Norwegian to English Science Environment & Ecology environment/dredging

Graving, fylling, evt. mellomlagring av masser etc. skal utfoeres slik at ikke områdets stabilitet forstyrres og ras eller utglidninger utloeses.
No moral backsliding here - does anyone know whether an 'utglidning' is a landslip rather than a landslide, i.e. smaller, or is there another word?
Thanks,
Helen