diff --git a/src/main/java/com/kamco/cd/kamcoback/common/inference/utils/GeoJsonValidator.java b/src/main/java/com/kamco/cd/kamcoback/common/inference/utils/GeoJsonValidator.java
index d0a750ba..e7a615c1 100644
--- a/src/main/java/com/kamco/cd/kamcoback/common/inference/utils/GeoJsonValidator.java
+++ b/src/main/java/com/kamco/cd/kamcoback/common/inference/utils/GeoJsonValidator.java
@@ -164,6 +164,9 @@ public class GeoJsonValidator {
     //   "geometry": {...}
     // }
     // ---------------------------------------------------------
+
+    int sampleIdx = 0;
+
     for (JsonNode feature : features) {
       JsonNode props = feature.get("properties");
 
@@ -172,6 +175,15 @@ public class GeoJsonValidator {
       String sceneId =
           (props != null && props.hasNonNull("scene_id")) ? props.get("scene_id").asText() : null;
 
+      if (sampleIdx < 5) {
+        log.info(
+            "[DEBUG] feature sample idx={}, propsExists={}, sceneId={}",
+            sampleIdx,
+            props != null,
+            sceneId);
+        sampleIdx++;
+      }
+
       // scene_id가 없거나 빈값이면 "정상적으로 도엽번호가 들어오지 않은 feature"로 카운트
       if (sceneId == null || sceneId.isBlank()) {
         nullIdCount++; // 도엽번호가 없으면 증가
@@ -179,7 +191,13 @@ public class GeoJsonValidator {
       }
 
       // foundUnique.add(sceneId)가 false면 "이미 같은 값이 있었다"는 뜻 => 중복
-      if (!foundUnique.add(sceneId)) {
+      boolean added = foundUnique.add(sceneId);
+
+      if (sampleIdx <= 5) {
+        log.info("[DEBUG] sceneId={}, added={}", sceneId, added);
+      }
+
+      if (!added) {
         duplicates.add(sceneId);
       }
     }