November 5, 2019

Addendum #2

November 18, 2019

The additional site visit has been changed to December 4, 2019 at 1:00 p.m. at the DesPlaines Treatment Plant located at 800 Krause Dr, Buffalo Grove.

November 11, 2019

The bid opening date has been changed to December 10, 2019 at 11:00 a.m. 

An additional site visit will be held November 20, 2019 at 9:00 a.m. at the DesPlaines Treatment Plant located at 800 Krause Dr, Buffalo Grove.

Addendum #1 Addresses the questions raised during our initial pre-bid walk-through at the site on 11/6/19, as well as provide clarity to the fence installation.

There are two attachments included with the addendum 1-A, and 1-B. 

Please note: the objective of the attachments is to get the basic concept of what we are looking for which is to construct a fence so to match as closely as possible to the existing east and west fences at the job site.

Question about Liquid Damages:

They have been withheld from this project. However, the owner expects the contractor:

1. Use all means necessary to protect fence materials before, during and after installation and to protect the installed work and materials of all other trades.

2. In the event of damage, immediately make all repairs or replacements necessary to the approval of the Architect/Engineer and at no additional cost to the Owner.

Standards of manufacture:

Comply with specifications and the standards of the Chain Link Fence Manufacturer's Institute.

1. Standard guide for metallic-coated steel chain link fence fabric.

2. Industrial steel guide for fence rails, posts, and accessories.

FENCING TYPE – GALVANIZED CHAIN LINK FENCE

A. Overview: This work shall consist of constructing an 8’ high approx. 1,000 ft. long galvanized chain link perimeter fence. This fence will connect to existing fencing of the same type located on both the east and west end of the site. A swinging gate will need to be installed at the location designated in attachment 1-A to allow utility vehicle access. There is a section where the fence line will need to cross over a shallow creek, also shown on 1-A. Below are descriptions of the materials specified for the project. For more details, please refer to the attachments, and to IDOT sections 1006.26, 1006.27 and 1006.28.

9-gauge x 2” mesh steel galvanized wire fencing fabric.

1 5/8” O.D. SS40 galvanized steel pipe (top & brace) fence rails.

2 ½” O.D. SS40 galvanized steel pipeline posts.

3” O.D. SS40 galvanized steel pipe terminal posts.

7-gauge coil spring bottom tension wire.

8’ high x 10’wide split swinging utility vehicle access gate using same quality galvanized materials.

Drop rod latch system to secure access gate.

8’ high suspended gate or panel secured between posts to span across approx. 22ft. wide at the creek.

B. General: Prior to constructing the fence, the area along the line of the fence should be cleared. The finished fence shall be plumb, taut, true to line and ground contour, and complete in every detail. Where directed, the Contractor may be required to stake down the chain link fence at several points between posts.

Installation to conform to ASTM F-567 and as described in these specifications. Installation shall be made in a workmanlike manner by skilled mechanics, experienced in construction of this fence type.

C. Installing Posts: Posts shall be spaced apart 10’ maximum and set in concrete at a depth of 42”. Class SI concrete shall be used. On terminal (end, corner, pull, brace) and gate posts, the post tops where required and brace rail clamps around the posts shall be placed before setting the posts in concrete bases. A line drawn across from the top of one gate post to the other shall be level, regardless of the grade at the ground line. If the ground is not level, the upgrade post shall be set first to get the proper height for the downgrade post. Fence shall not be erected until the concrete encasement around the posts has cured for at least seven days.

D. Post Tops: All hollow pipe and tube type posts shall be fitted with post tops. The bases of the post tops shall have flanges which fit around the outside of the posts and shall be secured in place.

E. Braces: When required by the plans, braces shall be placed 12” down from the top of the terminal posts and shall extend from the terminal (end, corner and pull) posts and gate posts to the brace posts. The braces shall be securely fastened to the post and trussed from brace post back to terminal posts with 3/8” round rods with a turnbuckle.

F. Fabric: The fabric shall be unrolled on the outside (tree-lined side) of the fence line with the bottom edge of the fabric against the posts.

G. Stretcher bars: These shall be galvanized flat steel bar not less than 1/4 x ¾” and the stretcher bar bands shall be galvanized flat steel bar not less than 1/8 x 1” with an 3/8” (M10) galvanized carriage bolt.

H. Tension Wire: The top and bottom tension wire shall be placed, stretched taut, and secured at ends to all posts in a satisfactory manner before fabric is placed. Tension wire shall be stretched tight with galvanized turn buckles spaced at intervals of not more than 1000 ft.

I: Access Gate: The utility vehicle access gate shall be installed at the location shown on attachment 1-A. The split swinging gate doors should be hung on gate fittings as shown on the plans. The lower hinge (ball and socket type) shall be placed on top of the concrete in which the gate post is set. The socket for the drop latch shall be set in concrete so that the plunger pin will fit perfectly in the socket when the gate is in a closed position. Gates shall be set to swing open on the south side (tree-line side) and shall be provided with gate stops as specified or shown on the plans. Gate keepers shall be provided to hold gates when in open position and shall be located and installed as directed by the Engineer. All hardware shall be thoroughly secured, properly adjusted and left in perfect working order. Hinges and diagonal bracing in gates shall be adjusted so that gates will hang level.

J: Creek Crossing: The water in this creek is typically shallow and static. In order to continue the perimeter fence line across the creek as shown in attachment 1-A, the contractor shall obtain or build a fence panel capable of spanning the 22 to 23-foot creek. The fence panel shall contain six vertical posts spaced equal distance apart connected to a top and bottom rail. Between each section a cross brace shall be installed that extends diagonally from the top of each vertical post to the bottom of the adjacent post. At the bottom a tensioning cable shall be installed with turnbuckles. The panel shall be suspended a few inches above the water and connected to capped posts on either side of creek that are a minimum O.D. of 3”.  The installer shall determine the post locations and overall length of the panel. Keep in mind this panel may need to withstand the pressure of snowpack and possible debris. No posts should be installed in the creek water. The posts should be encased in concrete on each side of the creek bed at a depth necessary to provide continued support in moist soil.

K. Existing Fence Connections: The new fence shall join the existing fencing on the east and west sides of the site. A corner post with brace post should be set at the junction and braced the same as described for corner posts as shown on attachment 1-B.

L. Clean up: The contractor shall clean the jobsite of excess materials; post hole excavations shall be removed from job site and disposed of properly.

M. The Fence location has been marked with stakes on the jobsite.  The stakes do not denote post locations, rather the fence line to follow, See Attachment 1-A 2019 DPR FENCE LINE.

N. A detailed drawing for the fence construction, posts and gate is included as

Attachment 1-B 2019 DPR FENCE INSTALLATION DETAILS.