Package Plants – are they fit for purpose?
Compliance in the wastewater treatment industry
Our long history of compliance strategy within the wastewater treatment industry has shown some very conflicting outcomes. The main concern has always been the regulatory town councils and, of course the government authorities, both often being at odds with each other.
Once we had built and installed our first package plant, down in Drummond – KZN - on the late John Bizzel’s smallholding we have been pressured to test the system. When the plant was in, and running, Durban Metro insisted we perform 12 weekly water analysis tests – noting that the already endorsed products had been pre-approved without even a sniff from head of Water and Sanitation, Neil McCleod.
Our first attempt was thwarted by Durban Metro (DM), after we were already in our 5th week of weekly tests by Talbot and Talbot Laboratories - DM had not been informed at the start. While this set us back, we were getting some really good water quality results. For three weeks DM were also getting good results from their lab.
In the meantime, Umgeni Water, offered to test our plant, and they themselves found full compliance. Scarab achieved special standards on key indices. In comparative tests on two other sewage systems, Umgeni found that those had hopelessly failed.
We felt that our Scarab system was the most tested plant, and that never has there been any other program for judging plant designs based on water quality alone. After all, this is the purpose of on-site sewage systems, right? Water quality!
Then I recall Umgeni Water, the Water Research Commission (WRC) and Dept of Water and Sanitation (reference here) doing a full 6 month on-site, constant attention research program, in 2005. 3 different plant suppliers were asked to provide a trial system based on their own technologies, and the following technologies were supplied.
- submerged biological contactor (SBC) (this is the most common of all systems available today)
- rotating bio contactor(RBC) (Not a popular technology and you wont find this in your garden)
- sequencing batch reactor (SBR) (based on the activated sludge process, and not a popular technology)
The test program ran from February until September 2005. All systems had the same value of incoming sewage quality, and so there was no quality variation.
Whilst there were initial teething problems on the systems, the RBC and the SBR performed reasonably well. The SBC, on the other hand, did not comply once, logging 198 faults during the test period. So, was this the end of the embarrassing product?
Not at all. It went on for another decade before the wheels started falling off. (see below).
So, how many other products don’t perform as promised? We were offered a design from the UK (as understood) that did not even have disinfection as a standard feature, and would never have passed the local requirements. Then, there was one of those silly little compact, electric free, underground units that offered a compliance certificate signed by the owner of the company. Both these products can now be found on South Africa shelves.
As of this year there are 42 companies selling their own brand of package plants in South Africa, but how many have been independently tested for compliance, prior to product launch and marketing? And how many designs are buried, and therefore compliance cannot be easily checked?