Over the last year, by strange happenstance, I became involved in an investigation of water quality at my school, Environmental Sciences Magnet in Hartford, CT. In the process I learned a bit about the health implications of copper contamination, and a lot about how an institution - Hartford Public Schools - manages an inquiry into a public health issue. On this page, I present some of what I learned, and offer it publicly because I believe that the affected community should have all of the same information held by decision makers. I am not editorializing here, and I have no interest in making people afraid. There are plenty of other environmental issues that actually pose greater dangers. So if we get the solution to this one right, we'll be prepared for the next one. Copper at ESM - a brief chronology In February 2017, students showed me “blue water” from a grade 4 classroom. I tested (Lamotte test tab) and found the sample had approx. 40 parts per million copper*. I was concerned when I looked up the EPA standard, which sets 1.3 ppm as the action level for copper. Further tests by me, and later by the City identified a half dozen other locations with levels over the EPA standard. March - the ESM community was informed of the findings, and for non-compliant taps, custodians were instructed to flush sinks, though they were given no protocol for doing this. Consequently this resulted in cases of no flushing, and in cases of literally thousands of gallons of water run into drains. (The City's and my tests indicated that copper was almost always diminished to below standard in about 1 minute of flushing.) Taps with very high levels were then shut off and later fitted with filters intended to remove copper (see below). School officials said that a remediation plan would be developed and shared with the community (Courant article here). October - I sought information from Facilities regarding follow-up. On one issue, I suggested: A real evaluation of the underlying problem at ESM might be helpful in predicting what other buildings might be at risk ... Before Feb 2017, it might have been reasonable to assume that copper levels were in compliance with the EPA rule. After Feb 2017, knowing that one school (ESM) was far out of compliance, it would be reasonable to assume that this problem is more widespread. In fact, I have my own very limited data for another HPS school, which included a positive copper test. I received no answer to the inquiry. I have submitted a formal request (FOIA). What are the potential effects of high copper concentrations in drinking water? If you want to go straight to an authoritative source, check Copper in School Drinking Water (MA Dept of Public Health). The EPA sets a maximum allowable concentration of 1.3 parts per million for copper in drinking water. What if your water is substantially above that level? It is clear that there are negative (though not usually serious) effects fairly close to the 1.3 ppm standard.
The conservative way to view this would be to consider exposure over the 1.3 ppm EPA standard to be excessive. That said, the exposure in most cases was low - assuming that the contaminated taps in classrooms were infrequently used for drinking. For the science lab kitchen, staff lounge, and LGI, there had to have been considerable exposure, and some cases of (probably mild) illness. The risk of illness goes up with the volume, and the copper concentration. You would be unlikely to experience symptoms from say a cup of water at 3 ppm (classroom B206). A cup of water at 30 ppm (staff lounge) would carry 10 times the dose. A quart of that water would carry 40 times the dose. It is interesting that the "blue water" problem has been around at ESM for a long time. A teacher and a custodian told me that they had noted the discolored water years ago, and so did not drink the water. What is the cause of high copper concentrations? It is unlikely that the issue is the utility's water - MDC reports a maximum copper level of 0.0012 ppm (2016). The cause is almost certainly physical, chemical, or electrical interactions with copper plumbing. In ESM's case, it is difficult (for a non plumber) to ID the problem. But it is notable (and unfortunate) that we have problematic taps in distant locations throughout the building. How can copper contamination be remediated? Flushing taps appears (from my data) to be very effective, as long as users are compliant. Simply turning off taps is certainly effective, though inconvenient. There are reverse osmosis filters that would be effective, though they would probably cost a few hundred dollars apiece. The ideal and permanent solution would be to eliminate the sources of contamination within the plumbing. Are there additional problems? What about lead? Lead contamination would be a much scarier problem. The school has been tested in the past, and levels were determined to be safe. It is also important to note that our copper problem is not suggestive of a lead problem. Because copper and lead are not generally caused by the same water chemistry--they are not generally correlated. However, it may be prudent to re-test for lead, given that our (now) known copper problem could have easily been missed if just a few locations were tested. Lead did show up in 3 New Haven Schools in 2016. Hartford Schools were queried at that time (NBC report), and an administrator indicated that ""We’re definitely are putting a plan together so we can test all our schools." I have requested lead testing data from HPS via a Freedom of Information Act request, and await a reply. * My own colorimetric tests are not definitive or precise. They work like this: if after adding a reagent the solution is orange, I have <1 ppm. If the solution is pure blue, I estimate >4 ppm. And then I can look at intermediate gradations in color. I can also estimate concentrations higher than 4 ppm by making dilutions. If I dilute 1:10 and still obtain dark blue, then I estimate >40 ppm. How do I know that my results are even in the ball park? My reagents are new. I calibrated with known copper standards. I got a >>4ppm result for water that was visibly tinted. And my results were largely confirmed by the City's formal tests. Why are my results higher in some cases than the City's? When water is first drawn from a tap after a period of disuse (a "cold draw"), any plumbing contamination will test high. A period of flushing will reduce the level. If the City's test was run after abundant flushing the night before (which was the protocol), the levels will be lower than if the tap is tested on say, a Monday morning. I don't know the particulars of the City's process because the tech refused to answer my questions.
2 Comments
Avacado
3/6/2018 07:33:44 am
The 4th grade classroom had SO much copper! How can you get rid of the copper? How long will it take?
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DLC
3/7/2018 10:58:07 am
The best way to prevent copper contamination is to remove the contaminated plumbing. But that is expensive. Filters can be installed, also expensive.
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AuthorDavid Cappaert, Resident Scientist, Environmental Sciences Magnet school Entries in order
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