Water and abandoned metal mines Environment Act target delivery plan
Statutory Environment Act target
Halve the length of rivers polluted by harmful metals from abandoned metal mines by 2038, against a baseline of 1,491km.
Interim target
Construct 8 mine water treatment schemes and 20 diffuse interventions to control inputs of target substances to rivers, and complete 55 catchment studies by December 2030.
Rationale for the interim target: why and how it will progress delivery of the Environment Act target
The interim target uses a construction metric instead of an output (kilometres) metric, as used for the statutory target, to ensure mine water treatment schemes and diffuse interventions are being completed at the rate necessary to achieve the statutory target.
The interim target will deliver 8 mine water treatment schemes and 20 diffuse interventions by December 2030. This sets an achievable construction trajectory to the statutory target. The interim target also has an additional element to complete 55 catchment studies by December 2030.
Catchment studies are critical for programme planning and identifying priority sources of pollution requiring remediation. They also inform decisions on where to construct schemes, enabling feasibility studies for scheme design and construction to progress. Not all catchment studies will meet the criteria for progression into feasibility study, and subsequently not all feasibility studies will pass into design. That is why we need more catchment and feasibility studies than the number of schemes which will ultimately be constructed, and why front-loading catchment studies within the interim target period is important in de-risking long-term delivery.
We expect to meet the statutory target by delivering the programme using the mechanisms described in this plan. All mine water treatment schemes and diffuse interventions (collectively known as remediation measures) will reduce input of harmful metals from mine water and contaminated mine wastes and sediments respectively. These measures will thereby decrease the metal concentrations from abandoned metal mines in the relevant polluted river.
However, some rivers have higher background levels of metal (compared to the Environmental Quality Standards (EQS)) due to the mineralised underlying geology in those areas. This means it is technically infeasible to decrease the concentrations of some harmful metals to the EQS levels required for the statutory target. As a result, this can impact the measurement of our progress towards the statutory target. A Defra and Environment Agency (EA) working group is investigating these issues to inform how these are accounted for when assessing and reporting on progress towards the statutory target. We expect to resolve these issues by 2030.
Delivery measures
The following delivery measures detail the sequentially dependent stages required for the delivery of a remediation measure. Diffuse interventions have a shorter delivery pipeline but must still proceed through the same sequentially dependent stages as a mine water treatment scheme, which has a longer 5-to-7-year timeline.
Table 1: Summary of delivery measures and supporting evidence for the water and abandoned metal mines programme
| Delivery measure | Description | Estimated contribution to the interim targets | Evidence of impact | Responsible | Status |
|---|---|---|---|---|---|
| Catchment and verification monitoring studies | Catchment studies identify priority sources of metal pollution requiring remediation measures. Verification monitoring studies evaluate water quality improvements after remediation measures become operational. This is essential for reporting on progress against the statutory target. We must complete 55 catchment studies to stay on track to meet the statutory target. |
High | Catchment studies are the fundamental first stage for the construction of new remediation measures. There is high confidence in the information provided by these studies to inform the decision-making on whether to proceed onto the next stage (feasibility). | EA | In delivery |
| Feasibility and design studies | Feasibility studies investigate feasibility of construction, cost benefit of construction, and make recommendations on potential scheme locations. Design studies develop options for design of schemes and apply for necessary planning and regulatory permissions. We estimate 40 feasibility studies will be completed by 2030 (subject to successful outcomes in catchment studies). |
High | Feasibility studies are an essential second stage in the development of a new mine water treatment scheme or diffuse intervention. Outcome from feasibility stage provides determination on whether a scheme will proceed onto the design stage, as not all locations will meet the criteria of feasibility of construction. |
Mining Remediation Authority (MRA) | In delivery |
| Construction delivery | We will need to construct 8 mine water treatment schemes and 20 diffuse interventions by 2030 for the EIP 2025 interim target, and to remain on track for the statutory target. For the statutory target we will need approximately 30 to 40 mine water treatment schemes and approximately 40 diffuse interventions. |
High | It is the constructed scheme which ultimately decreases pollution levels in rivers by reducing the input of harmful metals and improving river water quality. Constructions are bespoke in design according to local elements and have varying outputs of length of river improved. | MRA | In delivery |
| Operation and maintenance | Operation and maintenance of all remediation schemes - this includes legacy (pre EIP23) and new (built since EIP23) mine water treatment schemes and diffuse interventions, is required in perpetuity to prevent scheme deterioration and maintain the improvement in river water quality which contributes towards the statutory target. | High | Schemes must be operating to contribute towards targets. | MRA | In delivery |
| Research and development (R&D) | We will investigate treatment and delivery options to decrease whole lifecycle costs of remediation measures. We plan to complete up to 20 R&D studies by 2030. |
High | R&D schemes investigate innovative treatment and delivery options. They are important to ensure the programme is always investigating and applying the best options in line with use of public funds. | MRA | In delivery |
Key milestones
To reach the interim target we need to construct 8 mine water treatment schemes and 20 diffuse interventions to control inputs of target substance into rivers and complete 55 catchment studies by 2030. To date 2 mine water treatment schemes have been constructed, and 5 catchment studies have been completed, and the target of 20 diffuse interventions has been delivered. For the coming years we have the following milestones planned:
Overview of milestones to reach the interim target:
- Water and Abandoned Metal Mines (WAMM) Programme completes construction of the remaining 6 mine water treatment schemes required for the interim target by December 2030.
- EA completes the remaining 50 catchment studies by the interim target of December 2030.
Illustrative trajectory
Table 2: Trajectory towards EIP 2025 interim target under the WAMM delivery plan
| Delivery measure | EIP 2023 to EIP 2025 | 2026 | 2027 | 2028 | 2029 | 2030 | Number to be completed by 2030 |
|---|---|---|---|---|---|---|---|
| Mine water treatment schemes (MWTS) constructed and planned | 2 | 1 | 1 | 1 | 1 | 2 | 8 |
| Names of schemes | Coombe and Nent Haggs | To be confirmed – subject to results of studies | To be confirmed – subject to results of studies | To be confirmed – subject to results of studies | To be confirmed – subject to results of studies | (2 MWTS) To be confirmed – subject to results of studies | 8 |
| Diffuse interventions constructed | 20 | 0 | 0 | 0 | 0 | 0 | 20 |
| Catchment studies completed and to be completed | 5 (delivered after December 2025) | 5 | 8 | 10 | 12 | 15 | 55 |
| Feasibility studies to be completed per year | Not applicable | 2 | 5 | 9 | 11 | 13 | 40 |
| Design studies to be completed per year | Not applicable | 2 | 3 | 3 | 4 | 4 | 16 |
Notes about Table 2
- Note 1: Figures in the EIP23 to EIP 2025 column refer to completed schemes.
- Note 2: Future projects may be subject to change for technical or practical reasons; current numbers are estimates only and will be re-evaluated in future planning processes.
- Note 3: Studies take about 15 to 24 months to complete. Not all studies will pass criteria for progress into next stage. Studies completed between EIP 2023 and EIP 2025 are not counted as contributing to the new metric included in the EIP 2025 interim target.
We anticipate that to reach the 2038 statutory target, we will need approximately 30 to 40 mine water treatment schemes and approximately 40 diffuse interventions in total.
We expect to deliver around 3 treatment schemes and 3 diffuse interventions per year after 2030. We cannot finalise the exact delivery pathway and location of schemes until after we have completed the 55 catchment studies required for the interim target. These will provide essential information to identify and prioritise the locations for the remaining remediation measures.
Monitoring and evaluation summary
Our metric for delivering the interim target counts the number of mine water treatment schemes and diffuse interventions that have been constructed and the number of catchment studies completed.
To be counted towards the interim target, mine water treatment schemes must treat at least 10% of the total flow requiring treatment and be predicted to measurably decrease metal concentrations in the receiving watercourse – as assessed by the catchment study.
Diffuse interventions are counted as contributing to the interim target once construction is completed. The WAMM Programme Board assesses whether a scheme or diffuse intervention counts towards the interim target through transparent decision-making and a brief report on each project. WAMM Board meetings are scheduled every quarter.
The metric for assessing achievement of the statutory target is calculated by measuring the length of rivers and estuaries polluted by the target substances from abandoned metal mines. This length will be compared with the 2022 baseline length determined by the EA, as set out in their report: Abandoned metal mines in England: baseline length of rivers and estuaries polluted by harmful metals. Monitoring to assess compliance with the statutory target will be carried out during 2038 and reported by 1 February 2040.
The concentrations of target substances in rivers are measured, and pollution is assessed in accordance with the approach set out in The Water Framework Directive (Standards and Classification) Directions (England and Wales) 2015.
The frequency and detail of reporting on and tracking our progress against the baseline towards the statutory target has yet to be agreed. The potential options for a robust reporting approach will be reviewed during 2026 before the WAMM Board decides which approach should be adopted.