Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 20·4.5
Ground water alteration during excavation and water-borne contaminants
Excavation work for foundations and services can alter ground water flow. Where water-borne contaminants are present, either drainage must be provided or other effective means must prevent transportation of contaminated water to foundations, building, or services.
4.5 General excavation work for foundations and services can alter the passage of ground water which flows through the site. Where water borne contaminants are present in the ground, either the ground to be covered by the building should be drained, or some other effective means should be taken to prevent the transportation of such water borne contaminants to the foundations or into the building or its services.
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