Chapter 15.30
EXCAVATION AND BACKFILL FOR TRENCHES

Sections:

15.30.010    General.

15.30.020    Trench safety.

15.30.030    Disposal of materials.

15.30.040    Engineered fill material.

15.30.050    Testing.

15.30.060    Blasting.

15.30.010 General.

This chapter covers excavation and backfill of trenches for the installation of storm sewer, sanitary sewer, water lines, electrical lines, and gas lines in streets and subdivisions. Due to varying ground composition, structure, and collapsible soils, excavation and engineered backfill for trenches shall comply with the APWA Standard Specifications or better as required or deemed needed based on review, inspection, and determination by the city engineer or his/her designee. All OSHA requirements must be maintained in trenches at all times. [Ord. O-13-2015 § 1 (Exh. A); Ord. O-03-2010 § 1 (Exh. A § 6.010)].

15.30.020 Trench safety.

All construction shall be done in accordance with the provisions of the Utah State Industrial Commission and OSHA regulations. No trenches shall be left open at any time unless guarded with adequate barricades, warning lamps and signs.

When required, excavation shall be braced and shored to support the walls of the excavation to eliminate sliding and settling and as may be required to protect the workers, the work in progress, and existing utilities and improvements. All such sheeting, bracing and shoring shall comply with the requirements of the Utah State Industrial Commission and OSHA.

Any injury or damage resulting from lack of adequate bracing and shoring shall be the responsibility of the developer/contractor and the developer/contractor shall, at his/her own expense, effect all necessary repairs or reconstruction resulting from such damage. No inspections will be done in unsafe trenches and will be the cause for immediate shutdown at the project. [Ord. O-13-2015 § 1 (Exh. A); Ord. O-03-2010 § 1 (Exh. A § 6.020)].

15.30.030 Disposal of materials.

All excavation material which is not required for or is unsuitable for backfill shall be immediately removed from the area and not obstruct streets, sidewalks and driveways.

Gutters and irrigation ditches shall be kept clean of excavated material. [Ord. O-13-2015 § 1 (Exh. A); Ord. O-03-2010 § 1 (Exh. A § 6.030)].

15.30.040 Engineered fill material.

Engineered fill (Type A1 or A2 as defined by AASHTO) shall be required backfill for all trenches in the city right-of-way or public utility easements containing city owned and maintained utilities. The contractor is responsible for supplying gradation reports showing proper gradation to meet A1 or A2 classification. [Ord. O-13-2015 § 1 (Exh. A); Ord. O-03-2010 § 1 (Exh. A § 6.040)].

15.30.050 Testing.

Tests to determine acceptability of backfill placed will be done by a firm hired by the developer. The testing company/developer will use standard procedures of the American Society of Testing Materials (ASTM) and/or American Association of State Highway Transportation Officials (AASHTO). Compaction tests will be required at least every 100 feet per lift per trench. Each lift shall be six to 12 inches as determined by Eagle Mountain City and Eagle Mountain City’s testing firm. Lift height will depend on the equipment and material used and the contractor’s ability to properly compact the material. If the backfill so tested does not meet the requirements of this chapter, the trench shall be re-excavated and the backfill replaced in accordance with this chapter. [Ord. O-13-2015 § 1 (Exh. A); Ord. O-03-2010 § 1 (Exh. A § 6.050)].

15.30.060 Blasting.

Blasting will not be allowed except by permission from the city engineer or his/her designee as directed by the fire chief. The contractor shall comply with all laws, ordinances, and applicable safety code requirements and regulations relative to the handling, storage, and use of explosives and protection of life and property. He/she shall be fully responsible for all damage attributable to his/her blasting operations.

Excessive blasting or overshooting will not be permitted and any material outside the authorized cross-section which may be shattered or loosened by blasting shall be removed by the contractor. [Ord. O-13-2015 § 1 (Exh. A); Ord. O-03-2010 § 1 (Exh. A § 6.060)].