A.
Limits of excavation.
(1)
Excavations shall be made to the approved lines which shall be of sufficient width outside the structures to give room for placing and removing forms for concrete and for forming pipe joints. Excavations for all structures shall not be plowed, scraped, or machine-dug closer than three inches to the finished subgrade. The last three inches of depth for all structures including pipe shall be removed with pick and shovel to the exact lines and grades just before placing foundation material, or pipe supports. Due allowance shall be made for excavating to a depth below the pipe invert to accommodate foundation material or pipe supports. Bell holes shall be hand excavated for any pipe with a bell dimension larger than the pipe barrel.
(2)
In general, the widths of pipe trenches shall not be wider than the outside diameter of the pipe barrel plus two feet at the level of one foot above the top of the pipe unless otherwise approved.
(3)
Blasting for rock excavation will be permitted only on approval of methods and in compliance with applicable federal, state and local regulations.
B.
Storage and disposal.
(1)
Excavated material, which is suitable and approved for backfill and fill shall be placed in storage piles unless or until it can be placed in the work. It shall not be placed close to the sides of excavations, where the weight of the material could create a surcharge on such sides, whether sheeted or not.
(2)
Unsuitable material, or material in excess of that required for fill, backfill or other purposes, including any stored surplus, shall be disposed of away from the sewer construction site.
C.
Sheeting and bracing. Where excavations are made with sides which require supporting, sheeting and bracing shall be used, of sufficient strength to sustain the sides of the excavations and to prevent movement which could in any way injure the work, or diminish the working space sufficiently to delay the work. Sheeting shall be of a material that will not split while being driven. Sheeting and bracing shall conform to the requirements of the "Construction Safety Code" of the Bureau of Engineering and Safety of the New Jersey Department of Labor and Industry, and to OSHA requirements.
D.
Dewatering. The contractor shall provide, operate and maintain satisfactory facilities and equipment including well points, and coffer-dams if necessary, with which to contain, collect and pump all water entering excavations or other parts of the work to suitable places for disposal. All excavations shall be kept free of water until the work or structure to be built therein is completed.
E.
Backfill and fill.
(1)
All backfill and fill under pipes and all structures shall consist of suitable approved foundation material. All other backfill and fill, unless otherwise specified or required, shall consist of a suitable selected and approved earth or sand generally from storage of approved suitable excavated material, free from rejected organic matter, boggy, peaty humus or other unsuitable material such as unconsolidated silt, rubbish waste, ashes or cinders and with less than 15% of size 200 sieve material. If sufficient suitable material for backfill is not available from the excavated material, as determined by the Engineer, the contractor shall procure elsewhere a sufficient quantity of suitable bank run sand gravel and shall furnish and place such material. No frozen earth shall be used for backfill, and all stones more than six inches in the largest dimension shall be removed from acceptable earth for fill.
(2)
Backfills and fills shall be made to the slopes, grades, and elevations shown on the contract drawings. Backfills shall be compacted, as herein under specified, to a density at least equal to that of the adjacent undisturbed soil, so as to avoid future unequal settlement.
(3)
No backfill shall be placed until the structure has been inspected in place and approved. Backfilling shall be carried out as soon as possible after such approval.
F.
Placing and compacting backfill.
(1)
Trenches shall be backfilled from the top of the foundation material to a depth of not less than 12 inches over the pipes using only bank run sand and gravel. Such material shall be uniformly placed on each side of the pipe in six-inch layers, wetted as required, and firmly compacted by approved tamping machines. Care shall be taken not to damage the pipe. After a compacted coverage of 12 inches has been made, the remainder of the trench shall be backfilled and mechanically compacted in twelve-inch lifts, unless otherwise approved by the Engineer, to obtain a maximum 90% Modified Proctor Density to a point three feet below the road surface. From this point, a minimum 95% Modified Proctor Density is required. Smaller lifts shall be required if this density is not obtained. The backfill material shall be wet or dry as required to obtain the required density.
(2)
When the trench is not in or across a dedicated street, or right-of-way, or any other place where pavement is not to be constructed, backfill shall be compacted to obtain a minimum 90% Modified Proctor Density.
(3)
Puddling for compaction will not be permitted except as approved by the Township Engineer. Bulldozing of backfill material into trenches will be prohibited unless it is done in uniformly spread layers, not over 12 inches thick and immediately machine tamped. The developer shall provide material as required to compensate for settlement of backfill and fill.
(4)
When sheeting is being withdrawn, all cavities left thereby shall be filled with suitable granular earth, hosed or tamped in place so as to thoroughly fill all voids.
(5)
The densities referred to above shall be based upon the latest Standard Test Methods for Moisture Density Relations of Soils and Soil Aggregate Mixtures Using 10 lb. Rammer and 18 inches Drop, ASTM Designation D-1557. Density control in the field shall be based on the latest Test for Density of Soil in Place by Sand/Cone Method, ASTM Designation D-1556.
G.
Foundation material.
(1)
Foundation material used for pipe bedding, from a minimum six inch distance below the pipe invert to the lower quarter point of the pipe, shall be bank run sand and gravel or broken stone. Polyvinyl chloride pipe shall use broken stone or gravel. Pipe embedment material from the lower quarter point to 12 inches above the top of the pipe shall be bank run sand and gravel.
(2)
Bank run sand and gravel and broken stone shall conform to the requirements of the New Jersey Department of Transportation, 2007 Revision, Standard Specifications for Road and Bridge Construction, Section 901, Aggregates. Backrun sand and gravel shall be in conformance with Subsection 901.11, Soil Aggregate, Table 901.11-1 Standard Soil Aggregate Gradations, Gradation size I-3 or I-8. Broken stone shall be in conformance with Subsection 901.03, Coarse Aggregate, Table 901.03-1, Standard Sizes of Course Aggregate, Size No. 57 (3/4"). Frozen and lumpy material shall not be used.
(3)
All foundation material shall be placed and compacted as directed and approved by the Engineer.
H.
Construction safeguards. All excavation for sewers and/or house connections shall be adequately guarded with barricades and lights so as to protect the public from hazard. Streets, sidewalks, driveways, curbs, parkways and other public property disturbed in the course of the work shall be restored in a manner satisfactory to the Township of Allamuchy.