ABSTRACT
A field experiment has been conducted at the Castricum artificial recharge system in the Netherlands. Two types of bacteriophages (MS2 and PRD1) were dosed as model organisms. The water’s flow pattern was first calculated and then verified in 6 monitoring wells. Then sodium chloride was added for 7 days as a tracer. Following this, bacteriophages were added to the artificial recharge water for 11 days. The effectiveness of the soil in removing these micro-organisms was worked out from the levels at which they were present in the monitoring wells. For the test set-up described and for flow through fine dune sand, the experiment indicates an elimination rate for the phages studied of 3 log units in the first 2.5 m; 6 log units for 10 days’ passage through the aquifer (15 m) and 8 log units for 25 days (30 m). Fate and behaviour of human viruses might be explained and understood from these results, so that an artificial recharge system design required for virological reliability can be determined.
