Table 7.

Predicted annual percentage contribution (%) from septic tanks to the study area OP budget

Study area OP budgetSeptic tank OP loading contributions (%)
Septic tank discharge (unattenuated)PIT OP loading*Individual assessment (attenuated)
Loading (kg a−1)Source134.1 kg a−144.7 kg a−15.6 kg a−11.04 kg a−10.52 kg a−1
221OP loading leaving study area60.720.
378OP loading leaving study area35.511.
453PIT prediction (HOST Class 1)
488PIT prediction (HOST Class 5)
  • * In this assessment, OP has been extracted from PIT to make these quantities comparable with the other assessments presented in this table.