WEF Discussion Forums
Laboratory Management and Technical Issues
"solid waste" VS EPA methods
Another question-how does anybody differentiate between a "solid waste" method and an EPA method. We got some results back for a sludge sample (about 2% total solids) and it was run with a solid waste method (SW 6010B). This is not what our other contract lab ran (EPA 200.7), but want to make sure this sounds OK also.
They're all EPA methods. What you're calling "solid waste" methods come from the EPA compendium known as SW-846, which was written by the EPA Office of Solid Waste for work under RCRA. What you're calling "EPA" methods come from the EPA Office of Water for use in NPDES and other general environmental work. Note that the EPA Office of Groundwater & Drinking Water has it's own set of methods, as does the Contract Lab Program for CERCLA/SARA work.
The methods can be very similar, but can have different lists of analytes for which they're approved. Also, the SW-846 methods tend to give analysts more leeway in applying them, i.e. they're written for analytical chemists.
All of that being said, the various EPA offices tend to be INTENSELY jealous of their territories. Thus, if you're doing work under any type of NPDES permit, you should review the methods listed in the tables at 40 CFR 136. (The "okay" drinking water methods are at 40 CFR 141.) You'll find that the tables at 136 also list methods from Standard Methods, ASTM, and USGS, so the EPA isn't totally rigid.
If you're working at a treatment plant lab, you should get a copy of your permit. The allowable TYPE of methods should be in there. For example, we are mandated to use the methods at 40 CFR 136 for domestic and industrial wastewater BUT are required to use SW-846 methods for our biosolids program.
City of Portland, OR