The Ministry of Environment and Energy (Ministerio de Ambiente y Energía, “MAE”), through the Environmental and Social Remediation Program (Programa de Reparación Ambiental y Social, “PRAS”), announced, through Circular No. MAE-SCA-2026-0007-CIR dated August 5, 2026, the “Guide for the Remediation and Restoration of Pollution Sources from Mining Activities,” an instrument intended to identify pollution sources associated with mining infrastructure and establish technical guidelines for their remediation, restoration, monitoring and follow-up.
The Guide is aligned with PRAS objectives to identify and prioritize pollution sources and environmental liabilities, design and implement comprehensive remediation processes, and develop regulatory and methodological tools for environmental control. Based on the information recorded by PRAS, the Environmental Control Directorate (Dirección de Control Ambiental) may require mineral rights holders to implement environmental remediation and restoration measures in affected areas.
- Scope and objectives
The Guide is intended for the remediation and restoration of areas affected by pollution sources identified in regulated, unregulated and registered mining concessions and mineral processing plants that have not undergone technical closure. The proposed measures must be coordinated with the Environmental Management Plan when an environmental administrative authorization is in place and, as applicable, with the Action Plan or the Mine Closure and Abandonment Plan approved by the competent authority.
Its overall objective is to establish guidance applicable to areas affected by mining-related pollution in regulated or unregulated, registered and expired concessions, to assist operators in submitting to the Competent Environmental Authority remediation alternatives intended to ensure physical and chemical stability, together with subsequent monitoring and follow-up mechanisms. Its specific objectives are to identify mining infrastructure and pollution sources, determine applicable remediation technologies, establish activities to be carried out before implementation, and propose monitoring and follow-up methods.
- Legal framework and responsibilities
The Guide is based on constitutional provisions recognizing the right to a healthy environment, the right of nature to restoration, and the obligation to adopt effective mechanisms in response to serious or permanent environmental impacts, including those resulting from the exploitation of non-renewable natural resources. It also reflects the national priority of conserving soil and preventing its degradation through pollution, desertification and erosion.
The Organic Environmental Code (Código Orgánico del Ambiente, “COAM”) incorporates the principle of direct environmental responsibility and the “polluter pays” principle: any person who causes pollution must include in its costs the measures required for prevention, reduction and comprehensive remediation, as well as any applicable indemnification, compensation and penalties. The operator of a project, work or activity must prevent, avoid, reduce and, where possible, eliminate environmental impacts and risks and, if an environmental impact occurs, establish the mechanisms necessary for restoration.
The Mining Law (Ley de Minería) provides that the sector must be managed in accordance with the principles of sustainability, precaution, prevention and efficiency; recognizes as mineral rights, among others, concessions, contracts, licenses, permits and authorizations for mineral processing, smelting and refining plants; and requires prior administrative acts for the conduct of mining activities, including an environmental license and the pronouncement of the Single Water Authority (Autoridad Única del Agua) in the cases provided for by law. In addition, holders of mining concessions and permits must use methods and techniques that minimize damage to soil, the environment, natural or cultural heritage, neighboring concessions and third parties, and must compensate for any resulting loss or damage.
The Environmental Regulations for Mining Activities (Reglamento Ambiental de Actividades Mineras, “RAAM”) impose civil, criminal and administrative liability on mineral rights holders for their activities and operations, including those carried out by their contractors and subcontractors. The holder is responsible for preventing, avoiding and comprehensively remediating environmental impacts or damage and for maintaining a permanent environmental control system, without prejudice to the joint and several liability of contractors and subcontractors. Contractors and subcontractors, as well as associates and authorized operators of mineral processing, smelting or refining plants, must also directly implement environmental prevention, remediation and control mechanisms.
- Action Plan and fifteen-day deadline
Whenever a pollution source arising from the activities of a mineral rights holder is identified, the holder must submit an Action Plan containing the corresponding measures to the Competent Environmental Authority. If monitoring and control mechanisms detect non-compliance with the Environmental Management Plan or applicable environmental regulations, the holder must submit the Action Plan within a maximum period of fifteen days from notification. The Action Plan must be approved by the Competent Environmental Authority and will be subject to control and follow-up in accordance with its schedule.
Mineral rights holders are responsible for executing and implementing Environmental Management Plans and must observe the precautionary principle, such that a lack of scientific evidence does not justify a failure to adopt preventive measures when potential environmental damage is reasonably suspected. A mineral rights holder will not be liable for environmental damage caused by activities unrelated to its mining operations if it demonstrates, through documentary and technical evidence, that such damage was not caused by it; in addition, it must report illegal mining activities.
- Relevant definitions and elements
The Guide distinguishes construction materials mining, non-metallic mining and metallic mining and, by extraction method, underground mining, open-pit mining and alluvial placer mining. It also identifies as relevant elements or facilities mine openings, quarries, galleries, pits, waste rock dumps, alluvial workings, sedimentation and sludge ponds, mineral processing plants, and tailings storage facilities or tailings dams. With respect to aggregates and stone materials, it reiterates the authority of municipal governments to regulate, authorize and control extraction from riverbeds, lakes, seashores and quarries within their jurisdictions.
A pollution source is an anthropogenic activity or infrastructure that contains, emits or disperses pollutants capable of causing adverse effects or negative alterations to one or more ecosystem components and causing, or potentially causing, environmental damage or liabilities. Pollution sources may be active or inactive depending on their operational status.
- Mining pollution sources
The Guide identifies as pollution sources, among others, mine openings without control or closure measures and mine drainage discharged without prior analysis or treatment. The latter includes mine water, wastewater and acid drainage resulting from the weathering and oxidation of metal sulfides when released at an acidic pH without treatment.
It also addresses waste rock dumps without control or closure measures that may generate acid drainage; abandoned mining areas or mining areas without control measures that cause groundwater emergence, direct untreated discharges to water bodies or alterations to watercourses; and landslides associated with inadequate slope configurations or the interaction of slopes with precipitation.
Ponds that store mine water, mineral processing water or wash water constitute pollution sources when they experience seepage or discharge to soil or water bodies without adequate treatment. Tailings or tailings dams without control or closure measures are considered particularly relevant due to their potentially hazardous content and the risks of overflow, seepage or collapse; the Guide states that hazardous waste must be managed by duly qualified environmental waste managers.
The Guide also includes abandoned infrastructure that has been in contact with hazardous substances, oxidized metal structures, potential mercury use in artisanal and small-scale mining, and dumps or hazardous-waste storage areas lacking adequate containment and impermeabilization measures.
- Preconditions for remediation
The measures set out in the Guide are intended for the technical closure and remediation of existing pollution sources, not for the commencement of new extractive activities. Their implementation is subject to approval by the Competent Environmental Authority under the corresponding Action Plan or Mine Closure and Abandonment Plan. The implementation of unauthorized measures may give rise to the corresponding administrative sanctioning proceedings.
Before selecting a remediation technology, the pollution source must be characterized in detail through information gathering, identification and description of the source, delineation of its perimeter and direct and indirect areas of influence, physical and chemical characterization, impact assessment, identification of technical risks, and determination of the areas or volumes to be remediated.
The Guide also provides for a social assessment through semi-structured interviews with key stakeholders. The information should identify the landowner, the origin, type and magnitude of the impact, risks affecting remediation, and input for monitoring and follow-up, and must be cross-checked against official information. This stage also serves to manage access and presence permits, public-road occupancy permits, easements or other authorizations necessary to access the area before the intervention begins.
- Mine openings and mine drainage
For mine openings with drainage, remediation is intended to restore the landscape, prevent acid drainage, avoid structural collapse, and restrict access by people and animals. The stability of underground workings must first be assessed through geomechanical and geophysical studies; depending on the technical conditions identified, measures may include reinforced or sprayed concrete, rock bolts, steel sets or arches, waste-rock backfill, or hydraulic backfill.
The closure or sealing method must be selected based on rock quality, faults and fractures, the number of levels and the depth of the workings. Alternatives include watertight or zero-discharge sealing, which confines water through a concrete plug, and air-blocking sealing, which allows water to discharge while limiting oxygen ingress and sulfide oxidation. For mine openings without drainage, the Guide proposes preventing access through a concrete wall and, where appropriate, the placement of waste rock.
- Quarries and mining areas without closure measures
Quarry remediation must be supported by geological, hydrogeological, geotechnical and environmental information obtained in situ and through laboratory testing. The selection of measures should take into account available technical and financial resources, the magnitude of the impact and the urgency of the issue. Measures are primarily aimed at physical stabilization and revegetation.
Stabilization may include modifying slope geometry, reducing slope inclination, removing weight from the slope crest, adding weight at the toe, configuring benches and berms, installing surface and deep drainage, anchors and piles, and using various types of supporting, retaining or facing walls. Subsequent rehabilitation may include the placement of organic or fertile soil and revegetation with species characteristic of the area.
- Waste rock dumps
Remediation of waste rock dumps must consider stability, slope, soil type, impermeabilization, and proximity to water bodies and populated areas. The material must be physically, chemically and mineralogically characterized, including parameters such as specific gravity, cohesion and internal friction angle.
Alternatives include benching, gabion walls, gravity walls or crib walls, which may be combined according to site characteristics. Structures must also be provided to drain surface water and prevent runoff and erosion. Encapsulation may include layers of clay material, limestone and topsoil followed by revegetation, with the specific design determined by the material composition, topography, climate, vegetation and landscape.
- Alluvial mining and watercourse restoration
Alluvial mining must preserve the natural course of drainage and prevent alterations caused by sediment. To remediate affected areas, water and sediment must be characterized in accordance with the minimum parameters set out in Annex 1 and compared against the maximum permissible limits established under applicable regulations. The Guide itself notes that Ecuador currently has no specific regulations for sediments and recommends, in the interim, applying the standards applicable to the soil subcomponent.
Depending on the results, treatment may include physical processes such as screening and sedimentation, physicochemical flocculation and coagulation, secondary treatment using wetlands or bacteria, and passive dispersed alkaline substrate methods to raise pH and precipitate metals. Technologies may be combined and must be selected based on the physicochemical characterization of the water.
River or watercourse restoration should seek to recover the river’s natural dynamics, a stable and flexible morphology, and habitat diversity. Before intervention, the relevant reach must be analyzed within its watershed and the existence of other contributing impacts must be assessed. Measures may include channel widening, erosion control through transverse structures, bank stabilization, controlled deepening and the placement of riparian vegetation.
- Ponds and water treatment
The treatment measures provided in the Guide may be adapted to tailings-pond water, mine water and water from alluvial mining, depending on their characterization. Following treatment, where infrastructure closure is required, the storage infrastructure must be removed, materials must be classified by waste type and delivered to the corresponding environmental waste manager or reused where appropriate. The area may be backfilled, graded and revegetated in an effort to restore its original physical and morphological characteristics or preserve existing landscape conditions.
- Tailings and tailings dams
The Guide classifies tailings storage facilities as high-risk facilities due to their composition and the potential consequences of failures or seepage. Their design and remediation must consider the geotechnical conditions of the area, existing discontinuities, geological vulnerability, impermeabilization, proximity to water bodies and populated areas, and any other requirements imposed by the competent authority.
In situ remediation requires physical and chemical characterization of the tailings, construction or improvement of perimeter drainage ditches, profiling and compaction of walls or dikes to ensure stability, and encapsulation through covers selected according to the tailings, available materials, impoundment configuration, topography, climate, vegetation and landscape, followed by revegetation.
- Vegetation restoration and complementary measures
Once remediation measures have been implemented, the operator must continue with vegetation restoration. The Guide distinguishes active restoration, involving human intervention to recover ecological functions and accelerate regeneration, from passive restoration, which allows natural recovery after the barriers preventing ecosystem succession have been removed. In addition to revegetating with species characteristic of the area, the activities approved under the Affected Areas Rehabilitation Plan or the Mine Closure and Abandonment Plan must be implemented, where applicable.
General complementary measures include risk signage, closure of access routes using berms, trenches, walls, rockfill embankments, mesh or fencing, inventorying and dismantling facilities, de-energization, demolition, and classification of materials for management according to their hazardous or non-hazardous nature. The operator must also include in the proposed Action Plan or Mine Closure and Abandonment Plan a list of the machinery and equipment to be used, including identifying information, for approval by the competent authority.
- Social monitoring
Post-remediation monitoring must verify the physical and chemical stability of the remediated pollution source and long-term biophysical variables, establishing the location and number of monitoring points, monitoring frequency and total duration. With respect to social monitoring, the Guide recommends involving landowners and nearby communities identified during the initial interviews. If social stakeholders are willing to participate in monitoring and follow-up, their participation may be coordinated; otherwise, monitoring will be carried out by the operator.
Social monitoring seeks to promote transparency and participation, enable early detection of risks or non-compliance, assess progress, build trust and shared responsibility, legitimize implemented measures, and incorporate local knowledge. The Competent Authority may also provide training on applicable environmental regulations when requested by key stakeholders.
- Physical, chemical and biotic monitoring
For physical-stability monitoring, procedure manuals must be prepared and records maintained. As a basic measure, the Guide recommends visual inspections every six months for five years following remediation. For tailings storage facilities, waste rock dumps, quarries or areas where benching has been carried out, topographic or geodetic monitoring points, inclinometers, extensometers or piezometers may be installed, with monthly or quarterly monitoring for five years depending on the nature of the project.
Chemical monitoring covers the quality of surface water and groundwater, including monitoring points upstream and downstream of discharges, piezometers at waste rock dumps, tailings storage facilities and mine openings and, where applicable, soil or sediment sampling. Measurements must be conducted every six months for five years using parameters linked to the mineralogical and chemical characteristics of each site and verifying compliance with maximum permissible limits. All monitoring and sampling must be performed by laboratories accredited by the Ecuadorian Accreditation Service (Servicio de Acreditación Ecuatoriana, “SAE”), and both the laboratory and the parameters analyzed must be covered by such accreditation.
Biotic monitoring must assess erosion, cracks, vegetation establishment and the presence of metals in plant species. The first assessment must be conducted during the first month and thereafter quarterly or every six months for five years, depending on the progress of revegetation. The Guide clarifies that the five-year period is based on current regulations and may change as a result of future regulatory amendments.
- Technical parameters and annexes
Annex 1 establishes minimum physicochemical parameters for discharges and water quality in alluvial mining, open-pit mining, mine water, underground mining and discharges from mineral processing plants, as well as parameters for soil sampling. The Guide expressly states that these parameters are indicative and that, depending on the pollution source, the Competent Authority may require analysis of all parameters set out in the corresponding tables.
Annex 2 contains a key-stakeholder interview that collects information on the stakeholder, the landowner, the identification and characteristics of the pollution source, risks associated with remediation activities, recommendations and willingness to participate in or accompany monitoring and follow-up, and final observations.
- Penalties and legal consequences
The Guide does not establish an autonomous sanctions regime. However, it expressly states that remediation and restoration measures must be approved under the corresponding Action Plan or Mine Closure and Abandonment Plan and that the implementation of unauthorized measures may result in administrative sanctioning proceedings. In addition, the legal framework incorporated into the Guide reiterates the civil, criminal and administrative liability of mineral rights holders, as well as the liability of contractors and subcontractors and the principle of comprehensive remediation of environmental damage.
- Recommendations and applicability of the Guide
The document recommends incorporating social information into assessments and Action Plans, adapting remediation technologies to the nature of each pollution source, complying with monitoring frequencies, documenting results, and adopting corrective measures when failures are detected. It also promotes coordination among environmental authorities, local governments, communities and operators and provides that, once areas have been remediated and restored, their reuse may be evaluated through projects involving the community and landowners that contribute to local economic growth.
The Guide does not contain transitional or final provisions in a normative sense and does not establish its own effective date. Its application is expressly subject to the environmental regulations in force or any regulations that replace them; accordingly, the technologies, parameters and periods described in the Guide must be checked against the provisions in force when each plan is prepared and submitted for approval.
The Annexes form an integral part of the Agreement, which will remain in force indefinitely unless terminated upon six months’ notice. The English, French, and Spanish texts are equally authentic.
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This is a summary of legal developments of interest and therefore should not be construed as legal advice. Should you have any questions, please contact the AVL team.