Dolomite stability investigations are required for all land classified as dolomitic land. Dolomitic land is considered land underlain by dolomite or limestone residuum or bedrock typically at depths of no more than:
- 60 m in areas where no de-watering has taken place and the local authority has jurisdiction, is monitoring and has control over the groundwater levels in the areas under consideration; or
- 100 m in areas where de-watering has taken place of where the local authority has no jurisdiction or control over groundwater levels.
The Design-Level investigation (or otherwise known as Phase II dolomite stability investigation or footprint investigation) shall be carried out where;
- required in terms of Table 2 of SANS1936-1:2012
- additional investigation is required for particular types of development, if not included in the Feasibility-Level investigation
- the Feasibility-Level investigation identifies the need for additional information or confirmation of the findings of that investigation, particularly with regard to the inherent hazard class of the site or parts thereof
- further geotechnical information is required for the design of foundations, structures of infrastructure
- deemed necessary by the competent person
The investigation methodology, evaluation and reporting should be in accordance with SANS1936:2012 and the latest NHBRC manual.