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Environmental costs related to Limestome mining at the Dura Quary site in Queen Elizabeth National Park, Kawenge

Introduction
20141027_115433Hima Cement (U) Ltd, Uganda’s leading cement manufacturer is part of Bamburi Cement Ltd which is a member of the Lafarge group. Lafarge is a French based leading producer of building materials in the world. Hima Cement (U) Ltd has a vision “to be a World Class producer that provides construction solutions to our customers across East Africa with a commitment to sustainability “.

Cement is an essential building material which is used in almost every construction project worldwide. Hima Cement (U) Ltd provides cement to several large scale and smaller scale consumers throughout East Africa. Key raw materials used to produce cement include calcium carbonate, silica, alumina and iron ore. These are extracted from limestone rock, chalk, clayey schist or clay.

Hima Cement (U) Ltd currently produces approximately 1480 tonnes of clinker per day and operates 2 major quarries, the Hima Quarry and the Dura Quarry. The Musekura quarry, just adjacent the Hima Quarry, was recently acquired by Hima Cement (U) Ltd, with certificate of approval from NEMA dated 9th November 2010.

Hima Cement (U) Ltd holds the Mining Lease for Musekura ML 0706 measuring 54.092 Ha. According to the Musekura Mining plan, the limestone reserves at Musekura Quarry are estimated at 543,400 tonnes, and will be mined in 3.6 years, at a mining rate of 150,000 tonnes per year.

Hima Cement (U) Ltd also holds an exploration licence (No. 0987) for limestone and clay in an area of 4.3km2 within the Hima Town Council Administrative boundaries.

 

1.2 Location of Dura Quarry
The Dura quarry is located in Ngoma Village, Kanara Parish, Nyabani sub county, Kamwenge District around coordinates 0.19294, 30.30865 (WGS’84). It is located within the boundaries of Mining lease 0248 in Queen Elizabeth National Park. A permit was obtained from UWA for the Dura quarry activities and a prospecting license from the Ministry of Energy and Mineral Development. The Mining lease covers an area of 450 ha. The Dura quarry is subdivided into 3 quarry sites (A, B & C) (Fig. 2), with only quarry C being mined (Figure 1). A section of quarry B approximately 40 ha falls within a Ramsar site and has therefore not been planned for as quarrying area. Quarry C covers approximately 520,625m2 and is the only active quarry in Dura quarry area.

Hima map

Other main drainage features in the area fall within the catchment of Lake George and include the Dura River, which drains into the Nsonge River and eventually Nsonge swamp. Rwenkerebe River divides the deposits as it flows westwards into the Dura River.

1.3 Description of Dura Quarry Operations
Map2Current Operations at Dura Quarry are within Quarry C. Open cast quarrying is undertaken once a week; on Wednesday’s at the quarry by a crew of 28 personnel including a quarrying engineers, 5 supervisors, 2 drillers, 1 blasting personnel, 2 electrical foremen and 14 crush operators. 4 security personnel are employed on operations at Dura.

Quarry site offices with a worker’s camp are located within Ngoma about 9 km from Dura Quarry. The site offices also include a yard for repairing the Quarry machinery and sanitary facilities.

The quarry site is approximately 20 km from Kamwenge Town Centre to the North of the Dura River and just 18 km from Hima Town. The limestone from the quarry is currently transported by road, 18 km from Dura through Rwimi Town with associated social impacts associated with transportation.

KEY SOCIO ENVIRONMENTAL CONCERNS OF MINING LIMESTONE AT QUARRY C;
i) Habitat modification –creating deep ecological foot prints around the Quarry site part of the park
The large disturbances caused by mining have disrupted the environments around the quarry, adversely affecting the aquatic habitats (streams and rivers), terrestrial habitats (grasslands, forests), and riverine wetlands that many organisms rely on for survival. Ecosystems and the communities and species they support need to be able to interact and exchange genetic material with other ecosystems, communities and populations of species in order to remain viable. Also, species need to be able to shift their ranges in response to climate change, allowing their continual adaptation.

The limestone quarry has broken up the continuity of the forest with the grassland. This has already resulted into disappearance of species and loss of particular ecosystem-specific functions. For instance, next to the quarry is an abandoned nest of Chimpanzee probably due to habitat modification.

Limestone mining operations using open-pit mining techniques in Dura has also resulted in significant deforestation through forest clearing and the construction of the road to the quarry. The formally intact remote forest has been opened up to the miners and land speculators.

Mining at the quarry is done by excavators which extract limestone up to a depth of between 5 to 10 m with a plan of extending to 15 m in near future. The originally forested area has been transformed into a large expanse of degraded area with smoke from the excavators as evidenced in the photos below.

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xi) Widening and deepening quarry
The quarry is continuing to grow as mining continues. It’s planned that the quarry will continue to operate for the next 25 to 30 years. This means continued expansion of the quarry with more and more cumulative impacts.

At the quarry, is also a challenge of waste management. Oils and lubricants have no clear store and are just placed in an open environment. There is a possibility of contamination of the soil with oils and lubricants for the excavator with consequent significant impacts on the environment. (See Photos of oil containers, and other waste disposal sites).

more cumulating impacts.

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(ii) Waste management issues:
At the quarry, is also a challenge of waste management. Oils and lubricants have no clear store and are just placed in an open environment. There is a possibility of contamination of the soil with oils and lubricants for the excavator with consequent significant impacts on the environment. (See Photos of oil containers, and other waste disposal sites).

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(iii) Dust nuisance
In the process of large-scale earthwork, dust emissions are inevitably a problem. These dust particles originate from the following potential sources: ore crushing, transportation of crushed ore, loading bins, mine and motor vehicle traffic, use of the road and waste rock piles. Dust can contain toxic heavy metals such as arsenic, lead, and other. These toxic heavy metals, when incorporated with dust can contaminate the air. The roads used by the trucks transporting limestone from the quarry to Hima Cement factory have a lot of dust. Fugitive dust escapes from trucks traveling on road. This airborne dust can travel long distances from a mining site as well as off the road and affect the health of communities and homes along the road. In addition, because of the high traffic on these roads, the general public and school children are exposed to accidents.

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(iv) Discharge of dissolved limestone and associated waste water into Dura River
The water from the four pumps operating 24 hours a day at the quarry is discharged directly into River Rwenkerebe a tributary of Dura River without treatment or even passing through settlement ponds. This effluent finally ends up into Lake George. The drain water contains dissolved limestone. It is envisaged that the continued pumping of this waste water which contains dissolved limestone for the next 25 to 30 years out of the quarry operations will generate cumulatively large quantities of dissolved limestone that will consequently result into accumulated impact on the riverine vegetation, fish population and other aquatic life in Lake George and the wetland ecosystem. The water quality in the rivers will deteriorate overtime as a result increase in salinity levels in the rivers due to accumulation of contaminants from the quarry.

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It’s also important to note that during the rainy seasons, the deep quarry foot prints in the environment get flooded with saline water from the limestone mine. This water is occasionally pumped into the artificial drainage channel and eventually released into the Dura River and this negatively affects the aquatic life of the river and in the long run the aquatic life of Lake George.

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(v) Erosion and sedimentation
Erosion and sedimentation present another environmental issue for the mine site C. During mining, a lot of material is generated in significant quantities; large quantities of sediment are transported by water erosion. The sediment eventually drops out of solution and sedimentation occurs at some point downstream from the erosive source. Erosion and sedimentation depends on: the degree to which the surface has been disturbed, the prevalence of vegetative cover, the type of soil, the slope length, and the degree of the slope.
The outcomes of erosion and sedimentation affect surface water run of, life in River Rwenkerebe a tributary of Dura River; and eventually Lake George where it finally drains.

vi) Biodiversity conservation and scenic viewing challenges
The Uganda Wildlife Act CAP 2000 provides for sustainable management of wildlife conservation areas and the conservation of wildlife biodiversity proportionately with other forms of land use in order to support sustainable use of wildlife for the benefit of the people of Uganda. It also promotes rare, endangered and endemic species of wildlife, eco-friendly control of problem animals, and economic and social benefits from wildlife among others. In addition, it permits biodiversity conservation, recreation, scenic viewing, scientific research and other economic activities compliant with conservation. Degradation of such sites through quarrying inside the park impairs this legal provision.

The current large scale quarrying activity generates stress to the wild animals around Dura quarry consequently affecting their abundance and distribution. As the case of DURA C site, it’s clearly reported by the mining workers and quarry supervisors that the destroyed patches of the chain link around the quarry site (approximately 4 square km chain link) is a result of the stressed elephants and buffalos that normally invade the quarry area after observing foreign objects in their habitat.
The numbers of animals in these areas around the quarry site have greatly reduced since the survey in 2009. The animals that were originally in the area, especially the ungulates, could have been decimated by human presence through poaching and encroachment on their habitats.

The low presence of wildlife at the quarry is due to much human activities going on like limestone mining and transportation. In addition, the noise generated during excavation of limestone and also from the four operating water pumps could also scare away animals; and also the highly degraded habitats around the mines as a result of the mining activity cannot support the wild fauna.

vii) Noise pollution
Machine operations during mining at the quarry generate a lot of noise. In addition, the quarry management operates four pumps that operate 24 hours a day generating a lot of noise too beyond the permissible levels. This threatens the animal populations, causing migrations, disturbance to animal breeding, among other impacts.

viii) Stagnant water in quarry pits and exposure of workers to Tsetse fly and mosquito bites
Stagnant water in quarry pits act as breeding grounds for mosquitoes hence increasing incidence of malaria in the neighboring community. This is a key Public Health concern.

In addition, tsetse flies were recorded and the workers complain of bites by the vector despite the protective gear they wear. The waste water that is generated after the mineral has been extracted remains in the pits while some is led into the settlement ponds. Pools of waste have accumulated in the quarry as stagnant pools. These have become the breeding ground for water-borne diseases causing insects and organisms like mosquitoes to flourish.

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(ix) Restoration Plan for the main quarry sites.
From the report given by the quarry supervisor, tree planting seems to be the one planned. However, this might not be enough. Tree planting cannot cover the deep ditches left behind by the mining activity. In addition, reports at site indicate more mining might go on for 20 to 25 years up front. The question is “how much foot print will it have caused? if the foot prints created are to be filled with soil, where will it come from ? Who will do this? Is this plan documented?
Specific recommendations:

  •  Hima Cement should restrict the land take under quarrying activities in the park.
  • Co-existence of wildlife and mining must be emphasized and develop practical strategies to ensure that the primary objective of conserving the nation’s biological diversity is not compromised and or lost.
  •  Identification and periodic surveillance of land use and cover at the quarry site and in the vicinity of the mining activity should be done.
  • Regular multistakeholder monitoring must be undertaken prior to, throughout, and following mineral working, with options for mitigation if mineral working causes an unacceptable impact.
  • A discharge plan should be developed to address the associated impacts on the aquatic life in the lake and the wetland ecosystem.
  • Regular analysis of effluents from the quarry in the government laboratory to ensure compliance with National standards.
  • The management of Hima Cement should devise other mechanisms to ensure that the quality of drainage water shall be such as not to pollute the receiving water or ground water and such measures should be pursued to prevent increase in salinity levels in receiving waters, to prevent the accumulation of dangerous or toxic compounds in the subsoil, capable of contaminating underground waters.
  • Hima Cement should emphasize strict implementation of the waste management plan at the quarry otherwise the current efforts of settling the water at the water sampling point for settling of the dissolved Calcium Carbonate does not suffice.
  • Hima Cement Ltd should establish settlement ponds to handle waste water specifically from the water pumps before discharge into the rivers such as Rwenkerebe which is currently not being done.
  • On Erosion and sedimentation, Hima Cement should minimize vegetation clearance around the quarry. In fact, vegetation clearance and disturbance of both water, animal and bird life is a major reason why such large scale mining in prohibited in ecologically sensitive areas such as parks.
  • On Stagnant water in quarry pits, Hima Cement (U) Ltd should partner with NGOs and Local Government in provision of health services including malaria prevention initiatives.
  • On waste management and the water catchment, Hima Cement (U) Ltd should closely work with the Districts of Kamwenge and Kasese and commit funds to support management of the Lake and Lakeshores; Rivers and Riverbanks; and Wetlands ecosystems.
  • Proper waste management of oils and lubricants at the quarry need to be emphasized.
  • The mining company should have a comprehensive restoration plan that goes beyond mere tree planting.