Index: Ringtoets/GrassCoverErosionOutwards/src/Ringtoets.GrassCoverErosionOutwards.Service/GrassCoverErosionOutwardsWaveConditionsCalculationActivity.cs
===================================================================
diff -u -r43b7b00322555d3a683e41c53ecda3fd135c5c37 -rf8c28b3b04cdabb62ea37772efcb1f4ebbbf2b9e
--- Ringtoets/GrassCoverErosionOutwards/src/Ringtoets.GrassCoverErosionOutwards.Service/GrassCoverErosionOutwardsWaveConditionsCalculationActivity.cs	(.../GrassCoverErosionOutwardsWaveConditionsCalculationActivity.cs)	(revision 43b7b00322555d3a683e41c53ecda3fd135c5c37)
+++ Ringtoets/GrassCoverErosionOutwards/src/Ringtoets.GrassCoverErosionOutwards.Service/GrassCoverErosionOutwardsWaveConditionsCalculationActivity.cs	(.../GrassCoverErosionOutwardsWaveConditionsCalculationActivity.cs)	(revision f8c28b3b04cdabb62ea37772efcb1f4ebbbf2b9e)
@@ -22,6 +22,7 @@
 using System;
 using Core.Common.Base.Service;
 using Ringtoets.Common.Data.AssessmentSection;
+using Ringtoets.Common.Data.Hydraulics;
 using Ringtoets.GrassCoverErosionOutwards.Data;
 using Ringtoets.HydraRing.Calculation.Activities;
 using RingtoetsCommonServiceResources = Ringtoets.Common.Service.Properties.Resources;
@@ -81,7 +82,9 @@
 
         protected override bool Validate()
         {
-            return GrassCoverErosionOutwardsWaveConditionsCalculationService.Validate(calculation, hlcdFilePath);
+            return GrassCoverErosionOutwardsWaveConditionsCalculationService.Validate(calculation,
+                                                                                      hlcdFilePath,
+                                                                                      assessmentSection.HydraulicBoundaryDatabase.EffectivePreprocessorDirectory());
         }
 
         protected override void PerformCalculation()