Bilsch,

read your link again....well, here's a shortcut from the NTSB update

"The Operations group has found that four airplanes landed on runway 13 between the conclusion of snow-clearing operations at about 10:40 local time and the accident flight. It also determined that the airplane that landed three minutes before the accident flight was another Delta MD-88 airplane. The group has interviewed or obtained statements from all four flight crews. The group reviewed the Delta MD-88 pilot operational materials and found guidance to limit reverse engine pressure ratios (EPR) to 1.3 on contaminated runways."