|28 February 1979
||Spillage of diesel into Coonjimba Billabong, no reported
|9 November 1979
||Contractor's plant encroached on fenced off vegetation;
area was re-fenced and vegetation restored.
|22 November 1979
||-20L diesel spilled into a drain in Jabiru; spill
was contained and did not enter natural waterways.
|7 December 1979
||Small amount of oil-tar spilled a sediment control
pond at the Jabiru Police Station; no environmental effect.
|23 February 1980
||One tree knocked over by a contractor; no major impact
on general environment.
|29 March 1980
||RUM pumped water from Borrow areas A & B to ponds
2 and 3 before the ponds were declared officially to be RRZ. No
|6 June 1980
||Release of 1000M3 of silty water discharged from
Borrow D to Georgetown Creek, no significant environmental impact.
|week ending 27 June 1980
||Dry drilling in Borrow Pit A; no environmental significance
but wet drilling was to be used under OH&S requirements.
|11 August 1980
||One sea eagle found shot near junction of Magela
and Georgetown creeks; police informed.
|9 November 1980
||One antilopine kangaroo found shot at Gulungul creek
borefield; RUM limited access to the area.
|1980-81 Wet Season
||Sewer at old mess site became surcharged at times
and sewage entered Coonjimba Billabong; RUM undertook remedial works;
no lasting environmental impact
|9 April 1981
||Small volume of water and silt flowed from RUM's
organic dump tank to Georgetown Creek; no contamination in water
and flow failed to reach main channel.
|29 July 1981
||Recycle water tank overflowed spilling process water
from #3 pond into the neutral thickener area. Some of the water
and a minor amount of tailings solids were pumped into the stormwater
collection pond which discharges to #2 pond during the wet season.
The estimated volume pumped was 40 m3 ; no lasting environmental
|31 July 1981
||Fugitive slaked lime dust from a lime transfer operation
blew onto the surface of Djalkmara Billabong and was noted through
a pH reading of 9.3 during routine monitoring. Impact was small
and problem overcome by introducing water spray on lime before and
||During commissioning of the mill process stream waste
rock was used. The ground waste accumulated at one point in the
tailings dam and some was exposed to air. Situation was modified
once true tailings were produced and procedure introduced to move
deposition pie. No environmental impact.
|5 August 1981
||Clarified pregnant liquor tank and associated clarifier
tank overflowed into an adjacent bund due to operator error. Liquor
was pumped back; further overflow stopped by adjustment of process
flow rate; some slight increase in radioactivity in bund during
incident but considered minor.
|13 August 1981
||Sewage manhole at Coonjimba Camp discharged at 3-4
litres/min and effluent was flowing on the track to the billabong;
leak was due to a faulty automatic pump control which prevented
pump starting; repairs effected; no environmental impact.
|3-23 November 1981
||2 islands of tailings appeared in the tailings dam,
area about 20 sq. metres; mine closed for 4 days while authorisation
and requirement for 2m water cover were reviewed. Authorisation
amended to show water cover rather than specific depth. No environmental
|23 November 1981
||Spillage of concentrate from a drum outside the store
during unloading; cleaned up; no environmental impact.
|25 November 1981
||Two observed emissions of concentrate dust from the
scrubber stack, estimated at 2-4 kg uranium. This exceeded the daily
discharge limit of 1.5 kg uranium. Repairs to control system effected
to prevent recurrence; no environmental impact.
|26 November 1981
||Operator found in bare feet whilst working in the
tailings dam; estimated radiation exposure was trivial; operator
and supervisor advised on importance of following safety procedures.
|11 December 1981
||Small amount of tailings leaked from a pipeline to
the tailings dam floor above the water level; covered with soil;
no environmental impact.
|14 December 1981
||Small tailings spill from breather valve in tailings
pipeline on inside perimeter on tailings dam embankment. Breather
valves declared redundant and removed; tailings cleared up into
dam; no environmental impact.
|22 December 1981
||#3 sewage retention pond overflowed. Contractor staff
failed to be on site as required; RUM took over running plant; environmental
impact, following rainfall dilution was very minor.
|28 December 1981
||Operator sprayed with ammonium diuranate, he showered
and was treated at the first aid post; test showed no contamination.
|2 January 1982
||Break in tailings line inside tailings dam wall;
some erosion, wall repaired with waste rock, no environmental impact.
|5 January 1982
||Small quantity of yellowcake spilt from two drums
in transport outside packing area; cleaned up by safety officer;
no environmental impact; new procedures introduced to prevent recurrence.
|22-23 January 1982
||About 40 dead fish were found in Coonjimba Billabong;
Water quality checks showed nothing abnormal; natural fish kills
occur in the area from time to time.
|22 January -
2 February 1982
|Acid plant stack emissions measured to be in excess
of allowable limit of 2kg/tonne of acid produced; problem due to
incorrect fitting in plant since commissioning; part replaced and
level fell to about 1.3 kg/tonne; No lasting environmental impact;
new checking procedure introduced.
|18 February 1982
||Small leak from tailings pipeline detected; line
shut down and repair effected within 1 hour including clean up,
all tailings stayed in the RRZ. No danger to health or environment.
|25 February 1982
||Acid mist eliminators in acid plant flooded due to
blocked drain and mist level exceeded permitted limits; plant shut
down and fault rectified; no environmental impact.
|4 March 1982
||1m square island of tailings appeared above water
in tailings dam overnight when pipe was not shifted on time; corrected
during the next shift; no environmental impact.
|16 March 1982
||SO2 analyser on acid plant damaged by acid; alternative
tests showed emissions below limit; no environmental impact.
|25 March 1982
||Bleeder valve on tailings pipeline leaked a small
amount of tailings onto inside top of embankment; Tailings were
hosed into dam, no environmental impact.
|20 April 1982
||30 m3 pregnant organic liquor solution overflowed
from an overflow sump into stormwater system thence to 32 pond.
Operation was stopped; sump modified to prevent recurrence; no environmental
|16 June 1982
||Emissions on packing area scrubber exceeding allowable
rate; unit was shut down and overhauled; system modified to prevent
blockage in water filter; no environmental impacts.
|22 June 1982
||Filter cake form sulphur meter self ignited and was
not fully extinguished before dumping in tailings dam; subsequently
re-ignited and had to be dowsed with earth; no environmental impact
or health risk from fumes.
||SO2 emissions from acid plant stock over allowable
limits. Plant shut down and modified to prevent further problems;
no environmental impact.
|5 July 1982
||Significant incident following a major spill of product,
- 1 tonne of yellowcake, onto two personnel. Subsequently radiation
safety measures were investigated. No environmental detriment but
worker health was threatened and investigations continued.
|1 February 1983
||< 1 Tonne of low grade ore washed outside RRZ
with 150 m3 of RRZ water following drain blockage in heavy rainfall.
No environmental detriment.
|9 February 1983
||-200L of diesel spilt at a borefield 800m south of
pit #1; No significant environmental impact outside spill site.
|23 February 1983
||7 personnel exposed to above permitted levels of
radioactive contamination during modifications to yellowcake scrubbers;
exposures were short term and less than 5% of the annual limit for
designated workers; no environmental or health impacts.
||Small volume of sewage escaped from Jabiru east following
entry of stormwater into system; leading to pump failure; no significant
|9 March 1983
||Labourer exposed to radioactive dust concentration
above derived limits. Testing and whole body counting showed that
uranium in the body was less than the detection limit of the equipment;
no environmental or health impact.
|22 April 1983
||Less than 50L diesel escaped to Gulungul Creek from
a spill at a borehole site 74/1; no environmental detriment.
||A contractor, without authorisation, pumped a small
amount of RPM water outside the RRZ to use in tailings dam construction.
Action was stopped by RUM staff; tests showed no measurable contamination
on dam walls; no environmental impact.
|15 August 1983
||Minor tailings leak; contained with RRZ; no environmental
|20 September 1983
||-40 tonnes of low grade ore dumped outside the RRZ.
Clean up was carried out by RUM staff within the day; material returned
to RRZ; no environmental impact.
|16 November 1983
||-100L diesel fuel spilled from split fuel line at
borehole 77/2 over an area of 25 sq m. Area cleaned up and reseeded
no lasting environmental impact.
|25 January 1984
||-100 cu m RP2 water escaped from a pipeline within
the RRZ; all water contained, no environmental impact.
|9 April 1984
||Estimated 200L spilled from a tank at bore 77/13
when it was tipped over. Area cleaned up and sanded to assist revegetation;
no significant environmental impact.
|11 July 1984
||-200 cu m liquid from RRZ leaked outside the RRZ
from a joint in a pipe carrying tailings dam seepage back to the
dam. No environmental impact.
|30 October 1984
||-600 litres of water leaked outside the RRZ from
the tailings dam seepage collector line; no environmental impact.
|14-16 February 1985
||Fish kill in RP2 was reported after water was pumped
from RP4; no environmental significance as natural fish kills are
reasonably common and also fish may have died through passing the
pump. No environmental significance.
|28 February 1985
||Monthly sampling at product packing stack showed
uranium levels close to the allowable limit; remedial work undertaken
by RUM to repair scrubber system; no environmental impact.
|20 March 1985
||Small quantity of tailings dam water sprayed and
ran off the tailings dam wall; water mostly returned through the
seepage collector system in all probability; no environmental impact.
The OSS expressed concern over delays in taking positive action
to stop the leakage.
|28 June 1985
||RUM detected a level of acid mist above the authorised
limit; remedial work alleviated the problem and prevented recurrence;
no environmental significance.
|31 July 1985
||A tailings pipeline failure led to -kg of tailings
being sprayed outside the RRZ; no environmental significance.
|1 and 19 August 1985
||A tailings pipeline failure led to -kg of tailings
being sprayed outside the RRZ; no environmental significance.
||Scaffolding stained with ammonium diuranate was shipped
off site to Darwin for re-use; no environmental significance.
|2 September 1985
||-50 cu m of RRZ water was released accidentally onto
an area outside the RRZ adjacent to the irrigation area; no environmental
|3 September 1985
||A small island of tailings appeared above water in
the tailings dam; no environmental significance.
|17-18 September 1985
||Approximately 25 cu m of tailings being sprayed outside
the RRZ on each day. No environmental significance after clean up
had been completed.
|24 September 1985
||A tailings pipeline failure resulted in -25 cu m
of tailings being deposited over an area of 1250 sq m to a depth
of 2 cm, outside the RRZ. No environmental detriment after clean
|3-7 October 1985
||Estimated 500 cu m of process water accidentally
sprayed onto land application plots in the RRZ. No lasting environmental
|26 November 1985
||200L of water leaked from a pipeline between the
central seepage collector sump and the north wall of the tailings
dam. No environmental detriment.
|4 March 1986
||Comparatively high levels of sulphur dioxide emitted
during acid plant start up; no environmental detriment.
|6-7 March 1986
||Small tailings island developed in the tailings dam
overnight; no environmental significance.
|3 June 1986
||-5 cu m of tailings dam water was spilled outside
the RRZ from the return pipeline; no environmental detriment.
|5 December 1986
||RUM reported the unlawful removal from site of an
empty but radiologically contaminated water tank (truck mounted;
after negotiating with the owner the tank was returned to site and
RUM control; no environmental significance.)
||DME determined that RUM were 6 months overdue in
submitting a report on revegetation of waste rock as required by
ER 26. Also water from RP3 (RRZ) had been used for dust suppression
outside the RRZ on a waste rock dump haul road. Neither incident
was considered to be of lasting environmental significance.
||-500 cu m of RP4 water was inadvertently released
via the pipeline to Magela Creek following a valve malfunction and
when the creek flow was below the minimum approved rate; no lasting
environmental significance and a blanking plate was inserted into
|1-2 February 1988
||An overflow occurred of mill process froth from a
tailings neutralisation patchuca; approximately 13 cu m of liquid
ran into RPM but no liquid left the RRZ; no environmental significance.
|31 August 1988
||Minor RRZ infringement when a contractor inadvertently
used a small quantity of RRZ water for dust suppression outside
the RRZ; no adverse environmental impact.
|22 October 1988
||A small quantity of tailings sprayed, mostly into
the tailings dam itself, from a burst gasket in the tailings dam.
No risk to workers nor harm to the environment resulted from the
||Following a malfunction of ore discriminators material
containing low grades of uranium was being dumped incorrectly on
the waste rock dump, up to 500,000 tonnes of material may have been
involved. The area of the waste rock dump was redesignated as RRZ.
No environmental detriment was detected as a result of this incident.
|20 March 1989
||RPM water level was allowed by RUM to reach a level
almost 1 m above the agreed wet season limit desirable to prevent
overtopping as a result of a 1-in-100 year storm event. No environmental
||Approval was given by the NT supervising authority
for release of water from RP4 via the spillway. This provided less
assured control of the environmental impact of the released water
than direct discharge to Magela Creek via the installed pipeline.
||Approval was given by the NT supervising authority
to shut down temporarily (for up to two years) the seepage collector
system in the Ranger tailings dam in contravention of ER10. The
purpose of the closure was to obtain information on the migration
of seepage away from the tailings dam so as to calibrate a theoretical
model of ground water solute migration.
|9 April 1989
||The daily approved application rate of water to the
land application area was exceeded. There may have been a small
amount of runoff. No environmental detriment was detected as a consequence
of this incidence.
|13-14 August 1989
||About 315 cu m of RRZ water were used for fire fighting
when a bush fire threatened both the Ranger and Alligator Rivers
Region Research Institute laboratories. No environmental detriment
as a consequence of this incident.
|25 April 1990
||A small quantity of tailings sprayed from a pump
when the casing failed. No material left the RRZ and a thorough
clean up was completed with no environmental detriment.
|22 June 1990
||Approximately 2.5 to 3 cu m of tailings leaked from
a split pipe; all material was contained with the RRZ, no environmental
|27 March 1991
||Approximately 320 cu m of additional water were applied
to the land application area following equipment malfunction. The
water fully infiltrated and there was no runoff. No environmental
|24-25 August 1991
||Approximately 1300 cubic metres of RRZ water (from
RP2) was inadvertently used on the perimeter road of the tailings
dam to suppress dust. Because of the quantity and quality of the
water involved, and of the location of the incident, there would
have been no ecological impact and there was no health risk to workers
or members of the public.
|26-27 February 1992
||During a high rainfall event, water from the high
grade ore stockpile, which contained significant concentrations
of uranium, escaped from its containment sump and flowed into Georgetown
Creek, then into Magela Creek. The concentrations of uranium that
eventuated in Magela Creek from this incident were too low to have
had an ecological effect and the quantity of uranium lost to the
environment would have caused no harm to human health.
|27 September 1992
||Approximately 430 cubic metres of water from RPM
was transported by mine trucks to locations outside the RRZ for
use by the Ranger emergency fire crew in containing and controlling
a bushfire burning in and near the Ranger Land Application Area.
The fire, which was fanned by strong winds and was burning on a
number of fronts, threatened infrastructure, including monitoring
installations and powerlines close to RPM, and also threatened to
move towards the light industrial area and the Jabiru East site.
There were no alternative sources of water in sufficient quantity
available to fight the fire. The Supervising Scientist assessed
the transfer of water from the RRZ as constituting an infringement
of the Ranger Authorisation and a breach of the ERs. The risk to
the environment from the reported use of this water was negligible.
|25 January 1993
||During heavy rainfall a blocked drain caused a small
volume (less than 100 cubic metres) of water to escape from the
RRZ. The Supervising Scientist assessed this event as being an infringement
of the Ranger Authorisation and a breach of ER27. The release of
this water would have had trivial environmental consequences.
|21 October 1993
||Failure of a component in the tailings dam sprinkler
system, used to minimise dust generation resulted in wind blown
spray drifting over the dab embankment outside the RRZ boundary.
This resulted from coincidental high winds from the NNW at the time
of the failure. The quantity of water was small and the area was
cleaned up within two days. An evaluation of the likely radiological
effect suggested there was no radiological impact beyond natural
background. The sprinkler system was repaired and has functioned
correctly since the incident.
|13 April 1994
||About 60 cubic metres of combined rainfall-runoff
and seepage from the high-grade ore stockpile discharged outside
the RRZ following a pipe joint failure. The pipe ran alongside the
drain downstream of the RRZ boundary at the bund in the high-grade
ore stockpile drain. Samples taken along the flow path showed an
increase in uranium concentration in Georgetown Creek but no change
in uranium concentration could be detected in Georgetown Billabong.
The pipe has since been relocated wholly inside the RRZ.
|10 May 1994
||About 50 cubic metres of RPM water was accidentally
discharged outside the RRZ during the installation of a new section
of pipe at the RPM pumping station. The pipe was part of the network
that serves the irrigation area. The incident caused no measurable
|20 July 1995
||About 10 cu m of RPM water was used in pre-production
drilling at ore body #3 outside the RRZ. The incident was not considered
to be of any environmental significance.
|1 August 1995
||Approximately 120 cu m of RPM water was accidentally
discharged outside the RRZ due to a failure in a pipeline carrying
water to the constructed wet land filter adjacent to RP1. The incident
was not considered to have any lasting environmental significance.
|6 December 1995
||-12cu m of diesel spilled from tanks at the power
station and ran into RPM. Although the spill was cleared up the
spill was responsible for the death of 40 water birds. The Supervising
Scientist regarded this incident as the first example of an unacceptable
environmental impact at Ranger since operations began.
|13 December 1996
||An administrative error resulted in a repeat of the
incident of 6 December when the residual diesel/water mixture was
spilled back to RPM. There were no further bird deaths associated
with this incident.
|23 January 1996
||2-3 cu m of tailings spilled from the tailings line
and went outside the RRZ. The incident was the result of a valve
failure. The area affected extended over about 60-80 sq m. This
soil and grass in this area were removed and the site mulched and
reseeded. The valve and the associated support structure were replaced.
There was no lasting environmental impact from this incident.
|18 February 1996
||-2 cu m of tailings sprayed from a leak in the pipeline
running along the top of the tailings dam embankment. Approximately
0.25cu m fell outside the RRZ on the outer wall of the dam. This
area was scraped up and returned to the tailings dam. There was
no environmental impact as a consequence of this incident.