Archaeological impact assessments (AIAs) are often commissioned as part of the heritage component of an Environmental Impact Assessment (EIA) and are required under Section 38(1) of the National Heritage Resources Act NHRA of 1999 (Act 25 of 1999), Section 38(8) of the National Environmental Management Act (NEMA) and the Mineral and Petroleum Resources Development Act (MPRDA).
The process of archaeological assessment usually takes the form of:
- A scoping or initial pre-assessment phase where the archaeologist and developer’s representative establish the scope of the project and terms of reference for the project.
- Phase 1 archaeological impact assessment.
- A Phase 2 archaeological mitigation.
- A Phase 3 heritage site management plan.
2 Phase 1 archaeological impact assessment
Phase 1 archaeological assessments generally involve the identification and assessment of sites during a field survey of a portion of land that is going to be affected by a potentially destructive or landscape-altering activity.
The location of the sites is recorded and the sites are described and characterised. The archaeologist assesses the significance of the sites and the potential impact of the development on the sites, and makes recommendations.
It is essential that the report supply the heritage authority with sufficient information about the sites to assess, with confidence, whether or not it has any objection to a development, indicate the conditions upon which such development might proceed and assess which sites require permits for destruction, which sites require mitigation and what measures should be put in place to protect sites that should be conserved.
Minimum standards for reports, site documentation and descriptions are clearly set out by the South African Heritage Resources Agency (SAHRA) and supported by ASAPA.
The sustainable conservation of archaeological material (in situ) is always the best option for any sites that are deemed to be of importance. The report needs to indicate which sites these are, explain why they are significant and recommend management measures.
In certain kinds of developments which involve massive intervention (mining, dam construction etc), it is not possible to reach a conservation solution other than to develop a programme of mitigation which is likely to involve the total or partial “rescue” of archaeological material and its indefinite storage in a place of safety.
Archaeological mitigation or Phase 2
If a Phase 1 report finds that certain archaeological sites in a development area are of low significance, it is possible to seek permission form the heritage authority for their destruction. The final decision about this is taken by the heritage resources authority, which should give a permit or a formal letter of permission, or in the case of an EIA (in South Africa) issue a comment supporting destruction.
Phase 2 archaeological projects are primarily based on salvage or mitigation excavations preceding development that will destroy or impact on a site. This may involve collecting of artefacts from the surface, excavation of representative samples of the artefactual material to allow characterisation of the site and the collection of suitable materials for dating the sites. The purpose is to obtain a general idea of the age, significance and meaning of the site that is to be lost and to store a sample that can be consulted at a later date for research purposes. Phase 2 excavations should be done under a permit issued by SAHRA, or other appropriate heritage agency, to the appointed archaeologist. Permit conditions are prescribed by SAHRA, or other appropriate heritage agencies, and include as minimum requirements reporting back strategies to SAHRA, or other appropriate heritage agencies, and deposition of excavated material at an accredited repository.
Should further material be discovered during the course of development, this must be reported to the archaeologist or to the heritage resources authority and it may be necessary to give the archaeologist time to rescue and document the findings. In situations where the area is considered archaeologically sensitive the developer will be asked to have an archaeologist monitor earth-moving.
Phase 3: Management plan for conservation and planning, site museums and displays
On occasion, the Phase 2 may require a Phase 3 programme involving the modification of the site or the incorporation of the site into the development itself as a site museum, a special conservation area or a display. Alternatively it is often possible to re-locate or plan the development in such a way as to conserve the archaeological site or any other special heritage significance the place may have. For example in a wilderness area or open space when sites are of public interest the development of interpretative material is recommended and adds value to the development.
Permission for the development to proceed can be given only once the heritage resources authority is satisfied that measures are in place to ensure that the archaeological sites will not be damaged by the impact of the development or that they have been adequately recorded and sampled. Careful planning can minimise the impact of archaeological surveys on development projects by selecting options that cause the least amount of inconvenience and delay.
The process as explained above allows the rescue and preservation of information relating to our past heritage for future generations. It balances the requirements of developers and the conservation and protection of our cultural heritage as required of SAHRA and the provincial heritage resources authorities.