NIST completes soil study of reference materials

The National Institute of Standards and Technology (NIST) has issued three new certified reference materials for soil. Intended for use as controls in testing laboratories, the new Standard Reference Materials (SRMs)—gathered from the San Joaquin Valley in California and from sites near Butte and Helena in Montana—will aid in determining soil quality, detecting soil contamination, and monitoring cleanup efforts from accidental spills or atmospheric deposition.

Whether for evaluating soil quality and health, suitability for crop use, assessment of contamination, or for environmental monitoring, analysis of soils are performed routinely by a variety of commercial, government, and university laboratories around the United States and the world. The three new soil SRMs are 2709a, San Joaquin Soil, 2710a, Montana Soil I, and 2711a, Montana Soil II. They come with NIST-certified values for most elements regulated by the Environmental Protection Agency, including those identified as priority pollutants in the Clean Water Act and those specified as hazardous air pollutant elements in the Clean Air Act. NIST created its first batch of sample soils, which the new SRMs replace, about 20 years ago. Efforts to restock the supply with an updated SRM began in 2006.

Scientists at the United States Geological Survey’s (USGS) Denver, Colo., laboratory collected the soil for the new SRMs from either the same or near the same locations as they had collected the original soils. The USGS team then prepared the soil samples by individually drying them, sifting them, and blending them before they were packaged and sent to NIST for further processing.

Using non-destructive methods whenever possible, NIST researchers certified most values for elemental and chemical constituents with two or more analytical techniques. USGS scientists provided additional confirmation of the certified NIST values. Altogether, the team published certified, reference and information values for 44, 48 and 45 elements in SRMs 2709a, 2710a and 2711a respectively.

Source: National Institute of Standards and Technology (NIST)