Index: Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionMerger.cs
===================================================================
diff -u -raa69c30a42cc90d74f4f219134a5af877dc4e857 -r7e75faf99817c4ce25763185811cba24c19bef67
--- Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionMerger.cs	(.../AssessmentSectionMerger.cs)	(revision aa69c30a42cc90d74f4f219134a5af877dc4e857)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionMerger.cs	(.../AssessmentSectionMerger.cs)	(revision 7e75faf99817c4ce25763185811cba24c19bef67)
@@ -23,7 +23,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using log4net;
-using Ringtoets.Common.Data.FailureMechanism;
 using Ringtoets.Integration.Data;
 using Ringtoets.Integration.Data.Merge;
 using Ringtoets.Integration.Forms.Merge;
Index: Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionProvider.cs
===================================================================
diff -u -r7fef5ada51843b4bfd4cfe03d511fb86051c78a7 -r7e75faf99817c4ce25763185811cba24c19bef67
--- Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionProvider.cs	(.../AssessmentSectionProvider.cs)	(revision 7fef5ada51843b4bfd4cfe03d511fb86051c78a7)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Merge/AssessmentSectionProvider.cs	(.../AssessmentSectionProvider.cs)	(revision 7e75faf99817c4ce25763185811cba24c19bef67)
@@ -36,7 +36,6 @@
     public class AssessmentSectionProvider : IAssessmentSectionProvider
     {
         private readonly IWin32Window viewParent;
-        private readonly AssessmentSectionsOwner assessmentSectionsOwner;
 
         /// <summary>
         /// Initializes a new instance of <see cref="AssessmentSectionProvider"/>.
@@ -52,7 +51,6 @@
             }
 
             this.viewParent = viewParent;
-            assessmentSectionsOwner = new AssessmentSectionsOwner();
         }
 
         public IEnumerable<AssessmentSection> GetAssessmentSections(string filePath)
@@ -62,6 +60,8 @@
                 throw new ArgumentNullException(nameof(filePath));
             }
 
+            var assessmentSectionsOwner = new AssessmentSectionsOwner();
+
             ActivityProgressDialogRunner.Run(viewParent,
                                              LoadAssessmentSectionsActivityFactory.CreateLoadAssessmentSectionsActivity(
                                                  assessmentSectionsOwner, new LoadAssessmentSectionService(new StorageSqLite()),
Index: Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Merge/AssessmentSectionProviderTest.cs
===================================================================
diff -u -r3d87eac80e424a1690895a0375cdd66230081079 -r7e75faf99817c4ce25763185811cba24c19bef67
--- Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Merge/AssessmentSectionProviderTest.cs	(.../AssessmentSectionProviderTest.cs)	(revision 3d87eac80e424a1690895a0375cdd66230081079)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Merge/AssessmentSectionProviderTest.cs	(.../AssessmentSectionProviderTest.cs)	(revision 7e75faf99817c4ce25763185811cba24c19bef67)
@@ -130,5 +130,39 @@
             Assert.AreEqual(1, assessmentSections.Count());
             mocks.VerifyAll();
         }
+
+        [Test]
+        public void GivenGetAssessmentSectionsAlreadyCalled_WhenCallingAgainWithInvalidFilePath_ThenThrowsAssessmentSectionProviderException()
+        {
+            // Given
+            var mocks = new MockRepository();
+            var viewParent = mocks.Stub<IWin32Window>();
+            mocks.ReplayAll();
+
+            var provider = new AssessmentSectionProvider(viewParent);
+            string filePath = Path.Combine(testDataPath, "project.rtd");
+
+            DialogBoxHandler = (name, wnd) =>
+            {
+                // Expect an activity dialog which is automatically closed
+            };
+
+            IEnumerable<AssessmentSection> assessmentSections = provider.GetAssessmentSections(filePath);
+
+            // Precondition
+            Assert.AreEqual(1, assessmentSections.Count());
+
+            DialogBoxHandler = (name, wnd) =>
+            {
+                // Expect an activity dialog which is automatically closed
+            };
+
+            // When
+            TestDelegate call = () => assessmentSections = provider.GetAssessmentSections("filePath");
+
+            // Then
+            Assert.Throws<AssessmentSectionProviderException>(call);
+            mocks.VerifyAll();
+        }
     }
 }
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