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USGS WATER, ENERGY, AND BIOGEOCHEMICAL BUDGETS (WEBB) LABORATORY
Fine Sediment Separation Results
Results include determination of fine material (<0.063 mm) mass for each SLQA study. A highlighted value exceeds study's
control limits, for a specific size class. Laboratories analyze 9 samples in each study. 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).
    Fine Material Mass Results
Class Sample Target Fine Median Percent  Lower Control Reported Laboratory  Upper Control
  Id Material Difference  Limit  Results Percent  Limit 
    Mass (g) (%) (%) Difference (%) (%)
Study 2, 1998 (Oct - Dec)  
1 A4014 0.061 -6.19 -24.59 12.21
1 B3942 0.061 -6.19 -24.59 -7.85 12.21
1 C3870 0.061 -6.19 -24.59 12.21
2 A4014 0.120 -4.82 -15.52 5.88
2 B3942 0.120 -4.82 -15.52 -5.88 5.88
2 C3870 0.120 -4.82 -15.52 5.88
3 A4314 2.400 -2.61 -9.15 -2.70 3.94
3 B4242 2.600 -2.61 -9.15 -2.40 3.94
3 C4170 2.600 -2.61 -9.15 3.94
   
Study 1, 1999 (Apr - May)  
1 A3385 0.061 -7.01 -18.45 4.43
1 B3448 0.061 -7.01 -18.45 4.43
1 C5686 0.058 -7.01 -18.45 4.43
2 A7454 0.116 -5.46 -12.10 1.18
2 B7383 0.116 -5.46 -12.10 1.18
2 C1888 0.120 -5.46 -12.10 1.18
3 A5187 2.400 -3.25 -10.36 3.86
3 B5293 2.400 -3.25 -10.36 -3.57 3.86
3 C5188 2.300 -3.25 -10.36 3.86
   
Study 2, 1999 (Sep - Oct)  
1 A4317 0.060 -4.30 -16.72 8.11
1 B4443 0.060 -4.30 -16.72 8.11
1 C4575 0.060 -4.30 -16.72 8.11
2 A4340 0.150 -4.90 -11.96 2.16
2 B4412 0.150 -4.90 -11.96 2.16
2 C4575 0.150 -4.90 -11.96 2.16
3 A4511 2.500 -1.40 -6.87 -1.36 4.08
3 B4643 2.500 -1.40 -6.87 -1.43 4.08
3 C4767 2.500 -1.40 -6.87 -2.03 4.08
   
Study 1, 2000 (May - Jun)  
1 A1414 0.080 -4.49 -13.45 4.46
1 B4444 0.080 -4.49 -13.45 4.46
1 C7474 0.080 -4.49 -13.45 4.46
2 A1414 0.200 -3.10 -11.51 5.32
2 B4545 0.200 -3.10 -11.51 5.32
2 C7373 0.200 -3.10 -11.51 5.32
3 A2020 2.200 0.21 -3.65 -0.92 4.07
3 B4444 2.200 0.21 -3.65 -0.65 4.07
3 C7474 2.200 0.21 -3.65 4.07
   
Study 2, 2000 (Oct - Nov)  
1 A1717 0.100 14.84 -126.98 156.66
1 B4444 0.100 14.84 -126.98 156.66
1 C7474 0.100 14.84 -126.98 156.66
2 A1414 0.220 1.74 -49.81 53.30
2 B4444 0.220 1.74 -49.81 53.30
2 C7474 0.220 1.74 -49.81 53.30
3 A1414 2.500 -1.25 -6.34 -1.39 3.83
3 B4444 2.500 -1.25 -6.34 1.68 3.83
3 C7474 2.500 -1.25 -6.34 -5.74 3.83
   
Study 1, 2001 (Jul - Sep)  
1 A2020 0.100 -3.85 -9.98 -4.15 2.29
1 B5050 0.100 -3.85 -9.98 2.29
1 C8080 0.100 -3.85 -9.98 2.29
2 A1104 0.300 -2.74 -7.03 1.55
2 B5056 0.300 -2.74 -7.03 1.55
2 C7164 0.300 -2.74 -7.03 1.55
3 A0702 2.400 -1.45 -6.51 -1.73 3.60
3 B3139 2.400 -1.45 -6.51 3.60
3 C8976 2.400 -1.45 -6.51 -1.61 3.60
   
Study 2, 2001 (Oct - Jan)  
1 A0421 0.080 -3.97 -30.28 22.34
1 B5541 0.080 -3.97 -30.28 22.34
1 C8662 0.080 -3.97 -30.28 22.34
2 A2130 0.250 -3.79 -13.27 5.69
2 B5555 0.250 -3.79 -13.27 5.69
2 C7087 0.250 -3.79 -13.27 5.69
3 A1014 2.200 -1.46 -6.53 -1.88 3.62
3 B4931 2.200 -1.46 -6.53 -1.69 3.62
3 C6263 2.200 -1.46 -6.53 -2.18 3.62
   
WEBB laboratory ceased analyzing SLQA samples for fine/sand separation after 2001.  
WEBB Sand Separation WEBB Sediment Mass Results WEBB Suspended Sediment Concentration