1132 Bishop Street, Suite 1200

Honolulu, Hawaii 96813 Phone: (808) 524-3771 Fax: (808) 538-0445

12 May 2014

Helber Hastert & Fee Planners, Inc.

Pacific Guardian Center 733 Bishop Street, Suite 2590

Honolulu, Hawaii 96813

Attention: Mr. Tom Fee

President

Project: N62742-11-D-1800 Amendment No. 25, Red Hill Facility Update GWPP, GroundWater Model, Contaminant Transport Analysis, Phase 1, Joint Base Pearl HarborHickam, Oahu, Hawaii HDRHNL 2013035

Subject: Additional Monitoring Well Locations

In accordance with our agreement for Amendment 25 under Contract N62742-11-D-1800 we have been developing a plan and approach for update of the Ground Water Model and the Contaminant Transport Analysis for the Red Hill Fuel Facility area. We have engaged Mr. Kolja

Rotzoll and Mr. Robert Whittier in discussions for development of our plan and approach. Mr. Rotzoll developed the Ground Water Model for the Red Hill Fuel Facility area and conducted the previous analysis of ground water movement within the area. Mr. Whittier developed the Contaminant Transport Model for the Red Hill Fuel Facility area and conducted the previous analysis of contaminant transport within the area. Please note that our current focus is to provide information needed to respond to the letters from the State of Hawaii Department of Health to Navy Region Hawaii dated February 12, 2014 and February 26, 2014. These letters relate to the suspected fuel release reported in January 2014.

A series of meetings were held to discuss the data requirements for update of the Ground Water Model and the Contaminant Transport Analysis. It was concluded that additional monitoring wells, in addition to additional information from existing available monitoring well locations, would be essential for making the update a meaningful and more technically accurate representation of ground water movement and contaminant transport.

Attached is a map prepared by Mr. Rotzoll and Mr. Whittier identifying four locations for additional monitoring wells. The wells are numbered in order of priority of importance for the update of the ground water and contaminant transport models. Please note that Well 1 and Well 2 are generally considered essential for the update and of equal importance. The additional data obtained from Wells 1 and 2 would represent the minimum additional information needed to generate meaningful and more technically accurate results from the ground water and contaminant transport models.Helber Hastert & Fee Planners, Inc. 12 May 2014 Page 2

Well 3 and Well 4 would also provide very valuabl e information that would further enhance the models. However, a phased approach with review of data collected from Wells 1 and 2 would allow an opportunity to adjust the locations of Well 3 and Well 4 if determined to be beneficial to further improve the models.

Please note that additional future monitoring wells could further enhance the models and provide additional information that could be very beneficial for other studies related to the ground water resources underlying the Red Hill Fuel Facility. However, we are focusing providing information needed for the suspected release reported in January 2014.

Please do not hesitate to contact us if there are any questions. We look forward to continuing to work with you on this project.

Very truly yours,

HDR ENGINEERING, INC.

Francis T. Hino

Vice President

Attachment

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