See https://sites.google.com/view/spatialaccuracy2020/home?authuser=0.

Nominations should be sent before January 31, 2020, to the Medal Committee chair, Gerard Heuvelink (gerard.heuvelink@wur.nl). The Medal Committee will render a decision within one month of the nomination deadline, in order to allow a recipient sufficient time to prepare to attend and present at the 2020 Spatial Accuracy symposium.

See https://www.spatial-accuracy.org/Eligibility for nomination instructions.