Produced water will be treated and reinjected back into the reservoirs for pressure support and ensure reservoir void age replacement. Produced water reinjection presents environmental benefits as it shall significantly reduce treated water volumes that have to be disposed into the environment and reduce the water volumes that must be abstracted from the lake to sustain reservoir pressure.

Waste that cannot be used as produced water shall be collected and hauled off site by licensed waste management contractors, for treatment at licensed waste management facilities using wastewater treatment technologies including, ultra-filtration and reverse osmosis to meet national permissible wastewater discharge standards before its discharged into the environment or used for dust suppression.

Waste produced from drilling operations is mainly composed of mud cuttings which are a mixture of rock cuttings and drilling fluid that contains additives like bentonite and barite which are used in the drilling process. In Uganda, Water Based Mud (WBM) has been used most often because it is more environmentally friendly than Oil Based Mud (OBM).

During the exploration phase, waste generated from the well sites was stored at designated consolidation sites where the waste was containerised and monitored. So far, no accidents have been reported regarding waste generated from various exploration and production activities, as well as base camps.

As of January 2023, NEMA had licensed EnviroServ and National Enterprise Company (NEC) to handle waste at different levels namely, transportation, treatment, and disposal. Previous containerised waste has been transferred to EnviroServ for treatment and disposal. In addition, the requisite legislation for waste management has been updated.

The Tilenga Development Project presents a number of potential direct, indirect and induced impacts within the project area of influence. The impacts were categorised in 6 major areas that included;

1. Physical environment impacts related to the non-living environment, including air quality and climate; noise and vibration; geology and soils, hydrogeology; surface water; landscape and visual, and waste.
2. Ecological/ biodiversity impacts related to relevant sensitive receptors within the Project’s Area of
3. Social impacts  related   to   people,communities, and livelihoods (including socioeconomics; health and safety; archaeology and cultural heritage; and ecosystem services).
4. Unplanned events,  activities   that are not expected to occur during the Project’s normal activities, such as emergencies, accidents, and incidents.
5. Potential Cumulative effects, effects of the project together with other developments within the project’s area of influence
6. Potential transboundary impacts: those that could extend to neighbouring countries, but are not global in nature

These impacts were adequately assessed and evaluated, and appropriate mitigation measures were identified and proposed to minimize such impacts. The selection of mitigation measures considered the standard mitigation hierarchy, whereby preference was given to avoiding impacts altogether and subsequently to minimising the impact, repairing its effects, and/ or offsetting the impact through actions in other areas. In addition, the project Front-End Engineering Design incorporated embedded mitigation measures into the designs of the Project to further reduce the impacts associated with the Project. The project has also developed and is implementing an Environment and Social Management Plan (ESMP). The ESMP outlines the project phases, activity potential impact description, mitigation and enhancement measures, monitoring mechanisms, performance indicators and associated costs. It further designates the roles and responsibilities of the different entities that shall be involved in implementation of mitigation measures and monitoring. Numerous baseline studies have been undertaken and continue to be undertaken to collect pre project data on metrics (social economic, wildlife, air, and waste quality) that shall continue to be monitored during project implementation over the years. The metrics shall be used to evaluate any changes resulting from the project and the effectiveness of suggested mitigation measures.

Before commencement of any activity, a comprehensive Environment and Social Impact Assessments (ESIA) is undertaken to identify the social and environmental impacts of a project as well as the measures to reduce the impacts and maximize the benefits.

ESIAs are undertaken by the IOCs in consultation with the PAU, National Environment Management Authority (NEMA) and local communities. The ESIA public hearings for the Tilenga and Kingfisher projects were held in November 2018 and June 2019, while those for the East Africa Crude Oil Pipeline were held in October 2019 in Kakumiro, Mubende and Rakai districts.

All the projects have received ESIA certification from the NEMA. The Tilenga Development Project ESIA was approved in April 2019, Kingfisher Project in March 2020 while the EACOP ESIA was approved in November 2019 (Tanzania section) and November 2020 (Uganda section).

As highlighted earlier, the PAU also monitors activities in the field to ensure compliance and reduce the risk of any potential negative impacts on the environment.