R1-IMAT Grangeville Air Center Retardant Retention Pond

Amendment 1 clarifies base gravel payment, adds specification for piping, adds bonding clauses  for bid guarantee, performance and payment bonds. Extends bid closure to 9/12/2014 4 pm PDT.

Description of Work: Grangeville Air Center Retardant Retention Pond

Furnish all labor, materials, equipment, supervision,structures and transportation necessary to complete the construction of improvements at Forest Service facilities, Grangeville Air Center. Work consists of excavation and disposal of material of existing pond, construction of an HDPE lined lagoon, construction of two cast in place concrete diversion structures to separate storm water flows from retardant drainage, installation of culverts, both HDPE and CMP and site cleanup and limited asphalt edge repair.

The main diversion structure will have 2 side gates to divert the storm water or wash down water different directions.

During storm events the water that enters the grassy swale from the west will flow to the diversion structure #2 which will divert the storm water to the north to the grassy swale in an 18 inch culvert (new). The storm water from the west will not enter the new retardant retention pond. Storm water coming from the paved and concrete tarmac will be directed to the new concrete apron to the new concrete diversion structure #1 and be directed to the existing 18 inch culvert that directs the flow north of the site.

During air operations, the slide gates will be positioned to divert any wash down and any accidental spills to the retention pond for storage until such time at this material can be disposed of. In the case that the slide gates are not repositioned for storm water, there will be an overflow from the pond to diversion structure #2 to allow any water to be diverted north to the grassy swale.

The operations of diversion structure #1 are manual with no electrical controls provided.

Project Location: The project is located at the Grangeville Airport, Nez Perce - Clearwater National Forests, 111 Airport Road, Grangeville, Idaho (Section 18, Township 30 North, Range 3 East, Boise Meridian, Idaho County).

Price Range The Government's estimate is between $100,000 and $250,000.

Pre-Bid Tour None

Pre-Bid Conference None

Start Work
It is expected that work will begin October 1, 2014 and must finish by June 15th 2015. It is expected that work will likely commence in the spring of 2015 and run continuously.