Small scale mining activities which involve surface mining is an acceptable means of mineral exploitation in Ghana but has serious environmental consequences. Although a number of laws and research papers have been written on restoration after a piece of land has been mined, not much detail is provided on the actual processes involved. This review paper attempts a look at the process of restoration with projections on cost of restoration. Although it is based on activities at a predominantly farming community like Akyem Hemang in the Fanteakwa district of the Eastern region of Ghana, the principles involved will be applicable to other mining communities in the tropics. The paper looks at aspects of surface mining popular in rural areas of Ghana and attempt to explain the process of restoration with suggestions on how to measure success and how to involve affected communities to safe guard and ensure the success of the programme. A licensed concession can be as small as 3acres or as large as 25acres and can be mined for 3-5 years after which the land should be reclaimed to a productive state. The reclamation process, after field establishment should last for at least 5years to determine success. Small scale mining is defined as the use of rudimentary implements as well as the more sophisticated mining operating at a relatively low level of production with limited capital investment. It is carried out in rural farming communities and is popular with itinerant poorly educated people and usually results in severe deterioration to the environment, especially, crop land; posing serious health risks to communities in which it is carried out. The deterioration results from the destruction of vegetal cover and excavation of the overburden to assess the mineral bearing soil. Where farm lands or forested lands have been affected, a combination of natural and artificial reclamation is recommended. The process of reclamation should be planned and begins when topsoil at the mined site is removed to store separately from the subsoil and over-burden at the pre-mining stage. Topsoil however cannot be stored for too long as the quality deteriorates with time. Depending on the depth of excavation, restoration should involve importation and replacement of subsoil to a depth of 600mm -900mm spread in 150mm layers, and left to settle naturally for a period of 3 -6months. When the land is sufficiently settled, topsoil mixed with manure should be laid over the subsoil to a depth of 150mm minimum after settling. This is followed by sowing of nitrogen fixing leguminous green manure by broadcasting to provide the first blanket of vegetative cover to protect the soil from the direct effect of the elements. Although Crotalaria juncea (Sunnhemp) is highly recommended nitrogen fixing leguminous annual with high biomass production for highly degraded land, other area-specific nitrogen fixing plants can be recommended by the area agricultural extension officer. About 60days after sowing of the green manure cover crop, when it is in blo...

Perennial flooding has become a major feature in urban areas in developing economies generating research interest towards finding alternative approaches to stormwater management which could complement the existing systems and help address the challenge of flooding. One of such alternative approaches is nature-based stormwater management and flood control, the implementation of which could be affected by soil erosion. This paper, as part of a wider research, was developed to determine the extent of the threat of soil erosion to stormwater management in an urban area on the example of Greater Accra Metropolitan Area, Accra Ghana as the focus of the research. Landsat 8 images (2014) were used in the research to prepare the Landcover maps. Daily rainfall data from 6 raingauge stations from 1972 to 2014 were utilized to prepare the rainfall erosivity factor maps, whereas DEM was used to prepare the slope and slope length (SL) factor maps. The land cover map with an overall accuracy of 73.6 and Kappa 0.7122 was combined with literature sources to prepare the vegetative cover factor map, and conservation practice factor map. A soil series map, prepared and updated with literature sources and data from the Harmonized World Soil Database on physical parameters, was used to calculate the soil erodibility factor (K factor) for each soil series. These were integrated into RUSLE model as 30 m raster maps to generate a soil loss map at tons/ha/yr. The results produced rainfall erosivity index values based on the modified Fournier index ranging between 0.058 and 23.197 which is classified as low. Low soil erodibility factor (K) ranging between 2.9×10 -5 and 8.5×10 -2 t ha/MJ mm indicated low susceptibility to erosion, SL factor value showing areas of low to almost flat relief with a few isolated areas of moderate slope length were generated. A soil loss of 69,5918 tons/ha/yr classified the soils as having high potential soil loss. The results showed a very low soil loss threat of 0-5.1853 tons/Ha/yr for more than 90% of the study area. Targeted intervention for source areas with high potential soil loss will contain any threat of erosion and sediment yield to the implementation of an infiltration-based stormwater management and flood control system.

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