Analyzing Total Suspended Solids in the West Run Water Shed using method SM2540B

Samantha Williams* (1,2), Jason A. Hubbart (1,2), and Susan Hickman (2)

1 Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV, 26506 

2 Institute of Water Security and Science, West Virginia University, Morgantown, WV, 26506

Presentation Category: Agricultural & Environmental Sciences (Poster Presentation #62)

Student’s Major: Environmental, Soil, and Water Sciences

Accurate estimates of Total Suspended Solids are important for receiving water assessments and watershed management and planning. However, differences in results between practitioners can be substantial but is often not assessed. Unchecked, these differences could lead to substantial error in land management decisions. To assess differences between personnel performing the exact same test, two replicates (SW and SH) of each of twenty-two monitoring sites (from the same sub-sample of water) were analyzed for total suspended sediment (TSS) using the National Environmental Methods Index method SM2540B. Each water sample was filtered using a vacuum pump system. The filters were dried in in the oven until samples remained within 4% or 0.5 mg mass change over time. Samples were cooled and weighed. Results indicated substantial differences between analysis results for different individuals. For example, the average TSS was 18.8 mg/L and 14.3 mg/L for SW and SH, respectively, a 31% difference. Maximum TSS was 102.0 mg/L and 93.0 mg/L, for SW and SH respectively, a 9.6% difference. Standard deviation was 25.15 and 21.41 for SW and SH, respectively, or a 17.5% difference. Collectively, study results indicate a large difference between individuals conducting this analysis, that could result in a great deal of error (depending on where the error lies) and incorrect evaluation(s) of results. This work emphasizes the need to be sure that practitioners are well trained, using identical methods, and making sure that results are statistically comparable.

Funding: National Science Foundation

Program/mechanism supporting research/creative efforts: a WVU 297-level course, Federal Work Study