25(1)Where sand, slag or tailings are to be used for fill underground, an employer shall ensure that before the material is used
it has been tested to ensure its suitability for the purpose, particularly with respect to its self-draining characteristics and stability,
sulphide material is not included in the material in quantities that may induce spontaneous combustion, and
the cyanide content in the liquid portion of any tailings is less than 0.005 mg per litre expressed as potassium cyanide.
25(2)Where sand, slag or tailings have been used for fill, an employer shall ensure that the cyanide content in the liquid portion of the effluent from the filled area does not exceed 0.005 mg per litre expressed as potassium cyanide.
25(3)An employer shall ensure that no person goes onto any fill without adequate protection against subsidence of the fill or reaction to physical contact with the fill.