Water is a natural resource that is needed by humans for many purposes. Therefore, the Company cannot be separated from water needs. Company uses water for various purposes, namely the production process and many supporting activities. [103-1, 303-1]
The need for water does not make the company wasteful in water consumption. Given the increasingly limited availability of water, especially clean water on earth, the company is committed to using water wisely and maintaining the sustainability of its sources. Some of the efforts made by the company include:
1. Minimizing the use of groundwater
By not taking water from the ground, the Company contributes to protecting the environment by not lowering the water level, not reducing the available water volume and not changing the ability of ecosystem functions. [103-3]
2. Management of Water Treatment Plant (WTP)
The company fulfills the need for clean water for offices and corporate housing from rivers that are managed through a Water Treatment Plant (WTP) or Water Treatment Plant, as well as from springs. During 2020, the volume of water use achieved 1.39 million m3 , a decrease of 28.52% compared to the previous year, which was recorded at 1.95 million m3 . Measurements are made by the method of installing a flow meter at the raw water inlet that enters the WTP which automatically reads the water cubication consumption. [103-3, 303-1]
During the operation, PTBA produces wastewater based on the consumption of water sourced from these rivers and springs. Furthermore, the wastewater is recycled into clean water so that it can be reused. Recycling is carried out by innovating by making WTP Limoa which functions to manage mine water into clean water. Implementation of this recycling is able to reduce the consumption of clean water from rivers and springs. The policy to recycle wastewater is carried out by referring to Company policy, such as water efficiency and reduction of water pollutant loads facilities. [103-1, 103-2] [6.d.2)] During the reporting year, the volume of recycled water that was reused was recorded at 22,250 m3 , decreased compared to the previous year, which was recorded at 89,880 m3 . The decrease in the volume of recycled water is influenced by availability of water source that is used, which is mine runoff (rainwater) [103-3, 303-1]. Water reclamation program through recycle through recycle of effluents/mine water into clean water is not included in general practice, because the water source used is mine runoff (rainwater), generally using river water. [103-3]
In its production process PTBA generates effluents. Acid Mine Water (AAT) is a natural phenomenon, where rocks containing sulfur (acidic rocks) are oxidized in open air, and when exposed to water it becomes acidic water. PTBA has a holistic mine water management conception, beginning with geochemical investigations of rock through modeling to facilitate the characterization of rocks with the PAF (Potential Acid Forming) and NAF (Non Acid Forming) categories. PAF & NAF material handling is carried out systematically in the stockpile area, so that it can be ascertained that the potential for the formation of acidic water due to PAF oxidation does not occur. This is an effort to mitigate/prevent the formation of acid mine drainage in the stockpile area. The company has specific procedures, which regulate the disposal of acidic rock and acid mine drainage. Purpose of those management activities is to fulfil the water taken from mining are to always comply with environmental quality standard. [103- 1, 103-2, 303-1, 303-2]
Initiatives to restore acid mine drainage are carried out through active treatment in settling ponds and passive treatment in a swamp (wetland) where heavy metal absorbent plants are grown as a phytoremediation agent. Acid mine drainage is treated by PTBA through active treatment in mud settling ponds and passive treatment in a swamp (wetland) where heavy metal absorbent plants are grown. The active treatment is carried out by neutralizing acidic water by using quicklime to reduce acidity in the water and adding alum or curiflock to reduce TSS levels so that these parameters can meet environmental quality standards. Whereas in the passive treatment, runoff water is channeled into the wetland covering an area of 1.5 to 2 ha, while the wetland locations are spread over 3 IUPs (IUP TAL, IUP MTB and IUP Banko Barat). Types of vegetation that grow in wetland ponds are water jasmine (Echinodorus palifolius), Kiambang (Salvania natans), Thypaangustifolia, Eleocharis Dulcis, Lonkida, and Vetiveria zizanoides which have the ability to Hyperaccumulator dissolved metals in water. Furthermore, the water that has treatment and meets Environmental Quality Standards (BML) is in accordance with the Regulation of South Sumatera No. 8 of 2012 will flow into the Enim River. [103-1, 303-2]
Initiatives to prevent pollution and reduce environmental load on surface water are carried out by the Company by building a closed water treatment system. With this system, any run-off water from the mine is channeled to mud settling ponds as part of mine reclamation activities for processing. All water streamed from the mining area is tested every month to ensure its quality is in accordance with applicable Water Quality Standards. The reduction in environmental load is also achieved by reducing the waste content in the wastewater. In the Company’s operational process, reduction in pollution load per year, such as turbidity/Total Suspended Solid (TSS) averaging 2,491 Kg/ ton of coal, Iron (Fe) an average of 0.059 Kg/ton of coal, and an average of manganese (Mn) 0.107 Kg/ton of coal by applying the innovative wetland method. With this initiative, there is no record of any water bodies being affected by the release or overflow of water from the Company. [103-3, 306-5, 303-2]
The volume of wastewater generated by PTBA during the reporting year is presented in the following table: [103-3, 306-1, 306-2, 303-2]
PTBA does not yet have a water recycling mechanism. The priority of conserving water resources is carried out through efficient use of water, such as:
• Use of environmentally friendly technology that saves water usage;
• Campaign to increase employee awareness to have efficient behavior in using the water. [303-3]
The following shows amount of water taken, released and consumed by PTBA during the reporting year. [303-3, 303-4, 303-5]
"Communal Waste Water Treatment Plant (WWTP) Dusun Tanjung Village"
The construction of the communal WWTP is the alignment of Sustainable Development Goals year 2030 in relation to the sustainable economic, environment and social empowerment. The program is an innovative way to empower the community in reducing domestic waste water pollution in Dusun Tanjung so as to improve the healthy lifestyle of the people in Dusun Tanjung.
PTBA also helps the community in applying systematically, integrated and collectively managed domestic waste. Replacing the previous system in which domestic waste was managed by conventional septic tank in every house and some of the waste is directly flowed into the river, the new domestic waste management is healthier for the environment.
PT Bukit Asam Tbk is a pioneer in the construction of communal WWTP for the community with cost-effective way in Dusun Tanjung, in collaboration with the Housing and Settlement Service of Muara Enim Regency. This is more cost-effective because there is no need for annual spending on additional management (draining of waste) in the communal WWTP. The other innovation is the change of WWTP sub-system which operates without a pump to channel domestic waste to the WWTP. The process of channeling the domestic waste is entirely carried out by gravity, this can occur because of the topography and the location of the houses sloping to one point and the location of this point is used as the location of the WWTP.
The sub-system changes can also be seen in the community lifestyle in Dusun Tanjung Village. Prior to the construction of the communal WWTP, the domestic waste management was not standardized. That compelled the company to participate in assisting the government in realizing a better community sanitation.
The program also drives changes in the value chain. In the supplier’s perspective, in case of the community building the communal WWTP independently with funds from the company, the supplier can get additional income and portfolio in the construction of the WWTP. In the company’s perspective as the producer, the program can increase the company image as a company that cares about the environment. In the community’s perspective as the consumer, the community experienced behavioral changes as the awareness of hygiene and domestic waste management increased.
The environmental improvement generated is the reduction of BOD waste up to 94% or as much as 2 tons BOD per year. The program also managed to reduce cost valued at IDR44,1 million per year, by eliminating the cost of draining the conventional septic tank with volume of 147 m3 per year.
Water management treatment in Bukit Asam have also received ISO 14001: 2015 certification recognition.