804.1 Construction Inspection Guidance for Sec 804
Description (Sec 804.1)
Topsoil may be placed in areas where the existing soil will not support vegetation and where a quick growth of grass or sod is necessary to prevent erosion or to improve appearance. This item is usually used in islands, medians, and on slopes in highly improved urban areas where it is impracticable to build the fertility of the soil with fertilizer. Rock or shale cuts may require benching to hold the topsoil on the slope. The plans show the location on which the topsoil is to be placed, the depth and the volume of topsoil required in cubic yards (cubic meters) and any special conditions for placement of the topsoil. A minimum of six inches of topsoil is recommended where it is used.
Topsoil must be inspected and approved by the Construction & Materials Division. Inspection will normally be made at source; however, source approval in no way relieves the contractor from placing acceptable topsoil. The construction inspector must visually inspect topsoil as it is placed to ensure that the material substantially conforms to the intent of specification.
Construction Requirements (804.3)
It is important that the area on which topsoil is to be placed be raked or otherwise loosened just before placing topsoil. Otherwise the layer of newly placed topsoil may slip off through failure to bond with subsoil. Topsoil should not be handled when it is so wet that it will become densely compacted during placement. Sufficient depth must be placed to allow for future settlement. The surface of topsoil areas should be in condition to permit immediate seeding.
Method of Measurement (804.4)
Measurement is to be made in place. The area times the average depth as determined by the engineer quantifies the total to be paid. Depth is determined by digging frequent test holes back of the spreading operation at random intervals to ensure that plan depth is being placed. Results of these depth checks are to be recorded in the field inspector's diary.
Basis of Payment (804.5)
No additional information is provided.