PCB News

Wisconsin state guidance issued for PCBs in land-applied sludge

Environmental Laboratory Washington Report
March 28, 2003

The Wisconsin Department of Natural Resources has issued guidance for the land application of wastewater sludges and biosolids relative to PCBs. The guidance, which is voluntary until regulations are passed that make it mandatory, outlines the maximum average annual application rates, procedures for calculating PCB concentrations and the analytical methods to be used, as well as monitoring frequencies.

For lands used for grazing or food crops, the guidance indicates a maximum of 1,200 mg per acre of PCBs can be applied each year. For all other lands, the maximum average annual application rate is 2,500 mg per acre.

The concentrations are to be determined using Methods 1668 or 8082.

Method 1668 may be used to test for all PCB congeners. If this method is employed, all PCB congeners should be delineated. A number of the congeners will co-elute with others, so there will not be 209 results to sum, the guidance says. However, all results should be added together to enable the reporting of a total PCB dry weight result. Non-detects should be treated as zero, and values between the LOD and the LOQ should be summed using the result.

EPA Method 8082 should be used for PCB-Aroclor analysis and may be used for congener-specific analysis as well. It is up to the discretion of the permit holder to have Aroclor or congener specific analysis performed. If congener specific analysis is performed using Method 8082, the list of congeners tested should include congeners 5, 18, 31, 44, 52, 66, 87, 101, 110, 138, 141, 151, 153, 170, 180, 183, 187 and 206.

For either method, the sample should be extracted using the Soxhlet extraction Method 3540C. In order to remove interference, cleanup steps of the extract are required to achieve the lowest detection limit possible. Experience with these methods shows that an LOD of 0.11 mg/kg should be anticipated for Aroclor analysis in most cases, the guidance says.

If congener specific analysis is done using method 8082, an LOD of 0.003 mg/kg for each congener should be anticipated in most cases. If the anticipated LOD cannot be achieved after using clean up techniques outlined in the guidance, a reporting limit that is achievable for the sample should be determined. This reporting limit should be reported and qualified indicating the presence of an interference.

To view the guidance, go to www.dnr.state.wi.us/org/es/science/lc/download/PCB-Guide.pdf.

Copyright 2003 LRP Publications