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USGS LOUISIANA 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 Target Suspended Median Percent  Lower Control Reported Laboratory  Upper Control
  Id Sediment  Difference  Limit  Results Percent  Limit 
    Concentration (mg/L) (%) (%) Difference (%) (%)
Study 1, 1997 (Jul - Aug)  
1 A1305 255 -3.60 -13.21 -6.74 6.01
1 B1435 274 -3.60 -13.21 -1.97 6.01
1 C1561 187 -3.60 -13.21 -7.36 6.01
2 A1305 505 -3.38 -14.40 -3.80 7.64
2 B1435 534 -3.38 -14.40 -0.30 7.64
2 C1561 354 -3.38 -14.40 16.47 7.64
3 A0905 10759 -0.36 -8.85 -2.48 8.13
3 B1035 11404 -0.36 -8.85 -6.83 8.13
3 C6161 7560 -0.36 -8.85 16.22 8.13
   
Study 2, 1997 (Nov - Dec)  
1 A239 253 -2.91 -10.81 -4.67 4.99
1 B2437 274 -2.91 -10.81 -2.92 4.99
1 C2565 181 -2.91 -10.81 -2.90 4.99
2 A239 507 -3.77 -13.12 -5.68 5.59
2 B2437 530 -3.77 -13.12 -3.51 5.59
2 C2565 357 -3.77 -13.12 -3.01 5.59
3 A239 10760 -0.72 -3.81 -1.94 2.38
3 B2437 11407 -0.72 -3.81 -0.38 2.38
3 C2565 6558 -0.72 -3.81 -1.27 2.38
   
Study 1, 1998 (May - Jun)  
1 A5921 188 -4.86 -16.80 1.75 7.09
1 B6052 168 -4.86 -16.80 -0.90 7.09
1 C6177 245 -4.86 -16.80 0.54 7.09
2 A7024 362 -5.48 -17.52 -5.88 6.55
2 B6949 332 -5.48 -17.52 -2.34 6.55
2 C6880 477 -5.48 -17.52 -3.56 6.55
3 A4921 7690 -1.27 -16.04 -7.10 13.50
3 B6552 8124 -1.27 -16.04 -0.36 13.50
3 C6677 10073 -1.27 -16.04 0.44 13.50
   
Study 2, 1998 (Oct - Dec)  
1 A5921 94 -2.06 -17.51 8.20 13.40
1 B6060 201 -2.06 -17.51 5.34 13.40
1 C6177 267 -2.06 -17.51 6.98 13.40
2 A7024 174 -2.38 -11.60 4.52 6.83
2 B6949 360 -2.38 -11.60 5.28 6.83
2 C6880 501 -2.38 -11.60 6.72 6.83
3 A1321 3618 -0.28 -3.08 -0.24 2.52
3 B6552 8125 -0.28 -3.08 0.06 2.52
3 C6677 9101 -0.28 -3.08 -0.40 2.52
   
Study 1, 1999 (Apr - May)  
1 A1109 279 -2.19 -13.76 1.87 9.38
1 B1238 285 -2.19 -13.76 1.12 9.38
1 C4574 147 -2.19 -13.76 -7.91 9.38
2 A4849 532 -2.97 -9.67 -6.84 3.72
2 B4980 574 -2.97 -9.67 -4.07 3.72
2 C0662 305 -2.97 -9.67 -2.82 3.72
3 A2368 10112 -0.43 -4.07 -1.39 3.22
3 B2209 10855 -0.43 -4.07 -1.17 3.22
3 C4075 5245 -0.43 -4.07 -1.85 3.22
   
Study 2, 1999 (Sep - Oct)  
1 A1676 341 -2.54 -16.98 -8.21 11.90
1 B1716 289 -2.54 -16.98 -2.08 11.90
1 C1848 242 -2.54 -16.98 -7.44 11.90
2 A1619 628 -1.25 -11.52 22.37 9.02
2 B1736 830 -1.25 -11.52 -2.95 9.02
2 C1866 860 -1.25 -11.52 96.16 9.02
3 A1816 13946 -0.71 -4.22 -0.67 2.79
3 B1940 14615 -0.71 -4.22 -0.63 2.79
3 C2070 12368 -0.71 -4.22 8.75 2.79
   
Study 1, 2000 (May - Jun)  
1 A0505 445 -2.87 -11.78 -7.67 6.03
1 B3535 463 -2.87 -11.78 0.00 6.03
1 C6565 386 -2.87 -11.78 -7.35 6.03
2 A0505 1126 -1.63 -8.81 -0.80 5.56
2 B3535 1167 -1.63 -8.81 -4.84 5.56
2 C.6565 980 -1.63 -8.81 1.27 5.56
3 A0909 12649 -0.05 -3.89 -0.54 3.80
3 B3535 13195 -0.05 -3.89 -1.19 3.80
3 C6565 10999 -0.05 -3.89 -0.07 3.80
   
Study 2, 2000 (Oct - Nov)  
1 A0808 573 10.49 -105.07 -4.19 126.05
1 B3535 591 10.49 -105.07 20.07 126.05
1 C6565 417 10.49 -105.07 5.60 126.05
2 A0505 1267 2.06 -45.61 1.42 49.72
2 B3535 1289 2.06 -45.61 39.57 49.72
2 C.6565 918 2.06 -45.61 -8.57 49.72
3 A0505 13978 -0.92 -5.78 -1.17 3.93
3 B3535 14649 -0.92 -5.78 -1.78 3.93
3 C6565 10415 -0.92 -5.78 29.47 3.93
   
Study 1, 2001 (Jul - Sep)  
1 A1010 600 -2.17 -10.36 -5.25 6.02
1 B4040 587 -2.17 -10.36 -2.90 6.02
1 C7070 416 -2.17 -10.36 -13.94 6.02
2 A2113 1726 -1.73 -5.96 -2.43 2.49
2 B4045 1760 -1.73 -5.96 -2.47 2.49
2 C8184 1254 -1.73 -5.96 -3.56 2.49
3 A1121 13565 -0.34 -3.89 -1.26 3.22
3 B5842 14042 -0.34 -3.89 -1.39 3.22
3 C8886 10004 -0.34 -3.89 7.48 3.22
   
Study 2, 2001 (Oct - Jan)  
1 A2401 449 -1.44 -20.24 3.94 17.35
1 B5032 459 -1.44 -20.24 5.81 17.35
1 C6563 326 -1.44 -20.24 16.17 17.35
2 A2609 1419 -2.30 -8.73 -1.34 4.13
2 B5060 1447 -2.30 -8.73 0.60 4.13
2 C6576 1041 -2.30 -8.73 0.28 4.13
3 A1707 12302 -0.46 -4.76 -0.46 3.83
3 B3258 12988 -0.46 -4.76 -77.66 3.83
3 C7986 9171 -0.46 -4.76 -0.53 3.83
   
Study 1, 2002 (Jul - Sep)  
1 A1430 330 -0.89 -22.90 0.58 21.12
1 B5847 344 -0.89 -22.90 0.48 21.12
1 C8480 247 -0.89 -22.90 7.03 21.12
2 A2310 713 -2.79 -10.92 -2.14 5.34
2 B3746 750 -2.79 -10.92 -2.48 5.34
2 C7476 517 -2.79 -10.92 2.30 5.34
3 A0909 12404 -0.89 -4.38 -0.82 2.59
3 B3952 13001 -0.89 -4.38 -1.25 2.59
3 C6789 9068 -0.89 -4.38 -1.44 2.59
   
Study 2, 2002 (Nov - Dec)  
1 A0718 358 -0.68 -12.20 -0.70 10.85
1 B4250 371 -0.68 -12.20 12.01 10.85
1 C7980 398 -0.68 -12.20 12.56 10.85
2 A1601 579 -0.92 -13.18 3.63 11.35
2 B5747 593 -0.92 -13.18 8.19 11.35
2 C7687 637 -0.92 -13.18 9.51 11.35
3 A1727 8105 0.09 -5.67 1.96 5.85
3 B6008 8107 0.09 -5.67 5.39 5.85
3 C8678 9222 0.09 -5.67 1.00 5.85
   
Study 1, 2003 (Jun - Aug)  
1 A4629 289 -3.28 -10.76 -3.39 4.19
1 B5006 310 -3.28 -10.76 -4.75 4.19
1 C5501 325 -3.28 -10.76 -5.75 4.19
2 A3247 1009 -2.46 -6.83 -3.68 1.90
2 B5916 1103 -2.46 -6.83 -3.55 1.90
2 C1220 1157 -2.46 -6.83 -3.59 1.90
3 A5101 8101 -0.73 -3.58 -0.74 2.12
3 B0658 9028 -0.73 -3.58 0.48 2.12
3 C4750 9260 -0.73 -3.58 -0.81 2.12
   
Study 2, 2003 (Dec - Feb)  
1 A0546 138 -3.00 -17.79 -1.45 11.80
1 B3420 139 -3.00 -17.79 -6.86 11.80
1 C2356 151 -3.00 -17.79 19.40 11.80
2 A0208 1027 -1.50 -4.79 10.38 1.79
2 B5030 1032 -1.50 -4.79 -2.71 1.79
2 C3222 1122 -1.50 -4.79 -1.28 1.79
3 A4605 10272 -0.57 -3.27 -0.60 2.13
3 B5421 10268 -0.57 -3.27 -0.43 2.13
3 C0539 11201 -0.57 -3.27 -0.54 2.13
   
Study 1, 2004 (Jun - Jul)  
1 A4504 249 -4.33 -14.73 -5.43 6.07
1 B1133 248 -4.33 -14.73 -3.30 6.07
1 C2649 248 -4.33 -14.73 -3.25 6.07
2 A0345 2404 -1.44 -6.38 -1.34 3.51
2 B2002 2401 -1.44 -6.38 -1.07 3.51
2 C4612 2402 -1.44 -6.38 -2.14 3.51
3 A4947 5778 -0.72 -3.94 -0.97 2.49
3 B4346 5777 -0.72 -3.94 -0.71 2.49
3 C0210 5777 -0.72 -3.94 -0.74 2.49
   
Study 2, 2004 (Nov - Dec)  
1 A1710 166 -4.85 -21.37 -3.96 11.66
1 B0433 166 -4.85 -21.37 -3.48 11.66
1 C4415 180 -4.85 -21.37 -4.10 11.66
2 A5527 1835 -2.08 -8.96 -2.20 4.80
2 B3440 1835 -2.08 -8.96 -2.42 4.80
2 C1907 1836 -2.08 -8.96 -2.11 4.80
3 A4514 8802 -0.91 -4.25 -1.26 2.43
3 B5317 8801 -0.91 -4.25 -1.42 2.43
3 C2431 6601 -0.91 -4.25 -0.91 2.43
   
Study 1, 2005 (May - Jul)  
1 A5451 401 -2.84 -10.41 -2.94 4.73
1 B5647 402 -2.84 -10.41 -2.83 4.73
1 C4012 482 -2.84 -10.41 -3.06 4.73
2 A1463 1200 -3.44 -12.11 -1.77 5.22
2 B2267 1202 -3.44 -12.11 6.81 5.22
2 C6652 1602 -3.44 -12.11 -1.49 5.22
3 A1467 9003 -1.89 -6.68 -1.66 2.90
3 B7263 9003 -1.89 -6.68 -0.51 2.90
3 C6959 9004 -1.89 -6.68 -1.86 2.90
   
Study 2, 2005 (Nov - Dec)  
   
Due to impacts of Hurricane Katrina, the Louisiana laboratory did not participate in the study.  
   
Study 1, 2006 (May - Jun)  
1 A1333 187 -3.20 -11.20 -0.99 4.70
1 B3557 187 -3.20 -11.20 -1.15 4.70
1 C2740 187 -3.20 -11.20 -1.74 4.70
2 A5874 2400 -1.10 -5.20 -0.76 3.00
2 B0945 2400 -1.10 -5.20 -0.68 3.00
2 C6222 2400 -1.10 -5.20 -0.81 3.00
3 A1519 9800 -1.80 -6.90 -1.23 3.30
3 B7481 9800 -1.80 -6.90 -0.92 3.30
3 C3747 9800 -1.80 -6.90 -0.82 3.30
   
Study 2, 2006 (Oct - Nov)  
1 A3951 161 -3.20 -16.20 15.37 9.90
1 B8059 161 -3.20 -16.20 10.43 9.90
1 C7323 161 -3.20 -16.20 10.26 9.90
2 A6267 1545 -1.30 -6.00 0.20 3.50
2 B5442 1545 -1.30 -6.00 0.11 3.50
2 C4959 1545 -1.30 -6.00 0.49 3.50
3 A5380 10333 -0.50 -3.60 0.08 2.70
3 B8301 10333 -0.50 -3.60 0.25 2.70
3 C7742 10333 -0.50 -3.60 0.13 2.70
   
Study 1, 2007 (Apr - May)  
   
1 A0547 200 -5.20 -21.46 22.11 11.09
1 B3927 200 -5.20 -21.46 20.30 11.09
1 C5256 200 -5.20 -21.46 17.44 11.09
2 A1473 3983 -1.49 -4.57 0.34 1.60
2 B0741 3983 -1.49 -4.57 0.08 1.60
2 C4823 3983 -1.49 -4.57 0.19 1.60
3 A7347 10075 -1.35 -4.69 -0.47 2.00
3 B3834 10075 -1.35 -4.69 -0.54 2.00
3 C6870 10075 -1.35 -4.69 -0.62 2.00
   
Study 2, 2007 (Nov - Dec)  
   
1 A5020 138 -6.19 -22.16 -8.33 9.77
1 B1170 138 -6.19 -22.16 27.41 9.77
1 C7566 138 -6.19 -22.16 -5.90 9.77
2 A4260 1249 -2.17 -7.93 -1.60 3.59
2 B2753 1249 -2.17 -7.93 -1.57 3.59
2 C0845 1249 -2.17 -7.93 -2.34 3.59
3 A5314 10362 -1.20 -4.47 -1.13 2.08
3 B4358 10362 -1.20 -4.47 -0.53 2.08
3 C0273 10362 -1.20 -4.47 -0.57 2.08
   
Study 1, 2008 (May - Jun)  
   
1 A2604 116 -6.86 -20.14 -5.71 6.42
1 B6024 116 -6.86 -20.14 -6.99 6.42
1 C5337 116 -6.86 -20.14 -5.57 6.42
2 A3405 1022 -2.07 -7.31 -2.22 3.18
2 B4629 1022 -2.07 -7.31 -1.74 3.18
2 C5447 1022 -2.07 -7.31 -1.36 3.18
3 A2253 10862 -1.21 -3.72 -1.57 1.31
3 B3774 10862 -1.21 -3.72 -1.25 1.31
3 C6122 10862 -1.21 -3.72 -1.02 1.31
LA Sand Separation LA Fine Separation LA Sediment Mass Results