Journal of Water Resource and Protection, 2012, 4, 1061-1070
http://dx.doi.org/10.4236/jwarp.2012.412122 Published Online December 2012 (http://www.SciRP.org/journal/jwarp)
Recreational Use of Acidic Pit Lakes—Human Health
Considerations for Post Closure Planning
A. L. Hinwood1, Jane Heyworth2*, Helen Tanner1, Clint McCullough1
1Centre for Ecosystem management, Edith Cowan University, Perth, Australia
2Population Health, University of Western Australia, Perth, Australia
Received August 7, 2012; revised October 1, 2012; accepted October 15, 2012
ABSTRACT
Pit lakes may form in mining voids that exten d below gr oundwater lev el after mining ceases and many ha ve been found
to have elevated metals concentrations and low pH through acidic and metalliferous drainage (AMD). Pit lakes are of-
ten used for recreational activities including swimming, fishing and boating and poor water quality may present health
risks to recreational users. Pit lakes also provide the opportunity for additional water resource uses. The Collie Coal
Basin in south-western Australia currently has a number of pit lakes with moderate AMD effects which are also used
for recreational pursuits. Twelve hundred questionnaires were mailed to selected addresses in the Collie shire with an
additional 170 questionnaires to specific interest groups. Participants were asked about the type of activity, frequency
and duration and any health symptoms experienced after use of the lakes. Two hundred and fifty questionnaires were
returned, which comprised 176 returns from the random sample and 74 from the targeted sample. Three pit lakes with
elevated metals concentrations and low pH were used for recreati o na l purposes by 62 % of r es pondent s . This was most ly
in summer with swimming the most commo n activity. Of all respondents 52% were concerned about lake water quality
and 38% using the lakes reported a variety of symptoms. Recreational use of Collie pit lakes did not rep resent a health
risk for most of the surveyed population due to th e low frequen cy and duration of use, however health risk s may be ele-
vated in sensitive users such as children and those consuming seafood from the lakes. Comprehensive water quality
monitoring for chemicals and further characterisation of recreational use of pit lakes is warranted to more comprehen-
sively assess the potential health risks to recreational users. Post closure mine plans need to consider potential future
community uses combined with assessments of water quality and physical characteristics to reduce the potential for
adverse health and safety impacts.
Keywords: Pit Lake; Acidity; Metals; Recreational Use; Health Impacts; Management
1. Background
Open cut mining has left a legacy of many thousands of
mining pit voids worldwide with increasing frequency
and scale [1-4]. Pit lakes are formed in mine voids once
extractive and dewatering operations have ceased and
water has accumulated through surface and groundwater
inflows [3,5]. The water quality of pit lakes is variable
and is an aspect determined by the geology of the void,
water inflow quality, groundwater quality and surround-
ing activities and land uses including the presence of
waste rock [6,7]. Water quality of coal pit lakes is often
poor as a result of low pH and elevated metals concentra-
tions caused by acidic and metalliferous drainag e (AMD)
resulting from weathering of sulphidic minerals such as
pyrite [6]. Metals is the term being used in this paper to
describe heavy metals, metalloids and transitional metals.
Following mine closure, closure plans are imple-
mented to minimise environmental harm and address
potential social impacts by providing for a geotechnically
stable and safe mine void [8,9]. Future use of the pit
lakes by the community has largely been ignored in the
planning process. Over the past ten years the interna-
tional mining industry and regulators have increasingly
considered the importance of the benefits of pit lakes as
additional community water resources and there has been
some recognition that pit lakes may have potential bene-
ficial end uses that could contribute economic, health,
welfare, safety or aesthetic benefits assuming a degree of
remediation and management [7,10]. Activities such as
tourism (swimming, fishing and boating), wildlife con-
servation and irrigation water for agriculture and horti-
culture have been highlighted as possible beneficial end
uses [7,10].
The physico-chemical characteristics as well as geo-
technical aspects can influence the future use of pit lakes.
*Corresponding a uthor.
C
opyright © 2012 SciRes. JWARP

A. L. HINWOOD ET AL. 1062
Features such as the steep walls associated with the min-
ing process and depth need to be considered where
community use is an option. Clarity is another important
characteristic of lakes and is influenced by microscopic
plants and animals, suspended particles and dissolved
substances such as iron [11]. There are also a range of
organisms that can survive in acidic pit lakes and hence
present risks to users [12]. The potential for microor-
ganisms to cause an adverse health impact is dependent
on the pathogen, its form, the cond itions of exposure, the
hosts susceptibility and immune status [13]. Water bod-
ies used for recreational purposes are likely to contain
faecal matter that may be harmful to health. E coli is tol-
erant of acidic conditions. Crypotsporidium and Giardia
spp. are faecally derived protozoa that can survive for
significant durations outside their host organisms. It is
not known at this time whether these species exist in pit
lakes, however much has been written about these path-
ogens in terms of recreational water bodies [14].
Activities around pit lakes such as walking and camp-
ing may also increase risks in terms of injury due to the
distinct physical aspects. Pit lakes, particularly in hard
rock areas, can have steep sides and great depth making
it easy for waders and swimmers to get out of depth and
experience difficulties getting out of water. Poor clarity
of the water and strong colour stains may also make the
depth of the water difficult to assess [11].
Limited research has been undertaken to assess the
risks of health effects from recreational activities under-
taken at pit lakes. Doupe and Lymbery [7] ranked the
risks of recreation and tourism of pit lakes as high when
considering a variety of beneficial uses. Many authors
have commented on the biological quality of surface wa-
ter bodies and the potential health risks associated with
recreational use [15,16]. There has been little focus on
the chemical water quality of pit lakes and risks of hu-
man exposure to low pH and elevated metals concentra-
tions for recreational users. This is compounded by little
information on the types, frequency and duration of ac-
tivities in pit lakes to inform health risk assessment.
The Collie region of south-western Australia currently
has 13 mine pit lakes with two public lakes used regu-
larly for recreational activities [17]. The water quality of
pit lakes in Collie varies with some high concentrations
of metals recorded and low pH (4.0 - 5.5) [18,19].
Our study aimed to describe the recreational use of the
Collie pit lakes and from this assess the likelihood of
exposure to elevated metals concentrations and low pH.
This assessment of the potential for health impacts wou ld
hence inform management of pit lakes for recreational
use.
2. Materials and Methods
A cross sectional questionnaire survey was conducted of
recreational use of pit lakes in residents in the Collie
Shire, south-western Australia. This was combined with
a review of available surface water quality data for the
lakes. The study received ethics approval from the ECU
Human Research Ethics Committee 2009.
2.1. Study Area
Collie is located in the South Western region of Western
Australia and has a Mediterranean climate consisting of
cool winters and hot dry summers. Coal has been mined
in the Collie area since 1888, with coal used predomi-
nantly for generation of electricity [20]. Discontinued
mine voids have been present in the area for approxi-
mately 50 years [20].
Situated in the Collie Coal Basin, the town of Collie
experiences higher rainfall than many other areas of the
state with average rainfall of 932 mm (Commonwealth of
Australia Bureau of Meteorology, 06/08/2011). The ma-
jority of mines in the area are open-cut mines below the
ground water table, resulting in pit lakes at closure [21].
Currently two lakes, Stockton and Black Diamond, are
used by the public for recreational activities (Figure 1).
Nearby Lake Kepwari is also being considered as a rec-
reational area although it was not open to the public.
Nevertheless, although the lease holding mining com-
pany has attempted to prevent access, many people still
use the lake.
2.2. Study Population
The study population was residents living within the
Shire of Collie, a population of 9104 people [22]. We
determined that 264 responses were required to estimate
the prevalence of recreational use with a 90% confidence
level and an Type 1 error of 5%.
2.3. Study Recruitment
Two methods were used to recruit participants; a random
postal survey of Collie Shire residents and a targeted
survey. A mailing list of 1300 postal addresses in the
Collie Shire (postcode 6225) was randomly selected from
the 2004 White Pages phone directory by the Edith
Cowan University Survey Research Centre. Towns in
this postcode included Collie, Allanson, Buckingham,
Collie Burn, Noggerup, and McAlinder. An information
package was prepared and posted to 1200 households
from the mailing list. An additional 100 addresses were
available for mail-out where there were no householders
at the current address. The package included a letter of
invitation to participate, the questionnaire, an informa-
tion sheet and a reply-paid envelope for questionnaire
return. One person from each household was asked to
answer the questionn aire about their ind ividual use of the
it lakes. p

A. L. HINWOOD ET AL. 1063
Australia
Perth
Collie
BlackDiamondA
Stockton
CardiffSub‐basin
PremierSub‐basin
04km
N
COLLIE
Kepwari
Figure 1. Location of study area and pit lakes.
A second recruitment stage took place with 40 infor-
mation packages sent to special interest groups. Member
names from these groups were supplied by the Western
Australian Government Department of Water. Copies of
the questionnaire were also made available at the local
council and library. Reply paid envelopes were left at
both locations for return of questionnaires. An informa-
tion booth was also set up at the local shopping centre to
recruit more participants and to provide background in-
formation about the study. The researchers targeted peo-
ple at the local shopping centre over a two day period in
November 2009 asking them to complete a questio nnaire.
Respondents to the questionnaire needed to be over 18
years of age.
er), giving a response fraction of 16%. Another 74 (44%)
questionnaires were received from the 170 distributed to
the targeted audience.
2.5. Data Management and Analysis
All data was entered into a Microsoft access database and
double entered. The data were checked for accuracy and
cleaned. Descriptive statistical analyses were performed
using SPSS version 17.0 Responses from the random and
targeted sample groups were similar for all study vari-
ables except for the proportion who used the lakes. For
the randomly selected group 58% used the lakes in the
past two years, whereas 69% of the target group had used
the lakes. Consequently, responses from the combined
group are presented in relation to the lake activities
among users.
2.4. Data Collection-Questionnaire
The questionnaire addressed use at the three most popu-
lar lakes. Questions included time spent by respondents
and their families using one or more pit lakes for recrea-
tion, time spent in contact with lak e water and what type
of activities they undertook. Respondents were also
asked about: any health symptoms they experienced fol-
lowing use of the lakes; their views on management of
the lakes; and the uses that should be permitted.
Swimming, wading and water skiing were classified
into a single category to determine time spent undertak-
ing water based activities. When calculating the average
time spent undertaking each activity, variables with more
than 12 hours (three questionnaires) were not used as it
was deemed unlikely that an individual would spend over
this amount of time per visit undertaking one activity
(excluding camping). The total amount of time spent
undertaking water based activities was calculated for
each lake by summing the amount of time taken for each
activity together. An average was then taken of all re-
spondents who had spent time undertaking water based
activities.
Questionnaires were coded distinguishing between the
random sample and the targeted population. In total 250
questionnaires were available for analysis. From the
randomly selected group 176 questionnaires were ob-
tained from 1095 delivered (105 were returned to send-

A. L. HINWOOD ET AL. 1064
3. Results
3.1. Population Characteristics
The population surveyed was predominantly male and
older with a mean age of 56 years (Table 1). Both males
and females used the pit lakes with a slightly higher per-
centage of males using the lakes for recreational pur-
poses. One hundred and fifty four people indicated they
had used the pit lakes in the last two years. Respondents
visited Black Diamond and Stockton Lakes for a median
of two days per month and most visitors spent time at both
lakes (Tables 1 and 2). The number of children who vis-
ited the lakes was small with only 23% of children under
12 years of age. Not surprisingly, visits to lakes were
highest in spring/summer and lowest in autumn/winter
(Figure 2). The majority of adults who attended the lakes
visited in the afternoon and spent on average between 3 to
5.5 hours in water based activities ( Table 3).
3.2. Types of Activities Undertaken at the Lakes
Swimming was the most popular water based recreation
amongst adults for each of the lakes (Table 4). Among
participants who used the lakes, the highest percentage of
participants swimming was at Black Diamond. Boating
and water skiing were undertaken more often at Stockton
Lake than the other lakes. Of the non water-based active-
ties, picnicking at Stockton Lake was the most common
activity (Table 4).
The types of activities undertaken at each lake did not
differ by sex except at Lake Kepwari where men under-
took all of the listed activities whereas women undertake
swimming, wading, boating and picnicking (data not
reported).
Of the water based activities, more time was spent
water skiing and boating (Table 4). Of those who went
swimming, Stockton Lake had the highest average hours
spent swimming. Respondents who used the pit lakes
Table 1. Demographic characteristics of respondents categorised by pit lake use.
People who did not
use pit lakes People who used pit lakes Total population
Total population (n = 250) 38.4% 61.6%
Random population (%) (n = 176) 41.5% 58.5% 70.4%
Targeted population (%) (n = 74) 31.1% 68.9% 29.6%
Median distance lived from lakes (km) (range ) 10 (0.5 - 65) 8 (0.4 - 80) 10.6 (0.4 - 80)
Age mean (years) 60 50 54
Range 19 - 90 18 - 82 19 - 90
(n) (94) (150)
Sex (Male %) 38.5 % 61.5 % 57.2%
(n) (143) (143) (143)
Among those using the lakes
Household with children 13 - 18 yea r s (%) - 16.6%
Households with children < 12 years (%) - 23.2%
Table 2. Median number of days respondents visited each Collie pit lake, among those who used the pit lakes (n = 154).
Black Diamond Kepwari Stockton
Median number days/month 2 1 2
Range 1 - 30 1 - 4 1 - 20
(n) (125) (32) (115)
Median number days/year 10 2.5 8.5
Range 1 - 360 1 - 20 1 - 300
(n) (122) (34) (115)

A. L. HINWOOD ET AL. 1065
Percentage of adults who visted each pit lake
70.0%
60.0%
50.0%
40.0%
30.0%
20.0%
10.0%
0.0%
BD
LK
SL
O
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months of the year
Figure 2. Distribution of re spondent visits to lakes by month of year; BD: Black diamond; LK: Lake kepwari; SL: Stockton
lake; O: Other lakes.
Table 3. Reported time of day respondents most likely to
visit the pit lakes (n = 154*).
Time most likely
to use pit lakes Percentage (%) Average time of water-based activities (h)
All Day 21.5 5.4
Morning 8.1 5.5
Afternoon 65.8 3.3
Dusk 3.3 3
Night 1.3 0
*Data missing for 5 respondents.
for camping spent most time at Stockton Lake (Table 4).
The range of responses given for the amount of time
taken when undertaking each activity varied greatly and
also varied between the lakes. Across the lakes and ac-
tivities, respondents spent on average 2 hours under-
taking water based activities.
The number of people who indicated they ate seafood
(freshwater crayfish marron Parastacidae: Cherax tenui-
manus) caught from the pit lakes was higher than the
number of respondents who said they went fishing. Forty
two respondents said they ate seaf ood caught fr om the pit
lakes (data not shown). Of the people who went marron-
ing 90% (n = 31) ate their catch and of the respondents
who said they did not go marroning 13 indicated they ate
seafood which was caught from the pit lakes.
3.3. Self Reported Health Effects
From a list of health symptoms, respondents were asked
whether they experienced any after using the pit lakes.
Health symptoms were reported by 38% of participants
(Table 5). The most common symptom experienced by
Table 4. Percentage of respondents reporting recreational
activities and time spent on these activities at each Collie pit
lake (%).
Black
Diamond
(n = 127)
Lake
Kepwari
(n = 32)
Stockton
Lake
(n = 123)
Swimming % 83.5% 53.1 72.4
Mean Hours 2.6 2.5 2.9
(range) 0.5 - 12 1 - 6 0.5 - 12
Kayaking/Canoeing %15.0 3.1 1 5 .4
Mean Hours 1.7 1.0 2.8
(range) 0.5 - 4 1 0.5 - 10
Wading % 31.5 21.9 24.4
Mean hours 2.2 1.2 2.5
(range) 0.5 - 10 1 - 2 0.5 - 10
Boating % 6.3 9.4 40.7
Mean hours 3.0 1.6 3.7
(range) 1 - 5 1 - 2 0.5 - 12
Water skiing % 2.4 3.1 27.6
Mean Hours 4.3 2.0 4.4
(range) 4 - 5 2 2 - 12
Fishing (marroning) %1 1 .0 9.4 12.2
Mean hours 3.3 n/a 4.0
(Range) 1 - 6 2 - 6
Picnicking % 42.5 40.6 47.2
Camping % 20.5 9.4 30.9
Walking % 7.9 9.4 2.4
Other % 7.1 28.1 11.4

A. L. HINWOOD ET AL. 1066
Table 5. Percentage of respondents who reported health symptoms after visiting the pit lakes.
Never Sometimes Most times
Adult (%)
(n = 140) Children (%) (n = 32) Adult (%) (n = 140) Children (%) (n = 32) Adult (%) (n = 140) Children (%) (n = 32)
Skin rashes/irritation 91 94 7 6 2 0
Sore Eyes 78 81 19 19 4 0
Feeling sick 98 100 2 0 0 0
Vomiting 100 97 0 3 0 0
Diarrhoea 99 100 1 0 0 0
Runny nose 90 91 8 9 2 0
Headaches 91 94 7 6 1 0
Feeling tired 91 91 8 9 1 0
Temperature 97 100 2 0 1 0
Sore throat 91 94 7 6 2 0
Other 99 97 0 0 1 3
adults was sore eyes with 19% experiencing this some-
times, and 4% experiencing sore eyes most times they
undertook recreational activity at the lakes (Table 5).
Skin irritations/rashes, runny noses, headaches, sore
throats and feeling tired were other symptoms experi-
enced (Table 5).
The most common health symptoms reported for chil-
dren under12 yrs old was sore eyes. Other health effects
reported included feeling tired, runny nose, skin rash,
headaches or sore throat (Table 5). Males experienced
more symptoms than women reporting 9 out of the 11
symptoms and males reported having sore eyes more
often than females whereas females experienced head-
aches more often than males (data not shown). When
assessed by specific lake, more respondents reported
symptoms when visiting Black Diamond compared with
Stockton but the numbers were too small for analysis
(data not shown).
A comparison was made of the total amount of time
spent undertaking water based activities and the symp-
toms respondents reported (Figure 3) where more were
reported if they spent over 10 hours undertaking water-
based activities (Figure 3).
3.4. Water Quality Data
Limited surface water quality monitoring has been un-
dertaken at the Collie Pit Lakes and available data for
two lakes most commonly used for recreational activities
is shown in Table 6 and available guideline values for
selected metals and pH are also shown.
Typical of many coal geologies, Collie coal has pyrite
associated with the basin’s coal. Although Collie geol-
ogies are of low sulphur content, following exposure and
weathering, acidity is produced from oxidation, ferrolysis
and secondary mineralization [18]. pH of between 3.8
and 6.8 (averaging 4 - 5) have been recorded at three
lakes used for recreational purposes (Table 6). Th e three
year average pH meets the recreational water guidelines
however individual samples do not meet the guidelines
(Table 6). The metals concentrations are difficult to in-
terpret as there are limited samples and many of the de-
tection limits are higher than gu ideline values.
Aluminium concentrations at Stockton Lake were
above both the Au stralian Drinking Water Guidelines [23]
and recreational water guidelines [24] (Table 6). Arsenic
concentrations were also elevated and some samples ex-
ceeded both recreational and drinking water guidelines.
The few samples at Black Diamond were at the limit of
detection. At Stockton Lake, cadmium concentrations
were generally above detection limits with one sample at
the recreational water quality guideline level. Iron con-
centrations at Black Diamond and Stockton Lake did not
exceed the drinking water [23] or recreational water
guidelines [24] but again individual samples did. The
detection limits for lead were also above guid eline valu es.
Mercury concentrations at Black Diamond were high and
well above guideline values (Table 6). Interpretation of
mercury concentrations at Stockton Lake were influ-
enced by detection limits which were higher than the
relevant guideline values [23,24].
The pit lakes exceeded drinking water guidelines for
nickel [23] but not recreational water quality. Boron,
chromium, copper and zinc concentrations were well
below drinking water and recreational water guidelines
and are not reported here.

A. L. HINWOOD ET AL. 1067
Percentage of health effects expertenced (%)
Skin rashes/irritation
60
50
40
30
20
10
0
Tatal time undertaking water based activities
(Swimming, wading, waterskiing (hrs))
<2 3-5 hrs 6-10 hrs 11-15 hrs 15+ hrs
Headaches
Runny nose
Sore Eyes
Figure 3. Percentage of health effects by the amount of time spent undertaking water based activities.
Table 6. Three year mean surface water metal concentrations and pH at the Collie Pit lakes (µg/L) (McCullough et al., 2010).
Black Diamond Stockton ADWG* RWG*
Mean <DL (100) 529 7 50
Range <DL 23 - 1800
Aluminium
n 2 27
Mean 37.5 15.2 7 50
Range <DL - 50 0.5 - 64 Arsenic
n 2 22
Mean <DL (10) 1.4 2 5
Range <DL 0.05 - 5
Cadmium
n 2 21
Mean 51.5 121.8 200 200
Range <DL - 53 5 - 310 Iron
n 2 23
Mean <DL (100) 11.4 10 50
Range <DL 0.5 - 25 Lead
n 1 5
Mean 134 58.2 (3 yr) 300 300
Range 51 - 217 5 - 140 Manganese
n 2 26
Mean 170 27.5 1 1
Range 100 - 2 41 5 - 50 Mercury
n 2 2
Mean 37.5 47.7 100 100
Range 33 - 42 20 - 81 Nickel
n 2 3
pH 3y Av 5.5 4.9 6.5 - 8.5 5.0 - 9.0
Range 4.4 - 6.8 3.8 - 6.3
n (3) (20)
*Australian Drinking Water Guid elines (NHMRC/NRMMC (2004 ); **Australian and New Zealand Guidelines for Fresh and Marine Water Quality (Ch. 5 Rec-
eational water) (2000); <DL = Below Detection Limit. r

A. L. HINWOOD ET AL. 1068
3.5. Physical Characteristics of the Lakes
The pit lakes range from <1 ha up to 10 ha in surface
area with depths ranging from <10 m up to 70 m [17].
Most have beaches enabling easy access by members of
the community, although in some parts of the lake, the
characteristic steep sides can be observed.
The clarity of the pit lakes in Collie has b een measur ed
using Secchi depth in four lakes [19]. Black Diamond
recorded a mean Secchi depth of 3.3 m +/– 0.3 m, Blue
Waters recorded 4.1 m +/– 0.3 m, Ewington 3.8 m +/–
0.3 m and Lake Stockton recorded a mean Secchi depth
of 3.8 m +/– 0.4 m [24]. A Secchi depth to 1.6 m is suffi-
cient for water bodies used for swimming [24]. The lakes
exhibit different temperatures at different times of year.
Lund & McCullough (2008) [18] state the lakes in the
Collie region are monomictic and are thermally stratified
between November and March each year, however water
temperature were not stated for the individual lakes [18].
In spring, water temperatures ranged from approximately
16˚C to 20˚C. In summer, temperatures ranged from ap-
proximately 20˚C to 25˚C [19].
4. Discussion
The Collie Pit Lakes had variable water quality includ ing
pH. Clarity and temperature of the lakes were within
acceptable ranges for recreational pursuits. For the two
most commonly visited lakes in the Collie area, there
were few surface water quality data available and of the
data that were available, some individual sample concen-
trations of mercury, arsenic, manganese and aluminium
exceeded recreational water quality guidelines and a few
samples exceed drinking water guidelines. pH was con-
sidered low.
There was a high level of recreational use of the Collie
pit lakes among respondents to the survey. As would be
expected use is high in the warmer months of the year.
Families, the elderly and the young use the pit lakes for
water-based activities, particularly swimming. The lakes
were popular locations for picnicking and boating. An-
other popular activity was camping. A small number of
people reported fishing for crustacea and consuming the
seafood caught from the lakes.
It is acknowledged that it is difficult to estimate the
true population use of the lakes due to the high non-re-
sponse to this survey. However we expect that users of
the lakes were more likely to respond. For users of the
lakes there is no reason to believe th at the resp on se of the
participants regarding the nature of the use differ from
non-responding users of lakes. It is likely that non users
were a greater prop ortion in the non-r esponders, how ever ,
among the users of the lakes these data provide reason-
able estimates of the nature of the use. A greater response
to the questionnaire would have given a better represen-
tation of the recreational habits of the Collie community
and visitors from other regions at the pit lakes.
Health effects were reported by 38% of respondents
who visited the lakes. Visitors to Black Diamond and
Stockton Lake reported experiencing the most health
effects and the most common heath effect experienced by
both adults (22.3%) and children (18.8%) was sore eyes
followed by reports of skin irritations and rashes. There
was some suggestion of increasing symptoms with more
than 10 h of water related activities however there were
low numbers of respondents undertaking more than 10
hours of activity. We cannot draw conclusions about
nonspecific symptoms that may result from water related
use of pit lakes because of potential for selection bias and
the cross-sectional design. Participants who responded
may have done because they had experienced health ef-
fects and thus were more interested in the study. How-
ever, these data suggest that sore eyes may warrant fur-
ther investigation.
The recommended Australasian recreational guideline
pH for primary contact activities such as swimming is 5
to 9 [24]. Low pH can also remove outer skin layers in-
creasing susceptibility to absorption of chemicals [26].
Previous research has shown that pH below 5 can result
in both eye and skin irritation [11]. The pH at both
Stockton and Black Diamond lakes were low and could
result in some skin irritation in recreational users [25].
pH therefore, presents a risk for skin and eye irritation
for those with direct contact with the water and those
with conditions that may be exacerbated by low pH.
These results provide so me indication of the potential fo r
adverse symptoms. However, they are based upon self
reports and may be the result of other exposures occur-
ring at the same time.
While high concentrations of metals in drinking water
have been associated with many health effects, the results
of this survey suggest there are on ly low levels of risk to
health from exposure to elevated metals concentrations in
the pit lakes as a result of low frequency and duration of
use. These concentrations could present a risk to vulner-
able groups and in particular children who are likely to
be at a higher risk of adverse health effects due to their
developing status and potential for higher metal intakes
[25]. Another group at increased risk are those consum-
ing seafood as crustaceans which are known to accumu-
late metals [26] and therefore could introduce an addi-
tional exposure source.
There is clearly a need to better define the concentra-
tions of metals in these pit lakes and the contribution of
additional sources of exposure such as seafood. In addi-
tion, from a human health perspective while surface wa-
ter samples are relevant, the knowledge gained from un-
derstanding of processes in pit lakes is vital to account
for changes in water quality over ti me. For example con-

A. L. HINWOOD ET AL. 1069
centrations could be higher where turnover occurs in pit
lakes. This will also require regular targeted monitoring
of the pit lakes. Given the lack of monitoring to aid deci-
sion making, managers need to consider recreational use
and monitor water quality to determine seasonal and sp a-
tial variation with detection limits below current guide-
line values. Caution should therefore be exercised by
organisations managing these areas in terms of advice on
the potential health impacts for users and additional data
should be collected to enable an appropriate assessment
of risk.
The potential exists for a variety of human uses of pit
lakes where water is increasingly becoming an expensive
and scarce commodity. In addition, the growth of com-
munities in regional areas makes it likely recreational
opportunities from pit lakes will be pursued. Because
each pit lake is likely to vary in its physical characteris-
tics and physico-chemical processes, it is essential that
managers consider post closure uses that may include
recreational or human use of the water for other purposes
such as aquaculture.
There is limited literature on the potential for health
effects from recreational use of pit lakes and because
each pit lakes varies in its physical, chemical and bio-
logical characteristics, individual lakes need to be con-
sidered in terms of its use and the potential for human
health impacts. In some circumstances the physicoche-
mical characteristics may reduce biological activity in a
water body therefore reducing risks to recreational users
however recreational use may introduce faecal coliforms
and other organisms presenting significant risks which
managers need to consider.
It is therefore recommended that in the development of
post closure mine plans, the potential for human use be
identified and where this is likely, criteria reflecting ex-
posure sources, pathways and activities, water quality
objectives and recreational criteria pertaining to safety be
established. The approach could be modelled on the way
contaminated sites is viewed in terms of future beneficial
use and relevant criteria for remediation. This would oc-
cur alongside issues of stability and structural integrity
affecting the potential for injury from physical risks.
It is also recommended that managers of areas where
pit lakes are currently used for recreational purposes un-
dertake monitoring and evaluation of each lake in rela-
tion to the factors outlined above and target appropriate
parameters and detection limits.
5. Concluding Remarks
This study has shown that recreational use of pit lakes
may be more common than previously thought. Recrea-
tional use of Collie pit lakes did not represent a health
risk for most of the surveyed population due to the low
frequency and duration of use. However health risks may
be elevated in sensitive users such as children and those
consuming seafood from the lakes. Human health risks
will differ depending on the recreational activity, nature
and intensity and water quality of lakes. Comprehensive
water quality monitoring for chemicals and further char-
acterisation of recreational use of pit lakes is warranted
to more comprehensively assess the potential health risks
to recreational users.
Post mining pit lakes often represent an important re-
gional recreational resource and consideration of both
water quality and physical characteristics are required to
reduce impacts to health and safety. Hence post closure
mining plans should include consideration of future
community uses combined with assessments of water
quality and physical characteristics.
6. Acknowledgements
We would like to thank the community of Collie for re-
sponding to the Questionnaire. We would also like to
thank DOW staff for their assistance in providing infor-
mation on contacts in the region and distributing the
questionnaire. This project was part funded by the De-
partment of Water and the Australian Government’s Wa-
ter for the Future initiativ e.
REFERENCES
[1] H. Klapper and W. Geller, “Water Quality Management
of Mining Lakes—A New Field of Applied Hydrobiol-
ogy,” Acta Hydrochimica et Hydrobiologica, Vol. 29, No.
6-7, 2002, pp. 363-374.
doi:10.1002/1521-401X(200112)29:6/7<363::AID-AHE
H363>3.0.CO;2-E
[2] J. Crusius, R. Pieters, A. Leung, P. Whittle, G. Pedersen,
G. Lawrence and J. J. McNee, “Tale of Two Pit Lakes:
Initial Results of a Three Year Study of the Main Zone
and Waterline Pit Lakes near Houston, British Columbia,
Canada,” Mining Engineering, Vol. 55, No. 2, 2003, pp.
43-48.
[3] K. A. Filippova and V. V. Deryagin, “Chemical Hydrol-
ogy of Mine Pit Lakes of the Bakala Geotechnic System
(Southern Urals),” Water Resources, Vol. 32, No. 4, 2005,
pp. 427-433. doi:10.1007/s11268-005-0054-8
[4] C. D. McCullough, “Mine Pit Lakes: Closure and Man-
agement,” Australian Centre for Geomechanics (ACG),
Perth, 2011, 183 p.
[5] J. M. Castro and J. N. Moore, “Pit Lakes: Their Charac-
teristics and the Potential for Their Remediation,” Envi-
ronmental Geology, Vol. 39, No. 11, 2000, pp. 1254-
1260. doi:10.1007/s002549900100
[6] G. E. Miller, W. B. Lyons and A. Davis, “Understanding
the Water Quality of Pit Lakes,” Environmental Science
and Technology, Vol. 30, No. 3, 1996, pp. 118A-123A.
doi:10.1021/es9621354

A. L. HINWOOD ET AL. 1070
[7] R. G. Doupe and A. J. Lymbery, “Environmental Risks
Associated with Beneficial End Uses of Mine Lakes in
Southwestern Australia,” Mine Water and the Environ-
ment, Vol. 24, No. 3, 2005, pp. 134-138.
doi:10.1007/s10230-005-0084-0
[8] G. A. Doyle and D. D. Runnells, “Physical Limnology of
Existing Mine Pit Lakes,” Minerals Engineering, Vol. 49,
No. 12, 1997, pp. 76-80.
[9] S. L. Johnson and A. H. Wright, “Mine Void Water Re-
source Issues in Western Australia,” Water and Rivers
Commission, 2003, 93 p.
[10] C. D. McCullough and M. A. Lund, “Opportunities for
Sustainable Mining Pit Lakes in Australia,” Mine Water
and the Environment, Vol. 25, No. 4, 2006, pp. 220-226.
doi:10.1007/s10230-006-0136-0
[11] World Health Organisation, “Guidelines for Safe Recrea-
tional Water Environments: Volume 1 Coastal and Fresh-
waters,” Wold Health Organization, Geneva, 2003.
[12] B, Nixdorf, A. Fyson and H. Krumbeck, “Review: Plant
Life in Extremely Acidic Waters,” Environmental and
Experimental Botany, Vol. 46, No. 3, 2001, pp. 203-211.
doi:10.1016/S0098-8472(01)00104-6
[13] National Health and Medical Research Council, “Guide-
lines for Managing Risks in Recreational Water,” Na-
tional Health and Medical Reseach Council, Australian
Government, Canberra, 2008.
[14] S. Dorevitch, N. J. Ashbolt, C. M. Ferguson, R. Fujioka,
C. D. McGee, J. A. Soller and R. L. Whitman, “Meeting
Report: Knowledge and Gaps in Developing Microbial
Criteria for Inland Recreational Waters,” Environmental
Health Perspectives, Vol. 118, No. 6, 2010, pp. 871-876.
doi:10.1289/ehp.0901627
[15] T. J. Wade, R. L. Calderon, E. Sams, M. Beach, K. P.
Brenner, A. H. Williams and A. P. Dufour, “Rapidly
Measured Indicators of Recreational Water Quality Are
Predictive of Swimming-Associated Gastrointestinal Ill-
ness,” Environmental Health Perspectives, Vol. 114, No.
1, 2006, pp. 24-28. doi:10.1289/ehp.8273
[16] F. M. Schets, J. F. Schijven and A. M. de R. Husman,
“Exposure Assessment for Swimmers in Bathing Waters
and Swimming Pools,” Water Research, Vol. 45, No. 7,
2008, pp. 2392-2400. doi:10.1016/j.watres.2011.01.025
[17] C. D. McCullough, M. A. Lund and L. Y. L. Zhao, “Mine
Voids Management Strategy (I): Pit Lake Resources of
the Collie Basin,” Department of Water Project Report
MiWER/Centre for Ecosystem Management Report,
Edith Cowan University, Perth, 2010, 250 p.
[18] M. A. Lund and C. D. McCullough, “Limnology and
Ecology of Low Sulphate, Poorly-Buffered, Acidic Coal
Pit Lakes in Collie, Western Australia,” Proceedings of
the 10th International Mine Water Association, Congress,
Karlovy Vary, 2008.
[19] M. A. Lund, D. Bills, T. Keneally, S. Brown and S.
Thompson, “Bacterial Strategies for Increasing pH in
Acidic Voids,” Final Void Water Quality Enhancement:
Stage III, ACARP Project Number C8031 Report, Perth,
2000, pp. 169-222.
[20] C. Stedman, “100 Years of Collie Coal,” Curtin Printing
Services, Perth, 1988.
[21] S. Varma, “Hydrogeology and Groundwater Resources of
the Collie Basin, Western Australia,” Hydrogeological
Record Series HG 5, Water and Rivers Commission,
Perth, 2002, 80 p.
[22] Australian Bureau of Statistics, “National Regional Pro-
file: Collie (S) (Local Government Area),” 2009.
ucts/LGA51890Population/People12002-2006?opendocu
ment&tabname=Summary&prodno=LGA51890&issue=2
002-2006
[23] NHMRC/NRMMC, “Australian Drinking Water Guide-
lines 6,” National Health and Medical Reseach Council,
2004.
[24] ANZECC/ARMCANZ, “Australian and New Zealand
Guidelines for Fresh and Marine Water Quality,” Vol. 1,
Australian and New Zealand Environment and Conserva-
tion Council and Agriculture and Resource Management
Council of Australia and New Zealand, Canberra, 2000.
[25] J. W. Fluhr, R. Darlenski, I. Angelova-Fischer, N. Tsan-
kov and D. Basketter, “Skin irritation and Sensitization:
Mechanisms and New Approaches for Risk Assessment,”
Skin Pharmacology and Physiology, Vol. 21, No. 3, 2008,
pp. 124-135. doi:10.1159/000131077
[26] R. P. Mason, J. Laporte and S. Andres, “Factors Control-
ling the Bioaccumulation of Mercury, Methylmercury,
Arsenic, Selenium, and Cadmium by Freshwater Inverte-
brates and Fish,” Archives Environmental Contamination
and Toxicology, Vol. 38, No. 3, 2000, pp. 283-297.
doi:10.1007/s002449910038