NIST has issued three new certified reference materials for soil. Intended for use as controls in testing laboratories, the new Standard Reference Materials (SRMs) will aid in determining soil quality, detecting soil contamination, and monitoring cleanup efforts from accidental spills or atmospheric deposition.

The SRMs were gathered from the San Joaquin Valley in California, and from sites near Butte and Helena in Montana. The first batch of sample soils, which the new SRMs replace, were collected from the same areas about 20 years ago. Efforts to restock the supply began in 2006.

Whether for evaluating soil quality and health, suitability for crop use, assessment of contamination, or for environmental monitoring, analyses of soils are performed routinely by a variety of commercial, government, and university laboratories around 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.

Scientists at the United States Geological Survey’s (USGS) Denver, CO, laboratory collected the soil and prepared the 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. The team published certified, reference and information values for 44, 48, and 45 elements in SRMs 2709a, 2710a, and 2711a respectively.

NIST prepares, analyzes, and distributes more than a thousand different materials that are used to check the accuracy of instruments and test procedures used in manufacturing, clinical chemistry, environmental monitoring, electronics, criminal forensics, and many other fields.