From Conflict to Sustainable Development From Conflict to ...

Protecting drinking water wells from oil contamination
In addition to the spillage of large quantities of oil caused by the 1999 conflict, Novi Sad oil
refinery has been a source of longer-term and ongoing pollution. Consequently, the entire
refinery area was considered a potential source from which contamination could migrate. As
the refinery is constructed on back-filled sand, spilled oil easily reaches the shallow groundwater
table. Because the Ratno Ostrvo wells are located downstream, in the vicinity of the refinery,
immediate measures for protecting the wells were seen as Novi Sad’s highest priority.
Protection of groundw
roundwater resources at
Ratno Ostrvo
Handover of the hydr
ydraulic barrier to the
Municipality of Novi Sad
Working in close cooperation with Novi Sad Waterworks, UNEP applied a precautionary
approach and immediately initiated construction of a hydraulic barrier to prevent the migration
of contaminated groundwater from the refinery area towards the drinking-water wells.
Work on this project started in mid-2001 and the completed barrier was handed over to the
authorities of Novi Sad in April 2002. Since then, Novi Sad Waterworks has tested the
equipment on a regular basis. Continuous monitoring (see below) has shown that polluted
groundwater has not yet reached the line of the barrier, so its deployment has not so far been
needed. While the Clean-up Programme has therefore successfully implemented an effective
mechanism to prevent contamination of drinking water, additional measures are needed in
the longer term to deal with the actual sources of pollution within the refinery complex.
Since November 2000, monitoring of groundwater quality has been carried out by a partnership
between UNEP, Novi Sad Waterworks, the oil refinery, the University of Novi Sad/
Institute of Chemistry and SDC. The extent of groundwater pollution from spills at Novi Sad
refinery has been determined. The samples collected have not shown any consistent trend of
increasing contaminant concentrations between the refinery and the wells. However, the longterm
risk to the wells has been proven. Ongoing monitoring will provide an early warning of
any imminent threat to the well field and this will trigger operation of the hydraulic barrier.
Hand-over of the monitoring programme to local partners took place in February 2004.
UNEP’S CLEAN-UP PROGRAMME
Repair of main wastewater collector
An approximately two-kilometre long, buried concrete collector conveys wastewater from
the refinery, across the Ratno Ostrvo drinking-water wells, to the Danube. The 1999 air
strikes may have further damaged the collector, which was reportedly in poor condition prior
to the conflict. Severe leakage from the damaged collector has been polluting groundwater
and threatening the nearby wells.
Assessment and Clean-up in Serbia and Montenegro
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