102019.3.STATEMENT OF WORK.pdf

STATEMENT OF WORK

KRSM 102019; WO# 54379

Repair/Upgrade Grounding on Pads A&C in MAMS I

August 27, 2010

1. Contractor shall provide and install all materials, hardware and miscellaneous items for a complete and functioning grounding system as described below. All work shall be accomplished in a workman like manner with as little disturbance to existing facilities as possible.

2. The two existing parking pads are in the MAMS I area on Hill AFB, Utah. This area is in the explosive clear zone of the base and the requirements in the

Specification Section 01000, Paragraph 1,14.G shall be followed.

3. The dimensions on Drawings 101 and 102 were made with a measuring wheel.

The contractor is responsible to make his own measurements to verify exact dimensions.

4. There is a total of 12 static ground points in the two parking pads. The contractor shall saw cut the concrete pads as shown in Detail 3 of DWG 103 to remove the existing grounding points. Pad A (Facility 11456) has 10 grounding points and

Pad C (Facility 1350A) has 2.

5. The parking pads are concrete approximately 8 inches thick for Pad A and 6 inches thick at Pad C. To install the new 1/0 bare copper grounding conductor the contractor shall cut the asphalt just to the outside of the concrete pad so only one cut is required for most of the work. The contractor shall remove the asphalt needed and dispose of it at the asphalt site on the north end of Hill AFB. The trench detail on DWG 103 shows a 6 inch wide trench, but if the contractor’s equipment is wider than this the trench will have to be wider.

6. The contractor shall not have both parking pads out of operation at the same time.

7. There shall be a total of 12 ground rods installed, one at each grounding point.

The ground rods will be ¾ inch by 10 feet; copper clad steel.

8. The 1/0 grounding cable shall be run completely around the parking pads in the trench and shall be connected to each grounding point, each electric power source, each lightning protection pole down conductor, and to the transformer secondary ground to the southeast of Pad A. All underground connections shall be made with exothermic welds.

9. The 12 new grounding points may be Model YGT275 by Storm Copper

Components, Co. or Government approved equal. The new grounding points shall be installed so they are flush with the surface of the parking pad. The new grounding points will be exothermically welded into the grounding system for a permanent connection. The concrete for filling in the chunks that were saw cut out shall be 5000 psi concrete. The contractor shall drill each grounding point cutout to install 5 dowels, 3/4” in diameter. The dowels will extend 4 inches into the existing concrete and 9 inches into the new concrete. There will be 2 dowels on each side of the cut and one on the end. The dowels will be about equally spaced apart. The joint between the old and new concrete shall be water proof sealed.

10. At each electric power source a ground bar shall be installed. Several of the electric power sources have an existing ground bar. These ground bars shall be removed and replaced with a new ground bar. There is a total of 7 electric power sources. The ground bars shall be tinned copper ¼ x4x12 inches. The ground bar shall be installed with standoff insulators and may be Model SCGB-5KT-TIN by

Storm Copper Components, Co. or Government approved equal. The ground bars shall be mounted about 4 feet above grade where they will be most convenient for connecting grounding clamps. The ground bars shall be connected to the grounding system with a long barrel, two hole connector that is crimped in two places using a high compression device. The connector shall be fastened to the ground bar using stainless steel hardware; bolt, nut, washer, and lock washer. The conductor from the connector to the grounding system shall be 1/0 bare copper conductor installed in pvc conduit until it is at least 6” below ground level. The conductor shall be exothermically connected to the groun rod located at each location. The contractor shall install one grounding test point access box at each site, total of two. The contractor shall red line the drawings with the location where the test point is installed.

11. The soil removed should be of such a nature that it can be reused for back filling the trench. The contractor shall ensure that there are no rocks over1 inch in the 3 inches of fill directly above the cable. The remainder of the fill shall be compacted in 6 inch lifts. The contractor shall replace the asphalt to the same depth as was removed.

12. The contractor shall have a ground impedance test performed for each parking pad. The ground impedance shall be 25 ohms (or less) to ground. The contractor shall provide a copy of the test results to the Project Manager.