Lead in Soils at the EWU Palouse Prairie Restoration Site
Faculty Mentor
Carmen Nezat
Document Type
Poster
Start Date
10-5-2023 11:15 AM
End Date
10-5-2023 1:00 PM
Location
PUB NCR
Department
Environmental Science
Abstract
In the 1960’s, EWU acquired a parcel of wheat farmland directly behind its campus. The land has mainly been used as farmland, but trapshooting occurred during the 1980s and again in the early 2000s. The land is now set to be restored into its native Palouse Prairie ecosystem in conjunction with public walking trails. Several student research projects have tested the elemental concentrations of the soil using a 1M nitric acid leach and found elevated lead concentrations corresponding with the trapshooting ranges. Eight samples were selected from the pool of previously collected soils for reanalysis, six selected with lead concentration of over 130 mg/kg, and two which have presumed background lead concentrations. These soils were digested in concentrated nitric acid using a microwave digestion system to provide a total lead analysis and to comply with EPA testing standards for soil analysis. Preliminary results indicate that the 1M HNO3 leach removed about 80% of the total soil lead (the portion removed by the high temperature, concentrated nitric acid digest). The lead in some soils (30 to 500 mg/kg) were higher than the background concentrations in non-trapshooting areas (7 to 10 mg/kg). Because some areas in the prairie exceed the EPA guideline for child play areas (400 mg/kg), delineation of areas with elevated lead concentrations encourages further investigation.
Recommended Citation
Dodson, Rae, "Lead in Soils at the EWU Palouse Prairie Restoration Site" (2023). 2023 Symposium. 17.
https://dc.ewu.edu/srcw_2023/res_2023/p2_2023/17
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Lead in Soils at the EWU Palouse Prairie Restoration Site
PUB NCR
In the 1960’s, EWU acquired a parcel of wheat farmland directly behind its campus. The land has mainly been used as farmland, but trapshooting occurred during the 1980s and again in the early 2000s. The land is now set to be restored into its native Palouse Prairie ecosystem in conjunction with public walking trails. Several student research projects have tested the elemental concentrations of the soil using a 1M nitric acid leach and found elevated lead concentrations corresponding with the trapshooting ranges. Eight samples were selected from the pool of previously collected soils for reanalysis, six selected with lead concentration of over 130 mg/kg, and two which have presumed background lead concentrations. These soils were digested in concentrated nitric acid using a microwave digestion system to provide a total lead analysis and to comply with EPA testing standards for soil analysis. Preliminary results indicate that the 1M HNO3 leach removed about 80% of the total soil lead (the portion removed by the high temperature, concentrated nitric acid digest). The lead in some soils (30 to 500 mg/kg) were higher than the background concentrations in non-trapshooting areas (7 to 10 mg/kg). Because some areas in the prairie exceed the EPA guideline for child play areas (400 mg/kg), delineation of areas with elevated lead concentrations encourages further investigation.
