Detail
Type Ab. - Heidkrug is a Abbau (Surface Mine).
Kr Verden Aller - The Kreis for Heidkrug is Verden Aller. A Kreis is a government district (similar to a U.S. county).
See Holtum - A See notation means the entry is dependent on another entry. In this case, Heidkrug is dependent on Holtum, which should be consulted for additional information.