diff --git a/pom.xml b/pom.xml
index 0f7d8dc5..fc619f85 100644
--- a/pom.xml
+++ b/pom.xml
@@ -46,6 +46,12 @@
 <!--            <artifactId>spring-boot-configuration-processor</artifactId>-->
 <!--            <optional>true</optional>-->
 <!--        </dependency>-->
+        <!-- https://mvnrepository.com/artifact/commons-codec/commons-codec -->
+        <dependency>
+            <groupId>commons-codec</groupId>
+            <artifactId>commons-codec</artifactId>
+            <version>1.16.0</version>
+        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-security</artifactId>
@@ -64,6 +70,13 @@
             <artifactId>lombok</artifactId>
             <optional>true</optional>
         </dependency>
+        <!-- https://mvnrepository.com/artifact/junit/junit -->
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
diff --git a/src/main/java/au/org/aodn/esindexer/service/StacCollectionMapperServiceImpl.java b/src/main/java/au/org/aodn/esindexer/service/StacCollectionMapperServiceImpl.java
index ae7467ff..7436f910 100644
--- a/src/main/java/au/org/aodn/esindexer/service/StacCollectionMapperServiceImpl.java
+++ b/src/main/java/au/org/aodn/esindexer/service/StacCollectionMapperServiceImpl.java
@@ -5,6 +5,7 @@
 import au.org.aodn.esindexer.model.*;
 import au.org.aodn.esindexer.utils.BBoxUtils;
 import au.org.aodn.esindexer.utils.GeometryUtils;
+import au.org.aodn.esindexer.utils.StringUtil;
 import au.org.aodn.esindexer.utils.TemporalUtils;
 import au.org.aodn.metadata.iso19115_3_2018.*;
 import jakarta.xml.bind.JAXBElement;
@@ -257,11 +258,11 @@ String mapTitle(MDMetadataType source) {
                 // TODO: Null or empty check
                 AbstractCitationType ac = i.getCitation().getAbstractCitation().getValue();
                 if(ac instanceof CICitationType2 type2) {
-                    return type2.getTitle().getCharacterString().getValue().toString();
+                    return StringUtil.toUTF8String(type2.getTitle().getCharacterString().getValue().toString());
                 }
                 else if(ac instanceof CICitationType type1) {
                     // Backward compatible
-                    type1.getTitle().getCharacterString().getValue().toString();
+                    return StringUtil.toUTF8String(type1.getTitle().getCharacterString().getValue().toString());
                 }
             }
         }
@@ -273,10 +274,10 @@ protected List<Map<String, String>> mapThemesConcepts(MDKeywordsPropertyType des
         descriptiveKeyword.getMDKeywords().getKeyword().forEach(keyword -> {
             if (keyword != null) {
                 if (keyword.getCharacterString().getValue() instanceof AnchorType value) {
-                    keywords.add(Map.of("id", value.getValue(),
-                            "url", value.getHref()));
+                    keywords.add(Map.of("id", StringUtil.toUTF8String(value.getValue()),
+                            "url", StringUtil.toUTF8String(value.getHref())));
                 } else {
-                    keywords.add(Map.of("id", keyword.getCharacterString().getValue().toString()));
+                    keywords.add(Map.of("id", StringUtil.toUTF8String(keyword.getCharacterString().getValue().toString())));
                 }
             }
         });
@@ -290,12 +291,12 @@ protected String mapThemesTitle(MDKeywordsPropertyType descriptiveKeyword, Strin
             CharacterStringPropertyType titleString = thesaurusNameType2.getTitle();
             if (titleString != null && titleString.getCharacterString().getValue() instanceof  AnchorType value) {
                 if (value.getValue() != null) {
-                    return value.getValue();
+                    return StringUtil.toUTF8String(value.getValue());
                 } else {
                     return "";
                 }
             } else if (titleString != null && titleString.getCharacterString().getValue() instanceof String value) {
-                return value;
+                return StringUtil.toUTF8String(value);
             }
         }
         logger.debug("Unable to find themes' title for metadata record: " + uuid);
@@ -309,12 +310,12 @@ protected String mapThemesDescription(MDKeywordsPropertyType descriptiveKeyword,
             CharacterStringPropertyType titleString = thesaurusNameType2.getTitle();
             if (titleString != null && titleString.getCharacterString().getValue() instanceof  AnchorType value) {
                 if (value.getTitleAttribute() != null) {
-                    return value.getTitleAttribute();
+                    return StringUtil.toUTF8String(value.getTitleAttribute());
                 } else {
                     return "";
                 }
             } else if (titleString != null && titleString.getCharacterString().getValue() instanceof String value) {
-                return thesaurusNameType2.getAlternateTitle().stream().map(CharacterStringPropertyType::getCharacterString).map(JAXBElement::getValue).map(Object::toString).collect(Collectors.joining(", "));
+                return StringUtil.toUTF8String(thesaurusNameType2.getAlternateTitle().stream().map(CharacterStringPropertyType::getCharacterString).map(JAXBElement::getValue).map(Object::toString).collect(Collectors.joining(", ")));
             }
         }
         logger.debug("Unable to find themes' description for metadata record: " + uuid);
@@ -325,7 +326,7 @@ protected String mapThemesScheme(MDKeywordsPropertyType descriptiveKeyword, Stri
         AbstractCitationPropertyType abstractCitationPropertyType = descriptiveKeyword.getMDKeywords().getThesaurusName();
         if (abstractCitationPropertyType != null) {
             if (descriptiveKeyword.getMDKeywords().getType() != null) {
-                return descriptiveKeyword.getMDKeywords().getType().getMDKeywordTypeCode().getCodeListValue();
+                return StringUtil.toUTF8String(descriptiveKeyword.getMDKeywords().getType().getMDKeywordTypeCode().getCodeListValue());
             } else {
                 return "";
             }
@@ -370,7 +371,7 @@ List<LinkModel> mapLinks(MDMetadataType source) {
                                 linkModel.setType(Objects.equals(ciOnlineResource.getProtocol().getCharacterString().getValue().toString(), "WWW:LINK-1.0-http--link") ? "text/html" : "");
                                 linkModel.setHref(ciOnlineResource.getLinkage().getCharacterString().getValue().toString());
                                 linkModel.setRel(AppConstants.RECOMMENDED_LINK_REL_TYPE);
-                                linkModel.setTitle(ciOnlineResource.getName() != null ? ciOnlineResource.getName().getCharacterString().getValue().toString() : null);
+                                linkModel.setTitle(ciOnlineResource.getName() != null ? StringUtil.toUTF8String(ciOnlineResource.getName().getCharacterString().getValue().toString()) : null);
                                 results.add(linkModel);
                             }
                         }
@@ -393,7 +394,7 @@ String mapLicense(MDMetadataType source) {
                         legalConstraintsType.getOtherConstraints().forEach(otherConstraints -> {
                             for (String potentialKey : potentialKeys) {
                                 if (otherConstraints.getCharacterString() != null && otherConstraints.getCharacterString().getValue().toString().toLowerCase().contains(potentialKey)) {
-                                    licenses.add(otherConstraints.getCharacterString().getValue().toString());
+                                    licenses.add(StringUtil.toUTF8String(otherConstraints.getCharacterString().getValue().toString()));
                                 }
                             }
                         });
@@ -403,7 +404,7 @@ String mapLicense(MDMetadataType source) {
                                 legalConstraintsType.getReference().forEach(reference -> {
                                     if (reference.getAbstractCitation().getValue() instanceof CICitationType2 ciCitationType2) {
                                         if (ciCitationType2.getTitle() != null) {
-                                            licenses.add(ciCitationType2.getTitle().getCharacterString().getValue().toString());
+                                            licenses.add(StringUtil.toUTF8String(ciCitationType2.getTitle().getCharacterString().getValue().toString()));
                                         }
                                     }
                                 });
@@ -502,23 +503,23 @@ List<ContactsModel> mapContacts(MDMetadataType source) {
 
     protected String mapContactsRole(CIResponsibilityType2 ciResponsibility) {
         CodeListValueType roleCode = ciResponsibility.getRole().getCIRoleCode();
-        if (roleCode != null) { return roleCode.getCodeListValue(); } else { return ""; }
+        if (roleCode != null) { return StringUtil.toUTF8String(roleCode.getCodeListValue()); } else { return ""; }
     }
 
     protected String mapContactsOrganization(AbstractCIPartyPropertyType2 party) {
         String organisationString = party.getAbstractCIParty().getValue().getName().getCharacterString().getValue().toString();
-        if (organisationString != null) { return organisationString; } else { return ""; }
+        if (organisationString != null) { return StringUtil.toUTF8String(organisationString); } else { return ""; }
 
     }
 
     protected String mapContactsName(CIIndividualPropertyType2 individual) {
         CharacterStringPropertyType nameString = individual.getCIIndividual().getName();
-        if (nameString != null) { return individual.getCIIndividual().getName().getCharacterString().getValue().toString(); } else { return ""; }
+        if (nameString != null) { return StringUtil.toUTF8String(individual.getCIIndividual().getName().getCharacterString().getValue().toString()); } else { return ""; }
     }
 
     protected String mapContactsPosition(CIIndividualPropertyType2 individual) {
         CharacterStringPropertyType positionString = individual.getCIIndividual().getPositionName();
-        if (positionString != null) { return individual.getCIIndividual().getPositionName().getCharacterString().getValue().toString(); } else { return ""; }
+        if (positionString != null) { return StringUtil.toUTF8String(individual.getCIIndividual().getPositionName().getCharacterString().getValue().toString()); } else { return ""; }
     }
 
     protected Map<String, Object> mapContactsAddress(CIAddressPropertyType2 address) {
@@ -527,28 +528,28 @@ protected Map<String, Object> mapContactsAddress(CIAddressPropertyType2 address)
 
         address.getCIAddress().getDeliveryPoint().forEach(deliveryPoint -> {
             String deliveryPointString = deliveryPoint.getCharacterString().getValue().toString();
-            deliveryPoints.add(deliveryPointString != null ? deliveryPointString : "");
+            deliveryPoints.add(deliveryPointString != null ? StringUtil.toUTF8String(deliveryPointString) : "");
         });
         addressItem.put("deliveryPoint", deliveryPoints);
 
         CharacterStringPropertyType cityString = address.getCIAddress().getCity();
-        addressItem.put("city", cityString != null ? cityString.getCharacterString().getValue().toString() : "");
+        addressItem.put("city", cityString != null ? StringUtil.toUTF8String(cityString.getCharacterString().getValue().toString()) : "");
 
         CharacterStringPropertyType administrativeAreaString = address.getCIAddress().getAdministrativeArea();
-        addressItem.put("administrativeArea", administrativeAreaString != null ? administrativeAreaString.getCharacterString().getValue().toString() : "");
+        addressItem.put("administrativeArea", administrativeAreaString != null ? StringUtil.toUTF8String(administrativeAreaString.getCharacterString().getValue().toString()) : "");
 
         CharacterStringPropertyType postalCodeString = address.getCIAddress().getPostalCode();
-        addressItem.put("postalCode", postalCodeString != null ? postalCodeString.getCharacterString().getValue().toString() : "");
+        addressItem.put("postalCode", postalCodeString != null ? StringUtil.toUTF8String(postalCodeString.getCharacterString().getValue().toString()) : "");
 
         CharacterStringPropertyType countryString = address.getCIAddress().getCountry();
-        addressItem.put("country", countryString != null ? countryString.getCharacterString().getValue().toString() : "");
+        addressItem.put("country", countryString != null ? StringUtil.toUTF8String(countryString.getCharacterString().getValue().toString()) : "");
 
         return addressItem;
     }
 
     protected String mapContactsEmail(CharacterStringPropertyType electronicMailAddress) {
         if (electronicMailAddress != null) {
-            return electronicMailAddress.getCharacterString().getValue().toString();
+            return StringUtil.toUTF8String(electronicMailAddress.getCharacterString().getValue().toString());
         } else {
             return "";
         }
@@ -558,10 +559,10 @@ protected Map<String, String> mapContactsPhone(CITelephonePropertyType2 phone) {
         Map<String, String> phoneItem = new HashMap<>();
 
         CharacterStringPropertyType phoneString = phone.getCITelephone().getNumber();
-        phoneItem.put("value", phoneString != null ? phoneString.getCharacterString().getValue().toString() : "");
+        phoneItem.put("value", phoneString != null ? StringUtil.toUTF8String(phoneString.getCharacterString().getValue().toString()) : "");
 
         CodeListValueType phoneCode = phone.getCITelephone().getNumberType().getCITelephoneTypeCode();
-        phoneItem.put("roles", phoneCode != null ? phoneCode.getCodeListValue() : "");
+        phoneItem.put("roles", phoneCode != null ? StringUtil.toUTF8String(phoneCode.getCodeListValue()) : "");
 
         return phoneItem;
     }
@@ -570,13 +571,13 @@ protected Map<String, String> mapContactsOnlineResource(CIOnlineResourceProperty
         Map<String, String> onlineResourceItem = new HashMap<>();
 
         CharacterStringPropertyType linkString = onlineResource.getCIOnlineResource().getLinkage();
-        onlineResourceItem.put("href", linkString != null ? linkString.getCharacterString().getValue().toString() : "");
+        onlineResourceItem.put("href", linkString != null ? StringUtil.toUTF8String(linkString.getCharacterString().getValue().toString()) : "");
 
         CharacterStringPropertyType resourceNameString = onlineResource.getCIOnlineResource().getName();
-        onlineResourceItem.put("title", resourceNameString != null ? resourceNameString.getCharacterString().getValue().toString() : "");
+        onlineResourceItem.put("title", resourceNameString != null ? StringUtil.toUTF8String(resourceNameString.getCharacterString().getValue().toString()) : "");
 
         CharacterStringPropertyType linkTypeString = onlineResource.getCIOnlineResource().getProtocol();
-        onlineResourceItem.put("type", linkTypeString != null ? linkTypeString.getCharacterString().getValue().toString() : "");
+        onlineResourceItem.put("type", linkTypeString != null ? StringUtil.toUTF8String(linkTypeString.getCharacterString().getValue().toString()) : "");
 
         return onlineResourceItem;
     }
@@ -612,7 +613,7 @@ protected List<LanguageModel> mapLanguages(MDMetadataType source) {
 
     protected String mapLanguagesCode(MDDataIdentificationType i) {
         try {
-            return i.getDefaultLocale().getPTLocale().getValue().getLanguage().getLanguageCode().getCodeListValue();
+            return StringUtil.toUTF8String(i.getDefaultLocale().getPTLocale().getValue().getLanguage().getLanguageCode().getCodeListValue());
         } catch (NullPointerException e) {
             return null;
         }
@@ -646,8 +647,10 @@ protected <R> R createGeometryItems(
                                 .map(AbstractEXGeographicExtentPropertyType::getAbstractEXGeographicExtent)
                                 .filter(m -> m.getValue() instanceof EXBoundingPolygonType || m.getValue() instanceof EXGeographicBoundingBoxType)
                                 .map(m -> {
-                                    if (m.getValue() instanceof EXBoundingPolygonType) {
-                                        return (EXBoundingPolygonType) m.getValue();
+                                    if (m.getValue() instanceof EXBoundingPolygonType exBoundingPolygonType) {
+                                        if (!exBoundingPolygonType.getPolygon().isEmpty() && exBoundingPolygonType.getPolygon().get(0).getAbstractGeometry() != null) {
+                                            return exBoundingPolygonType;
+                                        }
                                     } else if (m.getValue() instanceof EXGeographicBoundingBoxType) {
                                         return (EXGeographicBoundingBoxType) m.getValue();
                                     }
diff --git a/src/main/java/au/org/aodn/esindexer/utils/StringUtil.java b/src/main/java/au/org/aodn/esindexer/utils/StringUtil.java
new file mode 100644
index 00000000..6ae19684
--- /dev/null
+++ b/src/main/java/au/org/aodn/esindexer/utils/StringUtil.java
@@ -0,0 +1,10 @@
+package au.org.aodn.esindexer.utils;
+
+import java.nio.charset.StandardCharsets;
+
+public class StringUtil {
+    // Static method to convert to UTF-8 String
+    public static String toUTF8String(String input) {
+        return new String(input.getBytes(StandardCharsets.UTF_8));
+    }
+}
diff --git a/src/test/StringUtilTest.java b/src/test/StringUtilTest.java
new file mode 100644
index 00000000..9e45f56b
--- /dev/null
+++ b/src/test/StringUtilTest.java
@@ -0,0 +1,27 @@
+import au.org.aodn.esindexer.utils.StringUtil;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class StringUtilTest {
+    @Test
+    public void testToUTF8String_withAsciiString() {
+        String asciiString = "Hello World";
+        String result = StringUtil.toUTF8String(asciiString);
+        assertEquals(asciiString, result, "The UTF-8 conversion of an ASCII string should not change the string");
+    }
+
+    @Test
+    public void testToUTF8String_withFrenchCharacters() {
+        String frenchString = "Bonjour le monde! Ça va?";
+        String result = StringUtil.toUTF8String(frenchString);
+        assertEquals(frenchString, result, "The UTF-8 conversion of a string with French characters should not change the string");
+    }
+
+    @Test
+    public void testToUTF8String_withDegreeSign() {
+        String stringWithDegreeSign = "Temperature: 25°C";
+        String result = StringUtil.toUTF8String(stringWithDegreeSign);
+        assertEquals(stringWithDegreeSign, result, "The UTF-8 conversion of a string with a degree sign should not change the string");
+    }
+}