EPA Method 3511 Caught On (Sorta)
Just recently, I did an internet search for EPA Method 3511 to see if there was any buzz about the method. 3511 is a microextraction method for water samples developed by META with support from EPRI and its member utilities. The validation report was submitted to EPA Office of Solid Waste in 1997 and after much back and forth, the method was added to SW-846 in 2002. But by 1997, META had been using the method for MAHs, PAHs, chlorinated phenols, GRO/DRO, VOCs/SVOCs, PCBs, and almost anything else.
The internet search revealed that 3511 is being used by several laboratories routinely, but mostly just for PAHs or DRO. Most labs are not taking advantage of one of the most important capabilities of the method, i.e., the simultaneous extraction and analysis of volatile and semivolatile compounds. One lab's website recently listed the following as the advantages of 3511:
No impact on reporting limits between EPA Method 3511 and traditional large volume extraction methods;
Less overall time/labor required during field sampling resulting in lower costs;
95% reduction in solvent usage;
Reduction in the total amount of sample water that will be disposed of or treated/recycled;
Less consumables (e.g., uses 40-mL VOA vials versus 1-L amber glass bottles);
Lower risk of bottle breakage during shipping;
Reduced shipping costs
All of these are true, but what about the potentially expanded analyte list?
Here is a timeline for the development of EPA 3511 (and EPA 3570, the sister method for soil):
It is clear that during development, one of the important objectives was to eliminate the need for a separate VOC analysis when analyzing petroleum and coal tar impacted soil and water where the very light EPA target compounds in Method 8260 are rarely found.
What is the source of headwinds?
In our experience, the major sources of headwinds to the use of MSE methods are two-fold. The first is resistance by state regulators and certifying bodies to accept the data because they don't understand the full capabilities of solvent extractions and modern GCs & GC/MSs. The second is resistance by laboratory directors and analysts because they don't understand those capabilities. I urge anyone in our business with MSE experience to push your lab staff and your regulators to use EPA 3511. Generate some verification data and show it around. It's good for the environment; it's good business; and it's good data.
Why is all of this important to consultants and clients?
Some of the value to clients is summarized in the bullet points above.
Also, ever get lab results back and the naphthalene concentration by 8260 is totally different than the naphthalene concentration by 8270? Problem solved with 3511. Ever go to sample a well or sump, and you can only recover a few milliliters of material? Problem solved with 3511. Ever wish the lab could turn around a batch of samples more quickly? Problem solved with 3511. And more.
What about soil?
Analytically, soil is more difficult, but EPA 3570 does a comparable job to other EPA sample preparation methods with all the advantages listed above for water samples. Look for a discussion in a future blog.