_C6177 LA_1_C6177 246.00 244.67 0.54 0.0581 0.0153 0.0717 0.0734 -2.32 0.0552 76.99 -4.99 LA_2_A7024 LA_2_A7024 341.00 362.29 -5.88 0.1173 0.0095 0.1176 0.1268 -7.26 0.1086 92.35 -7.41 LA_2_B6949 LA_2_B6949 324.00 331.75 -2.34 0.1160 0.0167 0.1263 0.1327 -4.82 0.1097 86.86 -5.43 LA_2_C6880 LA_2_C6880 460.00 477.00 -3.56 0.1172 0.0259 0.1364 0.1431 -4.68 0.1110 81.38 -5.29 LA_3_A4921 LA_3_A4921 7144.00 7689.71 -7.10 2.2996 0.3918 2.5048 2.6914 -6.93 2.2060 88.07 -4.07 LA_3_B6552 LA_3_B6552 8095.00 8124.00 -0.36 2.6986 0.5510 3.1854 3.2496 -1.98 3.1793 99.81 17.81 LA_3_C6677 LA_3_C6677 10118.00 10073.33 0.44 2.6987 0.3233 2.9676 3.0220 -1.80 2.6421 89.03 -2.10 

Median -2.69 -4.77 -6.72 25th percentile -5.73 -7.63 -9.15 75th percentile -0.38 -2.37 -4.99 F-pseudosigmaInterquartile range

3.97 3.90 3.09 5.35 5.26 4.16 
22 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1Comments: Good (G) and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 21. Summary results for Sediment Laboratory Quality-Assurance studies in the Rolla, Missouri, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-san

materia

mass

percent

differenc

96-1 A18811393 MO A18811393 315.00 N/A N/A 0.0500 0.0051 0.0547 0.0551 -0.73 0.0464 84.83 -7.20 

B18812393 MO B18812393 319.00 N/A N/A 0.0490 0.0069 0.0528 0.0559 -5.55 0.0435 82.39 -11.22 C18816693 MO C18816693 353.00 N/A N/A 0.0490 0.0112 0.0594 0.0602 -1.33 0.0456 76.77 -6.94 A1749393 MO A1749393 1300.00 N/A N/A 0.2010 0.0203 0.2209 0.2213 -0.18 0.1935 87.60 -3.73 B17412293 MO B17412293 1350.00 N/A N/A 0.1980 0.0314 0.2291 0.2294 -0.13 0.1892 82.60 -4.43 C17414893 MO C17414893 1440.00 N/A N/A 0.1990 0.0406 0.2369 0.2396 -1.13 0.1900 80.20 -4.53 A1945993 MO A 1945993 16200.00 N/A N/A 2.1800 0.4357 2.6167 2.6157 0.04 2.0934 80.00 -3.97 B194793 MO B194793 15100.00 N/A N/A 2.2010 0.3301 2.5402 2.5311 0.36 2.1084 83.00 -4.2C1954193 MO C1954193 16200.00 N/A N/A 2.7110 0.2714 2.9748 2.9824 -0.25 2.5881 87.00 -4.53 

96-2 A1904293 --- --- 450.92 --- 0.0980 0.0147 --- 0.1127 --- --- --- --- 

B1908093 --- --- 444.20 --- 0.1010 0.0101 --- 0.1111 --- --- --- --- C19010293 MO C19010293 286.00 296.30 -3.48 0.0990 0.0195 0.1128 0.1185 -4.83 0.0898 79.61 -9.29 A1938793 --- --- 1366.20 --- 0.2970 0.0446 --- 0.3416 --- --- --- --- B19313493 --- --- 1324.60 --- 0.3010 0.0302 --- 0.3312 --- --- --- --- C19317293 MO C19317293 855.00 899.78 -4.98 0.3000 0.0599 0.3363 0.3599 -6.56 0.2719 80.85 -9.37 A1942493 --- --- 9636.36 --- 2.1900 0.2191 --- 2.4091 --- --- --- --- B1951293 --- --- 12310.24 --- 2.6760 0.4016 --- 3.0776 --- --- --- --- C1954693 MO C1954693 8000.00 8067.23 -0.83 2.6890 0.5379 3.1701 3.2269 -1.76 2.5215 79.54 -6.23 

97-1 MO_1_A1106 MO_1_A1606 253.00 252.40 0.24 0.0570 0.0061 0.0629 0.0631 -0.32 --- --- --- 

MO_1_B1234 MO_1_B1734 258.00 271.20 -4.87 0.0574 0.0104 0.0664 0.0678 -2.06 --- --- --- MO_1_C6262 MO_1_C1862 186.00 184.25 0.95 0.0573 0.0164 0.0735 0.0737 -0.27 0.0544 74.01 -5.07 MO_2_A1606 MO_2_A1606 498.00 502.80 -0.95 0.1155 0.0102 0.1199 0.1257 -4.61 --- --- --- MO_2_B1734 MO_2_B1734 516.00 524.80 -1.68 0.1145 0.0167 0.1274 0.1312 -2.90 --- --- --- MO_2_C1862 MO_2_C1862 360.00 358.75 0.35 0.1161 0.0274 0.1422 0.1435 -0.91 0.1116 78.48 -3.88 MO_3_A1106 MO_3_A1106 10771.00 10768.40 0.02 2.3012 0.3909 2.6619 2.6921 -1.12 --- --- --- MO_3_B1234 MO_3_B1234 11201.00 11414.40 -1.87 2.3015 0.5521 2.6597 2.8536 -6.79 --- --- --- MO_3_C6262 MO_3_C6262 7533.00 7560.00 -0.36 2.7006 0.3234 2.9954 3.0240 -0.95 --- --- -1.40 

97-2 MO_1_A2610 MO_1_A2610 284.00 256.80 10.59 0.0574 0.0068 0.0690 0.0642 7.48 0.0530 76.81 -7.67 

MO_1_B2738 MO_1_B2738 275.00 268.00 2.61 0.0569 0.0101 0.0680 0.0670 1.49 0.0490 72.06 -13.88 MO_1_C2866 MO_1_C2866 185.00 183.00 1.09 0.0577 0.0155 0.0730 0.0732 -0.27 0.0540 73.97 -6.42 MO_2_A2610 MO_2_A2610 502.00 503.20 -0.24 0.1169 0.0089 0.1240 0.1258 -1.43 0.1070 86.29 -8.47 MO_2_B2738 MO_2_B2738 527.00 532.40 -1.01 0.1171 0.0160 0.1310 0.1331 -1.58 0.1040 79.39 -11.19 MO_2_C2866 MO_2_C2866 356.00 355.00 0.28 0.1146 0.0274 0.1400 0.1420 -1.41 0.1050 75.00 -8.38 MO_3_A2610 MO_3_A2610 10711.00 10764.40 -0.50 2.2988 0.3910 2.6600 2.6911 -1.16 2.2480 84.51 -2.2MO_3_B2738 MO_3_B2738 11380.00 11404.80 -0.22 2.2994 0.5520 2.8250 2.8512 -0.92 2.2329 79.04 -2.89 MO_3_C2866 MO_3_C2866 6542.00 6561.25 -0.29 2.3015 0.3240 2.5950 2.6245 -1.12 2.2501 86.71 -2.23 

98-1 MO_1_A6222 MO_1_A6222 183.00 186.00 -1.61 0.0583 0.0068 0.0636 0.0651 -2.30 0.0536 84.28 -8.06 

MO_1_B6351 MO_1_B6351 162.00 165.50 -2.11 0.0565 0.0097 0.0644 0.0662 -2.72 0.0482 74.84 -14.70 MO_1_C6478 MO_1_C6478 244.00 249.00 -2.01 0.0578 0.0169 0.0725 0.0747 -2.95 0.0534 73.66 -7.6MO_2_A6723 MO_2_A6723 355.00 360.29 -1.47 0.1171 0.0090 0.1230 0.1261 -2.46 0.1089 88.54 -7.00 MO_2_B6650 MO_2_B6650 348.00 338.50 2.81 0.1174 0.0180 0.1382 0.1354 2.07 0.1159 83.86 -1.28 MO_2_C6579 MO_2_C6579 471.00 471.33 -0.07 0.1158 0.0256 0.1396 0.1414 -1.27 0.1063 76.15 -8.20 MO_3_A5022 MO_3_A5022 7683.00 7694.86 -0.15 2.3022 0.3910 2.6731 2.6932 -0.75 2.2684 84.86 -1.47 MO_3_B6751 MO_3_B6751 8037.00 8102.00 -0.80 2.6892 0.5516 3.2011 3.2408 -1.23 2.6425 82.55 -1.74 MO_3_C6878 MO_3_C6878 10064.00 10058.00 0.06 2.6939 0.3235 2.9894 3.0174 -0.93 2.6555 88.83 -1.43 

Median -0.33 -1.13 -6.23 25th percentile -1.58 -2.18 -8.20 75th percentile 0.19 -0.30 -3.73 F-pseudosigmaInterquartile range

1.31 1.40 3.32 1.77 1.89 4.47 
ANALYSIS AND INTERPRETATION OF PROJECT DATA 23

1Comments: Good (G) and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 22. Summary results for Sediment Laboratory Quality-Assurance studies in the Helena, Montana, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-sand

material

mass

percent

difference

96-1 A18813393 MT A18813393 145.00 N/A N/A 0.0490 0.0053 0.0508 0.0543 -6.45 0.0442 87.00 -9.80 

B18813693 MT B18813693 156.00 N/A N/A 0.0500 0.0082 0.0547 0.0582 -6.01 0.0449 82.00 -10.29 C18814493 MT C18814493 162.00 N/A N/A 0.0490 0.0108 0.0566 0.0598 -5.35 0.0453 80.00 -7.59 A1742493 MT A1742493 594.00 N/A N/A 0.2010 0.0200 0.2080 0.2210 -5.90 0.1830 88.00 -8.94 B1744993 MT B1744993 612.00 N/A N/A 0.1990 0.0297 0.2142 0.2287 -6.34 0.1778 83.00 -10.66 C17413293 MT C17413293 638.00 N/A N/A 0.1970 0.0397 0.2234 0.2367 -5.62 0.1787 80.00 -9.28 A1946993 MT A1946993 7360.00 N/A N/A 2.2200 0.4445 2.5755 2.6645 -3.34 2.0862 81.00 -6.03 B1947993 MT B1947993 6950.00 N/A N/A 2.1840 0.3279 2.4341 2.5119 -3.10 2.0446 84.00 -6.38 C1952493 MT C1952493 8170.00 N/A N/A 2.6800 0.2679 2.8612 2.9479 -2.94 2.5179 88.00 -6.05 

96-2 A1904993 MT A1904993 431.00 466.20 -7.55 0.1010 0.0156 0.1064 0.1166 -8.71 0.0872 82.00 -13.62 

B19018793 MT B19018793 --- 794.00 --- 0.1000 0.0985 --- 0.1985 --- --- --- --- C19012793 MT C19012793 283.00 293.68 -3.63 0.0980 0.0195 0.1125 0.1175 -4.23 0.0900 80.00 -8.16 A1934293 MT A1934293 1310.00 1366.68 -4.15 0.2970 0.0447 0.3226 0.3417 -5.58 0.2678 83.00 -9.85 B1938993 MT B1938993 1260.00 1324.60 -4.88 0.3010 0.0302 0.3092 0.3312 -6.63 0.2690 87.00 -10.63 C19312393 MT C19312393 866.00 899.98 -3.78 0.3000 0.0600 0.3440 0.3600 -4.44 0.2752 80.00 -8.27 A1941493 MT A1941493 9480.00 9615.12 -1.41 2.1850 0.2188 2.3467 2.4038 -2.37 2.0416 87.00 -6.56 B1951993 MT B1951993 12200.00 12345.96 -1.18 2.6840 0.4025 3.0144 3.0865 -2.34 2.5321 84.00 -5.66 C1954793 MT C1954793 8090.00 8111.45 -0.26 2.7040 0.5406 3.1884 3.2446 -1.73 2.5507 80.00 -5.67 

97-1 MT_1_A1907 MT_1_A1907 251.00 254.40 -1.34 0.0581 0.0055 0.0615 0.0636 -3.30 0.0554 90.00 -4.73 

MT_1_B2033 MT_1_B2033 265.00 272.80 -2.86 0.0586 0.0096 0.0657 0.0682 -3.67 0.0552 84.00 -5.82 MT_1_C2163 MT_1_C2163 178.00 182.00 -2.20 0.0568 0.0160 0.0707 0.0728 -2.88 0.0530 75.00 -6.65 MT_2_A1907 MT_2_A1907 486.00 502.40 -3.26 0.1160 0.0096 0.1211 0.1256 -3.58 0.1090 90.00 -6.04 MT_2_B2033 MT_2_B2033 518.00 536.80 -3.50 0.1171 0.0171 0.1291 0.1342 -3.80 0.1110 86.00 -5.19 MT_2_C2163 MT_2_C2163 344.00 355.50 -3.23 0.1151 0.0271 0.1359 0.1422 -4.43 0.1074 79.00 -6.72 MT_3_A1307 MT_3_A1307 10900.00 10765.20 1.25 2.3004 0.3909 2.6693 2.6913 -0.82 2.2689 85.00 -1.37 MT_3_B1433 MT_3_B1433 11500.00 11412.00 0.77 2.3011 0.5519 2.8252 2.8530 -0.97 --- --- -1.78 MT_3_C6363 MT_3_C6363 7540.00 7560.25 -0.27 2.7003 0.3238 3.0098 3.0241 -0.47 2.6787 89.00 -0.80 

97-2 MT_1_A2911 MT_1_A2911 246.00 264.40 -6.96 0.0588 0.0073 0.0607 0.0661 -8.17 0.0534 88.00 -9.16 

MT_1_B3039 MT_1_B3039 256.00 276.00 -7.25 0.0580 0.0110 0.0625 0.0690 -9.42 0.0519 83.00 -10.56 MT_1_C3167 MT_1_C3167 174.00 183.75 -5.31 0.0578 0.0157 0.0685 0.0735 -6.80 0.0527 77.00 -8.75 MT_2_A2911 MT_2_A2911 484.00 512.40 -5.54 0.1173 0.0108 0.1205 0.1281 -5.93 0.1097 91.00 -6.52 MT_2_B3039 MT_2_B3039 501.00 528.80 -5.26 0.1164 0.0158 0.1217 0.1322 -7.94 0.1059 87.00 -9.04 MT_2_C3167 MT_2_C3167 334.00 358.00 -6.70 0.1171 0.0261 0.1324 0.1432 -7.54 0.1059 80.00 -9.55 MT_3_A2911 MT_3_A2911 10800.00 10760.80 0.36 2.2996 0.3910 2.6673 2.6902 -0.85 2.2672 85.00 -1.41 MT_3_B3039 MT_3_B3039 11400.00 11411.60 -0.10 2.2996 0.5520 2.8300 2.8529 -0.80 2.2640 80.00 -1.55 MT_3_C3167 MT_3_C3167 6510.00 6563.75 -0.82 2.3016 0.3240 2.5965 2.6255 -1.10 2.2590 87.00 -1.85 

98-1 MT_1_A6523 MT_1_A6523 184.00 189.71 -3.01 0.0593 0.0071 0.0628 0.0664 -5.42 0.0553 88.00 -6.81 

MT_1_B6650 MT_1_B6650 163.00 173.25 -5.92 0.0584 0.0109 0.0643 0.0693 -7.22 0.0534 83.00 -8.61 MT_1_C6779 MT_1_C6779 229.00 246.00 -6.91 0.0584 0.0154 0.0681 0.0738 -7.72 0.0524 77.00 -10.21 MT_2_A6422 MT_2_A6422 340.00 359.71 -5.48 0.1163 0.0096 0.1179 0.1259 -6.35 0.1073 91.00 -7.75 MT_2_B6351 MT_2_B6351 313.00 333.25 -6.08 0.1149 0.0184 0.1244 0.1333 -6.68 0.1057 85.00 -7.97 MT_2_C6278 MT_2_C6278 442.00 472.67 -6.49 0.1153 0.0265 0.1318 0.1418 -7.05 0.1054 80.00 -8.55 MT_3_A5123 MT_3_A5123 7570.00 7695.71 -1.63 2.3023 0.3912 2.6574 2.6935 -1.34 2.2588 85.00 -1.89 MT_3_B6950 MT_3_B6950 8100.00 8124.50 -0.30 2.6987 0.5511 3.2096 3.2498 -1.24 2.6640 83.00 -1.29 MT_3_C7079 MT_3_C7079 9550.00 10082.00 -5.28 2.7003 0.3243 2.9219 3.0246 -3.40 2.6005 89.00 -3.70 

Median -3.50 -4.44 -6.76 25th percentile -5.51 -6.49 -9.07 75th percentile -1.26 -2.76 -5.54 F-pseudosigmaInterquartile range

3.15 2.77 2.61 4.25 3.73 3.53 
24 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1Comments: Good (G) and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 23. Summary results for Sediment Laboratory Quality-Assurance studies in the Albuquerque, New Mexico, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-san

materia

mass

percen

differen

96-1 A18811493 NM A18811493 142.00 N/A N/A 0.0490 0.0051 0.0499 0.0541 -7.76 0.0429 86.00 -12.4

B18812293 NM B18812293 162.00 N/A N/A 0.0500 0.0082 0.0568 0.0582 -2.41 0.0460 81.00 -7.9C18819493 NM C18819493 169.00 N/A N/A 0.0490 0.0105 0.0591 0.0595 -0.67 0.0443 75.00 -9.5A1745293 NM A1745293 592.00 N/A N/A 0.1990 0.0200 0.2073 0.2190 -5.34 0.1762 85.00 -11.4B1749893 NM B1749893 623.00 N/A N/A 0.2010 0.0302 0.2180 0.2312 -5.71 0.1788 82.00 -11.0C17418393 NM C17418393 623.00 N/A N/A 0.1980 0.0402 0.2182 0.2382 -8.40 0.1702 78.00 -14.0A194893 NM A194893 7300.00 N/A N/A 2.1920 0.4381 2.5557 2.6301 -2.83 1.9423 76.00 -11.3B1948093 NM B1948093 7090.00 N/A N/A 2.2190 0.3335 2.4828 2.5525 -2.73 1.9614 79.00 -11.6C1957793 NM C1957793 8310.00 N/A N/A 2.7100 0.2709 2.8825 2.9809 -3.30 2.4213 84.00 -10.6

96-2 A190893 NM A190893 433.00 450.72 -3.93 0.0980 0.0147 0.1071 0.1127 -4.95 0.0889 83.00 -9.2

B19011893 NM B19011893 429.00 444.56 -3.50 0.1010 0.0101 0.1077 0.1111 -3.10 0.0915 85.00 -9.3C19015393 NM C19015393 307.00 305.98 0.33 0.1020 0.0204 0.1178 0.1224 -3.75 0.0942 80.00 -7.6A1933993 NM A1933993 1265.00 1376.24 -8.08 0.2990 0.0451 0.3186 0.3441 -7.40 0.2644 83.00 -11.5B19311293 NM B19311293 1252.00 1322.92 -5.36 0.3000 0.0307 0.3147 0.3307 -4.85 0.2675 85.00 -10.8C19316193 NM C19316193 866.00 906.10 -4.43 0.3020 0.0604 0.3474 0.3624 -4.15 0.2744 79.00 -9.1A1943693 NM A1943693 9586.00 9593.12 -0.07 2.1800 0.2183 2.3708 2.3983 -1.15 2.0389 86.00 -6.4B1953993 NM B1953993 12134.00 12428.92 -2.37 2.7020 0.4052 3.0515 3.1072 -1.79 2.4107 79.00 -10.7C1956593 NM C1956593 9182.00 8026.68 14.39 2.6750 0.5357 3.1329 3.2107 -2.42 2.4123 77.00 -9.8

97-1 NM_1_A2208 NM_1_A2208 275.00 256.40 7.25 0.0585 0.0056 0.0580 0.0641 -9.52 0.0505 87.00 -13.7

NM_1_B2332 NM_1_B2332 271.00 270.40 0.22 0.0578 0.0098 0.0659 0.0676 -2.51 0.0554 84.00 -4.2NM_1_C2464 NM_1_C2464 161.00 183.75 -12.38 0.0576 0.0159 0.0668 0.0735 -9.12 0.0508 76.00 -11.8NM_2_A2208 NM A1933993 547.00 497.60 9.93 0.1146 0.0098 0.1191 0.1244 -4.26 0.1084 91.00 -5.4NM_2_B2332 NM_2_B2332 522.00 532.40 -1.95 0.1165 0.0166 0.1262 0.1331 -5.18 0.1085 86.00 -6.8NM_2_C2464 NM_2_C2464 326.00 356.00 -8.43 0.1159 0.0265 0.1349 0.1424 -5.27 0.1066 79.00 -8.0NM_3_A1508 NM_3_A1508 10756.00 10759.20 -0.03 2.2990 0.3908 2.5794 2.6898 -4.10 2.1667 84.00 -5.7NM_3_B1632 NM_3_B1632 11509.00 11404.80 0.91 2.2996 0.5516 2.8635 2.8512 0.43 2.2908 80.00 -0.3NM_3_C6464 NM_3_C6464 7455.00 7555.00 -1.32 2.6987 0.3233 2.9986 3.0220 -0.77 2.6688 89.00 -1.1

97-2 NM_1_A3212 NM_1_A3212 284.00 262.00 8.40 0.0580 0.0075 0.0637 0.0655 -2.75 0.0510 80.00 -12.1

NM_1_B3340 NM_1_B3340 254.00 274.80 -7.57 0.0581 0.0106 0.0629 0.0687 -8.44 0.0503 80.00 -13.3NM_1_C3468 NM_1_C3468 173.00 182.00 -4.95 0.0574 0.0154 0.0683 0.0728 -6.18 0.0519 76.00 -9.5NM_2_A3212 NM_2_A3212 453.00 505.20 -10.33 0.1173 0.0090 0.1145 0.1263 -9.34 0.0950 83.00 -18.9NM_2_B3340 NM_2_B3340 524.00 528.40 -0.83 0.1160 0.0161 0.1245 0.1321 -5.75 0.1046 84.00 -9.8NM_2_C3468 NM_2_C3468 325.00 352.75 -7.87 0.1153 0.0258 0.1346 0.1411 -4.61 0.1036 77.00 -10.1NM_3_A3212 --- --- 10766.80 --- 2.3002 0.3910 0.0000 2.6917 --- --- --- --- NM_3_B3340 NM_3_B3340 10942.00 11404.00 -4.05 2.3002 0.5520 2.7508 2.8510 -3.51 2.0631 75.00 -10.3NM_3_C3468 NM_3_C3468 6483.00 6560.25 -1.18 2.2994 0.3240 2.5880 2.6241 -1.38 2.1998 85.00 -4.3

98-1 NM_1_A6824 NM_1_A6824 162.00 182.86 -11.41 0.0567 0.0073 0.0577 0.0640 -9.84 0.0444 77.00 -21.6

NM_1_B6949 NM_1_B6949 142.00 172.25 -17.56 0.0583 0.0106 0.0572 0.0689 -16.98 0.0349 61.00 -40.1NM_1_C7080 NM_1_C7080 218.00 240.33 -9.29 0.0575 0.0146 0.0662 0.0721 -8.18 0.0497 75.00 -13.6NM_2_A6121 NM_2_A6121 330.00 357.71 -7.75 0.1155 0.0097 0.1178 0.1252 -5.91 0.1025 87.00 -11.2NM_2_B6052 NM_2_B6052 303.00 333.50 -9.15 0.1175 0.0159 0.1214 0.1334 -9.00 0.0801 66.00 -31.8NM_2_C5977 NM_2_C5977 448.00 469.67 -4.61 0.1154 0.0255 0.1367 0.1409 -2.98 0.1094 80.00 -5.2NM_3_A5224 NM_3_A5224 7316.00 7690.86 -4.87 2.3017 0.3901 2.6190 2.6918 -2.70 2.0690 79.00 -10.1NM_3_B7149 NM_3_B7149 8124.00 8131.25 -0.09 2.7010 0.5515 3.2068 3.2525 -1.41 2.5013 78.00 -7.3NM_3_C7280 NM_3_C7280 9826.00 10076.67 -2.49 2.6988 0.3242 2.9722 3.0230 -1.68 2.6155 88.00 -3.0

Median -3.93 -4.21 -10.125th percentile -7.81 -6.49 -11.675th percentile -0.08 -2.66 -7.5F-pseudosigmaInterquartile range

5.73 2.84 3.07.73 3.83 4.1
ANALYSIS AND INTERPRETATION OF PROJECT DATA 25

1Comments: Good (G), marginal (M), and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 24. Summary results for Sediment Laboratory Quality-Assurance studies in the Ithaca, New York (contract) laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-sand

material

mass

percent

differenc

97-1 NY_1_A3412 NY_1_A3412 189.00 256.00 -26.17 0.0579 0.0061 --- 0.0640 --- --- --- --- 

NY_1_B3528 NY_1_B3528 192.90 252.40 -23.57 0.0566 0.0065 --- 0.0631 --- --- --- --- NY_1_C3668 NY_1_C366? 125.40 183.25 -31.57 0.0578 0.0155 --- 0.0733 --- --- --- --- NY_2_A3412 NY_2_A3412 397.20 507.60 -21.75 0.1168 0.0101 --- 0.1269 --- --- --- --- NY_2_B3528 NY_2_B3528 396.20 499.20 -20.63 0.1149 0.0099 --- 0.1248 --- --- --- --- NY_2_C3668 NY_2_C3668 248.20 354.25 -29.94 0.1147 0.0270 --- 0.1417 --- --- --- --- NY_3_A2613 NY_3_A2613 8820.10 10762.00 -18.04 2.2991 0.3914 --- 2.6905 --- --- --- --- NY_3_B2726 NY_3_B2726 8637.30 10762.00 -19.74 2.3000 0.3905 --- 2.6905 --- --- --- --- NY_3_C6868 NY?? --- 7728.75 --- 2.7003 0.3912 --- 3.0915 --- --- --- --- 

97-2 NY_1_A4416 NY_1_A4416 224.00 263.60 -15.02 0.0592 0.0067 --- 0.0659 --- --- --- --- 

NY_1_B4544 NY_1_B4544 228.00 280.40 -18.69 0.0590 0.0111 --- 0.0701 --- --- --- --- NY_1_C4672 NY_1_C4672 219.90 187.75 17.12 0.0583 0.0168 --- 0.0751 --- --- --- --- NY_2_A4416 NY_2_A4416 440.00 502.80 -12.49 0.1168 0.0089 --- 0.1257 --- --- --- --- NY_2_B4544 NY_2_B4544 440.00 531.60 -5.57 0.1167 0.0162 --- 0.1329 --- --- --- --- NY_2_C4672 NY_2_C4672 331.90 356.00 -6.77 0.1168 0.0256 --- 0.1424 --- --- --- --- NY_3_A4416 NY_3_A4416 10730.00 10765.20 -0.33 2.3007 0.3910 --- 2.6913 --- --- --- --- NY_3_B4544 NY_3_B4544 11362.00 11408.00 -0.40 2.2996 0.3910 --- 2.8520 --- --- --- --- NY_3_C4672 NY_3_C4672 7940.00 6558.50 21.06 2.3003 0.3240 --- 2.6234 --- --- --- --- 

98-1 NY_1_A7125 NY_1_A7125 132.00 182.00 -27.47 0.0577 0.0060 --- 0.0637 --- --- --- --- 

NY_1_B7248 NY_1_B7248 136.00 169.75 -19.88 0.0574 0.0105 --- 0.0679 --- --- --- --- NY_1_C7281 NY_1_C7381 168.00 242.00 -30.58 0.0575 0.0151 --- 0.0726 --- --- --- --- NY_1_A7125 NY_1_A7125 136.00 182.00 -25.27 0.0577 0.0060 --- 0.0637 --- --- --- --- NY_1_B7248 NY_1_B7248 152.00 169.75 -10.46 0.0574 0.0105 --- 0.0679 --- --- --- --- NY_1_C7281 NY_1_C7281 188.00 242.00 -22.31 0.0575 0.0151 --- 0.0726 --- --- --- --- NY_2_A5820 WA_2_A4917 288.00 357.71 -19.49 0.1158 0.0094 --- 0.1252 --- --- --- --- NY_2_B5753 WA_2_B4856 248.00 328.00 -24.39 0.1146 0.0166 --- 0.1312 --- --- --- --- NY_2_C5676 WA_2_C4773 376.00 477.67 -21.28 0.1166 0.0267 --- 0.1433 --- --- --- --- NY_2_A5820 WA_2_A4917 312.00 357.71 -12.78 0.1158 0.0094 --- 0.1252 --- --- --- --- NY_2_B5753 WA_2_B4856 280.00 328.00 -14.63 0.1146 0.0166 --- 0.1312 --- --- --- --- NY_2_C5676 WA_2_C4773 400.00 477.67 -16.26 0.1166 0.0267 --- 0.1433 --- --- --- --- NY_3_A5325 NY_3_A5325 6160.00 7694.57 -19.94 2.3019 0.3912 --- 2.6931 --- --- --- --- NY_3_B7348 NY_3_B7348 6992.00 8132.75 -14.03 2.7013 0.5518 --- 3.2531 --- --- --- --- NY_3_C7481 NY_3_C7481 10312.00 10089.00 2.21 2.7020 0.3247 --- 3.0267 --- --- --- --- NY_3_A5325 NY_3_C5325 6708.00 7694.57 -12.82 2.3019 0.3912 --- 2.6931 --- --- --- --- NY_3_B7348 NY_3_C7348 7580.00 8132.75 -6.80 2.7013 0.5518 --- 3.2531 --- --- --- --- NY_3_C7481 NY_3_C7481 10860.00 10089.00 7.64 2.7020 0.3247 --- 3.0267 --- --- --- --- 

Median -18.0425th percentile -22.0375th percentile -8.63F-pseudosigmaInterquartile range

9.94

13.41
26 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1Comments: Good (G), marginal (M), and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 25. Summary results for Sediment Laboratory Quality-Assurance studies in the Columbus, Ohio (contract) laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-sand

material

mass

percent

difference

96-1 A18814793 OH A18814793 138.00 N/A N/A 0.0510 0.0051 0.0484 0.0561 -13.76 --- --- --- 

B18817493 OH B18817493 131.90 N/A N/A 0.0490 0.0073 0.0462 0.0563 -17.89 --- --- --- C18819093 OH C18819093 151.70 N/A N/A 0.0510 0.0110 0.0532 0.0620 -14.24 --- --- --- A1749593 OH A1749593 587.50 N/A N/A 0.2010 0.0201 0.2055 0.2211 -7.05 --- --- --- B17416293 OH B17416293 611.50 N/A N/A 0.1980 0.0307 0.2142 0.2287 -6.36 --- --- --- C17417893 OH C17417893 609.00 N/A N/A 0.2000 0.0405 0.2136 0.2405 -11.20 --- --- --- A1942793 OH A1942793 6877.70 N/A N/A 2.2150 0.4439 1.4610 2.6589 -45.05 --- --- --- B194693 OH B194693 6695.20 N/A N/A 2.1890 0.3284 2.3340 2.5174 -7.28 --- --- --- C1955193 OH C1955193 7892.30 N/A N/A 2.6980 0.2703 2.7623 2.9683 -6.94 --- --- --- 

96-2 A1907193 OH A1907193 403.90 460.28 -12.25 0.1000 0.0151 0.0938 0.1151 -18.49 --- --- --- 

B19015893 OH B19015893 406.70 431.64 -5.78 0.0980 0.0099 0.0982 0.1079 -9.03 --- --- --- C19019693 OH C19019693 310.40 303.05 2.43 0.1010 0.0202 0.1062 0.1212 -12.39 --- --- --- A1931293 OH A1931293 1325.70 1370.00 -3.23 0.2980 0.0445 0.3245 0.3245 -5.25 --- --- --- B1935893 OH B1935893 1281.70 1336.12 -4.07 0.3030 0.0310 0.3897 0.3340 -7.29 --- --- --- C19319693 OH C19319693 956.50 903.25 5.90 0.3010 0.0603 0.3387 0.3613 -6.26 --- --- --- A1944893 OH A1944893 9588.60 9715.92 -1.31 2.2080 0.2210 2.3291 2.4290 -4.11 --- --- --- B1953293 OH B1953293 11747.60 12305.16 -4.53 2.6750 0.4013 2.8993 3.0763 -5.75 --- --- --- C1956493 OH C1956493 8012.10 8121.23 -1.34 2.7070 0.5415 3.1688 3.2485 -2.45 --- --- --- 

97-1 OH_1_A2509 OH_1_A2509 246.60 255.20 -3.37 0.0582 0.0056 0.0609 0.0638 -4.55 --- --- --- 

OH_1_B2631 OH_1_B2631 260.10 277.20 -6.17 0.0588 0.0105 0.0645 0.0693 -6.93 --- --- --- OH_1_C2765 OH_1_C2765 174.20 181.75 -4.15 0.0572 0.0155 0.0688 0.0727 -5.36 --- --- --- OH_2_A2509 OH_2_A2509 485.90 507.60 -4.28 0.1174 0.0095 0.1205 0.1269 -5.04 --- --- --- OH_2_B2631 OH_2_B2631 513.40 532.00 -3.50 0.1163 0.0167 0.1279 0.1330 -3.83 --- --- --- OH_2_C2765 OH_2_C2765 345.40 359.00 -3.79 0.1165 0.0271 0.1361 0.1436 -5.22 --- --- --- OH_3_A1709 OH_3_A1709 10682.00 10758.00 -0.71 2.2990 0.3905 2.6705 2.6895 -0.71 --- --- --- OH_3_B1831 OH_3_B18? 11452.00 11406.40 0.40 2.2993 0.5523 2.7944 2.8516 -2.01 --- --- --- OH_3_C6565 OH_3_C6565 7499.50 7556.75 -0.76 2.6986 0.3241 2.9848 3.0227 -1.25 --- --- --- 

97-2 OH_1_A3513 OH_1_A3513 249.00 262.80 -5.25 0.0589 0.0068 0.0615 0.0657 -6.39 --- --- --- 

OH_1_B3641 OH_1_B3641 272.60 272.80 -0.07 0.0577 0.0105 0.0676 0.0682 -0.88 --- --- --- OH_1_C3769 OH_1_C3769 183.10 184.50 -0.76 0.0593 0.0145 0.0724 0.0738 -1.90 --- --- --- OH_2_A3513 OH_2_A3513 480.80 497.60 -3.38 0.1152 0.0092 0.1190 0.1244 -4.34 --- --- --- OH_2_B3641 OH_2_B3641 499.20 537.60 -7.14 0.1161 0.0183 0.1221 0.1344 -9.15 --- --- --- OH_2_C3769 OH_2_C3769 344.70 362.25 -4.84 0.1173 0.0276 0.1362 0.1449 -6.00 --- --- --- OH_3_A3513 OH_3_A3513 10600.00 10760.80 -1.49 2.3002 0.3910 2.6606 2.6902 -1.10 --- --- --- OH_3_B3641 OH_3_B3641 11263.60 11408.80 -1.27 2.3017 0.5520 2.8159 2.8522 -1.27 --- --- --- OH_3_C3769 OH_3_C3769 6457.50 6559.50 -1.55 2.2995 0.3240 2.5750 2.6238 -1.86 --- --- --- 

98-1 OH_1_A7426 OH_1_A7426 173.80 184.29 -5.69 0.0580 0.0065 0.0602 0.0645 -6.67 --- --- --- 

OH_1_B7547 OH_1_B7547 162.20 172.25 -5.83 0.0588 0.0101 0.0640 0.0689 -7.11 --- --- --- OH_1_C7682 OH_1_C7682 242.00 247.67 -2.29 0.0592 0.0151 0.0716 0.0743 -3.63 --- --- --- OH_2_A5519 OH_2_A5519 332.50 357.71 -7.05 0.1152 0.0100 0.1153 0.1252 -7.91 --- --- --- OH_2_B5454 OH_2_B5454 287.00 328.75 -12.70 0.1149 0.0166 0.1141 0.1315 -13.23 --- --- --- OH_2_C5375 OH_2_C5375 473.10 477.33 -0.89 0.1157 0.0275 0.1377 0.1432 -3.84 --- --- --- OH_3_A5426 OH_3_A5426 7553.20 7694.86 -1.84 2.3019 0.3913 2.6391 2.6932 -2.01 --- --- --- OH_3_B7547 OH_3_B8132 8041.70 8145.25 -1.27 2.7063 0.5518 3.2020 3.2581 -1.72 --- --- --- OH_3_C7682 OH_3_C8359 10010.10 10099.67 -0.89 2.7054 0.3245 2.9830 3.0299 -1.55 --- --- --- 

Median -3.30 -5.7525th percentile -4.95 -7.2975th percentile -1.18 -2.45F-pseudosigmaInterquartile range

2.80 3.593.77 4.84
ANALYSIS AND INTERPRETATION OF PROJECT DATA 27

1Comments: Good (G), marginal (M), and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 26. Summary results for Sediment Laboratory Quality-Assurance studies in the Guaynabo, Puerto Rico, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-sand

material

mass

percent

difference

96-1 A18812493 PR A18812493 169.20 N/A N/A 0.0500 0.0051 0.0605 0.0551 9.80 0.0575 95.00 14.95 

B18818293 PR B18818293 165.90 N/A N/A 0.0500 0.0080 0.0581 0.0580 0.17 0.0501 86.20 0.16 C18819393 PR C18819393 169.30 N/A N/A 0.0490 0.0101 0.0495 0.0591 -16.24 0.0413 83.50 -15.65 A1746393 PR A1746393 613.20 N/A N/A 0.1990 0.0202 0.2149 0.2192 -1.96 0.1923 89.50 -3.35 B17414593 PR B17414593 648.80 N/A N/A 0.1990 0.0313 0.2271 0.2303 -1.39 0.1976 87.00 -0.72 C17414693 PR C17414693 671.10 N/A N/A 0.2000 0.0408 0.2349 0.2408 -2.45 0.1912 81.40 -4.40 A1944393 PR A1944393 7400.00 N/A N/A 2.1930 0.4387 2.5945 2.6317 -1.41 2.3766 91.60 8.37 B1944693 PR B1944693 7084.00 N/A N/A 2.1800 0.3276 2.4817 2.5076 -1.03 2.2087 89.00 1.32 C1955493 PR C1955493 8275.00 N/A N/A 2.6750 0.2685 2.8995 2.9435 -1.49 2.7081 93.40 1.24 

96-2 A190293 PRA190293 664.00 460.16 44.30 0.1000 0.0150 0.1055 0.1150 -8.29 0.0897 85.00 -10.33 

B1901193 PRB1901193 633.10 440.08 43.86 0.1000 0.0100 0.0989 0.1100 -10.11 0.0890 90.00 -10.99 C1902893 PRC1902893 294.80 294.05 0.26 0.0980 0.0196 0.1147 0.1176 -2.48 0.0941 82.00 -4.03 A1934493 PRA1934493 1978.30 1393.88 41.93 0.3030 0.0455 0.3114 0.3485 -10.64 0.2678 86.00 -11.62 B1933893 PRB1933893 2008.00 1311.32 53.13 0.2980 0.0298 0.3005 0.3278 -8.34 0.2705 90.00 -9.24 C1935293 PRC1935293 893.00 903.03 -1.11 0.3010 0.0602 0.3469 0.3612 -3.96 0.2845 82.00 -5.50 A1945293 PRA1945293 12639.00 9719.84 30.03 2.2090 0.2210 2.3323 2.4300 -4.02 2.0991 89.00 -4.98 B1951393 PRB1951393 15966.00 12304.88 29.75 2.6750 0.4012 2.9815 3.0762 -3.08 2.5343 85.00 -5.26 C1952393 PRC1952393 8403.00 8172.18 2.82 2.7240 0.5449 3.2365 3.2689 -0.99 2.6539 82.00 -2.57 

97-1 PR_1_A2810 PR_1_A2810 244.00 251.60 -3.02 0.0574 0.0055 0.0605 0.0629 -3.82 0.0547 90.41 -4.71 

PR_1_B2930 PR_1_B2930 257.00 302.40 -15.01 0.0656 0.0100 0.0632 0.0756 -16.40 0.0535 84.65 -18.45 PR_1_C3066 PR_1_C3066 161.00 182.00 -11.54 0.0569 0.0159 0.0639 0.0728 -12.23 0.0485 75.90 -14.76 PR_2_A2810 PR_2_A2810 468.00 500.40 -6.47 0.1153 0.0098 0.1137 0.1251 -9.11 0.1048 92.17 -9.11 PR_2_B2930 PR_2_B2930 487.00 527.60 -7.70 0.1153 0.0166 0.1177 0.1319 -10.77 0.1021 86.75 -11.44 PR_2_C3066 PR_2_C3066 346.00 355.75 -2.74 0.1157 0.0266 0.1369 0.1423 -3.79 0.1107 80.86 -4.32 PR_3_A1910 PR_3_A1910 11800.00 10760.00 9.67 2.2991 0.3909 2.8391 2.6900 5.54 2.2923 80.74 -0.30 PR_3_B2030 PR_3_B2030 10800.00 11404.80 -5.30 2.2997 0.5515 2.6533 2.8512 -6.94 2.2744 85.72 -1.10 PR_3_C6666 PR_3_C6666 8136.00 7554.75 7.69 2.6986 0.3233 3.2374 3.0219 7.13 2.9104 89.90 7.85 

97-2 PR_1_A3814 PR_1_A3814 251.50 255.20 -1.45 0.0575 0.0063 0.0619 0.0638 -2.98 --- --- --- 

PR_1_B3942 PR_1_B3942 253.10 267.20 -5.28 0.0574 0.0094 0.0629 0.0668 -5.84 --- --- --- PR_1_C4070 PR_1_C4070 173.70 185.25 -6.23 0.0577 0.0164 0.0688 0.0741 -7.15 0.0568 82.60 -1.51 PR_2_A3814 PR_2_A3814 472.80 504.80 -6.34 0.1175 0.0087 0.1121 0.1262 -11.17 0.1028 91.70 -12.51 PR_2_B3942 PR_2_B3942 512.90 529.20 -3.08 0.1160 0.0163 0.1270 0.1323 -4.01 --- 0.00 --- PR_2_C4070 PR_2_C4070 321.00 357.75 -10.27 0.1162 0.0269 0.1269 0.1431 -11.32 --- 0.00 --- PR_3_A3814 No ID Number 10900.00 10758.40 1.32 2.2985 0.3910 2.6643 2.6896 -0.94 2.2806 85.60 -0.78 PR_3_B3942 PR_3_B3942 12000.00 11412.40 5.15 2.3003 0.5520 2.7901 2.8531 -2.21 2.2544 80.80 -2.00 PR_3_C4070 PR_3_C4070 7000.00 6557.00 6.76 2.2996 0.3240 2.7752 2.6228 5.81 --- 0.00 --- 

98-1 PR_1_A7727 PR_1_A7727 180.50 188.57 -4.28 0.0595 0.0065 0.0626 0.0660 -5.15 --- --- --- 

PR_1_B7846 PR_1_B7846 157.80 175.25 -9.96 0.0594 0.0107 0.0626 0.0701 -10.70 --- --- --- PR_1_C7983 PR_1_C7983 247.10 253.67 -2.59 0.0594 0.0167 0.0735 0.0761 -3.42 --- --- --- PR_1_D0229 PR_1_D0229 187.40 195.71 -4.25 0.0582 0.0103 0.0652 0.0685 -4.82 --- --- --- PR_1_E1060 PR_1_E1060 232.50 242.67 -4.19 0.0581 0.0147 0.0691 0.0728 -5.08 --- --- --- PR_2_A5218 PR_2_A5218 339.70 357.43 -4.96 0.1164 0.0087 0.1182 0.1251 -5.52 --- --- --- PR_2_B5155 PR_2_B5155 304.90 328.00 -7.04 0.1154 0.0158 0.1209 0.1312 -7.85 --- --- --- PR_2_C5074 PR_2_C5074 456.30 473.00 -3.53 0.1155 0.0264 0.1357 0.1419 -4.37 --- --- --- PR_2_D0229 PR_2_D0229 368.70 377.43 -2.31 0.1163 0.0158 0.1280 0.1321 -3.10 --- --- --- PR_2_E1060 PR_2_E1060 473.00 473.67 -0.14 0.1146 0.0275 0.1406 0.1421 -1.06 --- --- --- PR_3_A5527 PR_3_A5527 8200.00 7696.57 6.54 2.3023 0.3915 2.8632 2.6938 6.29 --- --- --- PR_3_B7746 PR_3_B7746 6720.00 8126.75 -17.31 2.6990 0.5517 2.6707 3.2507 -17.84 --- --- --- PR_3_C7883 PR_3_C7883 10000.00 10081.00 -0.80 2.7009 0.3234 2.9935 3.0243 -1.02 --- --- --- PR_3_D0229 PR_3_D0229 7986.00 8148.00 -1.99 2.3001 0.5517 2.8023 2.8518 -1.74 --- --- --- PR_3_E8460 PR_3_E8460 15900.00 10088.67 57.60 2.7021 0.3245 4.7847 3.0266 58.09 --- --- --- 

Median -2.45 -3.82 -4.32 25th percentile -5.30 -8.07 -9.78 75th percentile 6.19 -1.40 -0.75 F-pseudosigmaInterquartile range

8.52 4.94 6.70 

11.49 6.67 9.04 
28 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1Comments: Good (G), marginal (M), and poor (P), refers to the condition of the sample upon arrival to the laboratory.

Table 27. Summary results for Sediment Laboratory Quality-Assurance studies in the Vancouver, Washington, laboratory[mg/L, milligrams per liter; g, grams; <, less than; >, greater than; ---, no data; N/A, not applicable]

Study

number

Actual

vial

shipping-ID

Reported

vial

number

Reported

sediment

concentration

(mg/L)

Actual

sediment

concentration

(mg/L)

Suspendedsediment

concentration

percent

difference

Actual

mass

of

fines

(g)

Actual

mass

of

sand

(g)

Reported

sediment

mass

(g)

Actual

sediment

mass

(g)

Sediment

mass

percent

difference

Reported

fines

net

mass

(g)

Reported

Percentage

<0.062

Fine-san

materia

mass

percen

differen

96-1 A1889293 WA A1889293 140.00 N/A N/A 0.0490 0.0050 0.0513 0.0540 -5.00 0.0446 87.00 -8.9

B1889693 WA B1889693 159.00 N/A N/A 0.0500 0.0079 0.0556 0.0579 -3.97 0.0467 84.00 -6.5C18810093 WA C18810093 147.00 N/A N/A 0.0490 0.0100 0.0587 0.0490 19.80 0.0475 81.00 -2.9A1749693 WA A1749693 599.00 N/A N/A 0.1980 0.0217 0.2088 0.2197 -4.96 0.1837 88.00 -7.2B17414293 WA B17414293 630.00 N/A N/A 0.2030 0.0297 0.2212 0.2327 -4.94 0.1880 85.00 -7.3C17416993 WA C17416993 606.00 N/A N/A 0.1980 0.0407 0.2106 0.2387 -11.77 0.1664 79.00 -15.9A1941393 WA A1941393 7366.00 N/A N/A 2.1950 0.4392 2.5625 2.6342 -2.72 2.0756 81.00 -5.4B1953793 WA B1953793 8726.00 N/A N/A 2.7000 0.4049 3.0368 3.1049 -2.19 2.5509 84.00 -5.5C1957093 WA C1957093 8108.00 N/A N/A 2.6800 0.2678 2.8285 2.9478 -4.05 2.5174 89.00 -6.0

96-2 A1905893 WA A1905893 449.00 464.96 -3.43 0.1010 0.0152 0.1092 0.1162 -6.06 --- --- --- 

B1908393 WA B1908393 427.00 441.48 -3.28 0.1000 0.0104 0.1022 0.1104 -7.40 --- --- --- C19012093 WA C19012093 275.00 293.95 -6.45 0.0980 0.0196 0.1085 0.1176 -7.72 --- --- --- A19319393 WA A19319393 1339.00 1365.72 -1.96 0.2970 0.0444 0.3268 0.3414 -4.28 --- --- --- B1939393 WA B1939393 1275.00 1315.60 -3.09 0.2990 0.0299 0.3111 0.3289 -5.41 --- --- --- C19317093 WA C19317093 1455.00 916.18 58.81 0.3010 0.0655 0.5719 0.3665 56.06 --- --- --- A1942693 WA A1942693 9626.00 9596.52 0.31 2.1810 0.2181 2.3433 2.3991 -2.33 --- --- --- B195493 WA B195493 12474.00 12387.92 0.69 2.6930 0.4040 3.0412 3.0970 -1.80 --- --- --- C1955993 WA C1955993 7993.00 8041.45 -0.60 2.6800 0.5366 3.1566 3.2166 -1.86 --- --- --- 

97-1 WA_1_A3111 WA_1_A3111 252.00 250.80 0.48 0.0567 0.0060 0.0620 0.0627 -1.12 0.0539 87.00 -4.8

WA_1_B3229 WA_1_B3229 269.00 272.40 -1.25 0.0582 0.0099 0.0670 0.0681 -1.62 0.0563 84.00 -3.3WA_1_C3367 WA_1_C3367 186.00 184.25 0.95 0.0582 0.0155 0.0730 0.0737 -0.95 0.0548 75.00 -5.9WA_2_A3111 WA_2_A3111 501.00 507.20 -1.22 0.1172 0.0096 0.1230 0.1268 -3.00 0.1119 91.00 -4.5WA_2_B3229 WA_2_B3229 462.00 929.60 -50.30 0.1159 0.1165 0.1130 0.2324 -51.38 0.1096 97.00 -5.4WA_2_C3367 WA_2_C3367 328.00 357.00 -8.12 0.1162 0.0266 0.1300 0.1428 -8.96 0.1014 78.00 -12.7WA_3_A2111 WA_3_A2111 10766.00 10761.20 0.04 2.2998 0.3905 2.6660 2.6903 -0.90 2.2661 85.00 -1.4WA_3_B2229 WA_3_B2229 11514.00 11403.20 0.97 2.2992 0.5516 2.8260 2.8508 -0.87 2.2608 80.00 -1.6WA_3_C6767 WA_3_C6767 7581.00 7561.00 0.26 2.7013 0.3231 3.0040 3.0244 -0.67 2.6736 89.00 -1.0

97-2 WA_1_A4115 WA_1_A4115 288.00 256.80 12.15 0.0575 0.0067 0.0710 0.0642 10.59 0.0653 92.00 13.6

WA_1_B4243 WA_1_B4243 263.00 274.40 -4.15 0.0577 0.0109 0.0650 0.0686 -5.25 0.0553 85.00 -4.2WA_1_C4371 WA_1_C4371 181.00 184.75 -2.03 0.0577 0.0162 0.0720 0.0739 -2.57 0.0547 76.00 -5.1WA_2_A4115 WA_2_A4115 458.00 501.60 -8.69 0.1163 0.0091 0.1130 0.1254 -9.89 0.1040 92.00 -10.6WA_2_B4243 WA_2_B4243 519.00 529.60 -2.00 0.1159 0.0165 0.1280 0.1324 -3.32 0.1114 87.00 -3.9WA_2_C4371 WA_2_C4371 355.00 358.50 -0.98 0.1153 0.0281 0.1410 0.1434 -1.67 0.1128 80.00 -2.1WA_3_A4115 WA_3_A4115 10696.00 10767.20 -0.72 2.3010 0.3910 2.6530 2.6918 -1.44 2.2551 85.00 -2.0WA_3_B4243 WA_3_B4243 11317.00 11412.80 -0.84 2.3004 0.5520 2.8150 2.8532 -1.34 2.2520 80.00 -2.1WA_3_C4371 WA_3_C4371 6460.00 6558.50 -1.50 2.2997 0.3240 2.5660 2.6234 -2.19 2.2581 88.00 -1.8

98-1 WA_1_A8028 WA_1_A8028 178.00 187.71 -5.18 0.0586 0.0071 0.0615 0.0657 -6.39 0.0547 89.00 -6.6

WA_1_B8145 WA_1_B8145 153.00 167.00 -8.38 0.0565 0.0103 0.0607 0.0668 -9.13 0.0510 84.00 -9.7WA_1_C8284 WA_1_C8284 232.00 246.00 -5.69 0.0579 0.0159 0.0690 0.0738 -6.50 0.0524 76.00 -9.4WA_2_A4917 NY_2_A5820 329.00 361.71 -9.04 0.1172 0.0094 0.1142 0.1266 -9.79 0.1039 91.00 -11.3WA_2_B4856 NY_2_B5753 314.00 332.75 -5.63 0.1165 0.0166 0.1247 0.1331 -6.31 0.1097 88.00 -5.8WA_2_C4773 NY_2_C5676 432.00 480.67 -10.12 0.1175 0.0267 0.1286 0.1442 -10.82 0.1016 79.00 -13.5WA_3_A5628 WA_3_A5628 7087.00 7684.57 -7.78 2.2986 0.3910 2.4567 2.6896 -8.66 2.0636 84.00 -10.2WA_3_B7945 WA_3_B7945 7569.00 8140.75 -7.02 2.7041 0.5522 3.0095 3.2563 -7.58 2.4678 82.00 -8.7WA_3_C8084 WA_3_C8084 9566.00 10075.67 -5.06 2.6996 0.3231 2.8358 3.0227 -6.18 2.5239 89.00 -6.5

Median -2.02 -4.05 -5.625th percentile -5.88 -6.50 -8.775th percentile -0.44 -1.67 -3.2F-pseudosigmaInterquartile range

4.03 3.58 4.15.44 4.83 5.5
ANALYSIS AND INTERPRETATION OF PROJECT DATA 29

Comparison of the 1996-98 Sediment

Laboratory Quality-Assurance Results with

the Results from Pilot Studies in Previous

Years

Sediment interlaboratory comparison studies were

made on a pilot basis in 1992 and 1994. Twenty sediment laboratories were providing data for the USGS in

1992; in 1994 the number had decreased to 18 sediment laboratories. Only 11 laboratories were providing

data for the USGS in 1996 and 12 laboratories were

providing data for the USGS in 1997-98. The differences associated with sand/fine separations and suspended-sediment concentrations were not tabulated in

the 1992 and 1994 pilot studies. Also the samples used

in the 1992 and 1994 pilot studies do not compare

directly to each other or with the samples used in study

numbers 96-1 through 98-1. A comparison of the sediment mass percent difference results from the 1992

and 1994 pilot (tables 28 and 29) indicates that the

results from the pilot studies were similar to the results

for samples with approximately the same amount of

sediment mass analyzed for the SLQA project

between 1996 and 1998 shown in tables 11-15.

In 1992, the median percent difference for sediment mass was –7.91 percent for samples with a

known mass of 10 to 35 mg, -3.86 percent for samples

with a known mass of 149 to 170 mg, and -3.41 percent for samples with a known mass of 240 to 274 mg

(table 28).

One of the key findings of the 1992 pilot study

was that a systematic low bias of about 1percent

occurred due to material passing through the filter and

common processing steps (Schroder and others, 1996).

The follow-up pilot study completed in 1994 provided

further information on the filtration method that was

routinely used for concentration analyses, as well as a

preliminary examination of particle-size analyses

using the sieve-pipette method. The median percent

difference for sediment mass for the 1994 pilot study

for samples with a known mass of 49 to 51 mg was

–4.60; there was a -4.30 percent difference for samples

with a known mass of 90 to 102 mg, and -4.34 percent

for samples with a known mass of 197 to 203 mg

(table 29). There was an overall median percent difference between laboratories of –3.86 percent in 1992

and –5.00 percent in 1994.

Control Charts of the 1996-98 Sediment

Laboratory Quality-Assurance Results

Control charts of the percent difference for each

measurement made by the participating laboratories

are shown in figures 1 through 57. These control

charts, which were prepared according to sample base

mass and analysis type within each SLQA study, give

the percent difference for the reported sediment mass,

fine-size material mass, sand-size material mass, and

suspended-sediment concentration. The median difference for all laboratories for each analysis in each sample amount is clearly identified on the graphs. In a

traditional control chart, the upper and lower control

limits are typically set at + 3 standard deviations from

the mean. The median and F-pseudosigma were used

in place of the mean and standard deviation. The

median was used to define the central tendency. The

F-pseudosigma was used as a resistant measure of data

spread similar to the standard deviation.

The results for a given analysis were determined

to be out of statistical control when they exceeded

either the upper or lower control limit. Use of the

median rather than the mean and definition of the control limits that are based on the F-pseudosigma rather

than the standard deviation are appropriate because the

data are not normally distributed. Furthermore, the

data contained a large number of outliers—data values

that fell outside the range of +3 F-pseudosigma from

the median—that may have biased the mean and standard deviation.

If the median difference from all of the pooled

data reported by the laboratories were zero, the median

difference line for each control chart would also be

zero for each type of measurement. The fact that the

median difference is consistently offset from zero indicates that the data for each of the physical sediment

properties are biased. The negative bias for suspended-sediment concentration (figs. 46-57) may be

due to dissolution of a small amount of the fine-size

material mass that is lost during filtration unless the

filtrate is captured by using an evaporation dish. The

median bias, for the SLQA studies that were completed in 1996-98, is consistent with the median bias in

pilot studies using the AC spark-plug dust as a reference material. A significant part of this bias is attributable to common sample-processing steps and is

therefore difficult to avoid. Schroder and others (1996)

determined that about 1.3 percent of the known mass
30 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

1The confidence level for specific statistics returns the confidence interval for a population mean. The confidence interval is a range on either side of a sample mean

the null hypothesis when it is true. If we assume alpha equals 0.05 we need to calculate the area under the standard normal curve that equals (1 - alpha), or 95 percent. Th

sample mean +1.96 times the standard deviation divided by the square root of the number of data points.

1The confidence level for specific statistics returns the confidence interval for a population mean. The confidence interval is a range on either side of a sample mean

the null hypothesis when it is true. If we assume alpha equals 0.05 we need to calculate the area under the standard normal curve that equals (1 - alpha), or 95 percent. Th

sample mean +1.96 times the standard deviation divided by the square root of the number of data points.

Table 28. 1992 pilot study sediment mass percent difference

10 to 35 milligram samples 149 to 170 milligram samples 

Mean -5.24 Mean -4.12 Mean Standard error 4.60 Standard error 0.89 Standard error Median -7.91 Median -3.86 Median 25th percentile -15.75 25th percentile -5.09 25th percentile 75th percentile -1.42 75th percentile -2.81 75th percentile F-pseudosigma 10.63 F-pseudosigma 1.69 F-pseudosigmStandard deviation 20.59 Standard deviation 3.88 Standard deviaSample variance 423.77 Sample variance 15.09 Sample varianKurtosis 9.23 Kurtosis 5.06 Kurtosis Skewness 2.63 Skewness -0.90 Skewness Range 94.39 Range 20.59 Range Minimum -25.00 Minimum -15.69 Minimum Maximum 69.39 Maximum 4.90 Maximum Count 20.00 Count 20.00 Count Confidence level (95.0 percent)1 9.63 Confidence level (95.0 percent)1 1.87 Confidence lev

Table 29. 1994 pilot study sediment mass percent difference

49 to 51 milligram samples 90 to 102 milligram samples 

Mean -4.75 Mean -4.12 Mean Standard error 0.54 Standard error 0.46 Standard error Median -4.60 Median -4.30 Median 25th percentile -6.49 25th percentile -5.88 25th percentile 75th percentile -2.42 75th percentile -2.58 75th percentile F-pseudosigma 3.01 F-pseudosigma 2.45 F-pseudosigmStandard deviation 3.72 Standard deviation 3.19 Standard deviaSample variance 13.80 Sample variance 10.19 Sample varianKurtosis 0.38 Kurtosis 5.88 Kurtosis Skewness -0.30 Skewness -0.63 Skewness Range 16.18 Range 22.52 Range Minimum -13.53 Minimum -16.96 Minimum Maximum 2.65 Maximum 5.56 Maximum Count 48.00 Count 48.00 Count Confidence level (95.0 percent)1 1.08 Confidence level (95.0 percent)1 0.93 Confidence lev
ANALYSIS AND INTERPRETATION OF PROJECT DATA 31

in the sample vial is lost in the sample-transfer procedures that started with the removal of the sample from

the vial and ended with the material collected in the

filter. An additional 1 percent of the mass of the test

sample material passes through the filter (Whatman

No. 934-AH) and is lost unless the filtrate is analyzed

by using an evaporation dish (Schroder and others,

1996).

The positive bias observed for sand-size material

mass (figs. 31-45) and the negative bias observed for

fine-size material mass (figs. 16-30) may be due to a

small amount of fine-size material mass adhering to

the sand-size grains, which increases the sand-size

material mass and decreases the fine-size material

mass.

The median line on the sand-size graphs is the

measure of central tendency and this median line

divides the bottom 50 percent of the data from the top

50 percent of the data. For example, the median line

on the suspended-sediment concentration control

charts (figs. 46-57) ranges from –4.86 to –2.45 percent

for the group of samples with the lowest suspended-sediment concentration and from –1.27 to

–0.36 percent for the group of samples with the highest suspended-sediment concentration.

The number of times each laboratory exceeded a

control limit for each of the four analyses: (1) sediment mass, (2) fine-size material mass, (3) sand-size

material mass, and (4) suspended-sediment concentration, are listed in tables 30-34. Tables 30-34 also give

the percentage of reported values for a given laboratory that exceeded the + 3 F-pseudosigma from the

median control limits for each study. This is an important statistic to consider when evaluating the number

of values that exceed the control limits because participation rates among laboratories varied considerably;

for example, some laboratories did not perform

sand/fine separations, one laboratory performed only

suspended-sediment concentration analyses, and some

analyses were not completed due to leakage of the

sample during transportation.

The ability of a laboratory to produce data consistently within statistical control in the SLQA studies

may be a useful indication of its ability to produce

environmental data consistently within statistical control. Scrutiny of tables 30 through 34 reveals that there

were several laboratories with high rates of participation in the SLQA studies that rarely exceeded the control limits for the various physical sediment properties.

Laboratories with high rates of participation were

those laboratories that completed all analyses. These

laboratories usually had no, or very few, control limit

exceedances in a particular SLQA study and may have

been producing the most accurate environmental data

during the time of that study. Some of the laboratories

consistently had no, or very few, control limit exceedances in all of SLQA studies completed during

1996-98. The environmental data produced by such

laboratories during 1996-98 may be of a higher level

of precision than the environmental data from laboratories that did not consistently produce SLQA data

within statistical control.

Analyses from samples that were reported as having leaked during transit were not considered, resulting in a smaller number of data values for laboratories

reporting a large number of samples leaking during

transit. The number of samples that leaked in transit

for each laboratory for the five SLQA studies completed from August 1996 through June 1998 are

shown in figure 58 (at the back of the report).

Scatter plots of suspended-sediment-concentration percent difference for each laboratory over time

are shown in figures 59-94 at the back of the report.

Figures 59-94 are broken down according to sample

amount, resulting in three graphs for each of the 12

laboratories in studies 96-1 through 98-1, and are

intended to show graphically any changes in laboratory performance between August 1996 and June

1998 with regard to suspended-sediment-concentration data. For example, among the 5 studies, some of

the laboratories that performed the worst in study

number 96-1 had the best overall performance in study

number 98-1.
32 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98 EXPLANATION Reported values exceeded the control limit for: M Sediment mass percent difference F Fine-size material mass percent difference S Sand-size material mass percent difference C Suspended-sediment concentration percent difference

1Samples noted as arriving in poor or marginal

condition were excluded from the analysis.

2This is a contract laboratory.

Table 30. Control limit exceedances (+3 F-pseudosigma) for the Sediment Laboratory Quality-Assurance project, study numbe[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3fine-size material; sand-size material was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Participating

laboratory

Sample class 1 Sample class 2 Sample class 3 Total number

exceeded1

Total number

analyzed1

California 0 27 Hawaii 0 4 Iowa 0 27 Kentucky S 1 27 Louisiana 0 27 Missouri S 1 27 Montana 0 27 New Mexico S S,S 3 27 Ohio2 M 1 9 

Puerto Rico M,F,F F,S 5 27 Washington M 1 27 
ANALYSIS AND INTERPRETATION OF PROJECT DATA 33 EXPLANATION Reported values exceeded the control limit for: M Sediment mass percent difference F Fine-size material mass percent difference S Sand-size material mass percent difference C Suspended-sediment concentration percent difference

1Samples noted as arriving in poor or marginal

condition were excluded from the analysis.

2This is a contract laboratory.

Table 31. Control limit exceedances (+3 F-pseudosigma) for the Sediment Laboratory Quality-Assurance project, study numbe[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3fine-size material; sand-size material was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Participating

laboratory

Sample class 1 Sample class 2 Sample class 3 Total number

exceeded1

Total number

analyzed1

California 0 25 Hawaii C 1 15 Iowa 0 18 Kentucky 0 24 Louisiana 0 36 Missouri 0 12 Montana 0 32 New Mexico S S F,F,C 5 36 Ohio2 0 18 

Puerto Rico 0 36 Washington M,C 2 18 
34 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98 EXPLANATION Reported values exceeded the control limit for: M Sediment mass percent difference F Fine-size material mass percent difference S Sand-size material mass percent difference C Suspended-sediment concentration percent difference

1Samples noted as arriving in poor or marginal

condition were excluded from the analysis.

2This is a contract laboratory.

Table 32. Control limit exceedances (+3 F-pseudosigma) for the Sediment Laboratory Quality-Assurance project, study number [Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,2fine-size material; sand-size material was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Participating

laboratory

Sample class 1 Sample class 2 Sample class 3 Total number

exceeded1

Total number

analyzed1

California 0 36 Hawaii 0 18 Iowa M 1 36 Kentucky S 1 36 Louisiana 0 36 Missouri 0 22 Montana 0 34 New Mexico 0 36 New York2 C,C,C C,C,C C,C 8 8 Ohio2 0 18 

Puerto Rico M,F M,F 4 36 Washington 0 27 
ANALYSIS AND INTERPRETATION OF PROJECT DATA 35 EXPLANATION Reported values exceeded the control limit for: M Sediment mass percent difference F Fine-size material mass percent difference S Sand-size material mass percent difference C Suspended-sediment concentration percent difference

1Samples noted as arriving in poor or marginal

condition were excluded from the analysis.

2This is a contract laboratory.

Table 33. Control limit exceedances (+3 F-pseudosigma) for the Sediment Laboratory Quality-Assurance project, study number 9[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,2fine-size material; sand-size material was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Participating

laboratory

Sample class 1 Sample class 2 Sample class 3 Total number

exceeded1

Total number

analyzed1

California S 1 36 Hawaii M M,M,C,C 5 18 Iowa 0 36 Kentucky 0 36 Louisiana 0 36 Missouri M,S,S,S,C S,S,S 8 36 Montana 0 36 New Mexico S,C S F,S 5 32 New York2 C,C C 3 9 

Ohio2 0 18 

Puerto Rico S 1 26 Washington M,F,C 3 27 
36 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98 EXPLANATION Reported values exceeded the control limit for: M Sediment mass percent difference F Fine-size material mass percent difference S Sand-size material mass percent difference C Suspended-sediment concentration percent difference

1Samples noted as arriving in poor or marginal

condition were excluded from the analysis.

2This is a contract laboratory.

Table 34. Control limit exceedances (+3 F-pseudosigma) for the Sediment Laboratory Quality-Assurance project, study number 9[Sample class 1, 50 to 100 milligrams of fine-size material; sample class 2, 101 to 300 milligrams of fine-size material; sample class 3, 2,200 to 3,2fine-size material; sand-size material was added in an amount ranging from 9 to 28 percent of the mass of fine-size material in each sample class]

Participating

laboratory

Sample class 1 Sample class 2 Sample class 3 Total number

exceeded1

Total number

analyzed1

California 0 36 Hawaii M,M 2 18 Iowa 0 36 Kentucky 0 36 Louisiana S M,F,S,S 5 36 Missouri S,S S 3 36 Montana 0 36 New Mexico M,F,F,S,S,C F,S,S S,S,S 12 36 New York2 C,C,C,C C,C,C 7 18 

Ohio2 M 1 18 

Puerto Rico M,C 2 30 Washington M,M,F 3 36 
RECENTLY IMPLEMENTED AND PROPOSED PLANS 37

The upper quartile, median, and lower quartile of

the differences in percent between the reported and

known values for three key sediment properties: suspended-sediment concentration, fine-size material

mass, and sand-size material mass are shown in figure

95 at the back of the report; it is a graphical representation of the overall results for each laboratory. The

difference between the upper and lower quartiles is the

interquartile range for each laboratory. The interquartile range is a useful indicator of the variability associated with the measurements produced by a given

laboratory. The median differences between the

reported and known values can be used as an indication of laboratory bias (taking into account the previously discussed limitations—leakage, for

example—of the samples used in the study). Although

there was variability in the reported results, it is important to note that any changes in laboratory performance over time are not detectable in figure 95 where

the results for all of the SLQA studies are pooled. It is

also important to note that some laboratories with the

greatest amount of variability in their results on an

overall basis have been steadily improving in recent

SLQA studies and have in fact produced some of the

best results of any of the laboratories in recent interlaboratory comparison studies.

Results shown in figure 95 indicate there were

some substantial differences among the 12 laboratories

that participated in the five SLQA studies that were

made from August 1996 to June 1998. All the participating laboratories performed suspended-sediment

concentration analyses (fig. 95A), but only 9 of the 12

laboratories performed sand/fine separations (fig. 95B

and 95C). The overall median percent difference for

suspended-sediment concentration on an individual

laboratory basis ranged from –18.04 to –0.33 for the

12 laboratories. Five of the 12 laboratories had an

overall median percent difference for suspended-sediment concentration of –2.02 to –0.33 percent. There

was less variability in the median difference for the

measured fine-size material mass than for sand-size

material mass (figs. 95B and 95C). The overall median

percent difference for fine-size material mass varied

from –10.11 to –4.27 percent. Except for one laboratory, the median percent difference for fine-size material mass was within a fairly narrow range of –6.76 to

–4.27 percent (fig. 95B). The median percent difference for sand-size material mass differed among laboratories more than any other physical sediment

property measured in the study. The overall median

percent difference for the sand-size material mass

ranged from –1.49 to 26.39 percent (fig. 95C). Five of

the 9 laboratories that do sand/fine separations had

overall median percent differences for sand-size material mass of –1.49 to 2.98 percent.

RECENTLY IMPLEMENTED AND

PROPOSED PLANS

A double-blind reference sample project for physical sediment properties began in August 1999. The

project provides the capability for submitting environmental water-sediment samples and quality-control

samples that are disguised as environmental samples

to participating laboratories (U.S. Geological Survey,

Office of Surface Water Technical Memorandum No.

98.05, 1998). Also in 1999, participation of several

additional non-USGS laboratories in the single-blind

reference sample project for physical sediment properties began. The participation of sediment laboratories

associated with other Federal agencies and laboratories in Canada facilitates transboundary sediment studies throughout North America. By participating in the

single-blind reference sample project, these laboratories will provide an additional benchmark for assessing the performance of USGS laboratories. Another

area of project expansion, which began in 1999,

focuses on follow-up evaluations for laboratories that

are shown to have substantial deficiencies during

onsite reviews or that provide data in the SLQA studies that lie outside statistically determined data-quality

boundaries (U.S. Geological Survey, Office of Surface

Water Technical Memorandum No. 98.05, 1998).

Finally, an ongoing, in-depth monitoring and evaluation effort of particle-size analyses, which includes

particle-size analyses to be completed by sieve/pipette,

Sedigraph, and bottom-withdrawal methods, is

expected to begin in 2000.
38 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

SUMMARY

When evaluating the data in this report, the reader

should keep in mind that every measurement has an

error component associated with it. This is true for

every type of data collected. Quantifying and understanding the error component are the keys to knowing

the capabilities and limitations of a database. There are

certain limits and constraints on every method used to

collect data, and no one, no matter how careful or conscientious, can perform at a level beyond the limits of

the method. The reader should also keep in mind that

some sources of measurement errors are beyond the

laboratory’s control. Given that the Sediment Laboratory Quality-Assurance project is relatively new, it is

too soon to evaluate the question of method constraints relative to correctable sources of error. It is

also premature to use the data from these first few

Sediment Laboratory Quality-Assurance studies to

judge the performance of any of the participating laboratories. There were also some notable differences in

the results for the 12 laboratories that participated in

the five Sediment Laboratory Quality-Assurance studies conducted from August 1996 through June 1998.

For example, the overall median percent difference for

suspended-sediment concentration on an individual

laboratory basis ranged from –18.04 to –0.33 for the

12 laboratories. Five of the 12 laboratories had an

overall median percent difference for suspended-sediment concentration of –2.02 to –0.33 percent. There

was less variability in the median percent difference

for the measured fine-size material mass. The overall

median percent difference for fine-size material mass

varied from –10.11 to –4.27 percent. Except for one

laboratory, the median percent difference for fine-size

material mass was within a fairly narrow range of

–6.76 to –4.27 percent. The median percent difference

for sand-size material mass differed among laboratories more than any other physical sediment property

measured in the study. The overall median percent difference for sand-size material mass ranged from –1.49

to 26.39 percent. Five of the nine laboratories that do

sand/fine separations had overall median percent differences for sand-size material mass that ranged from

–1.49 to 2.98 percent.

Careful review of the control charts reveals that

certain laboratories consistently produced data within

statistical control for some or all of the physical sediment properties measured in this study, but other laboratories occasionally produced data exceeding the

control. The tables that summarize the incidence of

control-limit exceedance and indicate there were several laboratories with high rates of participation in the

Sediment Laboratory Quality-Assurance studies that

had very rarely exceeded the control limits for the various physical sediment properties.

REFERENCES

Choi, W.W., and Chen, K.Y., 1976, Associations of chlorinated hydrocarbons with fine particles and humic substances in nearshore superficial sediments:

Environmental Science Technology, v. 10, no. 8, p.

782-786.

Edwards, T.K., and Glysson, G.D., 1986, Field methods for

measurement of fluvial sediment: U.S. Geological Survey Techniques of Water-Resources Investigations,

book 3, chap. C2, p. 59.

Fairchild, J.F., 1987, Effects of sediment and contaminated

sediments on stream ecosystems: Water, Air, and Soil

Pollution, v. 36, p. 271-293.

Glysson, G.D., 1989, 100 Years of Sedimentation Study by

the USGS, in Sediment Transport Modeling: Proceeding of the International Symposium, American Society

of Civil Engineers, August 14-18, 1989, New Orleans,

Louisiana, p. 827-829.

Guy, H.P., 1969, Laboratory theory and methods for sediment analysis: U.S. Geological Survey Techniques of

Water-Resources Investigations, book 5, chap. C1, p.

58.

Johnston, P.R., and Swanson, R., 1981, A correlation

between the results of different instruments used to

determine the particle-size distribution in AC fine test

dust: Powder Technology, v. 32, p. 119-124.

Knott, J.C., Sholar, C.J., and Matthes, W.J., 1992, Quality

assurance guidelines for the analysis of sediment concentration by U.S. Geological Survey sediment laboratories: U.S. Geological Survey Open-File Report 92-33,

22 p.

Matthes, W.J., Sholar, C.J., and George, J.R., 1991, Quality-assurance plan for analysis of fluvial sediment: U.S.

Geological Survey Open-File Report 91-467, 28 p.
REFERENCES 39

Schroder, L.J., Shupp, D.W., Gilroy, E.J., and Long, H.K.,

1996, A method for evaluating sediment laboratories:

Proceedings of the sixth federal interagency sedimentation conference, Las Vegas, Nevada, March 10-14,

1996, v. 2, p. 26-31.

U.S. Geological Survey, 1991, Training – Certification

Training for Sediment Laboratories: U.S. Geological

Survey, Office of Surface Water Technical Memorandum No. 91.11, issued August 14, 1991, at URL

http://water.usgs.gov/admin/memo/SW/sw91.11.txt

U.S. Geological Survey, 1996, Initiation of a Sediment Laboratory Quality Assurance project: U.S. Geological

Survey, Office of Surface Water Technical Memorandum No. 96.11, issued August 28, 1996, at URL

http://water.usgs.gov/admin/memo/SW/sw96.11.txt

U.S. Geological Survey, 1998, A national quality assurance

project for sediment laboratories operated or used by

the Water Resource Division: U.S. Geological Survey,

Office of Surface Water Technical Memorandum No.

98.05, issued March 2, 1998, at URL

http://water.usgs.gov/admin/memo/SW/sw98.05.txt
40 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 1. Sediment-mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_1_A180993

CA_1_B1802693

CA_1_C1884693

HI_1_A1884293 *

HI_1_B1885593 *

HI_1_C1886393 * IA_1_A18811893

IA_1_B18815893

IA_1_C18815893

KY_1_A18817793

KY_1_B18818793

KY_1_C18819793

LA_1_A18816493

LA_1_B18817693

LA_1_C18812693

MO_1_A18811393

MO_1_B18812393

MO_1_C18816693

MT_1_A18813393

MT_1_B18813693

MT_1_C18814493

NM_1_A18811493

NM_1_B18812293

NM_1_C18819493

OH_1_A18814793

OH_1_B18817493

OH_1_C18819093

PR_1_A18812493

PR_1_B18818293

PR_1_C18819393

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available
REFERENCES 41

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 2. Sediment-mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_1_A1902393

CA_1_B1903493

CA_1_C19011493

HI_1_A1905593

HI_1_B19013893

HI_1_C19019893

IA_1_A1903793

IA_1_B19010093

IA_1_C19017493

KY_1_A190493

KY_1_B1901393

KY_1_C1906993

LA_1_A1901293

LA_1_B19010693

LA_1_C19017393

MO_1_A1904293

* MO_1_B1908093 * MO_1_C19010293

MT_1_A1904993

MT_1_B19018793

* MT_1_C19012793

NM_1_A190893

NM_1_B19011893

NM_1_C19015393

OH_1_A1907193

OH_1_B19015893

OH_1_C19019693

PR_1_A190293

PR_1_B1901193

PR_1_C1902893

WA1A1905893

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
42 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 3. Sediment-mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_1_A0101

CA_1_B0238

CA_1_C0357

HI_1_A0402

HI_1_B0538

HI_1_C0658

IA_1_A0703

IA_1_B0837

IA_1_C0959

KY_1_A1004

KY_1_B1136

KY_1_C1260

LA_1_A1305

LA_1_B1435

LA_1_C1561

MO_1_A1106

MO_1_B1234

MO_1_C6262

MT_1_A1907

MT_1_B2033

MT_1_C2163

NM_1_A2208

NM_1_B2332

NM_1_C2464

NY_1_A3412 *

NY_1_B3528 *

NY_1_C3668 *

OH_1_A2509

OH_1_B2631

OH_1_C2765

PR_1_A2810

PR_1_B2930

PR_1_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 43

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 4. Sediment-mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_1_A115

CA_1_B1233

CA_1_C1361

HI_1_A146

HI_1_B1534 (-84.62)

HI_1_C1662

IA_1_A177

IA_1_B1835

IA_1_C1963

KY_1_A208

KY_1_B2136

KY_1_C2264

LA_1_A239

LA_1_B2437

LA_1_C2565

MO_1_A2610

MO_1_B2738

MO_1_C2866

MT_1_A2911

MT_1_B3039

MT_1_C3167

NM_1_A3212

NM_1_B3340

NM_1_C3468

NY_1_A4416

*

NY_1_B4544

*

NY_1_C4672

*

OH_1_A3513

OH_1_B3641

OH_1_C3769

PR_1_A3814

PR_1_B3942

PR_1_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
44 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 5. Sediment-mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_1_A4717

CA_1_B4856

CA_1_C4973

HI_1_A5018

HI_1_B5155

HI_1_C5274

IA_1_A5319

IA_1_B5454

IA_1_C5575

KY_1_A5620

KY_1_B5753

KY_1_C5876

LA_1_A5921

LA_1_B6052

LA_1_C6177

MO_1_A6222

MO_1_B6351

MO_1_C6478

MT_1_A6523

MT_1_B6650

MT_1_C6779

NM_1_A6824

NM_1_B6949

NM_1_C7080

NY_1_A7125 *

NY_1_A7125 *

NY_1_B7248 *

NY_1_B7248 *

NY_1_C7281 *

NY_1_C7281 *

OH_1_A7426

OH_1_B7547

OH_1_C7682

PR_1_A7727

PR_1_B7846

PR_1_C7983

PR_1_D0229

PR1E1060

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 45

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 6. Sediment-mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_2_A1748293

CA_2_B17412393

CA_2_C17416693

HI_2_A1746293

* HI_2_B17415893

HI_2_C17417693

IA_2_A17413693

IA_2_B17416893

IA_2_C17417393

KY_2_A1741693

KY_2_B17412693

KY_2_C17418893

LA_2_A17413393

LA_2_B17415393

LA_2_C17415993

MO_2_A1749393

MO_2_B17412293

MO_2_C17414893

MT_2_A1742493

MT_2_B1744993

MT_2_C17413293

NM_2_A1745293

NM_2_B1749893

NM_2_C17418393

OH_2_A1749593

OH_2_B17416293

OH_2_C17417893

PR_2_A1746393

PR_2_B17414593

PR_2_C17414693

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available
46 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 7. Sediment-mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_2_A193293

CA_2_B1933493

CA_2_C1934993

HI_2_A1936993

HI_2_B19315393

HI_2_C19318793

IA_2_A19310493

IA_2_B19312193

IA_2_C19314793

KY_2_A1933193

KY_2_B1934193

KY_2_C1939193

LA_2_A1931893

LA_2_B19310993

LA_2_C19317493

MO_2_A1938793 * MO_2_B19313493 * MO_2_C19317293

MT_2_A1934293

MT_2_B1938993

MT_2_C19312393

NM_2_A1933993

NM_2_B19311293

NM_2_C19316193

OH_2_A1931293

OH_2_B1935893

OH_2_C19319693

PR_2_A1934493

PR_2_B1933893

PR_2_C1935293

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
REFERENCES 47

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 8. Sediment-mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_2_A0101

CA_2_B0239

CA_2_C0357

HI_2_A0402

HI_2_B0538

HI_2_C0658

IA_2_A0703

IA_2_B0837

IA_2_C0959

KY_2_A1004

KY_2_B1136

KY_2_C1260

LA_2_A1305

LA_2_B1435

LA_2_C1561

MO_2_A1606

MO_2_B1734

MO_2_C1862

MT_2_A1907

MT_2_B2033

MT_2_C2163

NM_2_A2208

NM_2_B2332

NM_2_C2464

NY_2_A3412

*

NY_2_B3528

*

NY_2_C3668

*

OH_2_A2509

OH_2_B2631

OH_2_C2765

PR_2_A2810

PR_2_B2930

PR_2_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
48 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 9. Sediment-mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_2_A115

CA_2_B1233

CA_2_C1361

HI_2_A146

HI_2_B1534

HI_2_C1662

IA_2_A177

IA_2_B1835

IA_2_C1963

KY_2_A208

KY_2_B2136

KY_2_C2264

LA_2_A239

LA_2_B2437

LA_2_C2565

MO_2_A2610

MO_2_B2738

MO_2_C2866

MT_2_A2911

MT_2_B3039

MT_2_C3167

NM_2_A3212

NM_2_B3340

NM_2_C3468

NY_2_A4416 *

NY_2_B4544 *

NY_2_C4672 *

OH_2_A3513

OH_2_B3641

OH_2_C3769

PR_2_A3814

PR_2_B3942

PR_2_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 49

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 10. Sediment-mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_2_A8228

CA_2_B8145

CA_2_C8084

HI_2_A7927

HI_2_B7846

HI_2_C7783

IA_2_A7626

IA_2_B7547

IA_2_C7482

KY_2_A7325

KY_2_B7248

KY_2_C7181

LA_2_A7024

LA_2_B6949

LA_2_C6880

MO_2_A6723

MO_2_B6650

MO_2_C6579

MT_2_A6422

MT_2_B6351

MT_2_C6278

NM_2_A6121

NM_2_B6052

NM_2_C5977

NY_2_A5820

*

NY_2_A5820

*

NY_2_B5753

*

NY_2_B5753

*

NY_2_C5676

*

NY_2_C5676

*

OH_2_A5519

OH_2_B5454

OH_2_C5375

PR_2_A5218

PR_2_B5155

PR_2_C5074

PR_2_D0229

PR2E1060

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
50 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 11. Sediment-mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material fromstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_3_A1943393

CA_3_B1947893

CA_3_C195693

HI_3_A194393 *

HI_3_B1947493

HI_3_C1955093

IA_3_A1943293

IA_3_B1956093

IA_3_C1956393

KY_3_A1944493

KY_3_B1946393

KY_3_C1951493

LA_3_A1946093

LA_3_B195393

LA_3_C1956993

MO_3_A1945993

MO_3_B194793

MO_3_C1954193

MT_3_A1946993

MT_3_B1947993

MT_3_C1952493

NM_3_A194893

NM_3_B1948093

NM_3_C1957793

OH_3_A1942793 (-45.04)

OH_3_B194693

OH_3_C1955193

PR_3_A1944393

PR_3_B1944693

PR_3_C1955493

WA3A1941393

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available
REFERENCES 51

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 12. Sediment-mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material fromstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_3_A1947693

*

CA_3_B195993

*

CA_3_C1958093

HI_3_A1944293

*

HI_3_B1951893

*

HI_3_C1956793

*

IA_3_A1945393

IA_3_B1952793

IA_3_C1955793

KY_3_A1946493

KY_3_B1951693

KY_3_C1953193

LA_3_A1942293

LA_3_B195793

LA_3_C1956693

MO_3_A1942493

* MO_3_B1951293 * MO_3_C1954693

MT_3_ B1951993

MT_3_A1941493

MT_3_C1954793

NM_3_A1943693

NM_3_B1953993

NM_3_C1956593

OH_3_A1944893

OH_3_B1953293

OH_3_C1956493

PR_3_A1945293

PR_3_B1951393

PR_3_C1952393

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
52 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 13. Sediment-mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material fromstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_3_A0101

CA_3_B0239

CA_3_C5757

HI_3_A0302 *

HI_3_B0438 *

HI_3_C5858 *

IA_3_A0503

IA_3_B0637

IA_3_C5959

KY_3_A0704

KY_3_B0836

KY_3_C6060

LA_3_A0905

LA_3_B1035

LA_3_C6161

MO_3_A1106

MO_3_B1234

MO_3_C6262

MT_3_A1307

MT_3_B1433

MT_3_C6363

NM_3_A1508

NM_3_B1632

NM_3_C6464

NY_3_A2613 *

NY_3_B2726 *

NY_3_C6868 *

OH_3_A1709

OH_3_B1831

OH_3_C6565

PR_3_A1910

PR_3_B2030

PR_3_C6666

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 53

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 14. Sediment-mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material fromstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_3_A115

CA_3_B1233

CA_3_C1361

HI_3_A146

HI_3_B1534

HI_3_C1662

IA_3_A177

IA_3_B1835

IA_3_C1963

KY_3_A208

KY_3_B2136

KY_3_C2264

LA_3_A239

LA_3_B2437

LA_3_C2565

MO_3_A2610

MO_3_B2738

MO_3_C2866

MT_3_A2911

MT_3_B3039

MT_3_C3167

NM_3_A3212

*

NM_3_B3340

NM_3_C3468

NY_3_A4416

*

NY_3_B4544

*

NY_3_C4672

*

OH_3_A3513

OH_3_B3641

OH_3_C3769

PR_3_A3814

PR_3_B3942

PR_3_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
54 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 15. Sediment-mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material fromstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SEDIMENT-MASS PERCENT DIFFERENCE

CA_3_A0617

CA_3_B5756

CA_3_C5873

HI_3_A1018

HI_3_B5955

HI_3_C6074

IA_3_A4719

IA_3_B6154

IA_3_C6275

KY_3_A4820

KY_3_B6353

KY_3_C6476

LA_3_A4921

LA_3_B6552

LA_3_C6677

MO_3_A5022

MO_3_B6751

MO_3_C6878

MT_3_A5123

MT_3_B6950

MT_3_C7079

NM_3_A5224

NM_3_B7149

NM_3_C7280

NY_3_A5325 *

NY_3_A5325 *

NY_3_B7348 *

NY_3_B7348 *

NY_3_C7481 *

NY_3_C7481 *

OH_3_A5426

OH_3_B7547

OH_3_C7682

PR_3_A5527

PR_3_B7746

PR_3_C7883

PR_3_D0229

PR3E8460 (58.09)

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
REFERENCES 55

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 16. Fine-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A180993

CA_1_B1802693

CA_1_C1884693

HI_1_A1884293

*

HI_1_B1885593

*

HI_1_C1886393

* IA_1_A18811893

IA_1_B18815893

IA_1_C18815893

KY_1_A18817793

KY_1_B18818793

KY_1_C18819793

LA_1_A18816493

LA_1_B18817693

LA_1_C18812693

MO_1_A18811393

MO_1_B18812393

MO_1_C18816693

MT_1_A18813393

MT_1_B18813693

MT_1_C18814493

NM_1_A18811493

NM_1_B18812293

NM_1_C18819493

OH_1_A18814793

* OH_1_B18817493 * OH_1_C18819093 * PR_1_A18812493

PR_1_B18818293

PR_1_C18819393

WA1A1889293

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available
56 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 17. Fine-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A1902393

CA_1_B1903493

CA_1_C19011493

HI_1_A1905593 * HI_1_B19013893 * HI_1_C19019893 *

IA_1_A1903793 * IA_1_B19010093 * IA_1_C19017493 *

KY_1_A190493 *

KY_1_B1901393 *

KY_1_C1906993

LA_1_A1901293

LA_1_B19010693

LA_1_C19017393

MO_1_A1904293 * MO_1_B1908093 * MO_1_C19010293

MT_1_A1904993

MT_1_B19018793 * MT_1_C19012793

NM_1_A190893

NM_1_B19011893

NM_1_C19015393

OH_1_A1907193 * OH_1_B19015893 * OH_1_C19019693 *

PR_1_A190293

PR_1_B1901193

PR_1_C1902893

WA1A1905893 

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 57

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 18. Fine-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A0101

CA_1_B0238

CA_1_C0357

HI_1_A0402

*

HI_1_B0538

*

HI_1_C0658

*

IA_1_A0703

IA_1_B0837

IA_1_C0959

KY_1_A1004

KY_1_B1136

KY_1_C1260

LA_1_A1305

LA_1_B1435

LA_1_C1561

MO_1_A1106

*

MO_1_B1234

*

MO_1_C6262

MT_1_A1907

MT_1_B2033

MT_1_C2163

NM_1_A2208

NM_1_B2332

NM_1_C2464

NY_1_A3412

*

NY_1_B3528

*

NY_1_C3668

*

OH_1_A2509

*

OH_1_B2631

*

OH_1_C2765

*

PR_1_A2810

PR_1_B2930

PR_1_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
58 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 19. Fine-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A115

CA_1_B1233

CA_1_C1361

HI_1_A146 *

HI_1_B1534 *

HI_1_C1662 *

IA_1_A177

IA_1_B1835

IA_1_C1963

KY_1_A208

KY_1_B2136

KY_1_C2264

LA_1_A239

LA_1_B2437

LA_1_C2565

MO_1_A2610

MO_1_B2738

MO_1_C2866

MT_1_A2911

MT_1_B3039

MT_1_C3167

NM_1_A3212

NM_1_B3340

NM_1_C3468

NY_1_A4416 *

NY_1_B4544 *

NY_1_C4672 *

OH_1_A3513 *

OH_1_B3641 *

OH_1_C3769 *

PR_1_A3814 *

PR_1_B3942 *

PR_1_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 59

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 20. Fine-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A4717

CA_1_B4856

CA_1_C4973

HI_1_A5018

*

HI_1_B5155

*

HI_1_C5274

*

IA_1_A5319

IA_1_B5454

IA_1_C5575

KY_1_A5620

KY_1_B5753

KY_1_C5876

LA_1_A5921

LA_1_B6052

LA_1_C6177

MO_1_A6222

MO_1_B6351

MO_1_C6478

MT_1_A6523

MT_1_B6650

MT_1_C6779

NM_1_A6824

NM_1_B6949 (-40.14)

NM_1_C7080

NY_1_A7125

*

NY_1_A7125

*

NY_1_B7248

*

NY_1_B7248

*

NY_1_C7281

*

NY_1_C7281

*

OH_1_A7426

*

OH_1_B7547

*

OH_1_C7682

*

PR_1_A7727

*

PR_1_B7846

*

PR_1_C7983

*

PR_1_D0229

*

PR1E1060

*

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
60 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 21. Fine-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A1748293

CA_2_B17412393

CA_2_C17416693

HI_2_A1746293 * HI_2_B17415893 * HI_2_C17417693 * IA_2_A17413693

IA_2_B17416893

IA_2_C17417393

KY_2_A1741693

KY_2_B17412693

KY_2_C17418893

LA_2_A17413393

LA_2_B17415393

LA_2_C17415993

MO_2_A1749393

MO_2_B17412293

MO_2_C17414893

MT_2_A1742493

MT_2_B1744993

MT_2_C17413293

NM_2_A1745293

NM_2_B1749893

NM_2_C17418393

OH_2_A1749593 * OH_2_B17416293 * OH_2_C17417893 *

PR_2_A1746393

PR_2_B17414593

PR_2_C17414693

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available
REFERENCES 61

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 22. Fine-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A193293

CA_2_B1933493

CA_2_C1934993

HI_2_A1936993

* HI_2_B19315393 * HI_2_C19318793 * IA_2_A19310493 * IA_2_B19312193 * IA_2_C19314793 *

KY_2_A1933193

*

KY_2_B1934193

*

KY_2_C1939193

LA_2_A1931893

LA_2_B19310993

LA_2_C19317493

MO_2_A1938793

* MO_2_B19313493 * MO_2_C19317293

MT_2_A1934293

MT_2_B1938993

MT_2_C19312393

NM_2_A1933993

NM_2_B19311293

NM_2_C19316193

OH_2_A1931293

* OH_2_B1935893 * OH_2_C19319693 *

PR_2_A1934493

PR_2_B1933893

PR_2_C1935293

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
62 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 23. Fine-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A0101

CA_2_B0239

CA_2_C0357

HI_2_A0402 *

HI_2_B0538 *

HI_2_C0658 *

IA_2_A0703

IA_2_B0837

IA_2_C0959

KY_2_A1004

KY_2_B1136

KY_2_C1260

LA_2_A1305

LA_2_B1435

LA_2_C1561

MO_2_A1606 *

MO_2_B1734 *

MO_2_C1862

MT_2_A1907

MT_2_B2033

MT_2_C2163

NM_2_A2208

NM_2_B2332

NM_2_C2464

NY_2_A3412 *

NY_2_B3528 *

NY_2_C3668 *

OH_2_A2509 *

OH_2_B2631 *

OH_2_C2765 *

PR_2_A2810

PR_2_B2930

PR_2_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 63

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 24. Fine-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A115

CA_2_B1233

CA_2_C1361

HI_2_A146

*

HI_2_B1534

*

HI_2_C1662

*

IA_2_A177

IA_2_B1835

IA_2_C1963

KY_2_A208

KY_2_B2136

KY_2_C2264

LA_2_A239

LA_2_B2437

LA_2_C2565

MO_2_A2610

MO_2_B2738

MO_2_C2866

MT_2_A2911

MT_2_B3039

MT_2_C3167

NM_2_A3212

NM_2_B3340

NM_2_C3468

NY_2_A4416

*

NY_2_B4544

*

NY_2_C4672

*

OH_2_A3513

*

OH_2_B3641

*

OH_2_C3769

*

PR_2_A3814

PR_2_B3942

*

PR_2_C4070

*

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
64 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 25. Fine-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A8228

CA_2_B8145

CA_2_C8084

HI_2_A7927 *

HI_2_B7846 *

HI_2_C7783 *

IA_2_A7626

IA_2_B7547

IA_2_C7482

KY_2_A7325

KY_2_B7248

KY_2_C7181

LA_2_A7024

LA_2_B6949

LA_2_C6880

MO_2_A6723

MO_2_B6650

MO_2_C6579

MT_2_A6422

MT_2_B6351

MT_2_C6278

NM_2_A6121

NM_2_B6052 (-31.8)

NM_2_C5977

NY_2_A5820 *

NY_2_A5820 *

NY_2_B5753 *

NY_2_B5753 *

NY_2_C5676 *

NY_2_C5676 *

OH_2_A5519 *

OH_2_B5454 *

OH_2_C5375 *

PR_2_A5218 *

PR_2_B5155 *

PR_2_C5074 *

PR_2_D0229 *

PR2E1060 *

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
REFERENCES 65

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 26. Fine-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frostudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A1943393

CA_3_B1947893

CA_3_C195693

HI_3_A194393

*

HI_3_B1947493

*

HI_3_C1955093

*

IA_3_A1943293

IA_3_B1956093

IA_3_C1956393

KY_3_A1944493

KY_3_B1946393

KY_3_C1951493

LA_3_A1946093

LA_3_B195393

LA_3_C1956993

MO_3_A1945993

MO_3_B194793

MO_3_C1954193

MT_3_A1946993

MT_3_B1947993

MT_3_C1952493

NM_3_A194893

NM_3_B1948093

NM_3_C1957793

OH_3_A1942793

*

OH_3_B194693

* OH_3_C1955193 *

PR_3_A1944393

PR_3_B1944693

PR_3_C1955493

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available
66 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 27. Fine-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frostudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A1947693 *

CA_3_B195993 *

CA_3_C1958093

HI_3_A1944293 *

HI_3_B1951893 *

HI_3_C1956793 *

IA_3_A1945393 *

IA_3_B1952793 *

IA_3_C1955793 *

KY_3_A1946493 *

KY_3_B1951693 *

KY_3_C1953193

LA_3_A1942293

LA_3_B195793

LA_3_C1956693

MO_3_A1942493 * MO_3_B1951293 * MO_3_C1954693

MT_3_ B1951993

MT_3_A1941493

MT_3_C1954793

NM_3_A1943693

NM_3_B1953993

NM_3_C1956593

OH_3_A1944893 * OH_3_B1953293 * OH_3_C1956493 *

PR_3_A1945293

PR_3_B1951393

PR_3_C1952393

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 67

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 28. Fine-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frostudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A0101

CA_3_B0239

CA_3_C5757

HI_3_A0302

*

HI_3_B0438

*

HI_3_C5858

*

IA_3_A0503

IA_3_B0637

IA_3_C5959

KY_3_A0704

KY_3_B0836

KY_3_C6060

LA_3_A0905

LA_3_B1035

LA_3_C6161

MO_3_A1106

*

MO_3_B1234

*

MO_3_C6262

MT_3_A1307

MT_3_B1433

MT_3_C6363

NM_3_A1508

NM_3_B1632

NM_3_C6464

NY_3_A2613

*

NY_3_B2726

*

NY_3_C6868

*

OH_3_A1709

*

OH_3_B1831

*

OH_3_C6565

*

PR_3_A1910

PR_3_B2030

PR_3_C6666

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
68 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 29. Fine-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frostudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A115

CA_3_B1233

CA_3_C1361

HI_3_A146 *

HI_3_B1534 *

HI_3_C1662 *

IA_3_A177

IA_3_B1835

IA_3_C1963

KY_3_A208

KY_3_B2136

KY_3_C2264

LA_3_A239

LA_3_B2437

LA_3_C2565

MO_3_A2610

MO_3_B2738

MO_3_C2866

MT_3_A2911

MT_3_B3039

MT_3_C3167

NM_3_A3212 *

NM_3_B3340

NM_3_C3468

NY_3_A4416 *

NY_3_B4544 *

NY_3_C4672 *

OH_3_A3513 *

OH_3_B3641 *

OH_3_C3769 *

PR_3_A3814

PR_3_B3942

PR_3_C4070 *

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 69

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 30. Fine-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frostudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

FINE-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A0617

CA_3_B5756

CA_3_C5873

HI_3_A1018

*

HI_3_B5955

*

HI_3_C6074

*

IA_3_A4719

IA_3_B6154

IA_3_C6275

KY_3_A4820

KY_3_B6353

KY_3_C6476

LA_3_A4921

LA_3_B6552

LA_3_C6677

MO_3_A5022

MO_3_B6751

MO_3_C6878

MT_3_A5123

MT_3_B6950

MT_3_C7079

NM_3_A5224

NM_3_B7149

NM_3_C7280

NY_3_A5325

*

NY_3_A5325

*

NY_3_B7348

*

NY_3_B7348

*

NY_3_C7481

*

NY_3_C7481

*

OH_3_A5426

*

OH_3_B7547

*

OH_3_C7682

*

PR_3_A5527

*

PR_3_B7746

*

PR_3_C7883

*

PR_3_D0229

*

PR3E8460

*

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
70 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 31. Sand-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A180993

CA_1_B1802693

CA_1_C1884693

HI_1_A1884293 *

HI_1_B1885593 *

HI_1_C1886393 * IA_1_A18811893

IA_1_B18815893

IA_1_C18815893

KY_1_A18817793 (243.98)

KY_1_B18818793

KY_1_C18819793

LA_1_A18816493

LA_1_B18817693

LA_1_C18812693

MO_1_A18811393 (62.75)

MO_1_B18812393

MO_1_C18816693

MT_1_A18813393

MT_1_B18813693

MT_1_C18814493

NM_1_A18811493

NM_1_B18812293

NM_1_C18819493

OH_1_A18814793 * OH_1_B18817493 * OH_1_C18819093 * PR_1_A18812493

PR_1_B18818293

PR_1_C18819393

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available

Upper Control Limit at 75.09
REFERENCES 71

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 32. Sand-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A1902393

CA_1_B1903493

CA_1_C19011493

HI_1_A1905593

* HI_1_B19013893 * HI_1_C19019893 *

IA_1_A1903793

* IA_1_B19010093 * IA_1_C19017493 *

KY_1_A190493

*

KY_1_B1901393

*

KY_1_C1906993

LA_1_A1901293

LA_1_B19010693

LA_1_C19017393

MO_1_A1904293

* MO_1_B1908093 * MO_1_C19010293

MT_1_A1904993

MT_1_B19018793

* MT_1_C19012793

NM_1_A190893

NM_1_B19011893 (59.32)

NM_1_C19015393

OH_1_A1907193

* OH_1_B19015893 * OH_1_C19019693 *

PR_1_A190293

PR_1_B1901193

PR_1_C1902893

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab

Upper Control Limit at 59.46
72 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 33. Sand-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A0101

CA_1_B0238

CA_1_C0357

HI_1_A0402 *

HI_1_B0538 *

HI_1_C0658 *

IA_1_A0703

IA_1_B0837

IA_1_C0959

KY_1_A1004

KY_1_B1136

KY_1_C1260

LA_1_A1305

LA_1_B1435

LA_1_C1561

MO_1_A1106 *

MO_1_B1234 *

MO_1_C6262

MT_1_A1907

MT_1_B2033

MT_1_C2163

NM_1_A2208

NM_1_B2332

NM_1_C2464

NY_1_A3412 *

NY_1_B3528 *

NY_1_C3668 *

OH_1_A2509 *

OH_1_B2631 *

OH_1_C2765 *

PR_1_A2810

PR_1_B2930

PR_1_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 73

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 34. Sand-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A115

CA_1_B1233

CA_1_C1361

HI_1_A146

*

HI_1_B1534

*

HI_1_C1662

*

IA_1_A177

IA_1_B1835

IA_1_C1963

KY_1_A208

KY_1_B2136

KY_1_C2264

LA_1_A239

LA_1_B2437

LA_1_C2565

MO_1_A2610 (135.31)

MO_1_B2738 (88.11)

MO_1_C2866

MT_1_A2911

MT_1_B3039

MT_1_C3167

NM_1_A3212 (69.87)

NM_1_B3340

NM_1_C3468

NY_1_A4416

*

NY_1_B4544

*

NY_1_C4672

*

OH_1_A3513

*

OH_1_B3641

*

OH_1_C3769

*

PR_1_A3814

*

PR_1_B3942

*

PR_1_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
74 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 35. Sand-size material mass percent difference for samples containing 50 to 100 milligrams of fine-size material fromstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_1_A4717

CA_1_B4856

CA_1_C4973

HI_1_A5018 *

HI_1_B5155 *

HI_1_C5274 *

IA_1_A5319

IA_1_B5454

IA_1_C5575

KY_1_A5620

KY_1_B5753

KY_1_C5876

LA_1_A5921

LA_1_B6052

LA_1_C6177

MO_1_A6222

MO_1_B6351 (67.04)

MO_1_C6478

MT_1_A6523

MT_1_B6650

MT_1_C6779

NM_1_A6824 (81.79)

NM_1_B6949 (110.45)

NM_1_C7080

NY_1_A7125 *

NY_1_A7125 *

NY_1_B7248 *

NY_1_B7248 *

NY_1_C7281 *

NY_1_C7281 *

OH_1_A7426 *

OH_1_B7547 *

OH_1_C7682 *

PR_1_A7727 *

PR_1_B7846 *

PR_1_C7983 *

PR_1_D0229 *

PR1E1060 *

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
REFERENCES 75

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 36. Sand-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A1748293

CA_2_B17412393

CA_2_C17416693

HI_2_A1746293

* HI_2_B17415893 * HI_2_C17417693 * IA_2_A17413693

IA_2_B17416893

IA_2_C17417393

KY_2_A1741693

KY_2_B17412693

KY_2_C17418893

LA_2_A17413393

LA_2_B17415393

LA_2_C17415993

MO_2_A1749393

MO_2_B17412293

MO_2_C17414893

MT_2_A1742493

MT_2_B1744993

MT_2_C17413293

NM_2_A1745293 (55.48)

NM_2_B1749893

NM_2_C17418393

OH_2_A1749593

* OH_2_B17416293 * OH_2_C17417893 *

PR_2_A1746393

PR_2_B17414593

PR_2_C17414693

WA2A1749693

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available
76 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 37. Sand-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A193293

CA_2_B1933493

CA_2_C1934993

HI_2_A1936993 * HI_2_B19315393 * HI_2_C19318793 * IA_2_A19310493 * IA_2_B19312193 * IA_2_C19314793 *

KY_2_A1933193 *

KY_2_B1934193 *

KY_2_C1939193

LA_2_A1931893

LA_2_B19310993

LA_2_C19317493

MO_2_A1938793 * MO_2_B19313493 * MO_2_C19317293

MT_2_A1934293

MT_2_B1938993

MT_2_C19312393

NM_2_A1933993

NM_2_B19311293 (53.61)

NM_2_C19316193

OH_2_A1931293 * OH_2_B1935893 * OH_2_C19319693 *

PR_2_A1934493

PR_2_B1933893

PR_2_C1935293

WA2A19319393 

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab

Upper Control Limit at 59.09
REFERENCES 77

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 38. Sand-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A0101

CA_2_B0239

CA_2_C0357

HI_2_A0402

*

HI_2_B0538

*

HI_2_C0658

*

IA_2_A0703

IA_2_B0837

IA_2_C0959

KY_2_A1004

KY_2_B1136

KY_2_C1260

LA_2_A1305

LA_2_B1435

LA_2_C1561

MO_2_A1606

*

MO_2_B1734

*

MO_2_C1862

MT_2_A1907

MT_2_B2033

MT_2_C2163

NM_2_A2208

NM_2_B2332

NM_2_C2464

NY_2_A3412

*

NY_2_B3528

*

NY_2_C3668

*

OH_2_A2509

*

OH_2_B2631

*

OH_2_C2765

*

PR_2_A2810

PR_2_B2930

PR_2_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
78 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 39. Sand-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A115

CA_2_B1233

CA_2_C1361

HI_2_A146 *

HI_2_B1534 *

HI_2_C1662 *

IA_2_A177

IA_2_B1835

IA_2_C1963

KY_2_A208

KY_2_B2136

KY_2_C2264

LA_2_A239

LA_2_B2437

LA_2_C2565

MO_2_A2610 (91.02)

MO_2_B2738 (68.74)

MO_2_C2866

MT_2_A2911

MT_2_B3039

MT_2_C3167

NM_2_A3212 (116.28)

NM_2_B3340

NM_2_C3468

NY_2_A4416 *

NY_2_B4544 *

NY_2_C4672 *

OH_2_A3513 *

OH_2_B3641 *

OH_2_C3769 *

PR_2_A3814

PR_2_B3942 *

PR_2_C4070 *

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
REFERENCES 79

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 40. Sand-size material mass percent difference for samples containing 101 to 300 milligrams of fine-size material fromstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_2_A8228

CA_2_B8145

CA_2_C8084

HI_2_A7927

*

HI_2_B7846

*

HI_2_C7783

*

IA_2_A7626

IA_2_B7547

IA_2_C7482

KY_2_A7325

KY_2_B7248

KY_2_C7181

LA_2_A7024

LA_2_B6949

LA_2_C6880

MO_2_A6723 (56.62)

MO_2_B6650

MO_2_C6579

MT_2_A6422

MT_2_B6351

MT_2_C6278

NM_2_A6121 (57.88)

NM_2_B6052 (159.6)

NM_2_C5977

NY_2_A5820

*

NY_2_A5820

*

NY_2_B5753

*

NY_2_B5753

*

NY_2_C5676

*

NY_2_C5676

*

OH_2_A5519

*

OH_2_B5454

*

OH_2_C5375

*

PR_2_A5218

*

PR_2_B5155

*

PR_2_C5074

*

PR_2_D0229

*

PR2E1060

*

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
80 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 41. Sand-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frstudy number 96-1, which was completed in August 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A1943393

CA_3_B1947893

CA_3_C195693

HI_3_A194393 *

HI_3_B1947493 *

HI_3_C1955093 *

IA_3_A1943293

IA_3_B1956093

IA_3_C1956393

KY_3_A1944493

KY_3_B1946393

KY_3_C1951493

LA_3_A1946093

LA_3_B195393

LA_3_C1956993

MO_3_A1945993

MO_3_B194793

MO_3_C1954193

MT_3_A1946993

MT_3_B1947993

MT_3_C1952493

NM_3_A194893

NM_3_B1948093 (56.34)

NM_3_C1957793 (70.25)

OH_3_A1942793 *

OH_3_B194693 * OH_3_C1955193 *

PR_3_A1944393 (-50.31)

PR_3_B1944693

PR_3_C1955493

WA3A1941393

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available

Upper Control Limit at 50.87
REFERENCES 81

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 42. Sand-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frstudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A1947693

*

CA_3_B195993

*

CA_3_C1958093

HI_3_A1944293

*

HI_3_B1951893

*

HI_3_C1956793

*

IA_3_A1945393

*

IA_3_B1952793

*

IA_3_C1955793

*

KY_3_A1946493

*

KY_3_B1951693

*

KY_3_C1953193

LA_3_A1942293

LA_3_B195793

LA_3_C1956693

MO_3_A1942493

* MO_3_B1951293 * MO_3_C1954693

MT_3_ B1951993

MT_3_A1941493

MT_3_C1954793

NM_3_A1943693 (52.06)

NM_3_B1953993 (58.14)

NM_3_C1956593

OH_3_A1944893

* OH_3_B1953293 * OH_3_C1956493 *

PR_3_A1945293

PR_3_B1951393

PR_3_C1952393

WA3A1942693

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab

Upper Control Limit at 62.29
82 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 43. Sand-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material fstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A0101

CA_3_B0239

CA_3_C5757

HI_3_A0302 *

HI_3_B0438 *

HI_3_C5858 *

IA_3_A0503

IA_3_B0637

IA_3_C5959

KY_3_A0704

KY_3_B0836

KY_3_C6060

LA_3_A0905

LA_3_B1035

LA_3_C6161

MO_3_A1106 *

MO_3_B1234 *

MO_3_C6262

MT_3_A1307

MT_3_B1433

MT_3_C6363

NM_3_A1508

NM_3_B1632

NM_3_C6464

NY_3_A2613 *

NY_3_B2726 *

NY_3_C6868 *

OH_3_A1709 *

OH_3_B1831 *

OH_3_C6565 *

PR_3_A1910

PR_3_B2030

PR_3_C6666

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 83

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 44. Sand-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A115

CA_3_B1233

CA_3_C1361

HI_3_A146

*

HI_3_B1534

*

HI_3_C1662

*

IA_3_A177

IA_3_B1835

IA_3_C1963

KY_3_A208

KY_3_B2136

KY_3_C2264

LA_3_A239

LA_3_B2437

LA_3_C2565

MO_3_A2610

MO_3_B2738

MO_3_C2866

MT_3_A2911

MT_3_B3039

MT_3_C3167

NM_3_A3212

*

NM_3_B3340

NM_3_C3468

NY_3_A4416

*

NY_3_B4544

*

NY_3_C4672

*

OH_3_A3513

*

OH_3_B3641

*

OH_3_C3769

*

PR_3_A3814

PR_3_B3942

PR_3_C4070

*

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
84 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

0

10

-10

20

-20

30

-30

40

-40

50

-50

Figure 45. Sand-size material mass percent difference for samples containing 2,200 to 3,200 milligrams of fine-size material frstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SAND-SIZE MATERIAL MASS PERCENT DIFFERENCE

CA_3_A0617

CA_3_B5756

CA_3_C5873

HI_3_A1018 *

HI_3_B5955 *

HI_3_C6074 *

IA_3_A4719

IA_3_B6154

IA_3_C6275

KY_3_A4820

KY_3_B6353

KY_3_C6476

LA_3_A4921

LA_3_B6552 (-98.89)

LA_3_C6677

MO_3_A5022

MO_3_B6751

MO_3_C6878

MT_3_A5123

MT_3_B6950

MT_3_C7079

NM_3_A5224

NM_3_B7149

NM_3_C7280

NY_3_A5325 *

NY_3_A5325 *

NY_3_B7348 *

NY_3_B7348 *

NY_3_C7481 *

NY_3_C7481 *

OH_3_A5426 *

OH_3_B7547 *

OH_3_C7682 *

PR_3_A5527 *

PR_3_B7746 *

PR_3_C7883 *

PR_3_D0229 *

PR3E8460 *

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
REFERENCES 85

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 46. Suspended-sediment concentration percent difference for samples containing 50 to 100 milligrams of fine-size matestudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_1_A1902393

CA_1_B1903493

CA_1_C19011493

HI_1_A1905593

HI_1_B19013893

HI_1_C19019893

IA_1_A1903793

IA_1_B19010093

IA_1_C19017493

KY_1_A190493

KY_1_B1901393

KY_1_C1906993

LA_1_A1901293

LA_1_B19010693

LA_1_C19017393

MO_1_A1904293

* MO_1_B1908093 * MO_1_C19010293

MT_1_A1904993

MT_1_B19018793

* MT_1_C19012793

NM_1_A190893

NM_1_B19011893

NM_1_C19015393

OH_1_A1907193

OH_1_B19015893

OH_1_C19019693

PR_1_A190293 (44.3)

PR_1_B1901193 (43.86)

PR_1_C1902893

WA1A1905893

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
86 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 47. Suspended-sediment concentration percent difference for samples containing 50 to 100 milligrams of fine-size matstudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_1_A0101

CA_1_B0238

CA_1_C0357

HI_1_A0402

HI_1_B0538

HI_1_C0658

IA_1_A0703

IA_1_B0837

IA_1_C0959

KY_1_A1004

KY_1_B1136

KY_1_C1260

LA_1_A1305

LA_1_B1435

LA_1_C1561

MO_1_A1106

MO_1_B1234

MO_1_C6262

MT_1_A1907

MT_1_B2033

MT_1_C2163

NM_1_A2208

NM_1_B2332

NM_1_C2464

NY_1_A3412

NY_1_B3528

NY_1_C3668

OH_1_A2509

OH_1_B2631

OH_1_C2765

PR_1_A2810

PR_1_B2930

PR_1_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample arrived in questionab
REFERENCES 87

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 48. Suspended-sediment concentration percent difference for samples containing 50 to 100 milligrams of fine-size matstudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_1_A115

CA_1_B1233

CA_1_C1361

HI_1_A146

HI_1_B1534

HI_1_C1662

IA_1_A177

IA_1_B1835

IA_1_C1963

KY_1_A208

KY_1_B2136

KY_1_C2264

LA_1_A239

LA_1_B2437

LA_1_C2565

MO_1_A2610

MO_1_B2738

MO_1_C2866

MT_1_A2911

MT_1_B3039

MT_1_C3167

NM_1_A3212

NM_1_B3340

NM_1_C3468

NY_1_A4416

NY_1_B4544

NY_1_C4672

OH_1_A3513

OH_1_B3641

OH_1_C3769

PR_1_A3814

PR_1_B3942

PR_1_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample arrived in questionab
88 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 49. Suspended-sediment concentration percent difference for samples containing 50 to 100 milligrams of fine-size matstudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_1_A4717

CA_1_B4856

CA_1_C4973

HI_1_A5018

HI_1_B5155

HI_1_C5274

IA_1_A5319

IA_1_B5454

IA_1_C5575

KY_1_A5620

KY_1_B5753

KY_1_C5876

LA_1_A5921

LA_1_B6052

LA_1_C6177

MO_1_A6222

MO_1_B6351

MO_1_C6478

MT_1_A6523

MT_1_B6650

MT_1_C6779

NM_1_A6824

NM_1_B6949

NM_1_C7080

NY_1_A7125

NY_1_A7125

NY_1_B7248

NY_1_B7248

NY_1_C7281

NY_1_C7281

OH_1_A7426

OH_1_B7547

OH_1_C7682

PR_1_A7727

PR_1_B7846

PR_1_C7983

PR_1_D0229

PR1E1060

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample arrived in questionab
REFERENCES 89

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 50. Suspended-sediment concentration percent difference for samples containing 101 to 300 milligrams of fine-size mastudy number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_2_A193293

CA_2_B1933493

CA_2_C1934993

HI_2_A1936993

HI_2_B19315393

HI_2_C19318793

IA_2_A19310493

IA_2_B19312193

IA_2_C19314793

KY_2_A1933193

KY_2_B1934193

KY_2_C1939193

LA_2_A1931893

LA_2_B19310993

LA_2_C19317493

MO_2_A1938793

* MO_2_B19313493 * MO_2_C19317293

MT_2_A1934293

MT_2_B1938993

MT_2_C19312393

NM_2_A1933993

NM_2_B19311293

NM_2_C19316193

OH_2_A1931293

OH_2_B1935893

OH_2_C19319693

PR_2_A1934493 (41.93)

PR_2_B1933893 (53.13)

PR_2_C1935293

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

Sample out of range * Results not available Sample arrived in questionab
90 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 51. Suspended-sediment concentration percent difference for samples containing 101 to 300 milligrams of fine-size mastudy number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_2_A0101

CA_2_B0239

CA_2_C0357

HI_2_A0402

HI_2_B0538

HI_2_C0658

IA_2_A0703

IA_2_B0837

IA_2_C0959

KY_2_A1004

KY_2_B1136

KY_2_C1260

LA_2_A1305

LA_2_B1435

LA_2_C1561

MO_2_A1606

MO_2_B1734

MO_2_C1862

MT_2_A1907

MT_2_B2033

MT_2_C2163

NM_2_A2208

NM_2_B2332

NM_2_C2464

NY_2_A3412

NY_2_B3528

NY_2_C3668

OH_2_A2509

OH_2_B2631

OH_2_C2765

PR_2_A2810

PR_2_B2930

PR_2_C3066

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range Sample arrived in questionab
REFERENCES 91

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 52. Suspended-sediment concentration percent difference for samples containing 101 to 300 milligrams of fine-size mastudy number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_2_A115

CA_2_B1233

CA_2_C1361

HI_2_A146

HI_2_B1534

HI_2_C1662

IA_2_A177

IA_2_B1835

IA_2_C1963

KY_2_A208

KY_2_B2136

KY_2_C2264

LA_2_A239

LA_2_B2437

LA_2_C2565

MO_2_A2610

MO_2_B2738

MO_2_C2866

MT_2_A2911

MT_2_B3039

MT_2_C3167

NM_2_A3212

NM_2_B3340

NM_2_C3468

NY_2_A4416

NY_2_B4544

NY_2_C4672

OH_2_A3513

OH_2_B3641

OH_2_C3769

PR_2_A3814

PR_2_B3942

PR_2_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample arrived in questionab
92 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 53. Suspended-sediment concentration percent difference for samples containing 101 to 300 milligrams of fine-size mastudy number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_2_A8228

CA_2_B8145

CA_2_C8084

HI_2_A7927

HI_2_B7846

HI_2_C7783

IA_2_A7626

IA_2_B7547

IA_2_C7482

KY_2_A7325

KY_2_B7248

KY_2_C7181

LA_2_A7024

LA_2_B6949

LA_2_C6880

MO_2_A6723

MO_2_B6650

MO_2_C6579

MT_2_A6422

MT_2_B6351

MT_2_C6278

NM_2_A6121

NM_2_B6052

NM_2_C5977

NY_2_A5820

NY_2_A5820

NY_2_B5753

NY_2_B5753

NY_2_C5676

NY_2_C5676

OH_2_A5519

OH_2_B5454

OH_2_C5375

PR_2_A5218

PR_2_B5155

PR_2_C5074

PR_2_D0229

PR2E1060

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample arrived in questionab
REFERENCES 93

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 54. Suspended-sediment concentration percent difference for samples containing 2,200 to 3,200 milligrams of fine-size study number 96-2, which was completed in September 1996.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_3_A1947693

*

CA_3_B195993

*

CA_3_C1958093

HI_3_A1944293

HI_3_B1951893

HI_3_C1956793

IA_3_A1945393

IA_3_B1952793

IA_3_C1955793

KY_3_A1946493

KY_3_B1951693

KY_3_C1953193

LA_3_A1942293

LA_3_B195793

LA_3_C1956693

MO_3_A1942493

* MO_3_B1951293 * MO_3_C1954693

MT_3_ B1951993

MT_3_A1941493

MT_3_C1954793

NM_3_A1943693

NM_3_B1953993

NM_3_C1956593

OH_3_A1944893

OH_3_B1953293

OH_3_C1956493

PR_3_A1945293

PR_3_B1951393

PR_3_C1952393

WA3A1942693

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew Mexico

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
94 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 55. Suspended-sediment concentration percent difference for samples containing 2,200 to 3,200 milligrams of fine-size study number 97-1, which was completed in July 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_3_A0101

CA_3_B0239

CA_3_C5757

HI_3_A0302

HI_3_B0438

HI_3_C5858

IA_3_A0503

IA_3_B0637

IA_3_C5959

KY_3_A0704

KY_3_B0836

KY_3_C6060

LA_3_A0905

LA_3_B1035

LA_3_C6161

MO_3_A1106

MO_3_B1234

MO_3_C6262

MT_3_A1307

MT_3_B1433

MT_3_C6363

NM_3_A1508

NM_3_B1632

NM_3_C6464

NY_3_A2613

NY_3_B2726

NY_3_C6868 *

OH_3_A1709

OH_3_B1831

OH_3_C6565

PR_3_A1910

PR_3_B2030

PR_3_C6666

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
REFERENCES 95

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 56 . Suspended-sediment concentration percent difference for samples containing 2,200 to 3,200 milligrams of fine-size study number 97-2, which was completed in September 1997.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_3_A115

CA_3_B1233

CA_3_C1361

HI_3_A146

HI_3_B1534

HI_3_C1662

IA_3_A177

IA_3_B1835

IA_3_C1963

KY_3_A208

KY_3_B2136

KY_3_C2264

LA_3_A239

LA_3_B2437

LA_3_C2565

MO_3_A2610

MO_3_B2738

MO_3_C2866

MT_3_A2911

MT_3_B3039

MT_3_C3167

NM_3_A3212

*

NM_3_B3340

NM_3_C3468

NY_3_A4416

NY_3_B4544

NY_3_C4672

OH_3_A3513

OH_3_B3641

OH_3_C3769

PR_3_A3814

PR_3_B3942

PR_3_C4070

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigm

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

* Results not available Sample arrived in questionab
96 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 57. Suspended-sediment concentration percent difference for samples containing 2,200 to 3,200 milligrams of fine-size study number 98-1, which was completed in June 1998.

EXPLANATION

SAMPLE IDENTIFICATION NUMBER

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

CA_3_A0617

CA_3_B5756

CA_3_C5873

HI_3_A1018

HI_3_B5955

HI_3_C6074

IA_3_A4719

IA_3_B6154

IA_3_C6275

KY_3_A4820

KY_3_B6353

KY_3_C6476

LA_3_A4921

LA_3_B6552

LA_3_C6677

MO_3_A5022

MO_3_B6751

MO_3_C6878

MT_3_A5123

MT_3_B6950

MT_3_C7079

NM_3_A5224

NM_3_B7149

NM_3_C7280

NY_3_A5325

NY_3_A5325

NY_3_B7348

NY_3_B7348

NY_3_C7481

NY_3_C7481

OH_3_A5426

OH_3_B7547

OH_3_C7682

PR_3_A5527

PR_3_B7746

PR_3_C7883

PR_3_D0229

PR3E8460 (57.6)

Median +1 and -1 F-Psuedosigma

California

+2 and -2 F-Psuedosigma

Hawaii

+3 and -3 F-Psuedosigma

Iowa

KentuckyLouisianaMissouri

MontanaNew MexicoNew York (contract laboratory)

Ohio (contract laboraPuerto RicoWashington

Sample out of range Sample arrived in questionab
REFERENCES 97

CA HI IA KY LA MO MT NM NY OH PR 

LABORATORIES

0

2

468

1012

14

1618

1 1

Figure 58. Sample leakage by laboratory, August 1996 through June 1998.

This is a contract laboratory.

NUMBER OF SAMPLES WHERE LEAKAGE WAS REPORTED

1
98 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

Figure 59. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Salinas, California, laboratory.
REFERENCES 99

05

-5

10

-10

15

-15

20

-20

Figure 60. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Honolulu, Hawaii, laboratory.
100 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

Figure 61. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Iowa City, Iowa, laboratory.
REFERENCES 101

05

-5

10

-10

15

-15

20

-20

Figure 62. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Louisville, Kentucky, laboratory.
102 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

Figure 63. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Baton Rouge, Louisiana, laboratory.
REFERENCES 103

05

-5

10

-10

15

-15

20

-20

Figure 64. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Rolla, Missouri, laboratory.
104 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

Figure 65. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Helena, Montana, laboratory.
REFERENCES 105

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 66. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Albuquerque, New Mexico, laboratory.
106 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

35

-35

Figure 67. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

for samples containing 50 to 100 milligrams of sediment for the Ithaca, New York, (contract) laboratory.

Did not participate Comparison analysis using a millipo

*

96-2 97-1 97-2 98-1

*
REFERENCES 107

05

-5

10

-10

15

-15

20

-20

Figure 68. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Columbus, Ohio (contract), laboratory.
108 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

Figure 69. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Guaynabo, Puerto Rico, laboratory.
REFERENCES 109

05

-5

10

-10

15

-15

20

-20

Figure 70. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 50 to 100 milligrams of sediment for the Vancouver, Washington, laboratory.
110 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 71. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Salinas, California, laboratory.
REFERENCES 111

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 72. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Honolulu, Hawaii, laboratory.
112 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 73. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Iowa City, Iowa, laboratory.
REFERENCES 113

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 74. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Louisville, Kentucky, laboratory.
114 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 75. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Baton Rouge, Louisiana, laboratory.
REFERENCES 115

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 76. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Rolla, Missouri, laboratory.
116 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 77. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Helena, Montana, laboratory.
REFERENCES 117

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 78. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Albuquerque, New Mexico, laboratory.
118 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

30

-30

Figure 79. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Ithaca, New York, (contract) laboratory.

Comparison analysis using a millipo

96-2

*

Did not participate

*
REFERENCES 119

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 80. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Columbus, Ohio (contract), laboratory.
120 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 81. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Guaynabo, Puerto Rico, laboratory.
REFERENCES 121

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 82. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 101 to 300 milligrams of sediment for the Vancouver, Washington, laboratory.
122 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 83. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Salinas, California, laboratory.
REFERENCES 123

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 84. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Honolulu, Hawaii, laboratory.
124 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 85. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Iowa City, Iowa, laboratory.
REFERENCES 125

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 86. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Louisville, Kentucky, laboratory.
126 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 87. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Baton Rouge, Louisiana, laboratory.
REFERENCES 127

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 88. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Rolla, Missouri, laboratory.
128 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 89. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Helena, Montana, laboratory.
REFERENCES 129

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 90. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Albuquerque, New Mexico, laboratory.
130 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 91. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE

for samples containing 2,200 to 3,200 milligrams of sediment for the Ithaca, New York, (contract) laboratory.

96-2 97-1 97-2 98-1

*

Did not participate Comparison analysis using a millipo

*
REFERENCES 131

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 92. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Columbus, Ohio (contract), laboratory.
132 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 93. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Guaynabo, Puerto Rico, laboratory.
REFERENCES 133

05

-5

10

-10

15

-15

20

-20

25

-25

Figure 94. Suspended-sediment concentration percent difference for study numbers 96-2 through 98-1 

SEDIMENT LABORATORY QUALITY-ASSURANCE STUDY

SUSPENDED-SEDIMENT CONCENTRATION PERCENT DIFFERENCE 96-2 97-1 97-2 98-1

for samples containing 2,200 to 3,200 milligrams of sediment for the Vancouver, Washington, laboratory.
134 Laboratory Performance in the Sediment Laboratory Quality-Assurance Project, 1996-98 PERCENT DIFFERENCE FROM KNOWN VALUES

CA HI IA KY LA MO MT NM NY OH PR WA

-25

-20

-15

-10

-5

0

5

10

Figure 95. Distribution of reported values for each laboratory that participated in the 

Sediment Laboratory Quality-Assurance project from August 1996 to June 1998: (A) 

percent differences for suspended-sediment concentration, (B) percent differences for 

mass of fine material, (C) percent differences for mass of sand material.

-20

-10

0

10

20

30

40

50

A

B

upper quartile of the 

laboratory's reported 

results

median of the 

laboratory's reported 

results

lower quartile of the 

laboratory's reported 

results

-15

-10

-5

0

5

C

1 1

1

This is a contract laboratory.

CA HI IA KY LA MO MT NM NY OH PR WA 1 1

CA HI IA KY LA MO MT NM NY OH PR WA 1 1
Gordon and others

—LABORATORY PERFORMANCE IN THE SEDIMENT LABORATORY

 QUALITY-ASSURANCE PROJECT, 1996-98

Since 1879, the U.S. Geological Survey has been providing maps, reports, and information to help others

who manage, develop, and protect our Nation’s water, energy, mineral, land, and biological resources. We

help nd natural resources needed to build tomorrow and supply scienti c understanding needed to help

minimize or mitigate the effects of natural hazards and the environmental damage caused by human

activities. The results of our efforts touch the daily lives of almost everyone. 

U.S. Geological Survey

Branch of Quality Systems

Box 25086, MS 401

Denver Federal Center

Denver, CO 80225

USGS/WRIR 99-4184