01_Geotech_Report_Subsurface_Information_Addendum_No._1-KC-46A_FTC_Simulator_Phase_2_Facility.pdf

ADDENDUM NO. 1 - SUBSURFACE INFORMATION DOCUMENT

DATE: June 06, 2016

Issued to All Subsurface Information Document Holders of Record

OWNER: United States Army Corps of Engineers

PROJECT: KC-46A FTC Simulator Phase 2 Facility

PROJECT NO.: 89371

DOCUMENT: Subsurface Information Document

This addendum forms a part of the above Document. The original Subsurface Information Document remains intact as modified by the following which will take precedence over any contrary provisions or information in the prior Document.

SUBSURFACE INFORMATION:

Subsurface Exploration- Addendum, Altus Air Force Base KC-46A, FTU/FTC

Simulator Facility Phase 2, Altus, Oklahoma, Standard Testing Project No.: 5316- 3908A1, by Standing Testing and Engineering Company, dated June 6, 2016. This 2 page report addendum with 1 page flysheet contains recommendations from the geotechnical engineer of record for the use of a clay cap around the building as an alternate to a building underdrain system.

Each Subsurface Document holder shall acknowledge receipt of this addendum by affixing their signature below and returning to the address listed below, by noting this supplemental information on their Subsurface Document and by attaching this supplemental information to their Subsurface Document.

Burns & McDonnell Engineering Company Bid Document Controller 9400 Ward Parkway Kansas City, Missouri 64114

ACKNOWLEDGEMENT:

The undersigned acknowledges receipt of this supplemental information.

Document Holder: Document No:

By: Date:

Subsurface Exploration- Addendum, Altus Air Force Base KC-46A, FTU/FTC Simulator Facility Phase 2, Altus, Oklahoma, Standard Testing Project No.: 5316-

3908A1, by Standing Testing and Engineering Company, dated June 6, 2016.

June 6, 2016

Burns & McDonnell Engineering Company, Inc.

9400 Wand Parkway

Kansas City, MO 64114-3319

Attn: Mr. Jason Walker, P.E.

Senior Engineer

Geotechnical Department

Re: Subsurface Exploration- Addendum

Altus Air Force Base KC-46A

FTU/FTC Simulator Facility Phase 2

Altus, Oklahoma

Standard Testing Project No.: 5316-3908A1

Dear Mr. Walker:

Per requested, Standard Testing and Engineering Company (Standard Testing) is pleased to provide the following Clay Cap Recommendations - an Addendum to Altus Air Force Base KC-46A

FTU/FTC Simulator Facility Phase 2 project, Project No. 5316-3908; Dated May 2, 2016.

Clay Cap Recommendations

Underdrain system, Report Section 4.6 (page 18), can be waived if clay cap is placed surrounding building footprint.

Clay cap should:

• be over-excavated at least one foot deep below final grade and be extended horizontally to at least 5 feet beyond edge of the exterior wall;

• be placed with geofabric over the excavated subgrade soils;

• be backfilled with compacted CLAYS of PIs greater than 25; and

• be sloped away from the building at a slope of not less than 6 inches vertical fall in first 10 feet.

CORPORATE OFFICE • OKLAHOMA CITY

3400 N Lincoln Blvd • Oklahoma City, OK 73105-5493

(405) 528-0541 • (800) 725-0541 • (405) 528-0559 FAX

902 Trails West Loop

Enid, OK 73703-6336

(580) 237-3130

(800) 725-3130

(580) 237-3211 FAX

202 SE "J" Ave Lawton, OK 73501-2481

(580) 353-0872

(800) 725-0872

(580) 353-1263 FAX

Burns & McDonnell Engineering Company, Inc.

Subsurface Exploration - Addendum- Clay Cap Recommendations Altus Air Force Base KC-46A FTU/ FTC Simulator Facility Phase 2, Altus, Oklahoma Standard Testing Project No. 5616-3908A1

This addendum report has been prepared in accordance with generally accepted geotechnical practice.

We appreciate the opportunity to assist on this project. Please call on us if we can be of further service.

Sincerely, Standard Testing & Engineering Company

Prepared By:

Reviewed By:

Dipendra Timalsina Sharma, E.I.

Ming-Cheng Peter Shau, P.E., D.GE

Staff Geotechnical Engineer Manager, Geotechnical Services

I certify my e-signature for the study entitled “Subsurface Exploration

- Addendum”

CA No. 77, Expiration 6/30/2017