Index: Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Service/HeightStructuresCalculationActivity.cs
===================================================================
diff -u -r9cd1f99915772a8d9990c31e281b70dd663b4e2d -r57cf41dc262bf62fdf1dddc550884a2f79163d4e
--- Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Service/HeightStructuresCalculationActivity.cs	(.../HeightStructuresCalculationActivity.cs)	(revision 9cd1f99915772a8d9990c31e281b70dd663b4e2d)
+++ Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Service/HeightStructuresCalculationActivity.cs	(.../HeightStructuresCalculationActivity.cs)	(revision 57cf41dc262bf62fdf1dddc550884a2f79163d4e)
@@ -20,7 +20,6 @@
 // All rights reserved.
 
 using System;
-using Core.Common.Base.Service;
 using Ringtoets.Common.Data.AssessmentSection;
 using Ringtoets.Common.Data.Hydraulics;
 using Ringtoets.Common.Data.Structures;
@@ -31,9 +30,9 @@
 namespace Ringtoets.HeightStructures.Service
 {
     /// <summary>
-    /// <see cref="Activity"/> for running a height structures calculation.
+    /// <see cref="CalculatableActivity"/> for running a height structures calculation.
     /// </summary>
-    public class HeightStructuresCalculationActivity : HydraRingActivityBase
+    public class HeightStructuresCalculationActivity : CalculatableActivity
     {
         private readonly StructuresCalculation<HeightStructuresInput> calculation;
         private readonly string hydraulicBoundaryDatabaseFilePath;
@@ -56,14 +55,17 @@
             {
                 throw new ArgumentNullException(nameof(calculation));
             }
+
             if (hydraulicBoundaryDatabaseFilePath == null)
             {
                 throw new ArgumentNullException(nameof(hydraulicBoundaryDatabaseFilePath));
             }
+
             if (failureMechanism == null)
             {
                 throw new ArgumentNullException(nameof(failureMechanism));
             }
+
             if (assessmentSection == null)
             {
                 throw new ArgumentNullException(nameof(assessmentSection));