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Use of an old wastewater treatment plant


I work for a NGO which as part of our work does experiential education programs relating to issues faced in developing countries, such as poverty, water quality/scarcity, Aids etc. We need to redevelop part of our site for one of these programs, however the area we want to use is next to an old wastewater treatment plant - unused for around 20 years. Given that the plant likely only served domestic wastewater, should we be concerned about soil contamination? Do we need to get the soil tested for pathogens/contaminants?

Also, there is a well in the area which we want to use which would be great to include in the simulation program but again concerned about water contamination. Even if it's groundwater I am aware that we should implement ongoing water testing if we are going to use the water in the well, but would like to know whether this well might be in anyway have remaining contamination from the wastewater treatment plant.

2 Answers

Elisabeth von Muench

Just to make sure we harness synergies between the two platforms: The same question has been asked on the SuSanA discussion forum and this is the thread with a couple of answers (one from me and one from "bones49"):


If the waste water treatment pant only handled domestic waste water, it is unlikely you will have any problems with contaminants. Given it is 20 years since it was last used, pathogens should not be a problem at all. Some information on the surrounding community and likely users of the plant would be useful in this. Try and find from local authorities if they have any knowledge of what - if any - industrial users may have been connected to the plant. You could also try and find some of the people who operated the plant, as they would also have some idea. For the well, also there should hopefully be no problems, but for that, it would be worth having the water checked. Are you in a totally urban area or peri-urban area? If the latter, possibility of agrochemicals being in the ground water. If the former, any industry in the area which might affect this. Also usual checks for e-coli, ph, salinity etc. should be done. A public health lab will be able to do the latter. For potential chemical contaminants, might be a bit more difficult to find a lab that can test for these but if there is a risk of such contaminants, this should be done.

Having read your more detailed response on the other site, if it was a former army barracks, I would have a high degree of confidence in that it would have been a well run and maintained site, so risk of ground pollution should be fairly low. As well, if it was a completely stand alone system, separated from the surrounding community, I would imagine a low risk of contaminants going into the system to begin with. I would still have the well water checked, at least for basic tests, although since you are in Hong Kong, you will have access to sophisticated labs, so possibly you could look into checking for any other potential contaminants in the water.