Environmental Supportfor Mineral Extractionand Mining
2012- 13 and ESI has assisted several large UK aggregatesEnvironmental Impact companies with an audit of sites to determine work required to achieve compliance in advance of the new scheme.Assessments ESI supports sites that require permanent or temporary discharge consents (Environmental Permit) associated with mineral processing, site drainage or dewatering and designs the required mitigation measures to meet water quality conditions relating to silt settlement, hydrocarbons and other potential contaminants. Groundwater Control and Dewatering Planning constraints on lateral extensions for quarries has put increased pressure for deepening of existing sites below the water table. The energy cost of dewatering has become aMinimising the impact of a proposed development on the significant operational factor. ESI’s approach is focussed onsurrounding water environment is key to obtaining planning high efficiency with low operating costs. Environmentalpermission and maximising the available resource. ESI constraints, such as drawdown beneath sensitive receptors,supports the initial scoping requests, site investigations, are often critical to the feasibility of these schemes.environmental impact assessments and the environmentalstatement through an integrated understanding of all aspectsof the water environment encompassing groundwater, surfacewater and ecology.Clients have benefited from ESIs pragmatic and technicallyrobust approach and excellent working relationships withcontacts in all regions of the Environment Agency tonegotiate an effective outcome.Regulatory Permitting –Abstraction and Discharge ESI has extensive experience of handling all aspects of efficient dewatering and are currently developing and operating groundwater models of some of the largest dewatering schemes in the UK. ESI’s approach in all projects is to work closely with clients to determine the most appropriate level of assessment required, ensuring a cost effective solution is achieved in all cases.Many extractive developments require permits for abstractionlicensing and discharge consenting regimes. The UK WaterAct (2003) requires that many mineral dewateringprogrammes will require regulation and abstraction licences Groundwater Modellingthat should be renewed every 15 years. During renewal it is Groundwater models are the most effective and accuratelikely that a detailed Environmental Assessment is carried out. method of developing an understanding of how aquiferESI quickly and efficiently provides the regulators with systems behave and can be used to make predictions aboutapplications that meet their requirements. Transfer abstraction the system’s future behaviour. Specific questions that can belicences are due be introduced by the Environment Agency in addressed using a groundwater model include:
• How might a change in quarry depth impact on aquifer potential site after uses, including sustainable development, properties? aquaculture, water supply and treatment, flood alleviation and• What will the drawdown be beneath a sensitive receptor? nature conservation.• Will increased abstraction cause saline intrusion?• How might changes in abstraction affect groundwater quality? Waste Management andIn order to produce a groundwater model that can be usedas a reliable management tool, it is essential to base it on a Landfillcarefully worked conceptual model. ESI’s leading modellingcapability supports the selection of the right groundwatermodelling approach for the problem being faced.Site Water ManagementPlans and Water Audits ESI delivers a leading capability in landfill management. Under the Environmental Permitting (EP) Regulations (2010), the development of a conceptual model and the preparation of environmental risk assessments are required for all sites prior to a permit being issued. ESI provides support in preparing applications, reviewing permit conditions, evaluating the success of sites in achieving compliance criteria and negotiating permit issues withEffective control of the site water management system, regulatory authorities.including both groundwater and surface water components,is necessary to minimise costs and environmental risk duringthe operational phase and are included in the site plan. The Hydroecologyplans enable effective site management from the operationalthrough to the restoration phase and post closure. ESIcombines a practical approach with modelling of the sitewater balance to ensure adequate controls are in place tomanage the water efficiently and provide the resourcerequirements for mineral processing. ESI also offers a sitewater audit looking at the requirements for abstraction,discharge, processing and water treatment.Site RestorationESI regularly works with landscape architects and ecologiststo devise appropriate restoration proposals advising ongroundwater and surface water interactions and predictions Over the last decade ESI has been working with a range ofof the final water levels. Input is provided to the design of clients, particularly in the extractive and water industry, topractical water control measures such as outfall design. ESI develop more targeted and efficient ways of defining thehas very strong capabilities in the field of landfill permitting impact of industry on water sensitive ecology (hydro-and can provide information on integrating landfilling ecology). ESI works alongside other specialists (e.g. inopportunities into the proposed restoration design. ESI has aquatic ecology and hydrology) as part of a team to deliverworked with UK water companies to identify potential quarry clear answers to these problems. Assessments combine thevoids that could be used for water storage. ESI’s team broad, catchment scale, approach with a more detailed localmembers have undertaken research (funded through the understanding of the water level, flow and qualityAggregates Levy Sustainability Fund) into a wide range of requirements of the target habitat or species.
Flood Risk Assessments Water Quality and Contaminant Assessment Assessment of site discharge water quality will be required to ensure regulatory compliance; ESI can devise appropriate water quality monitoring procedures to provide the necessary data. Mitigation measures may be necessary to achieve water quality objectives and advice on silt settlement lagoons and water management facilities is provided. Site specific issues can include elevated metal concentrations and acid drainage related to weathering of metal sulphides. Control strategies can be devised in conjunction with the site management to minimise the impact on water quality from this source. ESI has an in depth knowledge of modelling contaminant fate and transport issues within the groundwater system.ESI offers a combined understanding of flood risk with theother groundwater and surface water issues on mineralextraction sites to provide optimal cost effective solutions. Newdevelopments will usually require a flood risk assessment Monitoring & Environmentalaccording to statutory requirements. A risk assessment is alsorecommended for existing sites when assessing the operational Data Managementimpact of flood risk to the site from adjacent water courses andrainfall run-off. An understanding of the flood risk posed by thesite to other receptors may be incorporated within the sitewater management plan to ensure site discharge is regulatedto acceptable levels and sufficient storage is available to copewith significant storm events.Water Supply and BoreholeDrilling ESI designs and implements suitable mitigation measures on major infrastructure projects including mines, tunnels and highways as well as aggregates and other quarrying schemes. Using quantitative assessment methods, alongside robust environmental monitoring, demonstrates the nature and extent of environmental impacts of such schemes on the water environment. ESI has expertise in designing hydrometric monitoring programs for both groundwater and surface water systems to achieve compliance with permit conditions. ESI provides customised environmental data management systems and services designed to enforce data quality andSite water supply is of key strategic importance in ensuring meet statistical analysis requirements. ESI can deliverthe site can continue to operate at all times including drought environmental data as spreadsheets, databases or webconditions. ESI offers both groundwater and surface water reports in the form of downloadable data and graphs.resource assessments from initial feasibility studies, throughdetailed inlet design or borehole testing, to permitnegotiations and obtaining the final abstraction licence. ESI Expert Witnessworks for many of the major UK water utility companies and Senior members of the consultancy team are able to providealso provides bespoke site specific water supply solutions for legal support, testimonies and act as Expert Witness’ inindustrial applications. support of public enquiries and court cases.
Environmental Support for MineralExtraction and MiningESI delivers technical, specialist services and advice to support mineral extraction and miningclients to develop their opportunities, whilst understanding and complying with environmentallegislation and managing their risks. ESI has a strong team of scientists with a good balancebetween pragmatic field experience and in-depth quantitative skills for analysis of field results.ESI has completed work on a large number of mineralextraction sites in a range of settings including, clay,sand and gravel pits, hard rock quarries, coal and Case Studiesmetalliferous mines in various UK and internationallocations. ESI provides ongoing support to sites withpractical advice on day to day water management Hydrogeological impactissues and monitoring reviews as well as input to longterm strategic plans. ESI also provides a high level assessment for a proposedgroundwater modelling capability, which is often acost effective way of proving environmental extensioncompliance. A detailed hydrogeological impact assessment of a proposed extension of a sand and gravel quarry near Lincoln wasThe range of services provided includes: carried out in support of a planning application. A significant• Environmental impact assessments body of data on the geology, hydrogeology and hydrology of• Regulatory permitting – water abstraction and discharge the site was collected and reviewed in order to develop a• Groundwater control and dewatering good conceptual understanding of the local flow systems. This• Groundwater modelling was used to identify the baseline hydrogeology of the area and• Site water management plans and water audits potential impacts on relevant receptors and the development of appropriate monitoring and mitigation measures.• Site restoration• Hydroecology A number of SSSI’s were identified in close proximity to the• Flood risk assessments site and were considered to be potentially sensitive to a• Waste management and landfill reduction in groundwater levels. To ensure that there would• Water supply and borehole drilling be no significant effect on these SSSI’s an extensive clay• Water quality and contaminant assessment bund was proposed as mitigation with a recharge trench to• Monitoring and environmental data Management ensure no short term impact during clay bund emplacement. The hydrogeological assessment was accepted by theUK Extractive Industry Environment Agency and planning permission was granted.Since 1996 ESI has developed an excellent understandingof the regulators changing requirements ensuring advice Groundwater modelling:on the exact scope of work required to achieve approval Lisheen Lead-Zinc Mine,for new plans and developments is delivered within agreedtimescales. A focussed approach of achieving compliance Irelandwhilst ensuring the methodologies developed and used are ESI developed a regional 3D transient MODFLOW model of thecost effective and reliable. ESI provides services to major Carboniferous Limestone aquifer to predict future impact ofproducers such as CEMEX, Tarmac and Hanson as well various abstraction regimes under differing recharge conditions.as specialist operators including Sibelco and Bathgate A four layer model was developed to represent this complexSilica Sands. multilayer aquifer system, drawing on extensive regional monitoring data and specific field investigations. SystematicInternational Mining and calibration of the model, initially to steady state conditions, and subsequently to transient conditions, was undertaken, along with a sensitivity analysis. The model was subsequently appliedMineral Extraction to the prediction of drawdown zone extent, resources assessment and the evaluation of water quality issues.ESI team members have extensive international experiencewithin Europe, Africa, Asia and the Middle East and havecompleted environmental impact assessments and due Al Kamil Coal Mine, Omandiligence work on open pit and underground operations. A detailed field investigation was designed and implementedProjects have included coal mines and metaliferous mines, using borehole drilling, pumping tests, packer tests,large scale aggregate extraction, cement production and hydrochemical sampling and analysis to characterise criticaloil refineries. ESI offers the supervision of field data hydrogeological parameters as the basis for dewateringcollection, combined with detailed modelling to provide design. Predictions were made of the likely extent of surfacecost effective solutions. water depletion resulting from the abstractions.
Water balance for Cornelly Group of QuarriesFreemans QuarryESI had assisted CEMEX UK Materials Ltd over a number of The planning permissions for the Cornelly Group of Quarriesyears in preparing annual reviews of the hydrological were subject to review under the provisions of themonitoring data for Freemans Quarry. In 2009 CEMEX Environment Act 1995(ROMP). The National Assembly forinstructed ESI to prepare a hydrogeological impact Wales (NAW) had concerns about the potential impacts ofassessment to support the planned increased depth of further working of the quarries.working, and subsequent restoration of Freemans Quarry.The report concluded that only occasional, limited dewatering The NAW requested Environmental Statements to assist in thewould be required to work the next bench and that any minor determination of the ROMP submissions. Tarmac appointedimpacts from working the final bench could be mitigated by ESI to carry out a hydrogeological investigation and impactdischarge of the water to local soakaways. assessments, the work involved field investigations (construction of 20 new monitoring boreholes and boreholeIn reviewing the report, the Environment Agency offered to and surface geophysics), monitoring (level, flow and quality),provide outputs from its regional water resources study to allow tracer tests, data reviewand analysis, development of aa more quantitative approach to be adopted. ESI therefore conceptual model and preparation of the Environmentalused the outputs from the Agency’s 4R recharge-runoff model Statement. Negotiation and technical discussion with theto develop transient water balances for the local area in order regulators was a central part of the assessment due to theto quantify the quarry dewatering more accurately. This work complexity of the local hydrogeology and the potential degreesupported the findings of the original investigation. of uncertainty in any predictions that could be made.ESI Ltd.160 Abbey ForegateShrewsburyShropshireSY2 6FDT: +44 (0) 1743 276100E: email@example.comW: esinternational.com