CWA Consulting ServicesEPA Proposes Alternate Oil and Grease Method for Comment
I read this notice in the Federal Register this morning:
Federal Register Volume 76, Number 240 (Wednesday, December 14, 2011). Proposed Rules. Pages 77742-77747. 40 CFR Part 136. Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act; Analysis and Sampling Procedures;Notice of Data Availability. You can download a copy: http://www.POTW.com/newsandmeetings.htm
The comment period closes January 13, 2012. EPA is deciding whether or not to promulgate this new method (it would have been nice to provide a link to the method for download for free). EPA lists four areas (but you should consider more) that they are requesting comment on:
1. Whether EPA should reconsider promulgating this additional method for oil and grease based on different extractants and determinative techniques than EPA Method 1664A.
2. EPA's current view, based on the data it has reviewed to date, that ASTM D7575-10 is an acceptable choice for the determination of oil and grease for the range (5 to 200 mg/L) evaluated.
3. EPA's current conclusion that permit limit adjustment based on side-by-side comparisons of EPA Method 1664A and ASTM D7575-10 is not appropriate. EPA is particularly interested in obtaining comments from permitting authorities on this issue and estimates of the burden associated with reviewing such requests.
4. If EPA were to allow a side-by-side comparison with limit adjustment as necessary, should EPA look to the approach used for n-hexane in place of Freon (see section III.C above) or should EPA consider a different approach?
Anytime I see something that deals with oil and grease, I tend to get interested on how it relates to the Pretreatment Program. This is one of those times. EPA appears to be reconsidering approval of this method. It is hexane-free (that is good). The working range is stated as 5-200 mg/L. That would limit this method's application when it comes to many food processors and restaurants since their discharges may reasonably be expected to exceed 200 mg/L on occasion. I did do an Internet search and found presentations by the company that is pushing this method approval. One talk that provided data on multiple laboratories can be found here:http://www.pnscta.org/files/2010/2010presentations/08 New FOG, Bill Telliard.pdf
The study showed that POTW wastewater (influent of effluent?) was used in the study. The true value of 10 mg/L oil and grease reported was far from the 200 mg/L that EPA says should be approved. For the POTW (again, was this influent of effluent?), the results had a standard deviation of approximately 16-20%, the worst of all the matrices presented. Also spike recoveries for the POTW wastewater were the worst. As a note: another slide showed that the method achieved 92% recovery as compared to the existing Method 1664 but they type of POTW wastewater was not presented.
EPA presents an interesting rationale for decision-making in this notice (this is not a proposed rule). I do appreciate the request for input based upon EPA's statement: "EPA is soliciting comment only on EPA's consideration of this method."
My initial comments are:
1. Provide a link on EPA's website to the method and allow for download of the method at no cost.
2. Provide a link to all of the data referenced in the Federal Register notice (see end of notice).
3. The data found on the Internet indicate only one POTW wastewater (influent or effluent?) with a true oil and grease value of 10 mg/L was tested. Based upon this, EPA appears to be saying the Agency believes the method is equivalent to Method 1664. This assumption would appear to be unsupported based upon information found on the Internet from the company that developed the method: Oil and grease samples of POTW influent and effluent should be tested. These samples should include multiple oil and grease true concentrations in the 5 mg/L to 200 mg/L range. These sample should be sent to multiple independent wastewater laboratories. EPA seems to be indicating that based upon the data it reviewed (not provided in this Notice), this method is approved for use under the Clean Water Act. EPA needs to do a more thorough public notice of the data it reviewed (provide the data) to make a decision that this method is equivalent to Method 1664 for raw and final wastewaters approved under 40 CFR Part 136.
4. Does EPA believe this method is only appropriate when the actual concentration of oil and grease never exceeds 200 mg/L.
5. Does EPA believe this method is only appropriate for POTW effluents (post treatment wastewaters)?
6. POTWs will have to specify the appropriate method for their permitted users and others (e.g, restaurants, automotive serving, etc.) based upon historical concentrations of oil and grease.
7. Does EPA believe that this approach to method validation and the apparent lack of data on a significant matrix (POTW wastewater) is appropriate to support approval of an alternate, enforceable method under the Clean Water Act?
I hope you get a chance to download and read this Notice. Comment if you decide to. These are the kind of items that all pretreatment professionals should think about. These are my initial thoughts. I have to think about this further. I always review proposals in this order: Legal, technically factual, scientifically valid, implementable, enforceable.
I am not a methods expert but I am a pretreatment program expert and believe that I can read something and evaluate it for reasonableness. So, for all the lab and methods experts out there: Educate me
Curt McCormick, CWACS, Curt@POTW.com, www.POTW.com
Categories: Permits-Permitting, NPDES Permits, National Interest, FOG
Comment to EPA: For SIUs that have to monitor oil and grease for a Categorical Standard, shouldn't comparison data be included with Method 1664 for these specific wastewaters? If this is an alternate method under Part 136, this seems like a requirement.