diff --git a/cdap-runtime-ext-dataproc/src/main/java/io/cdap/cdap/runtime/spi/runtimejob/DataprocJarUtil.java b/cdap-runtime-ext-dataproc/src/main/java/io/cdap/cdap/runtime/spi/runtimejob/DataprocJarUtil.java
index 25680b6aa388..0ef91a851578 100644
--- a/cdap-runtime-ext-dataproc/src/main/java/io/cdap/cdap/runtime/spi/runtimejob/DataprocJarUtil.java
+++ b/cdap-runtime-ext-dataproc/src/main/java/io/cdap/cdap/runtime/spi/runtimejob/DataprocJarUtil.java
@@ -55,11 +55,15 @@ public static synchronized LocalFile getTwillJar(LocationFactory locationFactory
       return getLocalFile(location, true);
     }
 
+    // scala gets bundled in the twill jar because it's a Kafka dependency,
+    // but Kafka is not used in Dataproc jobs at all. Exclude it to make sure it doesn't
+    // clash with the scala on the cluster.
+    // For example, Dataproc 1.5 uses scala-libary 2.12.10, which is incompatible with 2.12.15
     ApplicationBundler bundler = new ApplicationBundler(new ClassAcceptor() {
       @Override
       public boolean accept(String className, URL classUrl, URL classPathUrl) {
         return !className.startsWith("org.apache.hadoop") && !classPathUrl.toString()
-            .contains("spark-assembly");
+            .contains("spark-assembly") && !classPathUrl.toString().contains("scala-library");
       }
     });
     bundler.createBundle(location, ImmutableList.of(ApplicationMasterMain.class,
@@ -102,10 +106,10 @@ public boolean accept(String className, URL classUrl, URL classPathUrl) {
       }, DataprocJobMain.class.getName());
 
       // Add the logback-console.xml from resources
-      URL logbackURL = classLoader.getResource("logback-console.xml");
-      if (logbackURL != null) {
+      URL logbackUrl = classLoader.getResource("logback-console.xml");
+      if (logbackUrl != null) {
         jarOut.putNextEntry(new JarEntry("logback-console.xml"));
-        Resources.copy(logbackURL, jarOut);
+        Resources.copy(logbackUrl, jarOut);
       }
     }
     return getLocalFile(location, false);
diff --git a/cdap-runtime-ext-dataproc/src/test/java/io/cdap/cdap/runtime/spi/DataprocJarUtilTest.java b/cdap-runtime-ext-dataproc/src/test/java/io/cdap/cdap/runtime/spi/DataprocJarUtilTest.java
new file mode 100644
index 000000000000..88da296c03f4
--- /dev/null
+++ b/cdap-runtime-ext-dataproc/src/test/java/io/cdap/cdap/runtime/spi/DataprocJarUtilTest.java
@@ -0,0 +1,65 @@
+/*
+ *  Copyright © 2023 Cask Data, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ *  use this file except in compliance with the License. You may obtain a copy of
+ *  the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ *  License for the specific language governing permissions and limitations under
+ *  the License.
+ */
+
+package io.cdap.cdap.runtime.spi;
+
+import io.cdap.cdap.runtime.spi.runtimejob.DataprocJarUtil;
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.jar.JarEntry;
+import java.util.jar.JarInputStream;
+import java.util.stream.Collectors;
+import org.apache.twill.api.LocalFile;
+import org.apache.twill.filesystem.LocalLocationFactory;
+import org.apache.twill.filesystem.LocationFactory;
+import org.junit.Assert;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+public class DataprocJarUtilTest {
+
+  @ClassRule
+  public static final TemporaryFolder TMP_FOLDER = new TemporaryFolder();
+
+  @Test
+  public void testScalaLibraryNotPackaged() throws IOException {
+    LocationFactory locationFactory = new LocalLocationFactory(TMP_FOLDER.newFolder());
+    LocalFile localFile = DataprocJarUtil.getTwillJar(locationFactory);
+    File f = new File(localFile.getURI());
+
+    Set<String> scalaLibraries = new HashSet<>();
+    try (JarInputStream jarInput = new JarInputStream(Files.newInputStream(f.toPath()))) {
+      JarEntry entry;
+      while ((entry = jarInput.getNextJarEntry()) != null) {
+        // CDAP-20674: when this test was added, scala-library and scala-parser-combinators were
+        // both getting pulled into the twill.jar (with just scala-library causing problems)
+        // It is possible for this test to start failing in the future if twill changes.
+        // If that happens, it may be ok to add more scala libraries as expected libraries,
+        // but it should be a conscious, tested, decision
+        if (entry.getName().contains("scala") &&
+            !entry.getName().contains("scala-parser-combinators")) {
+          scalaLibraries.add(entry.getName());
+        }
+      }
+    }
+    Assert.assertTrue(String.format("Unexpected scala libraries in twill jar: %s",
+        scalaLibraries.stream().collect(Collectors.joining())), scalaLibraries.isEmpty());
+  }
+}