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USGS UPPER MIDWEST ENVIRONMENTAL SCIENCES CENTER (BRD) LABORATORY 
Suspended Sediment Concentration 
Results include determination of suspended sediment concentration. 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).
    Suspended Sediment Concentration Results
Class Sample Id Target Suspended Median Percent  Lower Control Reported Laboratory  Upper Control
  Sediment  Difference  Limit  Results Percent  Limit 
    Concentration (mg/L) (%) (%) Difference (%) (%)
Study 2, 2004 (Nov - Dec)  
1 A6049 165 -4.85 -21.37 -11.40 11.66
1 B5668 166 -4.85 -21.37 -10.68 11.66
1 C0930 180 -4.85 -21.37 -16.56 11.66
2 A2822 1836 -2.08 -8.96 -8.35 4.80
2 B4444 1835 -2.08 -8.96 -8.11 4.80
2 C3128 1836 -2.08 -8.96 -8.92 4.80
3 A1954 8801 -0.91 -4.25 -0.91 2.43
3 B3743 8801 -0.91 -4.25 -4.44 2.43
3 C1508 6601 -0.91 -4.25 -1.32 2.43
   
Study 1, 2005 (May - Jul)  
1 A5921 402 -2.84 -10.41 -4.99 4.73
1 B5345 401 -2.84 -10.41 -4.48 4.73
1 C1239 481 -2.84 -10.41 -4.93 4.73
2 A5655 1202 -3.44 -12.11 -4.89 5.22
2 B3526 1201 -3.44 -12.11 -4.25 5.22
2 C1140 1601 -3.44 -12.11 -3.69 5.22
3 A1135 9003 -1.89 -6.68 -2.77 2.90
3 B0662 9002 -1.89 -6.68 -2.75 2.90
3 C4408 9002 -1.89 -6.68 -2.19 2.90
   
Study 2, 2005 (Nov - Dec)  
1 A3208 134 -4.94 -23.19 13.31
1 B0215 134 -4.94 -23.19 -15.29 13.31
1 C7068 134 -4.94 -23.19 -23.32 13.31
2 A3217 3300 -1.39 -4.23 -1.23 1.46
2 B3177 3301 -1.39 -4.23 -5.25 1.46
2 C6915 3301 -1.39 -4.23 -1.15 1.46
3 A7217 9689 -2.05 -7.14 -3.63 3.04
3 B0414 9690 -2.05 -7.14 -2.68 3.04
3 C5657 9690 -2.05 -7.14 -2.65 3.04
   
Study 1, 2006 (May - Jun)  
1 A1018 187 -3.20 -11.20 -10.60 4.70
1 B0477 187 -3.20 -11.20 -11.80 4.70
1 C2314 187 -3.20 -11.20 -9.73 4.70
2 A3512 2400 -1.10 -5.20 -2.34 3.00
2 B6661 2400 -1.10 -5.20 -4.08 3.00
2 C4518 2400 -1.10 -5.20 -2.88 3.00
3 A5571 9800 -1.80 -6.90 -2.98 3.30
3 B0413 9800 -1.80 -6.90 -3.05 3.30
3 C3370 9800 -1.80 -6.90 -3.71 3.30
Laboratory discontinued evaluating water-sediment samples and had no further need to participate in the SLQA.
BRD Sediment Mass Results