PULLES HOWARD & DE LANGE INC.

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MINE WATER MANAGEMENT AND TREATMENT

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Evaluation and audit of mine water management and treatment practices at South African gold and coal mines

An assessment and audit of the mine water management and treatment practices employed on surface and underground, in the mines, metallurgical plants, potable and sewage systems, rivers, streams and dams has been carried out at over 30 South African gold and coal mines.

A Manual On Mine Water Treatment & Management Practices in South Africa

Based on two years of extensive research, a detailed manual which defines mine water treatment and management practices in South Africa has been issued. This manual defines the available technical options, the current state of mine water management and treatment in South Africa and internationally, current research and knowledge gaps and research needs. This manual is being used as the standard textbook for mine water management in South Africa.

Passive systems for the treatment of mine effluents

An overseas study tour was undertaken to evaluate the state of the art with regard to biological passive treatment systems for use on mine effluents. Passive systems which were evaluated include anoxic limestone drains (ALD), successive alkalinity producing systems (SAPS), oxidation ponds, anaerobic wetlands, aerobic wetlands, anaerobic sulphate reducing beds, algal rock filters and biogenic sulphide reactors. Pulles Howard & de Lange is currently managing a large research project which is aimed at developing design, construction, operation and maintenance guidelines for passive treatment systems for mine effluents. This research is being undertaken at Arnot Colliery and Western Areas Gold Mine. Feasibility studies on the use of passive systems for Natal Anthracite colliery were undertaken and pilot plant studies are being undertaken at Vryheid Coronation Colliery.

Development of passive treatment systems for Vryheid Coronation Colliery

Contaminated decant from water adits into old underground workings at Vryheid Coronation Colliery is being evaluated with a view to designing and building passive water treatment systems. Problem contaminants include acidity, sulphate and certain heavy metals. A pilot plant, incorporating various novel elements, has been designed, constructed, commissioned and evaluated for over a year. Information gathered will provide the detailed design criteria for full scale systems.

Development of detailed water management, treatment and monitoring strategies for mines

Detailed impact assessments have been undertaken and appropriate water management, treatment and monitoring strategies were developed for numerous gold and coal mines in Southern Africa. These strategies cover both underground and surface operations.

Generic water balance for the South African coal mining industry

Data has been collected for most coal mines in South Africa (representing more than 75 % of South Africa’s coal production) and a series of generic water balances have been developed to cover the various types of mining and the different water circuits. The water balance can be used by the mining industry, catchment authorities and parties affected by coal mining water use and discharge.

Determination of the suitability of alternative carbon sources for sulphate reduction in the passive treatment of minewaters.

The overall aim of the project is to identify suitable low cost carbon sources for sulphate reduction in the passive treatment of mine waters. This project provides information which integrates into the other passive treatment development work being undertaken by PHD.

Pollution contained in the unsaturated and saturated zones beneath reclaimed mine dumps - a preliminary assessment

The primary aim of this project is to identify the nature and extent of contamination in the unsaturated and saturated zones beneath reclaimed slimes dams and sand dumps and to define the need to develop appropriate remediation measures.

Wismut, Germany, Passive treatment systems

PHD is providing input into a project to define suitable technology for the long-term treatment of contaminated effluents from the former Wismut uranium mining sites in Germany. This project is being undertaken for Brenk Systemplanung on behalf of the German environmental regulating authorities. PHD’s focus on this project is the identification of suitable pasive treatment technologies for the removal of acidity, heavy metals, radionuclides and sulphates.

Setting up ISO : 14 000 for Iscor Mining Environmental Management Services

PHD, in association with Margeret Rawicz and Associates are currently in the process of developing an Environmental Management System for Iscor Mining Environmental Management Services based on ISO : 14 000.

Design / evaluation of lime dosing, soda ash dosing and flocculation systems for mines

Various underground and surface mine water neutralisation systems have been evaluated and/or designed for numerous gold and coal mines in South Africa and Zimbabwe.

Design / evaluation of disinfection systems for mines

Various underground and surface mine water disinfection systems have been evaluated and/or designed, for different gold and coal mines.

Design and costing of sand and multi-media filtration systems for mine effluents

Various detailed and/or conceptual designs, plant layouts and costings were prepared for sand and multi-media filtration systems at various gold and coal mines.

Evaluation of tubular reverse osmosis (RO), electrodialysis reversal (EDR) and SPARRO desalination technology for mine water treatment

Research and development work was undertaken at various mines to evaluate the various desalination technologies which are available, in terms of their suitability for treating mine water. Evaluations were undertaken on highly saline but non-scaling mine waters as well as the scaling calcium sulphate type waters most typically found in the coal and gold mining industry. Various reports and papers have been prepared which define the application potential of the different technologies, pros and cons of each and relative capital and operating costs.

Design, costing, construction, commissioning and evaluation of settling systems for mine waters

Extensive research and development work was undertaken at various mines on settling systems for the removal of suspended solids from water. These studies focused on the development of ultra-high rate systems and numerous reports and papers have been published. This technology has also been patented.

Information transfer, extraction and management system for mine water management and treatment.

The primary aim of this project, which is funded by the Water Research Commission, is to develop a computerised Information Transfer, Extraction & Management System (ITEMS) which enables users to gain access to local and international information on mine water quality, management, treatment and research.

Development of water and salt balances for Target Gold Mine

Water and salt balances were developed for the various Lorainne Gold Mine shaft systems and the new Target mine. These balances were developed on the basis of underground visits and an understanding of the underground water reticulation system


Preparation of a detailed mass water balance for a proposed new Colliery

A detailed mass water balance was prepared for a proposed new Colliery to be developed in the Eastern Transvaal. The study included detailed geohydrological and surface hydrology studies and modelling in order to predict water entering the mine and the surrounding streams. The water requirements for the mine were developed and specified and alternative water supply sources were evaluated. Discussions were held with Eskom and the Department of Water Affairs to evaluate the technical and economic feasibility of obtaining water from various water transfer pipelines, rivers and dams.

Investigation and costing of solid and liquid waste disposal facilities and systems for a proposed new Colliery.

A detailed investigation, design and costing of alternative systems for the disposal of discard, slurry, mine effluent and sewage was undertaken for a proposed new Colliery in the Eastern Transvaal. Detailed construction plans, capital and operating costs were prepared.

Screening evaluation of water management / treatment options for New Vaal Colliery

Various water management or treatment options of underground water at New Vaal Colliery were examined in terms of technical and economic feasibility.

Reclamation of effluents at Matla Colliery with modelling of reclaimed water quality, conceptual design and costing of required water treatment plant

Water and salt balances were developed for the existing water circuits (mine service, sewage and effluent). A number of potential water reclamation strategies were developed to reduce potable water input and to eliminate all effluent discharges. The existing and proposed water circuits were dynamically modelled such that circuit water qualities could be predicted. Fitness-for-use criteria were developed for the main water users and an appropriate water treatment plant, incorporating pH control, disinfection, filtration and sludge disposal was designed and costed. Cost and strategic benefit assessments were undertaken.


Development and conceptual design of neutralisation systems for Natal Anthracite Colliery

On the basis of site visits and various laboratory investigations, a low-maintenance passive neutralisation system was specified for treating the water from NAC's No 2 water adit. Various options were evaluated for their potential suitability, including anoxic limestone drains, anaerobic wetlands, fluidised limestone reactors and the addition of powdered limestone or lime. An appropriate lime dosing system was developed and conceptually designed. Capital and operating costs were defined.

Characterisation of effluent systems and identification, assessment and costing of water management and treatment options for Zincor mineral processing plant

A detailed effluent flow and quality monitoring programme was developed and implemented. The data was evaluated and modelled and the resultant quality of various effluent blends was determined. The major water users were identified, fitness-for-use requirements were defined and appropriate treated effluent/ potable water blends were simulated. Performance specifications were set for an appropriate effluent treatment plant and various effluent treatment options were evaluated. Conceptual designs and capital and operating costs were developed for various effluent treatment and brine disposal options, including softening followed by reverse osmosis, SPARRO, GYPCIX ion exchange, and mechanical evaporation systems.

Assessment and remediation of evaporation facilities for seepage from a discard dump

An existing evaporation facility at an Eastern Transvaal colliery was evaluated and remedial measures were specified to deal with existing leaks in the facility. The studies also included recommendations on resizing and redesigning the evaporation facilities to better deal with the effluent volumes generated on site.


Evaluation of electrodialysis reversal and reverse osmosis water treatment options for Kleinkopje Colliery
A project was undertaken to advise Kleinkopje on the technical and economic aspects relating to full-scale Reverse Osmosis and Electrodialysis Reversal treatment options for the mine. Detailed review of plant designs and cost estimates were undertaken, disposal of brines and sludges were evaluated in terms of toxicity, design and cost implications. Recommendations were made on the appropriate technology to be implemented.

Preparation of a conceptual specification and costing of potable, sewage and process water reticulation systems for a new coal mine.
All the different water reticulation systems for a proposed new mine were conceptually designed, specified and costed. The design included all pipelines, pumpstations, tanks, etc.

Development of water and salt balances for Durban Navigation Collieries
Detailed monthly water and salt balances were prepared for Durnacol over the period of more than a year as the basis for identifying water management problem areas and to define appropriate management strategies.