Better option available for sewage treatment

A small number of tertiary, decentralized treatment plants will cost less than a centralized plant

In his letter of Jan. 14, Jack Hull tries to illustrate my lack of expertise in sewage treatment by asserting that activated sludge treatment is at the core of membrane bioreactor tertiary treatment plants (MBR), as if I did not know that. I as all the RITE plan supporters know, both secondary and tertiary treatment plants use the activated sludge treatment – ie. growing bacteria as the basis of biological treatment, however what sets them apart is the MBR membrane filtration, where the solids, bugs, superbugs, micro plastics and micro fibres are separated from the liquid and this very fine filter (0.04 micron) is missing in the secondary treatment, therefore producing dirty effluent that contains all the bad things that go into the sludge in the secondary treatment process. Furthermore, anaerobic digestion would not remove all these materials from the biosolids produced, whereas gasification would.

It seems that Mr. Hull erroneously talks about contaminant removal with ultraviolet light disinfection at the secondary treatment plant, while an educated amateur like me knows that ultraviolet lights can be used for disinfection with much less efficiency with secondary effluent because high level of suspended solids will muck up the UV lamps. UV or ozone disinfection in secondary treated effluent will not remove heavy metals, dissolved toxins, pharmaceuticals, micro plastics, micro fibres etc. that the secondary system will discharge into the ocean.

I am a biochemist with experience in microbiology while many other relevant professionals including planners, engineers, economists, educators, entrepreneurs, etc., are also involved. We advocate for inclusive public consultation, technical innovation and full life cycle analysis on behalf of concerned members of the public that have been ignored by the CRD. Mr. Hull has been in bureaucratic positions for many years repeating from reports prepared by others. Does that make him more qualified?

Mr. Hull and I again differ on the costs, which I believe will be lower than what he proposed for the now defunct centralized secondary treatment plan based at McLoughlin Point. He fails to acknowledge that recent advances in membrane technology and MBR systems have resulted in significantly increased membrane flux capacity and decreased energy consumption and that gasifiers are much less expensive than anaerobic digesters. Furthermore, if we don’t have to build 18 km of pipelines to pump the sludge to Hartland, anaerobic digestion facilities, massive pump stations, conveyance tunnels and new deep sea outfalls, the total costs of the entire project will go way down.

Mr. Hull further insults the RITE plan advocates as a group of well-meaning but unqualified members of the public that refuse to reveal the data on the costs of building smaller, decentralized tertiary treatment plants. He never contacted me for this information. Instead, he derides the RITE plan by stating that enormous additional costs will be incurred for a reclaimed water pipe network and plumbing retrofits, thinking that this is the only solution for a tertiary system when in fact there are several other low cost options. This seems to be a case of him not seeing the forest when looking only at one tree.

In summary, a small number of tertiary, decentralized treatment plants and 1-2 gasifiers will in my opinion cost about 300 million dollars less than Mr. Hull’s billion dollar boondoggle plan and provide cleaner, toxin and pathogen free effluent, which is the actual reason why the government mandated us to stop polluting the environment and build sewage treatment plants.

Thomas Maler

Victoria