diff --git a/java/src/org/broadinstitute/sting/gatk/walkers/annotator/ResidualQuality.java b/java/src/org/broadinstitute/sting/gatk/walkers/annotator/ResidualQuality.java
new file mode 100644
index 000000000..dbda3c2c6
--- /dev/null
+++ b/java/src/org/broadinstitute/sting/gatk/walkers/annotator/ResidualQuality.java
@@ -0,0 +1,88 @@
+package org.broadinstitute.sting.gatk.walkers.annotator;
+
+import org.broadinstitute.sting.utils.Pair;
+import org.broadinstitute.sting.utils.ReadBackedPileup;
+import org.broadinstitute.sting.utils.BaseUtils;
+import org.broadinstitute.sting.utils.genotype.Genotype;
+import org.broadinstitute.sting.gatk.contexts.ReferenceContext;
+
+import java.util.List;
+
+/**
+ * Created by IntelliJ IDEA.
+ * User: chartl
+ * Date: Nov 23, 2009
+ * Time: 1:39:39 PM
+ * To change this template use File | Settings | File Templates.
+ */
+public class ResidualQuality implements VariantAnnotation{
+    private static double EPSILON = Math.pow(10,-12);
+    public static String KEY_NAME = "ResidualQuality";
+
+    public boolean useZeroQualityReads() { return true; } // for robustness
+
+    public Pair<String,String> annotate( ReferenceContext ref, ReadBackedPileup p, List<Genotype> genotypes) {
+
+        Character snp = getSNPChar(ref, genotypes);
+        if ( snp == null ) {
+            return null;
+        }
+
+        Double logResidQual = getLogResidualQuality(p,ref.getBase(),snp);
+
+        if ( logResidQual == null ) {
+            return null;
+        }
+
+        return new Pair<String,String>(KEY_NAME, String.format("%f", logResidQual ));
+    }
+
+    private Double getLogResidualQuality( ReadBackedPileup p, char ref, char snp ) {
+        byte[] pbp = p.getBases();
+        byte[] quals = p.getQuals();
+        if ( pbp == null || quals == null ) {
+            return null;
+        }
+
+        int nSNP = 0;
+        int nRef = 0;
+        int pileupSize = pbp.length;
+        int sumOfQuals = 0;
+        for ( int i = 0; i < pileupSize; i ++ ) {
+            if ( BaseUtils.basesAreEqual( pbp[i], (byte) ref ) ) {
+                // ref site
+                nRef ++;
+            } else if ( BaseUtils.basesAreEqual ( pbp[i], ( byte ) snp ) ) {
+                // snp site
+                nSNP++;
+            } else {
+                // non-ref non-snp site, increase quality
+                sumOfQuals += quals[i];
+            }
+        }
+
+        // want to return sum of qualities times the proportion of non-SNP bases they account for (includes ref bases)
+        // taking the log gives    log(SQ) + log(non-ref non-snp bases) - log(non-snp bases)
+
+        return Math.log(sumOfQuals + EPSILON) + Math.log(pileupSize-nSNP-nRef+EPSILON) - Math.log(pileupSize-nSNP + EPSILON);
+    }
+
+    private Character getSNPChar( ReferenceContext ref, List<Genotype> genotypes ) {
+        try {
+            return getNonref( genotypes, ref.getBase() );
+        } catch ( IllegalStateException e ) {
+            return null;
+        }
+    }
+
+    private char getNonref(List<Genotype> genotypes, char ref) {
+        //logger.info(genotypes.size());
+        for ( Genotype g : genotypes ) {
+            //logger.info("Genotype: "+g.getBases()+" Ref from genotype: "+g.getReference()+" Ref from method: "+ref);
+            if ( g.isVariant(ref) ) {
+                return g.toVariation(ref).getAlternativeBaseForSNP();
+            }
+        }
+        throw new IllegalStateException("List of genotypes did not contain a variant.");
+    }
+}
diff --git a/java/test/org/broadinstitute/sting/gatk/walkers/annotator/VariantAnnotatorIntegrationTest.java b/java/test/org/broadinstitute/sting/gatk/walkers/annotator/VariantAnnotatorIntegrationTest.java
index 395566ea8..46fb9cccb 100755
--- a/java/test/org/broadinstitute/sting/gatk/walkers/annotator/VariantAnnotatorIntegrationTest.java
+++ b/java/test/org/broadinstitute/sting/gatk/walkers/annotator/VariantAnnotatorIntegrationTest.java
@@ -66,7 +66,7 @@ public class VariantAnnotatorIntegrationTest extends WalkerTest {
     public void testHasAnnotsAsking1() {
         WalkerTestSpec spec = new WalkerTestSpec(
                 baseTestString() + " -all -B variant,VCF,/humgen/gsa-scr1/GATK_Data/Validation_Data/vcfexample2.vcf -I /humgen/gsa-scr1/GATK_Data/Validation_Data/low_coverage_CEU.chr1.10k-11k.bam -L 1:10,020,000-10,021,000", 1,
-                Arrays.asList("ac80f5a5ab06037f938861effcceb66f"));
+                Arrays.asList("3b54731a929134410f167630ec434310"));
         executeTest("test file has annotations, asking for annotations, #1", spec);
     }
 
@@ -74,7 +74,7 @@ public class VariantAnnotatorIntegrationTest extends WalkerTest {
     public void testHasAnnotsAsking2() {
         WalkerTestSpec spec = new WalkerTestSpec(
                 baseTestString() + " -all -B variant,VCF,/humgen/gsa-scr1/GATK_Data/Validation_Data/vcfexample3.vcf -I /humgen/gsa-scr1/GATK_Data/Validation_Data/NA12878.1kg.p2.chr1_10mb_11_mb.SLX.bam -L 1:10,000,000-10,050,000", 1,
-                Arrays.asList("227f38b2f322780187eacd0c98ace3e6"));
+                Arrays.asList("c713d6d6cf922eab4150737f51f13abc"));
         executeTest("test file has annotations, asking for annotations, #2", spec);
     }
 
@@ -98,7 +98,7 @@ public class VariantAnnotatorIntegrationTest extends WalkerTest {
     public void testNoAnnotsAsking1() {
         WalkerTestSpec spec = new WalkerTestSpec(
                 baseTestString() + " -all -B variant,VCF,/humgen/gsa-scr1/GATK_Data/Validation_Data/vcfexample2empty.vcf -I /humgen/gsa-scr1/GATK_Data/Validation_Data/low_coverage_CEU.chr1.10k-11k.bam -L 1:10,020,000-10,021,000", 1,
-                Arrays.asList("cda6af61023e67ce8cc8d57cc6cd155b"));
+                Arrays.asList("0feb1dd8aae945ce5f05c1156acadd3c"));
         executeTest("test file doesn't have annotations, asking for annotations, #1", spec);
     }
 
@@ -106,7 +106,7 @@ public class VariantAnnotatorIntegrationTest extends WalkerTest {
     public void testNoAnnotsAsking2() {
         WalkerTestSpec spec = new WalkerTestSpec(
                 baseTestString() + " -all -B variant,VCF,/humgen/gsa-scr1/GATK_Data/Validation_Data/vcfexample3empty.vcf -I /humgen/gsa-scr1/GATK_Data/Validation_Data/NA12878.1kg.p2.chr1_10mb_11_mb.SLX.bam -L 1:10,000,000-10,050,000", 1,
-                Arrays.asList("1ed34e09afbc25e034597a97c7861077"));
+                Arrays.asList("b15b965af6d204cbb2926f59f68d987c"));
         executeTest("test file doesn't have annotations, asking for annotations, #2", spec);
     }