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I’m starting this post with an illustration from one of my recent presentations (click on the image to enlarge it). The quote is from Daniel Kahneman’s book: Thinking, Fast and Slow. It reminds us of how often our perceptions are much more limited than we realize. Let’s turn to the circles to the right of the quote.
In his 1967 book, “The Use of Lateral Thinking” Edward di Bono introduced the concept identified in the book’s title. He contrasted “lateral thinking” against “linear thinking” and argued that successful resolution of any challenge required both types of thinking. What does this have to do with detecting microbes in fuel systems. Standard Practices, such as PEI’s RP900 “Recommended Practices for the Inspection and Maintenance of UST Systems”, are examples of excellent linear thinking. They prescribe a series of steps for performing UST system condition monitoring. Similarly, ASTM D4057 “Practice for Manual Sampling of Petroleum and Petroleum Products” provide a wonderful, linear sequence of steps for collecting fuel samples. Neither of these documents promotes lateral thinking. RP900 is great at detecting component failures once they occur. Similarly, D4057 is great for obtaining samples on which to run tests to determine whether the product is in specification. In contrast, ASTM D7464 “Practice for Manual Sampling of Liquid Fuels, Associated Materials and Fuel System Components for Microbiological Testing” encourages lateral thinking. It encourages users to ask: “what do I intend to do with my sample” and “if I want to detect microbial contamination, what kind of sample do I need to collect; from where should I collect that sample?”
Samples collected per D4057 are unlikely to contain microbes. Consequently, they are not the samples on which it makes any sense to test for microbial contamination. This is the number one reason microbial contamination in fuel systems remains undetected even after the bugs have caused component failure. Microbes need free-water to thrive. Free-water accumulates as condensate on tank surfaces – particularly in the headspace, above product, and on the tank bottom, below product. A substantial volume of free-water is also trapped within slime that accumulates on tank walls. Linear thinking guides us to collecting UST bottom-samples from fill-lines. Lateral thinking helps us to consider alternative sampling points and sample types. If you are interested in learning more about sample collection for microbiological testing, contact me by phone (609.716.0200) or email (fredp@biodeterioration-control.com). In my next blog post, I’ll discuss microbiological test methods.
When I ask petroleum retailers if they have microbial problems in their fuel systems, almost always, the answer is: “No!”. After reading EPA’s recent report – Investigation of Corrosion Influencing Factors in Underground Storage Tanks with Ultra Low Sulfur Diesel Service – I felt better; sort of. The report’s Executive Summary states: “We observed 83 percent of the inspected tanks had moderate or severe metal corrosion. Prior to our research inspections, less than 25 percent of owners reported knowledge of corrosion in their UST systems.” It also observes: “Our research suggests that MIC is likely involved in the moderate or severe internal corrosion in USTs storing diesel.” For the uninitiated, MIC stands for “microbiologically influenced corrosion”.
Now think about this. Regardless of whether UST were fiber-reinforced polymer (FRP) or steel, the vast majority of UST tested had moderate to severe corrosion. Yet only 25% of site owners were aware of the problem. How is this possible? Perhaps we find one explanation in two, September 2016 PMAA Journal articles. Both report how PMAA leadership convinced the U.S. EPA to roll back their initial full set of routine system inspection items that were to be required under the 2015 revisions to the UST Regulations (40 CFR part 280). Interestingly, both articles focus only on the apparent savings site owners will realize. Neither article mentions that the repair and site remediation costs associated with fuel system leaks or failures: $250,000 to $500,000. Note that these estimates do not include revenues lost during site repair. Now let’s consider how many years of more thorough site inspection and condition monitoring one could get for a system failure that only cost $250,000. The PMAA Journal articles suggest a savings of approximately $4000/year/site. That translates into >62 years of more thorough condition monitoring that would reduce the risk of failure substantially. I think that it is particularly noteworthy that the PMAA Journal articles indicate that “PMAA is helping to revise the Petroleum Equipment Institute’s RP-900” in order to reduce the thoroughness and frequency of the walk through inspections detailed in RP-900. Is this a penny wise, pound foolish strategy? In my next post, I’ll discuss the problems with current fuel retail condition monitoring programs. Spoiler alert: I won’t be arguing that they are too burdensome or expensive.
ASTM E2694, Method for Measurement of Adenosine Triphosphate in Water-Miscible Metalworking Fluids, was first approved in 2009. The 2016 revision of the method has just been published by ASTM (www.astm.org). This version includes a new Appendix X4 that provides a protocol for differentiating between bacterial and fungal contamination in metalworking fluids. I had first written about this protocol here in my 04 May 2015 blog. The original research on which the ASTM E2694 revision was based was published in 2014: Passman, F.J. and Küenzi, P., “A Differential Adenosine Triphosphate Test Method for Differentiating between Bacterial and Fungal Contamination in Water-Miscible Metalworking Fluids” International Biodeterioration & Biodegradation (2014), http://dx.doi.org/10.1016/j.ibiod.2015.01.006 0964-8305.
Appendix X4 is meant to be used only on samples that have high cATP concentrations as determined by the basic E2694 test. I generally consider ≥1,000 pg/mL to be high cATP, but others might choose to be more conservative. The differential method guides microbicide selection. If the ATP-biomass is all from bacteria, then a tankside addition of bactericide is generally the appropriate treatment. If it is from fungi, then a fungicide will be needed. A broad-spectrum microbicide or compatible bactericide and fungicide are needed to control an infection that is due to a combination of bacteria and fungi. For more information, contact me at 609.716.0200 or fredp@biodeterioration-control.com.
I’ve recently had the privilege of co-authoring a paper with Dr. Griselle Montenaz, and others, on the use of LuminUltra Technology Ltd’s QGO-M test method to screen aqueous polymer emulsions (APE) for microbial contamination. The paper describing the use of QGO-M XL measuring cellular adenosine triphosphate (cATP) in aqueous polymer emulsions (APE) has just been published in the journal: International Biodeterioration and Biodegradation (IBB; 114 (2016) 216-221; doi:10.1016/j.ibiod.2016.06.007). The procedure reported in the IBB paper reduces the time delay for microbiological contamination testing from the typical three to five days required for culture testing to less than 10 minutes. Currently, the cost of holding APE in quarantine while waiting for a microbiological clean rating is estimated to be in the hundreds of thousand dollars per year range for a single manufacturing facility. Additionally, the costs associated with spoiled APE batches can range from $50,000 to $250,000 per incident. The QGO-M XL method described in this paper essentially eliminates quarantine inventory time and increases the reliability of microbiological contamination testing..
The multi-year investigation was a collaborative effort of researchers at the Advanced Polymer Technology team at The Dow Chemical Company, Biodeterioration Control Associates, Inc., and LuminUltra Technologies, Ltd. Initial evaluations were run using a variety of APE that had been spiked with microbes that are known to be problematic to APE. In these studies, cATP concentrations were compared with culture test results. Successful detection and quantification of microbial contamination in laboratory samples set the stage for the second phase of the research effort. A total of 88 APE production run samples, including representative samples of 14 different types of APE, produced at 16 different production plants, were tested by QGO-M XL and standard plate count (SPC).
The traditional upper control limit for microbiological contamination in APE is ≤1,000 CFU mL-1. The investigation demonstrated that QGO-M XL’s sensitivity was substantially greater than that of the SPC method. The QGO-M LX test detected ≥100 cells mL-1 (»0.1 CFU mL-1), while the SPC protocol detected ≥10 CFU mL-1). Consequently, QGO-M XL provided more data about actual bioburdens in samples with ≤10 CFU mL-1. This additional information drives process improvement that reduces the risk of APE either being produced or shipped with unacceptably high microbial contamination. Additionally, because QGO-M XL can be run in the lab or in the field, the test can be used to identify microbial contamination sources after APE has been shipped. This improves APE product quality control for producers, transporters and users. The improved quality control has already translated into substantial cost savings for stakeholders who have adopted QGO-M XL for APE microbial quality control testing. For more information, contact me at fredp@biodeterioration-control.com.
The US EPA has just released a report of the results of a series of 42 UST inspections that were performed in January and February 2015. Despite the tiny percentage of ULSD UST inspected and sampled, the report highlights the considerable disconnect between observed corrosion (83% of the systems inspected had moderate to severe corrosion) and corrosion awareness (only 25% of site owners were aware of corrosion issues. The report also does a nice job of listing the different ways in which uncontrolled corrosion – particularly microbiologically influenced corrosion (MIC) – can increase operational costs and decrease profitability.
The investigators were able to collect bottoms-water (B-W) samples from only 11 of the 42 inspected UST. The pH of those B-W samples averaged 4.6, which is in the acidic range (neutral pH = 7.0). Moreover, many of the B-W samples contained mixtures of weak organic acids that are characteristic of microbiological activity. Unfortunately, no microbiological testing was included in the study.
The report’s greatest value is in its potential to improve awareness. I recommend that all fuel retail site owners and operators read at least the executive summary. You can find the EPA report at https://www.epa.gov/ust/alternative-fuels-and-underground-storage-tanks-usts#tab-5.
BCA’s Microbial Audit program is unique within the petroleum industry. It provides the total picture of both current and potential MIC risk. For more information visit the Microbiological Audit’s section of BCA’s Services listing (https://biodeterioration-control.com/microbial-testing-services/).
The US EPA’s Office of Underground Storage Tanks has just published a clear and concise document on UST release (leak) detection (https://www.epa.gov/ust/release-detection-underground-storage-tanks-and-piping-straight-talk-tanks). Coincidently, in the past few days, my friend Walt Huysman posted a LinkedIn blog about predictive maintenance (PdM). What’s the connection? UST release detection effectively signals the need to take immediate corrective action. UST replacement and site remediation can easily cost $250,000 to $500,000. PdM is designed to strike a high return on investment (ROI) balance between the costs associated with condition monitoring and preventive maintenance actions, on one hand, and corrective maintenance actions, on the other. Assuming a well-designed and managed program, PdM typically costs a tiny fraction (<1%) of corrective maintenance costs. Microbiologically influenced corrosion (MIC) has been estimated to be responsible for as much as 50% of the economic damage caused to petroleum infrastructure. However, neither the US EPA UST Regulations nor PEI’s RP-900 (UST Inspection and Maintenance) include guidance on PdM for microbial contamination. PdM to include microbial contamination monitoring and control is a high ROI proposition. Prevention of product release is only the tip of the iceberg. To learn more, contact me at fredp@biodeterioration-control.com.
How many of you recall the Bob Seeger song: Where have all the flowers gone? It seems that it might be time to modify the lyrics by replacing the word flowers with biocides approved for use in metalworking fluids (MWF). I admit, that’s a mouthful, but the reality is comparable to that behind the original song. The list of active substances for which Biocidal Products Regulation (BPR) dossiers have been submitted includes a mere 27 actives intended for use in MWF. Less than 10 years ago, there were more than 100 options. The dust hasn’t yet settled in the USA, but once the US EPA’s Office of Pesticides Programs rules on the maximum permissible dosage of triazine in MWF later this year, it’s likely that the ASTM E2169, Table 2 list of active ingredients approved for use in MWF will be a fraction of its original length. Perhaps, when compared with our European friends, we are still lucky in the USA. A literal reading of the BPR’s definition of a Biocidal Product suggests that all MWF are Biocidal Products. The UEIL is advocating that MWF be formally recognized as Treated Products (the cost impact is an estimated $250,000 U.S. per MWF formulation – not trivial). Regulators have promised to give UEIL’s arguments full consideration, but nothing has yet been put in writing. I reviewed the latest state of affairs in my January 2016 TAE presentation. Please contact me if you are interested in receiving a copy of the manuscript: Impact of Biocidal Product Regulation on Microbial Contamination Control in Metalworking Fluids.
If you will be attending the STLE Annual Meeting on 15 through 19 May 2016, be sure to join me at the Metalworking Fluids Technical Session III, in the Silver Room, Bally’s Las Vegas, NV. At 0830h, on Tuesday 17 May, I’ll be presenting my paper: “Adenosine Triphosphate Testing to Evaluate Biofilm Dispersants.” The paper discusses the use of LuminUltra Technologies Limited’s QGO-M and DSA test methods to compare the efficacy of a number of different formulations for removing biofilm from pipe surfaces without being biocidal. As regulators increasingly restrict the use of MWF microbicides, it is becoming increasingly important to develop non-biocidal biodeterioration prevention strategies. My STLE presentation will speak directly to this issue. I’m looking forward to seeing you in Las Vegas. Please contact me directly (see “REQUEST INFORMATION” on BCA’s home page) if you would like to schedule a conversation during the STLE Annual Meeting.
For those of you who are interested in metalworking fluid microbiology and microbial contamination control, I invite you to read my March 2016 Tribology and Lubrication Transactions TLT) article: MWF Biocides Part II – Science vs. Fiction.
This was an accidental article that I was asked to write in response to an error-laden article that had appeared in TLT’s November issue. The earlier piece had been written by an individual whose familiarity with the topic was limited to the research performed in the process of drafting the TLT submission. I had not yet read the article when I started receiving flaming emails from industry colleagues who mistakenly believed that I had an editorial role and had somehow approved the article for publication. Initially, my plan was to write a letter to the editor. Indeed, I wrote a draft letter listing each error and the correct information (with relevant references cited as appropriate). The letter morphed into the March article. To be sure that I wasn’t just offering my personal opinions, I recruited log time colleagues Drs. Neil Canter and Alan Eachus and Mssrs. Jerry Byers and Richard Rotherham to co-author the article. I am much indebted to each of them for their contributions to the effort.
MWF Biocides Part II focuses primarily on the scientifically unsupportable conflation of formaldehyde (HCHO) and formaldehyde-condensate microbicides (FCM). The toxicological profiles of FCM differ among specific chemistries, but as a group are substantially different from HCHO. Moreover, although regulators assume that 100% of the HCHO in FCM will end up in the air above metalworking fluids (MWF) threated with FCM, data prove otherwise. Over the past couple of years, the number of microbicides approved for use in MWF has plummeted. In Europe there are only 27 listed biocidal substances (most are still going through regulatory review) that can be used in MWF. In the U.S., by last summer, the US EPA’s Office of Pesticides Programs will most likely issue guidance that will determine the future availability of FCM. In addition to clarifying the FCM issues that had been misreported in the November article, the March article sets the record straight on nearly 30 other misstatements made in the earlier publication.
Please contact me at fredp@biodeterioraiton-control.com for a copy of the MWF Biocides Part II.
