Channel Creek Plan Set.pdf

ITEM NO.

DESCRIPTION UNIT EST. QTY.

15101

Mobilization Lump Sum ALL

15201

Construction survey and staking, method I, tolerance C Lump Sum ALL

15713

Soil Erosion & Pollution Control Lump Sum ALL

20101

Clearing and grubbing *Acre

0.6

20301

Removal of existing 54”x125’ culvert *Each 1

20415

Unsuitable Excavation *Cubic Yard 1254

20962

Structure excavation *Cubic Yard 560

20963

Structural backfill *Cubic Yard 344

25101

Placed riprap, class 6 *Cubic Yard 50

32201

Aggregate surface course, grading D, compaction method B (commercial source)

*Ton 155

55201

Structural concrete class A(AE) *Cubic Yard 29

60304

12’ span, 6”3” rise, galvanized steel structural plate arch, .111 inch thickness, 6”x2” corrugations

*Foot 65

62501

Seeding, dry method *Acre 0.4

*=Contract Quantity

Construction Timing

1. The project shall be constructed between September 7th and October 31st of 2010 or

September 6th and October 31st of 2011. In stream work (including stream bypass installation and removal) may only be conducted between July 1st and September 30th

Temporary Traffic Control

2. A four week road closure will be allowed for this project for the installation of the new culvert and removal of the old culvert. Signs shall be posted at the beginning of Baker Lake Highway to notify the public. A sign shall also be posted identifying the last turnaround for larger vehicles and vehicles with trailers. Foot travel shall be permitted through the construction site for access to the trail at the end of the road as long as it can be done safely. A closure sign with the dates shall be posted 14 days prior to closure. Submit a traffic control plan for approval by the CO prior to construction. All traffic control is incidental to item 15101.

Construction Staking

3. The physical conditions portrayed in the drawings are the result of site investigations by survey. Staking shall include clearing limits, slope stakes for the stream channel and elevation and alignment for the arch. Staking notes to be provided to the contractor. All staking is an indirect cost to item 15201.

Soil Erosion & Pollution Control

4. Soil erosion and pollution control shall be done in accordance with section 157.03 of the specifications and is an indirect cost to item 15713. Approved erosion control measures shall be in place prior to construction operations.

Clearing & Grubbing

5. Clearing limits are 3’ beyond the limits of excavation and shall be staked before any clearing begins. Any clearing outside the limits shall be approved by the CO first. All felled trees shall be placed in the adjacent forest. All brush, woody debris and topsoil shall be hauled to the waste site shown on the Location Map. Only trees within the designated clearing limits may be cut. The CO may approve cutting of trees outside the clearing limits if deemed necessary.

Larger trees shall be salvaged and placed in the finished stream channel as directed by the

CO.

In‐Channel Work & Dewatering

6. The existing 54” culvert shall remain in place and be used as the stream bypass until the new stream channel has been constructed. Both ends of the new stream channel shall have barriers to prevent turbid water from entering the active stream during construction. Once the new stream channel is complete, it shall be filled slowly to allow settling before the barriers are removed and it is released into the active stream. The contractor shall submit a detailed dewatering plan to the CO for approval. Dewatering is an indirect cost to item

60304.

Removal of Culvert, Excavation & Embankment, Stream Channel and Riprap

7. The 54” existing culvert shall be completely removed and disposed of off Government land and in compliance with state and local laws. Backfill of the trench after the culvert is removed shall comply with section 204 of the specifications. The excavation & backfill and disposal of the culvert are indirect costs to item 20301.

8. Item 20415 includes all the stream channel excavation. The new stream channel bed shall be constructed to match the nature and integrity of the existing stream channel and is an indirect cost to item 20415.

9. Item 20962 includes all excavation for the bottomless arch and footings including the 6” for bedding material. This item also includes the excavation for riprap. All excavations shall be approved by the CO before placing bedding or riprap.

10. The waste area for all unsuitable and excess excavation is shown on the location map.

11. Item 20963 includes the backfill for the bottomless arch structure including the 6” of compacted crushed bedding under the footings. Embankment material may be obtained from suitable on‐site excavation. The existing road surfacing may be conserved and used as foundation bedding and structural backfill.

12. The neat line for determining the minimum quantities for excavation and backfill is shown on

Sheet 6. Any additional excavation done for safety or access reasons shall be backfilled and compacted according to section 204 of the specifications.

13. Riprap may be obtained from conserved on‐site excavation or from a commercial source and is an indirect cost to item 25101.

14. Item 30111 includes placing 6” of crushed aggregate surfacing matching the width and grade of the existing roadway (minimum 20’). Crushed aggregate shall be obtained from a commercial source.

Structural Plate Bottomless Arch and Footings

15. Installation of the arch shall be in accordance with the manufacturer’s recommendations, the

“Installation Manual for Corrugated Steel Pipe, Pipe Arches & Structural Plate” by the

National Corrugated Steel Pipe Association, and the specifications, except that the excavation and backfilling shall be in accordance with section 209 of the Forest Service Supplemental

Specifications.

16. Item 60304 includes furnishing and installing a 12’x6’‐3” galvanized steel structural plate arch with 6”x2” corrugations and .111” thick.

17. Footings shall be cast in place as shown on the plans. Footings, rebar, and filler grout are indirect costs to item 55201.

Seeding

18. All disturbed soil areas within the project area shall be seeded and mulched. All mulch shall consist of weed free straw or wood strand.