diff --git a/CHANGELOG.md b/CHANGELOG.md
index 32984f5..d3d8d3b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 202409.04
+
+- Fixed wastewater sample writing bug.
+
 ## 202409.03
 
 - Better navigation and clarity in details panes.
diff --git a/src/submissions/backend/excel/writer.py b/src/submissions/backend/excel/writer.py
index 171927a..59ec47e 100644
--- a/src/submissions/backend/excel/writer.py
+++ b/src/submissions/backend/excel/writer.py
@@ -284,7 +284,8 @@ class SampleWriter(object):
         self.xl = xl
         self.sample_map = submission_type.construct_sample_map()['lookup_table']
         # self.samples = self.reconcile_map(sample_list)
-        samples = [item for item in self.reconcile_map(sample_list)]
+        # NOTE: exclude any samples without a submission rank.
+        samples = [item for item in self.reconcile_map(sample_list) if item['submission_rank'] > 0]
         self.samples = sorted(samples, key=lambda k: k['submission_rank'])
 
     def reconcile_map(self, sample_list: list) -> Generator[dict, None, None]:
diff --git a/src/submissions/frontend/widgets/submission_details.py b/src/submissions/frontend/widgets/submission_details.py
index 481a83c..69f06f4 100644
--- a/src/submissions/frontend/widgets/submission_details.py
+++ b/src/submissions/frontend/widgets/submission_details.py
@@ -79,6 +79,11 @@ class SubmissionDetails(QDialog):
             logger.debug(f"Updating export plate to: {self.export_plate}")
         else:
             self.btn.setEnabled(False)
+        if title == self.webview.history().items()[0].title():
+            logger.debug("Disabling back button")
+            self.back.setEnabled(False)
+        else:
+            self.back.setEnabled(True)
 
     @pyqtSlot(str)
     def sample_details(self, sample: str | BasicSample):