diff --git a/src/backend/services/episode_evaluation_workflow_vontology_service.py b/src/backend/services/episode_evaluation_workflow_vontology_service.py
index cc4de43bc..9c01c54cf 100644
--- a/src/backend/services/episode_evaluation_workflow_vontology_service.py
+++ b/src/backend/services/episode_evaluation_workflow_vontology_service.py
@@ -242,15 +242,25 @@ def _ensure_episode_evaluation_event_bindings() -> dict[str, Any]:
     updated_count = 0
     bindings: list[dict[str, Any]] = []
 
-    for event_type in (
-        EVENT_TYPE_TURN_COMPLETION_GATE_FINALISED,
-        EVENT_TYPE_WORKFLOW_INSTANCE_TERMINAL,
-    ):
+    # JVNAUTOSCI-2507: the workflow.instance_terminal trigger is a recursive
+    # firehose — every workflow instance terminal (including episode_evaluation's
+    # OWN terminals) re-fires episode evaluation, so a single event self-sustains
+    # into an unbounded backlog (138k instances observed live, amplified by
+    # foreign workers on the shared cluster). It is bootstrapped DISABLED until a
+    # self-exclusion condition + throttling exist; the per-turn completion-gate
+    # trigger remains the supported entry point. replace_existing keeps the
+    # disabled state self-healing across restarts (otherwise bootstrap would
+    # re-enable it and the storm would return).
+    binding_enablement = {
+        EVENT_TYPE_TURN_COMPLETION_GATE_FINALISED: True,
+        EVENT_TYPE_WORKFLOW_INSTANCE_TERMINAL: False,
+    }
+    for event_type, binding_enabled in binding_enablement.items():
         binding, created, updated = manager.upsert_event_binding(
             event_type=event_type,
             workflow_id=EPISODE_EVALUATION_WORKFLOW_ID,
             input_mapping={},
-            enabled=True,
+            enabled=binding_enabled,
             actor=_MANAGED_BY,
             replace_existing=True,
         )
diff --git a/tests/backend/test_episode_evaluation_workflow_vontology_service.py b/tests/backend/test_episode_evaluation_workflow_vontology_service.py
index 0db40a77d..2e26e14c4 100644
--- a/tests/backend/test_episode_evaluation_workflow_vontology_service.py
+++ b/tests/backend/test_episode_evaluation_workflow_vontology_service.py
@@ -246,18 +246,33 @@ def test_bootstrap_materialises_episode_evaluation_workflow_family(
         enabled_only=True,
         limit=10,
     )
-    terminal_bindings = manager.list_event_bindings(
+    # JVNAUTOSCI-2507: the completion-gate trigger stays enabled, but the
+    # recursive workflow.instance_terminal trigger is bootstrapped DISABLED, so
+    # it must NOT appear among enabled bindings — while still existing (disabled)
+    # so it remains discoverable/re-enableable once properly gated.
+    enabled_terminal_bindings = manager.list_event_bindings(
         event_type=EVENT_TYPE_WORKFLOW_INSTANCE_TERMINAL,
         enabled_only=True,
         limit=10,
     )
+    all_terminal_bindings = manager.list_event_bindings(
+        event_type=EVENT_TYPE_WORKFLOW_INSTANCE_TERMINAL,
+        limit=10,
+    )
     assert any(
         binding.workflow_id == EPISODE_EVALUATION_WORKFLOW_ID for binding in turn_bindings
     )
-    assert any(
+    assert not any(
         binding.workflow_id == EPISODE_EVALUATION_WORKFLOW_ID
-        for binding in terminal_bindings
+        for binding in enabled_terminal_bindings
     )
+    episode_terminal_bindings = [
+        binding
+        for binding in all_terminal_bindings
+        if binding.workflow_id == EPISODE_EVALUATION_WORKFLOW_ID
+    ]
+    assert episode_terminal_bindings
+    assert episode_terminal_bindings[0].enabled is False
 
     for predicate_id in _WORKFLOW_EXPERIENCE_GUIDANCE_PREDICATES:
         doc = concept_service.get_concept_by_concept_id(predicate_id)