The Combine operates in the foothills of the Talas Alatau, upstream of farmland in the Talas valley. Its environmental programme covers air emissions from the Chatkal complex, tailings from current and past production, and the quality of water leaving the industrial area.
Air
Since 2016 the Chatkal Chemical Smelting Complex has installed sulphur dioxide scrubbers and electrostatic precipitators to reduce emissions of sulphur dioxide and dust. Since 2018 a gas-capture unit has converted sulphur dioxide from the roaster into sulphuric acid. Emissions meet ISEZ standards.
Tailings
Tailings from current production are stored in tailings facilities at Sary-Bulak and Chatkal. Tailings from Soviet-era processing are held in the Chatkal Tailings Repository, for which the Combine and the ISEZ Government share responsibility. The embankment of the repository was raised and a drainage system installed in the late 2000s. Since 2018 the leases of the Sary-Bulak mines and the Chatkal complex have included tailings-safety conditions. See Tailings management.
Water
Surface water and monitoring wells below the workings and tailings dams are sampled for antimony and arsenic. The stability of the tailings dams is inspected by the Chatkal Placer Mining Inspectorate.
Mercury
The mercury recovery unit at Chatkal has been idle since 2019. Before it is refurbished, the Combine will sample the river below the complex and publish the baseline results, and a public hearing will be held in Sary-Bulak District on 26-11-2026.
Environmental fines
| Year | Fines paid (million som) | Main cause |
|---|---|---|
| 2019 | 3.4 | Break in the Sary-Bulak tailings pipeline (April); about 1,500 m³ of slurry reached the Sary-Bulak stream |
| 2020 | 2.6 | Clean-up of the 2019 spill; dust from the Chatkal roaster |
| 2021 | 1.2 | Exceedance of the arsenic limit in water below the Sary-Bulak tailings facility |
| 2022 | 0.9 | Dust from ore trucks on the Kara-Suu road |
| 2023 | 0.6 | Late filing of monitoring returns |
| 2024 | 0.5 | Arsenic exceedance in monitoring well MW-7, Chatkal |
| 2025 | 0.3 | Arsenic exceedance in monitoring well MW-7, Chatkal |
After the 2019 spill the tailings pipeline was replaced and fitted with pressure alarms, and in 2021 the Combine added sampling points below the Sary-Bulak tailings facility at the request of Kara-Suu village. Results are published in the Environmental Reports.
Environmental reports
Environmental Report 2025 [PDF, 0.8 MB] · Environmental Report 2024 [PDF, 0.8 MB]