Amendment 0001 - Spring Brook Revised Construction Specification.pdf

May 2010 5

12. ITEMS OF WORK AND CONSTRUCTION DETAILS

The items of work to be performed in conformance with this specification and the construction details are:

A. Bio-Engineering

(1) This item consists of the furnishing and installation of the planting materials as shown on the drawings.

(2) Fifty (50) percent of the live stakes shall be Streamco Willow (Salix purpurea). The remaining live stakes shall be Redosier Dogwood (Cornus sericea).

(3) Live stakes shall be placed in a 3 foot by 3 foot grid pattern within the areas shown on the drawings and as directed by NRCS or Erie County SWCD personnel in the field. Live stakes in the flood terrace shall be planted in a 2 foot by 2 foot grid pattern and as directed by NRCS or Erie County SWCD personnel in the field.

(4) The contractor shall be responsible for identifying and supplying of the necessary plant materials.

(5) Payment for all bio-engineering plantings shall be at the lump sum price for all required plantings.

10. ITEMS OF WORK AND ADDITIONAL CONDITIONS

The items of work to be performed in conformance with this specification and the construction details are:

A. Bid Item 7 Subsurface Drain, (slope drainage)

1) This item shall consist of all the work necessary to construct the one (1) - 6 inch diameter perforated drain conduit at the west upper bank as shown on the drawings. This item also includes the 18 inch diameter conduit outlet section of schedule 40 PVC with a small animal guard and connections to the two (2) existing clay and catch basin. This item shall also include all fittings as needed to complete the drain.

2) In Section 2, MATERIALS, the material to be used for the subsurface drain shall be 125 L.F. of 6 inch inside diameter HDPE corrugated and perforated pipe meeting ASTM F-405. The outlets shall be 80 L.F.

of 18 inch inside diameter PVC schedule 40, non-perforated pipe meeting ASTM D-1785, and 20 L.F. of 6 inch inside diameter PVC schedule 40, non-perforated pipe meeting ASTM D-1785. A small animal guard is required at each outlet. The material for the crushed stone backfill is specified in Part 5. Fernco™ or equivalent couplers shall be used to connect the catch basin to the PVC outlet and to connect existing drains to the catch basin they will either be knocked out of grouted.

3) In Section 3, EXCAVATION, The minimum trench bottom width shall be 24 inches. In all cases excavation spoils must be stockpiled at least 2 feet from the top of the trench.

4) In Section 4, BEDDING, the conduits shall be bedded in a notch formed at the bottom of the excavated trench as shown on the drawings. The trench bottom shall be firm enough to adequately support the conduit. Suitability of the trench bottom shall be determined the Engineer or designated NRCS representative. Where the trench bottom is not suitable, it shall be over excavated and backfilled with crushed stone as bedding.

5) In Section 7, BACKFILLING, the perforated conduit for the subsurface drain shall be backfilled as shown on the drawings up to a minimum of 24 inches above the top of the conduit with clean crushed stone meeting NYS DOT Specification 703 Coarse Aggregate (Table 703-4) Type 2: NYS DOT Type 2 Coarse Aggregate (crushed stone): 100% finer than 37.5 mm (1-½ in.) 90-100% finer than 25.0 mm (1 in.) 0-15% finer than a

12.5 mm (½ in.) Fill above the required clean crushed stone depth shall be crushed stone or bank run gravel as specified in the Earthfill Specification. Crushed stone or gravel shall be compacted by means of a manually directed power tamper in lifts not to exceed 6 inches. Earth backfill outside the minimum required crushed stone shall be suitable excavation spoils as specified.

6) The CATCH BASIN shall be a 24 inch square catch basin of precast concrete with a minimum height/depth of 7 feet. The depth shall be achieved by having a 4 foot base with the outlet and 6 inch clay drain pipe connecting to it, and a riser that is to have the 12 inch clay drain connecting in shall make up the rest of the depth needed for the basin. The catch basin shall have a one (1) foot deep bedding of clean crushed stone meeting NYS DOT Specification 703 Coarse Aggregate (Table 703-4) Type 2: NYS DOT Type 2 Coarse Aggregate (crushed stone): 100% finer than 37.5 mm (1-½ in.) 90-100% finer than 25.0 mm (1 in.)

0-15% finer than a 12.5 mm (½ in.) supporting it. The catch basin shall also have a bicycle safe grate at the top and should meet all requirements shown on the drawings, or determined by an inspector or NRCS representative.

7) In Section 9, MEASUREMENT AND PAYMENT, payment for Bid Item #5 shall be by Method 1. Payment shall be at the contract unit price for the total length of all conduits installed and shall be the total compensation for all excavation, crushed stone backfill, compaction and fittings.