Analysis of Abandoned Mine Wastes Disposal Techniques in Malawi: A Concept of Circular Economy

Non-operational mines mostly constitute of significant quantities of valuable mineral resources within tailings and waste rock that can be disposed properly using innovative techniques. Proper waste disposal techniques do not only reduce the need for new mines to be developed but also have broad beneficial results on mining environmental impact. This paper presents a solution on abandoned mine wastes in Malawi. Malawi government wants to embrace techniques on former mine waste recycling operations that incentivize investment. Thus, this analysis proposes abandoned mine waste recycling technique for Malawi government to adopt. Recycling technique, as one of the current direction methods, is determined for adoption. The powerful impacts of recycling principles in turning Malawi’s abandoned mine wastes into beneficial products that can support and sustain its economy are given. The concept of circular economy is prominently in the picture, so the wastes can be changed into wealth and other created benefits.


Introduction
The idea of circular economy is acquiring popularity globally among different stakeholders such as governments, industries, and consumers. Initially, the concept focused on manufactured products such as goods and services. Abandoned mine wastes were not conspicuously in the picture (Knapp, 2016;Lèbre., 2017). This can be because abandoned mine wastes seem like the antithesis of circular economy (Ellen, 2014;Soderqvist et al., 2015;Thimmiah, 2014). Over the last few years, mining wastes from abandoned mines have quickly caught up. Major consultancies have published articles that shape abandoned mine wastes circular economy transition as not a threat but rather an opportunity (ICMM, 2018). However, the concept of circular economy on abandoned mine wastes is yet to gain momentum in Malawi. If Malawi government can start applying the circular economy concept principles on its abandoned mine wastes, then more revenue will be generated that can sustain its economy (Daniel et al., 2019;Hubert, 2016;Zhenling et al., 2010).
Malawi is one of the south-eastern African countries. It is rich with natural resources such as deposits of coal, uranium, cement, bauxite, gold, nickel, niobium, graphite, precious stones, rare earths, gemstones, gas, and oil (Carter et al., 1973;Lombe, 2003). Many coal sites and small uranium areas are in northern part of the country (Rumphi and Karonga districts). Gemstones and rare earths deposits are in the southern region (Phalombe district). Gas and oil deposits are around Lake Malawi. Gold minerals are in central region (Lilongwe district-Nathenje, and Nkhotakota district), and eastern region (Mangochi district-Makanjira) (Ezekwesili et al., 2009).
Over tens of years, mining of resources from these areas has left many mine sites abandoned (Ezekwesili et al., 2009). Associated wastes from these abandoned mine sites have resulted in extensive damage to the environment: They have destroyed more land by making them impossible for re-use purposes; affecting the microbial communities, destroying the vegetation, and hindering the humans (EITI, 2019; Grynberg et al., 2021). Some of the major abandoned mines in Malawi include the Nkhachira coal mine, Kayerekera uranium mine, Kaziwiziwi coal mine, Mchenga coal mine, Eland coal mine, Kautsi hill quarry mine, Strabag quarry mine, and Zunguziwa quarry mine (Mines and Minerals Act, 2019;Thokozani, 2018). The associated mine wastes from these Malawi abandoned mines have not been disposed (Thokozani, 2018).
Hence, the main necessity of this analysis is to propose a disposal technique using the circular economy concept that include a recycling-focused approach as a clean-up strategy of Malawi's abandoned mine wastes. The analysis focuses on Malawi government to: 1) Know that wastes from abandoned mine sites comprise minerals due to uneconomic or inefficient extraction methods during initial processing, and that proper disposal techniques together with policy incentives make them economical. 2) Consider abandoned mine wastes as immeasurably recyclable, and that recycling is significantly cost effective as compared to new metal mining. This implies that, reprocessing abandoned mine waste straddles between the line of mining and recycling. 3) Develop an enhanced capability that track abandoned mine waste minerals from their source to enable for new business models potentiality.
Thus, Malawi government should aim at acting more like a commodity company. It can sell abandoned mine wastes from own recycling facilities or right away from mines, that's the wastes can be changed into wealth and other created benefits in an integrated business model approach.

Status
High demand for minerals in Malawi has left a lot of mining areas abandoned and associated wastes nondisposed (Ezekwesili et al., 2009;Human Rights Watch, 2016; International Union for Conservation of Nature, 2012; Kabir et al., 2015). Abandoned mines have created wastes that have caused great losses of both aquatic and terrestrial habitation (Human Rights Watch, 2016). Still Malawi government is yet to determine techniques on abandoned mine wastes that give more value to economic benefits and to environment protection (Kabir et al., 2015). Recently, Phiri et al., (2010) observed the lack of detailed information and policies by Malawi government on how abandoned mine wastes can be effectively disposed into valuable benefits despite their inclusion in the decommissioning activities of mine closure. Maneya et al., (2014) supported Phiri et al., (2010) observation and reported that the need to reclaim abandoned mine waste mineral commodities with emerging techniques for economic generation purposes are not properly managed or given much attention in Malawi.
The abandoned mine waste management is part of Environmental and Social Impact Assessment (ESIA) in Malawi (Government of the Republic of Malawi, 2002;Kapyepye, 2012;Land Use Consultants, 2014). ESIA mining jurisdiction requires companies of mining to restore mine site to a condition that approaches the original state (Government of the Republic of Malawi, 2010). ESIA does not specifically address the issue of abandoned mine waste proper disposal methods after the mine closure. Recently, ESIA abandoned mine site restoration stipulation has focused on ecosystems -restoration of interconnected relationship between fauna and flora that was present before mining operation. This implies that the topsoil taken out is kept and then replaced at mine closure. Tree species and native plants are seeded. Native animals are re-introduced (Malawi Government Ministry of Finance Economic Planning & Development, 2017). Nonetheless, it is not easy to restore ecosystem as it was, even though this sounds idealistic. In fact, ecosystem is a by-product of centuries of environmental changes. Soil fungi, bacteria, and other organisms in topsoil might not last storage years. Geological materials below the topsoil might have altered the hydrological conditions (Denholm et al., 2008;Emma et al., 2018;FRTR, 2007;USEPA, 2008). Thus, the difficulty in recreating ecosystems underscores the falsity of this belief in Malawi ESIA mining jurisdiction.

Eland Coal Mine
At abandoned Eland coal mine in Mwaulambo, Karonga district, there are more coal gauge and coal sludge mineral wastes (Chimwala, 2016). The Eland coal mine was closed in 2015 (Thokozani, 2018). The surrounding communities have been complaining about the negative impacts associated with the abandoned mine wastes since its closure. They complain about being not informed of the mine closure plans, including measures by the responsible company or the Malawi government intended at mitigating risks stemming from the deserted mine site (Chimwala, 2016). The company left behind unprotected deep holes, several piles of coal, and open pits filled with contaminated waters that still threaten the lives of the surrounding communities (Human Rights Watch, 2016).

Kautsi Hill Quarry Site
Another case is the abandoned Kautsi hill quarry at Nathenje, Lilongwe district, which contains contaminated soils, waste rocks, and small dams of mine influenced waters (

Kaziwiziwi Coal Mine
Another example is Kaziwiziwi coal mine which was abandoned in 2012 (Maneya et al., 2014). Kaziwiziwi coal mine contains fly-ash wastes (Maneya et al., 2014). Public consultation was conducted to establish perception about abandoned mine fly-ash wastes in order to help the Malawi government to come up with propositions (Malawi Government Ministry of Finance Economic Planning & Development, 2017). The approaches employed were observations and key informant interviews (Maneya et al., 2014).. The determinations from the consultation of the public were summarized by government representatives. The summary mainly focused on campaigns of afforestation and reforestation (Maneya et al., 2014).. There was no explanation in the summary on how the abandoned fly-ash mine wastes and all contaminated wastes at the site are to be re-gained, and very little on environment related issues (Maneya et al., 2014).. Only negative impacts mentioned in the summary were the loss of informal business, loss of jobs, and loss of government revenue due to mine closure. The benefits that can be obtained from the abandoned waste fly-ash which might include job opportunities creation, integrated business models, revenue generation, and etc., were not mentioned in the report (Doley, 2013;Haibin, 2010;US GAO, 2011).

Challenges
The setup of planning in Malawi abandoned mine wastes relies upon ESIA process (Government of the Republic of Malawi, 1981;Land Use Consultants, 2014). This is alike to other countries where planning is performed as part of ESIA or as separate but still linked process. ESIA guidelines only explain basic statements on possible mitigation measures of abandoned mine wastes (Bergquist, 2013;Clewell et al., 2004;World Bank, 2004). The details on how the abandoned mine associated wastes are to be re-gained for other created benefits are not directly addressed (World Bank, 2004). Some specific challenges include: 1) Lack of detailed guidelines and codes of practices on techniques of disposing wastes from Malawi abandoned mines. Abandoned mine wastes have become a serious threat to humans and environment rather than an opportunity. This is a pressing problem to be figured out by Malawi government. 2) In ESIA, there is no implementation of time lined priorities and goals that ensure that the Malawi abandoned mine wastes are addressed first, and are clearly defined. This implies that abandoned mine wastes are not conspicuously in the first picture, and seem like the antithesis of circular economy. 3) Lack of an efficient, repeatable disposal technique and methodology that considers abandoned mine wastes as a possible business model to be pointed out and protected on the basis of multiple and corroborative efforts.

Status
The current direction in many mineral resource based countries world-wide (such as the Eastern Europe, Caucasus, and Central Asia (EECCA) region countries) is recycling, which is among the most circular economy principles direct applications in mining industry (Ellen 2014;European Commission, 2014;Thimmiah, 2014). Recycling involves reprocessing wastes from old mining operations. Former mine wastes are reprocessed to recover mineral resources (Ambec, 2013;Government of Western Australia, 2015). This action potentially creates jobs, increases environmental protection, and integrates abandoned mine wastes into commodity value chains (Bergquist, 2013;Knapp, 2016).

Kazakhstan -Kounrad Copper Mine
The Kounrad copper mine, near the city of Balkhash in Kazakhstan country, was abandoned in 2005 (OECD, 2017). The abandonment left behind substantial waste dumps comprising of recoverable copper [(OECD, 2017).
In the year 2007, the Central Asian Metals developed interest on the site abandoned mine wastes. By the year 2012, it already built a solvent extraction -electro winning (SX-EW) plant. The recycling exercise removes metals from waste dumps by employing in-situ leaching. It then uses electro winning and concentrating processes to produce copper cathode. The copper cathode is exported for business to Turkey and other countries (Central Asian Metals, 2018). Recycling of existing waste dumps at the abandoned mine has been profitable (Central Asian Metals, 2018). The abandoned mine waste recycling technique has resulted in a low environmental impact since the recycling activities commenced (OECD, 2017). In the year 2016, the recycling activities were further expanded to reprocess more abandoned copper wastes. The project was pursued based on market principles. The operations have demonstrated support for circular economy approach on the abandoned mine wastes in both Kazakhstan and neighboring countries (Central Asian Metals, 2018).

USA -Tar Creek Superfund Site
Tons of chat piles at abandoned Tar Creek tristate zinc and lead mine sites in Oklahoma, USA caused widespread environmental contamination (Reisman et al., 2008;USEPA, 2008). The Oklahoma state highway department assessed the potential for recycling the chat waste materials (USEPA, 2008). The former mine chat wastes went through a mechanical wash process that distinguished the fine chat (which contains high concentrations of lead, cadmium, and zinc) from coarse chat, making it suitable for re-use purposes (Heden, 2002). The recycled chat waste was applied in an environmentally safe way as aggregate capsulized in asphalt and other sanctioned materials for road construction works and other construction activities. The recycled chat wastes at the site reduced mine waste volume environmental impacts, and boosted the Oklahoma construction business industry economically (Denholm et al., 2008).

Australia -Mount Morgan Mine
The Mount Morgan mine which is located at Central Queensland in Australia was abandoned in 1982 (Carbine Resources, 2018). The abandonment resulted in extensive environmental damage associated with the abandoned wastes (Terzon, 2018). In the same year of abandonment, 1982, tailings recycling operation began. The reprocessing project minimized further environmental damage. After eight years, operations were increased (Lèbre, 2017). The government took over the mine. It empowered measures which included new earthworks to enhance environmental protection (Lèbre, 2017). In 2016, Carbine Resources Company joined the initiative, and completed a feasibility study which targeted on mine waste recycling process continuation at the Mount Morgan site. The study aimed at recycling copper tailings (in form of copper sulphate), pyrite (as iron pyrite concentrate), and gold bullion (Carbine Resources, 2018). The project has created more economic benefits including reducing unemployment levels, environmental protection, and generating government revenue than initially anticipated (Lèbre, 2017).

Recycling
The current development option is recycling. Recycling method is one of the current techniques commonly adopted in many resource based countries for abandoned mine wastes clean-up exercises (Haibin, 2010; US GAO, 2011). Recycling option takes abandoned mine wastes and re-work them into useful materials. Recycling technique ensures that the abandoned mine waste is not discarded or thrown away but changed into riches, and also plays a crucial role in the concept of circular economy and environmental protection (Kokko, 2015;Söderholm, 2014;Thimmiah, 2014).
Some of the examples of mine wastes which can be recycled into created benefits from the perception of abandoned mine wastes in Malawi are: • Coal gangue wastes at former Eland coal mine and Mchenga underground coal mine can be used for power generation. Coal gangue undesirable for power generation can be used for the purposes of forestation, coverage and landfill. Coal sludge from these abandoned mines can also be converted into electrical energy through burning it. These abandoned coal wastes can play a crucial role in transforming the Malawi's energy sector, and also hiking the country's economy simultaneously if recycled (Haibin, 2010). The atmospheric pollution and malicious substances associated with coal wastes can also be effectively prevented at the same time. Thus, dramatically creating wealth and enhancing environment protection (Daniel et al., 2019;Moffat et al., 2014). • Fly-ash from abandoned Kaziwiziwi underground coal mine wastes can be recycled. Colored bricks can be obtained out of the recycling process. The colored bricks can be sold, as it is useful for beautifying road surfaces, in building architecture, for landscaping, aluminium production, surface subsidence mitigation, and many uses (Zhenling et al., 2010). This can generate business investments and boost the Malawi's economy. • Abandoned Nkhachira underground coal mine contains wastes that include gases such as methane from coal bed which together with underground coal-berried pollutes the atmosphere (Emma et al., 2018). This coal-bed methane gases can be extracted, and re-used as a valuable natural resource in industrial productions. The coal bed methane can also be properly disposed by re-using it in world industries for civil engineering usages, production industry usages, car fuel usages, and generation of power usages (Emma et al., 2018;Yosoon, 2016). Thus, creating an economic system that can be used to support the needs of Malawians. • The Mine Influenced Water (MIW) and waste rock stockpiles at abandoned Kautsi hill quarry mine, Kayerekera uranium mine, Strabag rock aggregate quarry mine, and Zunguziwa rock aggregate quarry should not just let go, but controlled and recycled for other activities that can support the Malawi's economy. Such activities may include using the MIW for industrial production, for construction works, for consumption, for agricultural irrigation, as fire protection water, and etc. MIW from these sites can be treated. Water resources such as artificial lakes which might lead to tourist attraction and generate foreign revenue in the process can be established out of MIW after treatment (Paladin Energy, 2017). Similarly, the recovered MIW can be recycled and used for generation of electricity or externally traded out ( Barr Engineering, 1986;Oruonye et al., 2018).

Recommendation
Malawi ESIA should consider abandoned mine waste as an opportunity rather than a threat. Recycling abandoned mine waste not only generates economic benefits but also minimizes environmental risk factors which non-operational mine constitutes. ESIA jurisdictions should present confluence of policies that together regulate, support, and motivate adoption of recycling technique, make processes more efficient in generating revenue, and reduce abandoned mine waste environmental impacts. Specific recommendations are as follows: • Consider abandoned mine waste comprehensive utilization as one of best results from former mines.
Malawi government needs to adopt recycling techniques to win over its former mine wastes into wealth. This saves natural resources, enhances environmental protection, and realizes great economic and social profits. • Ensure promotion and encouragement of abandoned mine waste recycling techniques for the sustainable gain of the natural environment, local communities and nation as a whole. This can be achieved by the Malawi government coming up with code of practice for abandoned mine wastes reclamation, more detailed requirements, guidelines, and good policies. • Prioritize abandoned mine waste recycling as a country priority for accomplishing sustainable growth in an integrated business model. Recycling techniques should be adopted as a significant objective for ecological restoration of abandoned mines. • Implement clear, comprehensive, and consistently enforced regulation. The regulatory framework should go beyond the mine life. It should promote good environmental management, and provides details on how the mine wastes are going to be recycled into created benefits that can both boost the country's economy and enhance environmental protection at mine closure. • Draw on international co-ordination, agreements, conventions, and information on proper recycling techniques that establish standards and frameworks for reprocessing abandoned mine wastes. • Establish that mine operators can import environmentally sensitive and more efficient abandoned mine waste recycling equipment with an exception of import duty. Malawi government needs to remove barriers on importation of new technologies for abandoned mine waste recycling purposes. This should include tax structure which motivates new equipment purchases that recycles abandoned mine wastes and meets environmental standards. • Use the means of training, education, and work experience to build human capacity. Ensure that abandoned mine wastes and environmental concerns together with solutions and new recycling techniques are included in mining related engineering curriculum. This helps enable better performance through skills availability.

Conclusion
This paper has determined that recycling technique eliminates environmental risk factors from abandoned mines. It converts the mine wastes into wealth and other created benefits. Once the mining operations have stopped, the associated remaining mining waste materials must be recovered. The recovered waste must be recycled into useful materials that both protect environment and generate economic and social profits. Proper recycling techniques of wastes from Malawi abandoned mines should prioritize on the attraction of a zero-waste society, in which a market and demand for virgin resources should likely continue for the foreseeable future. The specific conclusions drawn are: • Recycling technique is proposed for adoption for Malawi abandoned mine waste clean-up exercise.
• Abandoned mine waste is an opportunity and not a threat. It is a valuable asset to Malawi government. Under this very situation, the recycling technique for Malawi abandoned mine wastes is particularly important. • The recycling technique must be endorsed by public policy together with consumer buy-in in order to support new business models that integrate Malawi abandoned mine wastes into a global economy.
Lastly, further studies should be conducted. They should be aimed at inventing the most active, feasible, lower cost, and easily useable abandoned mine waste disposal modern technologies, modelling software, and machines that are to turn abandoned mine wastes into beneficial products which can support and sustain Malawi's economy in the concept of circular economy.