Additional Reference Material & Links: 

AC 150/5300-13 Paragraph 503
Line of Sight Standards "the following standards provide the minimum line of sight: 
a. Along Individual Runways  An acceptable runway profile permits any two points five feet (1.5m) above the runway centerline to be mutually visible for the entire runway length"

December 7, 2005  - "Ronnie Fitzgerald, an engineer with the state aeronautics division, said the video proved there is a problem with the runway." See the Video

December 14, 2005 - The FAA responds to a written request from a local pilot and states " the FAA has recommended that the portion of the runway behind the proposed threshold relocation be marked as unusable for runway or taxi operations"

December 16, 2005 - The Tennessee Aeronautical Division provided a written statement "working with the airport’s consultant, verified the validity of your line of sight concern . We have also determined that the completion of the parallel taxiway will not completely alleviate this problem". They further state that  "upon further discussions with the FAA, we have decided to simply recommend the temporary closure of the new portion of the taxiwayuntil we determine the ultimate solution to the line of sight problem ."

March 23, 2006 - "Were going to fix that - State takes responsibility for airport"