menu ☰
menu ˟

The attenuation of microorganisms in on-site wastewater effluent discharged into highly permeable subsoils

Creator:

GILL, LAURENCE; MISSTEAR, BRUCE; JOHNSTON, PAUL;

Subject Keywords: Environmental and geological engineering; water quality; Ireland; septic tank; E.coli; Smart & Sustainable Planet;
Region:
Description:

An extensive field study on percolation areas receiving both septic tank and secondary treated on-site effluents from single houses in Ireland was carried out to investigate the attenuation capacity of highly permeable subsoils with respect to E.coli bacteria and spiked bacteriophages (MS2, ?X174 and PR772). The development of biomats across the percolation areas receiving the secondary effluent was restricted compared to the percolation area receiving septic tank effluent, promoting a much higher areal hydraulic loading which created significant differences in the potential microbiological loading to groundwater. Greatest E.coli removal in the subsoil occurred within the first 0.35 m of unsaturated subsoil for all effluent types. Analysis showed, however, that more evidence of faecal contamination occurred at depth in the subsoils receiving secondary treated effluents than that receiving septic tank effluent, despite the lower bacterial influent load. All three bacteriophages were reduced to their minimum detection limit (< 10 PFU/mL) at a depth of 0.95 m below the percolation trenches receiving septic tank effluent, although isolated incidences of ?X174 and PR772 were measured below one trench. However again, slightly higher breakthroughs of MS2 and PR772 contamination were detected at the same depth under the trenches receiving secondary treated effluent.

Related: http://dx.doi.org/10.1016/j.jconhyd.2011.12.003
Suggested citation:

GILL, LAURENCE; MISSTEAR, BRUCE; JOHNSTON, PAUL; . () The attenuation of microorganisms in on-site wastewater effluent discharged into highly permeable subsoils [Online]. Available from: http://publichealthwell.ie/node/824484 [Accessed: 23rd October 2019].

  

View your saved citations and reading lists

Contributor:


 
Click here to view all the resources gathered from this organisation's website.