Clay, Per your request, please find the following summary of a phone conversation between Jonathan McCulley (Halff) and Maxwell Zhang (Geotel) that occurred earlier today. Should you require additional information, please feel free to contact Jonathan or myself. Eric Eric S. Christiansen, P.E., SECB, LEED AP Senior Structural Engineer HALFF ASSOCIATES, INC. 1201 North Bowser Road Richardson, Texas 75081 Phone 214-346-6284 Fax 214-739-0095 Cell 972-955-2996 www.halff.com From: McCulley, Jonathan Sent: Friday, January 07, 2011 5:25 PM To: Christiansen, Eric Subject: Conversation with Maxwell Eric, I called Maxwell at Geotel this afternoon (January 7, 2011) per the request of Nick Jacob. Nick informed me that he had attempted talking with Maxwell earlier in the day, but had difficulty understanding what Maxwell was saying. Nick specifically asked me to relay to Maxwell the geotechnical information Halff requires in order to check the structural capacity of the Ponte abutments with the backfill that is currently in place. When I talked with Maxwell, I indicated that Halff needs a recommendation on what lateral earth pressure we can use in our analysis based on the triaxial test performed by Kleinfelder on the existing backfill material. Maxwell made it sound as though this soil parameter would be simple to calculate, but he never told me what that lateral pressure would be. Further, he insisted that a global stability analysis must be run again. I asked him why global stability would even be an issue with these abutments seeing that they are supported on large, deep drilled shafts embedded into shale. He said something to the effect that if the shafts were not designed for lateral earth pressures, they could shear off. The shafts were indeed designed for lateral loads, but I did not push the issue of the global stability analysis any further. Maxwell also indicated that he was concerned that the backfill was not even a select fill, and expressed his confusion as to how obtaining an appropriate select fill was not accomplished and done so easily. He believes that if a select fill had actually been chosen correctly, there wouldn't be a problem with the test. I think everyone understands this point, but he kept pushing it. He finally gave me the impression over the phone that he was uncomfortable providing any geotechnical parameters or recommendations for the current backfill and seemed to think that Kleinfelder should be doing that work. I told him that if he does not want to provide the information Halff requires, he is free not to, but needs to take that up with UDR. That is where our conversation ended. Jonathan McCulley, P.E. Structural Engineer HALFF ASSOCIATES, INC. 1201 North Bowser Road Richardson, Texas 75081 Phone 214-217-6419 Fax 214-739-0095 www.halff.com