http://www.dailytech.com/article.aspx?newsid=18683
"Gayl suggests using the GBU-43 MOAB — known as the “Massive Ordinance Air Burst” or “Mother of All Bombs” — which has been "proven, safe and ‘green", according to Gayl. If a MOAB is unavailable, Gayl says a Vietnam-era Daisy Cutter would also do handsomely."