NEIGHBOURING COMMUNITIES
The preponderant interest of submissions lodged with the Committee
which addressed the topic of the health and safety of neighbouring communities
was the impact of uranium mining and milling on Aborigines. The effects
of uranium mining and milling on Aborigines are the theme of chapter
5.
Both the mining companies and the respective government authorities
provided the Committee with information about radiation in the vicinity
of the mines.
ERA reported that since 1989 dust monitoring has focussed on Jabiru
and Jabiru East. ERA explained:
These two locations are monitored every month continuously
for one week. This monitoring frequency will continue while the monitoring
results indicate acceptable variations. Radon daughter concentrations
are also monitored at the same locations and at the same frequency.
The results and wind data are the inputs to the Ranger model for the
assessment of radiation doses to the critical group.
Results from radiation monitoring at Jabiru has [sic] shown
that for the last four successive years, radiation doses have been
0.03 mSv, 0.10 mSv, 0.03 mSv and 0.04 mSv. (S 63, 45)
These are well within the new international levels.
According to ERA, background radiation in the area is in the range
of 2-3 mSv (ERA, S 63, 45).
ERA's report is confirmed by the Northern Territory Government (S 100,
29).
The Supervising Scientist sheds the following light on this matter:
[E]RISS has developed a method of separately identifying the
mine-related and background components by measuring radon and radon
progeny concentrations arising from wind sectors containing only the
natural background sources, and those from wind sectors containing
both background sources and mine-related sources. Following the completion
of this research, ERA has used a simplified version of the method,
but one that is adequate for routine monitoring at Ranger, to make
public dose estimates. The results obtained in this program . . .
show that radiation exposure of members of the public living in the
vicinity of the Ranger mine due to the dispersion of radon and its
progeny from the mine site has always been less than 10% of the recommended
dose limit.
Similar methods have been used to determine the dose due to
dispersion of radionuclides in dust from the mine. The estimated dose
for members of the public is about 5% of the recommended dose limit.
(S 85, Attachment B, Section 2.2)
The Committee recommends that these methods should be employed in
relation to all mines at which radioactive material is extracted.
Indeed, the Committee recommends that all mines should consult with
the Environmental Research Institute of the Supervising Scientist on
methodologies and technologies for identifying and monitoring background
radiation at mine sites and in the region where the mine is located.
The Committee's interest here lies not only in the technical adequacy
of monitoring but in the independence and transparency of the process.
This is a matter on which reports should be made to the consultative
committees whose establishment at each mine is recommended in chapter
2.
The Supervising Scientist also conducts research on surface water transport
of the long-lived radionuclides of the uranium series contained in waters
discharged from the mine. Drinking water is not affected as the local
potable supply is derived from groundwater bores that are unaffected
by mining ( S 85, Attachment B, section 2.2).
Estimated doses of radiation exposure are so low that the use of whole
body monitoring to detect them is not justified. Similarly radiation
exposure of members of the public is so low that it is calculated, not
measured, (S 85, Attachment B, Section 2.1).
ERISS research results show that the estimated radiation dose to members
of the public from discharge of waters from RP1 and RP4 at Ranger is
less than the dose limit by more than a factor of 20 ( S 85, Attachment
B, section 2.1).
The Northern Land Council informed the Committee that it "considers
that the mine related public dose at Jabiru is currently satisfactory"
(S 42, 21).
The NLC did advance two matters of concern to it. The first was whether
Aboriginal people can live closer to the mine. Their second concern
is that groups are defined as larger than 30 people. This approach,
according to the NLC, means that small camps living near the mine may
be overlooked.
Another matter of concern to the Northern Land Council is the dose
level at rehabilitated sites. The NLC recommends that the final dose
rate on a rehabilitated site should be no greater than that existing
before mining started. They continue: "[O]ur reasoning is based
on the risk from radiation exposure and the need to ensure this risk
is not increased following the cessation of mining" (S 42, 21).
They also propose that "[n]o mining should be allowed until there
is a good understanding of the radiological conditions at the mine site
and in the surrounding country. If the NLC's recommendation is adopted,
it should allay radiological concerns about mining and subsequent rehabilitation"
(S 42, 22).
The Supervising Scientist told the Committee in respect of Nabarlek:
One of the major aims of the Nabarlek mine rehabilitation was
the long term control of doses to adjacent communities. Nabarlek is
relatively unique in uranium mines in that all the ore was mined prior
to processing, which allowed the tailings to be placed in the excavated
pit. This enabled the mining company to dispose of all the waste,
including items from the mill which were not decontaminated or could
not be sold, by placing it into the pit from which the ore was mined.
This has greatly reduced the impact on the environment and will also
reduce the long term contribution to the radiation exposure of any
adjacent communities. Studies on the radiological characteristics
of the rehabilitated landform are underway; it is anticipated that
there will be no restriction from a radiological viewpoint on the
desire of traditional owners to undertake periodic camping and foraging
on the site. (S 85, 31)
The Supervising Scientist's activities in relation to radiation dangers
at decommissioned mines illustrate the expertise which it holds which
is available and valuuable to the entire uranium mining industry.
A program designed to allow assessment of radiation doses to members
of the public living near the Olympic Dam Operation, resulting from
the operations, is part of the approved Environment Management and Monitoring
Plan. Potential pathways of exposure to nearby residents are airborne
transport of radon and radon decay products and of radioactive dusts.
According to the South Australian Government, "[o]ther potential
exposure pathways which are important in mining projects in some environments
are not relevant at Olympic Dam. For example, the ingestion of potentially
contaminated food or water is not relevant, as virtually all food and
water consumed in the area is sourced from distant areas" (S 109,
19).
According to the South Australian Government:
Doses to members of the public living at Olympic Dam Village
and Roxby Downs are currently estimated from the results of continuous
radon decay product monitors, and high volume dust samplers. The dose
due to the project operations is difficult to derive from the monitoring
results, as it is only a small fraction of that from natural background.
The relatively small doses arising from radon decay products (which
contribute the majority of the dose), are particularly difficult to
estimate accurately, as the background concentrations show large natural
variations resulting from changes in atmospheric conditions. These
results are thus expected to be less accurate than those estimated
for workers. However, different methods of dose estimation (two different
modelling methods, and a monitoring method) have shown similar results.
Estimated doses for full time residents at the two residential areas,
Olympic Dam Village and Roxby Downs town, from 1988/9 to 1994/5 are
shown in Figure 3 [on p 20 of S 109], together with the recommended
annual dose limit for members of the public (1,000 microSieverts or
1 mSv). It should be noted that estimated doses to members of the
local community are of the order of 2% of the dose limit.
It has been alleged that rainwater tanks are prohibited at
Roxby Downs, because radioactive dust falling on the roof would contaminate
the water. Rainwater tanks are not prohibited, but comparatively few
have been installed because of the low rainfall. The results of dust
fallout monitoring show that any contamination would be insignificant.
(S 109, 19, 21)
Concerning the Olympic Dam Operation, the Conservation Council of South
Australia/Friends of the Earth Nouveau observed:
. . . tailings if allowed to dry out can be a dangerous source
of radon gas and contaminated dust. This gas and dust could be carried
by prevailing winds across to communities in the region including
Aboriginal communities, pastoral homesteads and residents of the Roxby
Downs township. It is possible, given certain weather conditions,
that contaminants could reach other regional population centres such
as Woomera, Port Augusta, Whyalla and Port Pirie and possibly as far
as Adelaide. (S 92, 29)
Planning for the proposed Kintyre mine fully includes occupational
health and safety of employees. Canning Resources states that it will
be using "the latest ICRP and IAEA recommendations, particularly
with regard to dose conversion factors" (S 65, 4-5).
Aboriginal communities in the Rudall River region have particular concerns
about health and safety dimensions of the proposed mine. Their concerns
include water contamination of rivers and underground water sources;
dust; tailings and waste disposal; radioactivity dangers associated
with transportation of the mine's product; and an equitable financial
return by way of compensation and land rental (S 52, G).
According to WDPAC, Canning Resources responses to these concerns state,
inter alia, that water run off will not enter the Rudall River system
but will flow into the desert sands and "disappear", and that
winds blow away from the communities (S52, G).
Canning Resources has informed the Committee that the environmental
impact assessment will concentrate on these matters (S 65, 8).
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