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USGS UPPER MIDWEST ENVIRONMENTAL SCIENCES CENTER (BRD) LABORATORY 
Sediment Mass Results
Results include determination of sediment mass. Target values are determined gravimetrically during sample preparation. 
Median percent differences are calculated using all submitted analyses by participants for each sample class. 
Upper and lower control limits are +/-3 f-pseudosigma from median, respectively. F-pseudosigma = (Interquartile range)/1.349.
Reported laboratory results percent difference = (((Reported value - Target value)/(Target value)) * 100).
    Sediment Mass Results
Class Sample Id Target Sediment Median Percent  Lower Control Reported Laboratory  Upper Control
  Mass  Difference  Limit  Results Percent  Limit 
    (g) (%) (%) Difference (%) (%)
Study 2, 2004 (Nov - Dec)  
1 A6049 0.066 -5.01 -20.47 -11.85 10.44
1 B5668 0.067 -5.01 -20.47 -11.10 10.44
1 C0930 0.072 -5.01 -20.47 -17.18 10.44
2 A2822 0.275 -2.82 -10.38 -9.03 4.73
2 B4444 0.275 -2.82 -10.38 -8.68 4.73
2 C3128 0.275 -2.82 -10.38 -9.35 4.73
3 A1954 2.640 -1.07 -3.72 -0.75 1.57
3 B3743 2.640 -1.07 -3.72 -4.28 1.57
3 C1508 2.640 -1.07 -3.72 -1.31 1.57
   
Study 1, 2005 (May - Jul)  
1 A5921 0.120 -2.96 -10.38 -5.53 4.46
1 B5345 0.120 -2.96 -10.38 -5.03 4.46
1 C1239 0.120 -2.96 -10.38 -5.45 4.46
2 A5655 0.240 -3.48 -11.39 -5.53 4.43
2 B3526 0.240 -3.48 -11.39 -4.84 4.43
2 C1140 0.240 -3.48 -11.39 -4.56 4.43
3 A1135 3.601 -1.69 -5.99 -2.38 2.62
3 B0662 3.601 -1.69 -5.99 -2.37 2.62
3 C4408 3.601 -1.69 -5.99 -1.84 2.62
   
Study 2, 2005 (Nov - Dec)  
1 A3208 0.060 -5.77 -23.84 12.29
1 B0215 0.060 -5.77 -23.84 -15.81 12.29
1 C7068 0.060 -5.77 -23.84 -23.82 12.29
2 A3217 1.485 -1.82 -4.56 -1.62 0.92
2 B3177 1.485 -1.82 -4.56 -5.56 0.92
2 C6915 1.485 -1.82 -4.56 -1.56 0.92
3 A7217 4.360 -2.19 -7.07 -3.34 2.68
3 B0414 4.361 -2.19 -7.07 -2.35 2.68
3 C5657 4.361 -2.19 -7.07 -2.31 2.68
   
   
Study 1, 2006 (May - Jun)  
1 A1018 0.084 -3.90 -11.30 -11.22 3.60
1 B0477 0.084 -3.90 -11.30 -12.54 3.60
1 C2314 0.084 -3.90 -11.30 -10.33 3.60
2 A3512 1.080 -1.50 -5.40 -2.80 2.40
2 B6661 1.080 -1.50 -5.40 -4.50 2.40
2 C4518 1.080 -1.50 -5.40 -3.29 2.40
3 A5571 4.410 -1.70 -5.50 -2.63 2.10
3 B0413 4.410 -1.70 -5.50 -2.75 2.10
3 C3370 4.410 -1.70 -5.50 -3.39 2.10
Laboratory discontinued evaluating water-sediment samples and had no further need to participate in the SLQA.
BRD Suspended Sediment Concentration Results