Proper Water Management
With water management and water risk management1 being internationally recognized issues, we have prioritized proper water management as one of our Key Tasks.2
Additionally, we have established our Policy and Commitments on Water Management through a resolution of the Board of Directors in December 2022.
1 Water risks: Water risks related to water supply for current and future business continuity and the increasing rate of flooding from extreme weather associated with climate change
Policy and Commitments on Water Management
We strive to understand the impact of our business on water resources and sustainability in local communities and promote efforts on impact mitigation and value creation on local water sustainability.
- Identify water-related risks in areas around operational sites
- We strive to understand the water-related risks at operating sites using international risk assessment tools.
- We will develop and implement additional measures based on mitigation hierarchy3 for areas evaluated as high water-related risk areas.
- Restrict freshwater intake in high water stress4 areas
- We will limit freshwater intake where significant impact is expected on local water resources as a result of freshwater intake by our operating sites.
- Implement appropriate water management (water intake, usage, and drainage)
- We will strive to understand the status of water usage (water intake, drainage, usage) at our operating sites and promote 3R (reuse, reduce, recycle).
- We will implement appropriate treatment and wastewater management for produced water and other associated wastewater.
- Collaborate with stakeholders
- We will collaborate with stakeholders to promote sustainable use of local water resources.
3 Order of priority to avoid, reduce or minimize development impacts and then taking compensatory measures for remaining impacts.
4 A state of inconvenience in daily life caused by lack of water.
Water Risk Assessment and Identification of High-Water Stress Areas
Each year, we confirm if our operator project sites in Japan and overseas are located in high water stress5 areas by using Aqueduct, a water risk mapping tool developed by the World Resources Institute(WRI).
We have confirmed that, as of December 31, 2022, water stress levels are not high in our operator project sites, and there are no expectations of increased project costs as a result of water shortages.
Since local water risks are influenced by various factors and change over time, going forward we will continue to identify water risks, and if we find water risk to be too high, we will plan and implement additional measures according to the mitigation hierarchy.
5 Water stress: The amount of water resources available per person, used as an index for assessing the scarcity of water supply versus demand
Efficient Use of Freshwater Resources
As one of the resources we utilize in our business operations, we recognize freshwater intake to be a major issue in our water management. We have been working to reduce our impact on water resources by managing the water intake of our operator projects in Japan and overseas, and the discharge of produced water arising from oil and natural gas production. Our operator project sites use tap water, industrial water, and groundwater as coolants.
In FY2022, the volume of freshwater used across the Group totaled 2,257 thousand cubic meters.
In addition to using groundwater for normal cooling and drilling operations in Japan, we also use it for melting snow in winter. We are also taking action to reduce our freshwater consumption, including by adopting a circulating system for cooling water, and equipping snow-melting systems with automatic start and shutoff mechanisms.
At the Ichthys LNG onshore processing plant, we conduct investigations into freshwater use with the aim of reducing consumption. The findings of these investigations are being used to study the feasibility of cost-effective approaches for reducing freshwater consumption by reusing water, such as treated wastewater from processing as well as wastewater and condensed steam from power generation facilities.
Use of Seawater
Instead of freshwater, the Ichthys LNG offshore production facilities use seawater for cooling, and the Naoetsu LNG Terminal uses it for heat exchange in the vaporizer. Mandatory checks of seawater temperature and residual chlorine levels ensure that the marine environment will not be harmed, and that relevant laws and international guidelines are met before the used seawater is discharged back into the sea.
Produced water from our oil and natural gas projects is reinjected underground or discharged as wastewater after being confirmed to comply with the effluent standards in local and international guidelines.
In FY2022, 60% of the total produced water (approximately 1.33 million cubic meters) was reinjected, while the remainder was discharged into rivers or seas after being appropriately treated.
Development of Effluent Water Treatment Technology
From FY2015 to FY2017, in collaboration with Chiyoda Corporation and METAWATER, and with the support of Japan Organization for Metals and Energy Security (JOGMEC), we conducted a pilot project at our Sotoasahikawa plant of the Akita Field Office to test a produced water treatment technology using ceramic membrane filtration. This technology is expected to further reduce the environmental impacts of water discharges from crude oil production. A joint follow-up study with JOGMEC was launched in FY2018, and a pilot test for commercial use of this technology is currently ongoing. To date, the test has confirmed sufficient capacity to treat the water effluent to the discharge standard for rivers as specified by Akita Prefecture.
As of March 31, 2022, we achieved a total operation time of 23,123 hours, constructed a produced water processing facility, and have continued to operate without incident or occupational injury throughout the entire operating period (approximately seven and a half years).
The study was concluded in March 2023.