Page 328 - Annual Report 2020

Water discharges Total water discharges for FY2020 were 147,850 ML an increase
Water discharges includes water that has been removed from the from FY2019 as expected due to the increase throughout of
operated asset and returned to the environment or distributed the desalination facility at our Escondida asset. The majority
to a third party. This includes seepage from tailings dams to of water discharges are to seawater at over 90 per cent, with
groundwater, discharges from operations to surface waters Escondida and Petroleum being the largest contributors. The
(which are also affected by periods of higher rainfall) and discharges second largest discharge volume is to groundwater, the majority
to seawater. Water we treat and then on-supply to third parties of which is Type 3 seawater that is withdrawn as a by-product
is captured as a diversion consistent with ICMM Guidelines as it during the recovery of hydrocarbons from below the seabed (and
is not intended for operational purposes. Water that is evaporated therefore classed as groundwater in the ICMM and WAF guidance)
or entrained is also excluded from discharges and instead reported and which is returned by re-injection to below the seabed.
(1)
under the water consumption category. (2) Discharges to surface water (usually riverine systems) are influenced
by climatic conditions such as rainfall and occurrence of extreme
FY2017 – FY2020 Total discharges (by destination) weather events, therefore are subject to higher variability and less
Per million megalitres predictable. These scenarios may occur at our Queensland Coal
operated assets. In FY2020, some localised high rainfall events
1.5
resulted in discharges to surface waters at those operated assets.
Our water management practices at the operated assets where
1.2 ● Seawater this may occur are designed to accommodate this variability
● Groundwater and therefore the occurrence of such events does not affect our
9 ● Surface water current management activities and strategy or result in elevated risks.
● Third party water Approximately 40 per cent of our assets do not have any water
6 discharges due to water being either consumed in operational
activities or reused/recycled. This is similar to previous years,
3 but note that prior to FY2019, the definition of water discharges
included water that was evaporated or entrained. This is now
reported as consumption, in line with ICMM Guidelines. The
0 extent of this change is shown in the data tables in section 6.6.3.
2017 2018 2019 2020 Water recycled/reused

FY2017 – FY2020 Total discharges (by quality) During FY2020, the total volume of water recycled/reused was
250,090 ML. This represents an efficiency of 66 per cent of
Per million megalitres
withdrawals excluding seawater. Increases in recycled/reused
1.5 volumes was observed at five of our operated assets in FY2020.
The ability of our operated assets to reuse and recycle water varies
1.2 ● Type 3 depending on the recovery processes used and the water quality
● Type 2 requirements. The accuracy of the recycled/reused metric currently
9 ● Type 1 varies depending on the complexity of the process and how closely
water movements are measured and understood. As our data
6 collection and analysis improves, we can more robustly assess
opportunities to improve efficiency of water use.
3 Water diversions
FY2019 was the first year that BHP disclosed diversions. Diverted
0 water is water that is actively managed by an operated asset but
2017 2018 2019 2020 not used for any operational purposes. For example, this includes
the water that is removed from below the water table at WAIO
to access the ore but is returned to the environment and not
FY2020 Discharges by asset (by destination) consumed in operations. Another example is when we withdraw
Per million megalitres water and treat it for use as drinking water by local communities,
as Olympic Dam does for the town of Roxby Downs in South Australia.
1.0
In FY2020, 102,780 ML of water was withdrawn without any
intention to be used at BHP operated assets, predominantly relating
8
to water that is treated by our legacy assets in North America, and
6 by dewatering as noted above for WAIO, and described further in
the WAIO water case study.
4 Note the withdrawal of diverted water may occur in a different
annual reporting period to its discharge, so in any given annual
2 period there may be a differential between withdrawal and
discharge volumes for diverted water.
0
Escondida Petroleum Queensland Coal (BMA/BMC) Western Australia Iron Ore Potash Canada Nickel West Olympic Dam Pampa Norte NSW Energy Coal Legacy sites

● Seawater ● Surface water ● Groundwater ● Third party water

(1) Entrained water includes water incorporated into product and/or waste streams, such as tailings, that cannot be easily recovered.
(2) Evaporation and entrainment, previously reported as water outputs under the WAF, have been reported under consumption to align with the ICMM Guidelines.

326 BHP Annual Report 2020