GLEN_18-1107_SOW_Addendum.pdf

Statement of Work

Addendum 1

Project Number: GLEN 18-1101

Repair Electrical-HVAC at Emergency

Power Plant, B600

Schriever AFB, Colorado

18 SEPTEMBER 2019

GLEN 18-1101 Page 2

1.0 BACKGROUND:

A Statement of Work Addendum is necessary due to requirement development deficiencies with the subject project. The following changes are hereby incorporated into the original contract scope.

2.0 SCOPE OF WORK:

The Contractor shall provide all labor, tools, and materials to complete all work represented by these changes. The Contractor shall still adhere to the original contract documents, including the original Statement of Work and Specifications. All material and testing requirements from the original contract scope remain unchanged. The Contractor shall provide the Government with complete construction, and warranty for this project, to include the revised requirements.

3.0 MODIFIED REQUIREMENTS:

2.3.3.b. The underground portion of the conduits shall be replaced.

2.3.3.d. The underground portion of the conduits shall be replaced.

2.3.3.e. Drawings CD-101, and CP-101 show that the concrete walkway should be removed and the pads reused. Pads shall also be removed in order to ease replacement of the conduit and grounding ring.

2.4.1 Drawings_PDF_Transformers Replacement – Sheet CP-101, shows concrete pads to be protected in place, this is incorrect. Pads shall be removed and new pads installed for new equipment.

2.4.2. New concrete Pads for Transformers shall be sized to fit new equipment but must fit in existing transformer yard with proper spacing. Pads shall meet specifications as outlined below in 2.4.4 and 2.4.5.

2.4.3. Poor new concrete walkways in transformer yard as shown on drawing:

Drawings_PDF_Transformers Replacement – Sheet CP-101. Expansion joints of the

Concrete walkway shall be followed to match new pads.

2.4.4. Transformer Pad Concrete Material Specifications:

a. Composed of fine aggregate, coarse aggregate, Portland cement, and water so proportioned and mixed as to produce a plastic, workable mixture.

b. Fine aggregate: hard, dense, durable, clean, and uncoated sand. Removed from current work: Contractor shall assume existing chilled water supply and return lines within project footprint are adequately sized to support the proposed configuration and increase in personnel.

c. Coarse aggregate: reasonably well graded from 3/16 inch to 1 inch.

d. Fine and coarse aggregates: free from injurious amounts of dirt, vegetable matter, soft fragments, or other deleterious substances.

GLEN 18-1101 Page 3

e. Water: fresh, clean, and free from salts, alkali, organic matter, and other impurities.

f. Concrete associated with electrical work for other than encasement of underground ducts: 30 MPa 4000 psi minimum 28-day compressive strength unless specified otherwise.

g. Slump: Less than 4 inches. Re-tempering of concrete will not be permitted.

h. Exposed, unformed concrete surfaces: smooth, wood float finish.

i. Concrete must be cured for a period of not less than 7 days, and concrete made with high early strength Portland cement must be repaired by patching honeycombed or otherwise defective areas with cement mortar as directed by the

Contracting Officer.

j. Air entrain concrete exposed to weather using an air-entraining admixture conforming to ASTM C260/C260M.

k. Air content: between 4 and 6 percent.

2.4.5. Transformer Pad Construction Specifications:

a. Mount transformer on concrete slab as follows:

b. Unless otherwise indicated, provide the slab with dimensions at least 8 inches thick, with reinforcing 6 by 6 inches - W2.9 by W2.9 mesh placed uniformly 4 inches from the top of the slab.

c. Place slab on a 6 inch thick, well-compacted gravel base.

d. Install slab such that top of concrete slab is approximately 4 inches above the finished grade with gradual slope for drainage.

e. Provide edges above grade with 1/2 inch chamfer.

f. Provide slab of adequate size to project at least 8 inches beyond the equipment.

g. Stub up conduits, with bushings, 2 inches into cable wells in the concrete pad.