1.2 Contact details of resource persons and institutions involved in the assessment and documentation of the Technology

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

University of Stellenbosch (University of Stellenbosch) - South Africa

1.3 Conditions regarding the use of data documented through WOCAT

When were the data compiled (in the field)?

06/12/2001

The compiler and key resource person(s) accept the conditions regarding the use of data documented through WOCAT:

Yes

2.1 Short description of the Technology

Definition of the Technology:

Rehabilitation of areas degraded by strip mining, through returning stockpiled topsoil and transplanting of indigenous species, to promote revegetation.

2.2 Detailed description of the Technology

Description:

In contrast to the land degradation commonly caused when ‘strip mining’ is carried out, a land rehabilitation technology, which was first developed experimentally, is now routinely applied by mining companies on the west coast of South Africa. Indeed it is now a legal requirement in South Africa for mining companies to rehabilitate mined areas to a condition and productivity equivalent to the pre-mining situation.
The primary purpose of the technology described here is to achieve this result – thus allowing the site to be used again for extensive grazing by sheep and wild animals. Revegetation also reduces wind erosion. The technology further contributes to increasing biodiversity, as particular attention is given to planting a range of locally endemic and other indigenous species.
The sequence of operations is as follows: during strip mining operations the topsoil is pushed to one side by bulldozer, and stockpiled. The substrata is then excavated mechanically, removed by tipper truck, and processed to extract the heavy metals. The tailings (waste materials) are returned by tipper truck to the area from which they were mined, and then levelled by bulldozer. The stockpiled topsoil is returned and spread by bulldozer over the levelled tailings. Indigenous succulents and other plant species are dug out by hand, with a spade, from either the surrounding areas of natural vegetation, or from the piles of topsoil (where plants may have naturally established) and transplanted manually into the newly spread topsoil. The planted areas are protected from wind erosion by erecting fine mesh nylon netting as windbreaks. These are 0.8 metre high and 5 metres apart. The nets are usually installed for a period of up to 2-3 years. Subsequently they are removed, once the vegetation has successfully become re-established, and they may be re-used at the next rehabilitation site. Maintenance activities continue for a few years – until the site is rehabilitated. An individual mine strip is usually about 1 km long and some 100 m wide.
This form of strip mine rehabilitation has been in operation since 1990, and costs on average just over US$ 200 per hectare, with all expenses met by the mining company. This particular approach was developed for the Anglo-American subsidiary – ‘Namaqua Sands’. A similar approach was adopted by ‘PBGypsum Mines’ located further inland, where rehabilitation is also conducted on several hundreds hectares of mined land. Not all mining companies use the same technology, however.

Purpose of the Technology: Establishment activities:
Mining activities (not part of technology)
1.Removal and stock piling of topsoil
2.Excavation, removal and processing of substrata to extract heavy minerals
3.Return and levelling of the mine tailings
4.Return and spreading of topsoil Technology activities
5.Collection/digging up of indigenous plants
6.Transplanting into returned topsoil
7.Erection of fine mesh nylon net windbreaks Activities 1-4 are a continuous process associated with the speed of mining activities and involve the use of heavy earth moving machinery (bulldozers, front end loaders, tipper trucks). Activities 5&6 take place immediately prior to the onset of the rainy season and involve hand labour for collection and transplanting and tractor and trailer for transporting collected plants. Activity 7 can take place at any time of the year involving hand labour for erection of the nets and tractor and trailer for transport.

Maintenance / recurrent activities per year:
Maintenance activities restricted to:
1.Ensuring the nylon nets remain upright
2.Supplementary watering during the winter months, when rainfall inadequate, to support plant growth

2.3 Photos of the Technology

2.5 Country/ region/ locations where the Technology has been applied and which are covered by this assessment

2.6 Date of implementation

If precise year is not known, indicate approximate date:

• less than 10 years ago (recently)

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• during experiments/ research

Comments (type of project, etc.):

Developed at University of Stellenbosch

3.2 Current land use type(s) where the Technology is applied

Comments:

Major land use problems (compiler’s opinion): Overgrazing

Major land use problems (land users’ perception): Aridness and climate change. Erratic rainfall/climate. Frequent drought.

Ranching: Yes

Constraints of mines and extractive industries: Stockpiling of topsoil; processing of subsoil

3.3 Further information about land use

Water supply for the land on which the Technology is applied:

• rainfed

Number of growing seasons per year:

• 1

Specify:

Longest growing period in days: 120Longest growing period from month to month: Jun - Aug

3.5 Spread of the Technology

Specify the spread of the Technology:

• evenly spread over an area

If the Technology is evenly spread over an area, indicate approximate area covered:

• 1-10 km2

3.6 SLM measures comprising the Technology

Comments:

Specification of other vegetative measures: translocation of indigenous plants

Specification of other structural measures: land levelling, artificial windbreaks

Type of agronomic measures: zero tillage / no-till

Type of vegetative measures: scattered / dispersed

3.7 Main types of land degradation addressed by the Technology

Comments:

Main causes of degradation: industrial activities and mining

Secondary causes of degradation: over-exploitation of vegetation for domestic use, overgrazing

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:

• restore/ rehabilitate severely degraded land

4.1 Technical drawing of the Technology

4.2 Technical specifications/ explanations of technical drawing

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: moderate

Main technical functions: reduction in wind speed

Secondary technical functions: improvement of ground cover, increase in organic matter, increase of infiltration, increase in soil fertility

Scattered / dispersed
Vegetative material: O : other
Number of plants per (ha): 2000
Vertical interval within rows / strips / blocks (m): 5

Other species: Succulent plants

Slope (which determines the spacing indicated above): 4.00%

Structural measure: silt fence
Spacing between structures (m): 5
Height of bunds/banks/others (m): 0.8

Construction material (other): nylon net - small grid size

Silt fence: all 5m and height of 0.8m

4.3 General information regarding the calculation of inputs and costs

other/ national currency (specify):

Rand

Indicate exchange rate from USD to local currency (if relevant): 1 USD =:

9.07

4.4 Establishment activities

	Activity	Type of measure	Timing
1.	Collection of plants from natural vegetation	Vegetative	Pre-rainy season
2.	Collection of plants from topsoil stockpiles	Vegetative	Pre-rainy season
3.	Transport plants to rehabilitation area	Vegetative	Pre-rainy season
4.	Plant all plants	Vegetative	Pre-rainy season
5.	Insert droppers into net pockets	Structural	all year
6.	Spread nets over topsoil areas	Structural	all year
7.	Erect nets and hammer in droppers	Structural	all year

4.5 Costs and inputs needed for establishment

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% of costs borne by land users
Labour	Labour	hectare	1.0	75.0	75.0	100.0
Equipment	Machine use	machine hours	0.5	134.0	67.0	100.0
Plant material	Seedlings	ha	1.0			100.0
Construction material	Nylon net	ha	1.0	70.0	70.0	100.0
Total costs for establishment of the Technology					212.0

4.6 Maintenance/ recurrent activities

	Activity	Type of measure	Timing/ frequency
1.	Topsoil pushed into stockpile	Agronomic	all seasons / continuous
2.	Subsoil removed and processed	Agronomic	all seasons / continuous
3.	Processed subsoil returned to mined area and levelled	Agronomic	all seasons / continuous
4.	Stockpiled topsoil spread over processed subsoil	Agronomic	all seasons / continuous
5.	Plants transplanted onto spread topsoil	Agronomic	just before rainy season / late autumn/winter
6.	Ensure nets remain upright	Structural	all year/continuous

4.7 Costs and inputs needed for maintenance/ recurrent activities (per year)

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% of costs borne by land users
Labour	Labour	ha	1.0	37.0	37.0
Total costs for maintenance of the Technology					37.0

Comments:

Per hectare

4.8 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

Labour costs

5.1 Climate

5.2 Topography

5.3 Soils

If available, attach full soil description or specify the available information, e.g. soil type, soil PH/ acidity, Cation Exchange Capacity, nitrogen, salinity etc.

soil fertility: very low, soil drainage / infiltration = low, soil water storage capacity = low

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Population density: < 10 persons/km2

Annual population growth: < 0.5%

80% of the land users are average wealthy.
20% of the land users are poor.

Off-farm income specification: Most of income from mining

5.7 Average area of land owned or leased by land users applying the Technology

5.8 Land ownership, land use rights, and water use rights

Land ownership:

• state
• individual, titled

Land use rights:

• leased

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Socio-cultural impacts

Ecological impacts

Soil

Biodiversity: vegetation, animals

Climate and disaster risk reduction

6.2 Off-site impacts the Technology has shown

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Low establishment costs and very low maintenance costs How can they be sustained / enhanced? Make use of whatever resources and potentials are naturally available (such as micro-catchments to trap rainwater and improve soil moisture conditions for plants) to lower establishment costs.
Costs are met by the mining company – no costs are transferred to those who subsequently use the land for grazing How can they be sustained / enhanced? Regular monitoring of soil and vegetation conditions.
Land productivity is restored and biodiversity increased How can they be sustained / enhanced? Seeding as well as transplanting.
Wind erosion minimized.

6.8 Weaknesses/ disadvantages/ risks of the Technology and ways of overcoming them

Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view	How can they be overcome?
Rehabilitation is an extra cost for the mining company.	Ensure mining company meets the costs through enforcing legislation.