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When more than one class, size, type, or gage is specified in the bid schedule for any pay item, letter suffixes will be added to the item number to differentiate between the items to be bid upon.

Section 604.-MANHOLES, INLETS AND CATCH

BASINS

Description

604.01 This work shall consist of the construction of manholes, inlets and catch basins in accordance with these specifications, and in reasonably close conformity with the lines and grades shown on the plans or established by the Engineer.

Materials

604.02 Materials. Concrete for these structures shall meet the requirements of Section 601-Structural Concrete. Other materials shall meet the requirements specified in the following subsections:

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When the location of manufacturing plants allows, plants will be inpsected periodically for compliance with specified manufacturing methods, and material samples will be obtained for laboratory testing for compliance with materials quality requirements. This may be the basis for acceptance of manufacturing lots as to quality.

All materials will be subject to inspection for acceptance as to condition at the latest practicable time the Engineer has the opportunity to check for compliance prior to or during incorporation of materials in the work.

Construction Requirements

604.03 Construction Requirements. Concrete construction shall conform to the requirements for structural concrete. When shown on the plans, concrete in slab covers, and all other portions of the structure exposed in the final work, shall be colored by the addition of sufficient emulsified carbon black to give the shade required by the Engineer. To determine the quantity of carbon black required, the Contractor, if so directed by the Engineer shall cast, at his own expense, five sample blocks of concrete 6 by 6 by 4 inches, adding varying quantities as directed so that the required shade may be obtained. The finished surface shall present a neat and smooth appearance and shall have a uniform color.

Metal frames shall be set in full mortar bed. Pipe sections shall be flush on the inside of the structure wall and project outside sufficiently for proper connection with next pipe section. Masonry shall fit neatly and tightly around the pipe.

When grade adjustment of existing structures is specified, the frames, covers, and gratings shall be removed and the walls reconstructed as required. The cleaned frames shall be reset at the required elevation. Upon completion, each structure shall be cleaned of any accumulations of silt, debris, or foreign matter of any kind and shall be kept clear of such accumulation until final acceptance of the work.

Excavation and backfill shall be done in accordance with subsection 206.07.

Method of Measurement

604.04 Standard manholes, inlets and catch basins, both new and reconstructed as applicable, will be measured by the unit. Any additional concrete, reinforcing steel, or masonry required for authorized increases in heights of structures paid for under this section and in excess of the standard height shown on the plans will be measured and paid for under sections 601 and 602 as applicable. Structures noted on the plans as "junction boxes" will be measured for payment as manholes.

The number of concrete covers, pairs of metal frames and gratings, and pairs of metal frames and covers will be measured as acceptably completed.

The number of existing manholes, inlets, and catch basins adjusted as directed will be measured as acceptably completed.

Basis of Payment

604.05 The accepted quantities of pay items from the list below that appear in the bid schedule, determined as pro

vided above, will be paid for at the contract unit prices. Excavation and backfill will be measured and paid for as provided in Section 206-Structure Excavation. Payment will be made under:

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604(5) Metal frames and gratings, type

Pair.

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If more than one type is specified for a pay item, letter suffixes will be added to the item numbers to differentiate between such items to be bid upon.

Section 605.-UNDERDRAINS

Description

605.01 This work shall consist of constructing underdrains using pipe and granular filter material, underdrain pipe outlets, and blind drains using granular material in accordance with these specifications and in reasonably close conformity with the lines and grades shown on the plans or established by the Engineer.

Materials

605.02 Material. Materials shall meet the requirements specified in the following subsections:

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Perforated bituminized-fiber pipe
Bituminized-fiber pipe..

Corrugated aluminum alloy pipe for
underdrains

Granular backfill filter material

706.13

706.12

707.07

703.01(b)

Aggregate requirements will be shown on the plans or in the special provisions.

When the location of manufacturing plants allows, the plants will be inspected periodically for compliance with specified manufacturing methods, and material samples will be obtained for laboratory testing for compliance with materials quality requirements. This may be the basis for acceptance of manufacturing lots as to quality.

All materials will be subject to inspection for acceptance as to condition at the latest practicable time the Engineer has the opportunity to check for compliance prior to or during incorporation of materials in the work.

Construction Requirements

605.03 Pipe Installation. Trenches shall be excavated to the dimensions and grades required by the plans or as directed. A minimum 6-inch bedding layer of granular backfill material shall be placed and compacted in the bottom of the trench for its full width and length.

Subdrainage pipe of the type and size specified shall be embedded firmly in the bedding material.

Perforated pipe shall normally be placed with the perforations down and the pipe sections shall be joined securely with the appropriate coupling fittings or bands.

Non-perforated pipe shall be laid with the bell end upgrade and with open joints wrapped with suitable material to permit entry of water, or unwrapped as may be specified. Upgrade end sections of all subdrainage pipe installations shall be closed with suitable plugs to prevent entry of soil materials.

After the pipe installation has been inspected and approved, granular backfill material shall be placed to a height of 12 inches above the top of pipe. Care shall be taken not to displace the pipe or the covering at open joints. The remainder of the granular backfill material shall then be placed and compacted in 6 inch maximum layers to the required height. Any remaining portion of trench above the granular backfill shall be filled with either granular or impervious material, as may be specified, and thoroughly compacted.

605.04 Underdrain Outlets. Trenches for underdrain outlets shall be excavated to the width and depth shown on the

plans or as otherwise indicated. Pipe shall be laid in the trench with all ends firmly joined by the applicable methods and means. After inspection and approval of the pipe installation the trench shall be backfilled in accordance with subsection 603.08.

605.05 Blind Drains. Trenches for blind drains shall be excavated to the width and depth shown on the plans. The trench shall be filled with granular backfill material to the depth required by the plans. Any remaining upper portion of trench shall be filled with either granular or impervious material in accordance with subsection 603.08.

Method of Measurement

605.06 Underdrains and outlets will be measured by the linear foot for pipe of the type and size specified. Blind drains will be measured by the linear foot including all excavation and backfill material required.

Granular backfill material, when specified in the contract as a pay item will be measured in place by the cubic yard, completed and accepted. Cross sectional measurements will not exceed the neat dimensions shown on the plans or directed by the Engineer.

Excavation for underdrain pipe will be measured and paid for as provided in section 206.

Basis of Payment

605.07 The accepted quantities of pay items from the list below which appear in the bid schedule, determined as provided above, will be paid for at the contract unit prices therefor.

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