Natural Attenuation Area means a dry flat-grassed meadow or open area with existing vegetation that is not subject to erosion.

Sediment means solid material, both mineral and organic, that is in suspension; is being transported; or has been moved from its site of origin by air, water, gravity, or ice and has come to rest on the earth surface.

Sediment Control Device means a settling pond, excavated sediment trap or basin, dewatering trap, or temporary sediment control measure according to OPSS 805.

Uncontaminated Water means any water that does not contain any deleterious substances or class of substances as defined under Section 34(1) of the Fisheries Act, and will not degrade the quality of the receiving water.

518.07               CONSTRUCTION 

518.07.01          Disposal of Water

Water shall be disposed of so as not to be injurious to public health or safety, property, the environment, fisheries, or any part of the work completed or under construction. Dewatering operations shall be directed to a sediment control device or natural attenuation area prior to discharge to watercourses. If a natural attenuation area is used, a minimum 15 m setback shall be maintained from the receiving watercourse. When water is discharged to a watercourse, the water discharged shall be done in a manner that does not cause erosion or other damage to adjacent lands.

When required, a permit issued by the Ministry of the Environment (MOE) for taking water from a groundwater source shall be obtained.

518.07.02         Surface Drainage

Gutters shall be kept clear at all times for surface drainage. The flow of water shall not be directed across or over pavements or sidewalks, except through approved pipes or properly designed and constructed methods.

To protect against adverse impacts resulting from erosion and sedimentation, surface drainage from dewatering operations shall be intercepted and controlled using properly designed filtering or impoundment methods or both.

518.07.03         Settling Ponds and Sediment Traps or Basins

Settling ponds and sediment traps or basins shall be designed, constructed, and maintained according to OPSS 805 and as specified in the Contract Documents.

518.07.04      Temporary Erosion and Sediment Control Measures

The installation, maintenance, and removal of temporary erosion and sediment control measures shall be according to OPSS 805 and as specified in the Contract Documents.

518.07.05        Management of Excess Material

Management of excess material shall be according to the Contract Documents.