diff --git a/java/src/org/broadinstitute/sting/oneoffprojects/walkers/CNV/GCcontentIntervalWalker.java b/java/src/org/broadinstitute/sting/oneoffprojects/walkers/CNV/GCcontentIntervalWalker.java
new file mode 100755
index 000000000..e1c5255b3
--- /dev/null
+++ b/java/src/org/broadinstitute/sting/oneoffprojects/walkers/CNV/GCcontentIntervalWalker.java
@@ -0,0 +1,151 @@
+/*
+ * Copyright (c) 2010, The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+package org.broadinstitute.sting.oneoffprojects.walkers.CNV;
+
+import org.broad.tribble.util.variantcontext.Genotype;
+import org.broad.tribble.util.variantcontext.VariantContext;
+import org.broadinstitute.sting.commandline.Argument;
+import org.broadinstitute.sting.commandline.Output;
+import org.broadinstitute.sting.gatk.contexts.AlignmentContext;
+import org.broadinstitute.sting.gatk.contexts.ReferenceContext;
+import org.broadinstitute.sting.gatk.filters.ZeroMappingQualityReadFilter;
+import org.broadinstitute.sting.gatk.refdata.RefMetaDataTracker;
+import org.broadinstitute.sting.gatk.refdata.ReferenceOrderedDatum;
+import org.broadinstitute.sting.gatk.refdata.utils.GATKFeature;
+import org.broadinstitute.sting.gatk.walkers.*;
+import org.broadinstitute.sting.utils.BaseUtils;
+import org.broadinstitute.sting.utils.GenomeLoc;
+import org.broadinstitute.sting.utils.exceptions.UserException;
+
+import java.io.PrintStream;
+import java.util.*;
+
+/**
+ * Walks along all variant ROD loci and verifies the phasing from the reads for user-defined pairs of sites.
+ */
+@Allows(value = {DataSource.REFERENCE})
+@Requires(value = {DataSource.REFERENCE})
+
+public class GCcontentIntervalWalker extends RodWalker<GCcounter, GCcounter> {
+    @Output
+    protected PrintStream out;
+
+    public boolean isReduceByInterval() {
+        return true;
+    }
+
+    public void initialize() {
+    }
+
+    public boolean generateExtendedEvents() {
+        return false;
+    }
+
+    public GCcounter reduceInit() {
+        return new GCcounter();
+    }
+
+    /**
+     * @param tracker the meta-data tracker
+     * @param ref     the reference base
+     * @param context the context for the given locus
+     * @return statistics of and list of all phased VariantContexts and their base pileup that have gone out of cacheWindow range.
+     */
+    public GCcounter map(RefMetaDataTracker tracker, ReferenceContext ref, AlignmentContext context) {
+        if (tracker == null)
+            return null;
+
+        List<GATKFeature> interval = tracker.getGATKFeatureMetaData("intervals", true);
+        if (interval.size() != 1) {
+            String error = "At " + ref.getLocus() + " : Must provide a track named 'intervals' with exactly ONE interval per locus in -L argument!";
+            if (interval.size() < 1)
+                throw new UserException(error);
+            else // interval.size() > 1
+                logger.warn(error);
+        }
+        GenomeLoc curInterval = interval.get(0).getLocation();
+
+        GCcounter counter = new GCcounter();
+        counter.calculateGCandAddIn(ref);
+        counter.loc = curInterval;
+
+        return counter;
+    }
+
+    public GCcounter reduce(GCcounter add, GCcounter runningCount) {
+        if (add == null)
+            add = new GCcounter();
+
+        return runningCount.addIn(add);
+    }
+
+    /**
+     * @param result the number of reads and VariantContexts seen.
+     */
+    public void onTraversalDone(GCcounter result) {
+        if (result.loc == null)
+            return;
+
+        double gcContent = (double) result.GCcount / result.totalCount;
+        out.println(result.loc + "\t" + gcContent + "\t" + result.loc.size());
+    }
+}
+
+class GCcounter {
+    public int totalCount;
+    public int GCcount;
+    public GenomeLoc loc;
+
+    public GCcounter() {
+        this.totalCount = 0;
+        this.GCcount = 0;
+        this.loc = null;
+    }
+
+    public GCcounter addIn(GCcounter other) {
+        this.totalCount += other.totalCount;
+        this.GCcount += other.GCcount;
+
+        if (other.loc != null && this.loc == null)
+            this.loc = other.loc;
+
+        return this;
+    }
+
+    public void calculateGCandAddIn(ReferenceContext ref) {
+        for (byte base : ref.getBases()) {
+            int baseIndex = BaseUtils.simpleBaseToBaseIndex(base);
+
+            boolean baseIsGC = (baseIndex == BaseUtils.gIndex || baseIndex == BaseUtils.cIndex);
+            boolean baseIsAT = (baseIndex == BaseUtils.aIndex || baseIndex == BaseUtils.tIndex);
+            if (baseIsGC || baseIsAT) {
+                totalCount++;
+                if (baseIsGC)
+                    GCcount++;
+            }
+        }
+    }
+}
+
diff --git a/scala/qscript/oneoffs/fromer/ReadDepthCNVanalysis.scala b/scala/qscript/oneoffs/fromer/ReadDepthCNVanalysis.scala
index 7b8e23484..3b8d64cb3 100644
--- a/scala/qscript/oneoffs/fromer/ReadDepthCNVanalysis.scala
+++ b/scala/qscript/oneoffs/fromer/ReadDepthCNVanalysis.scala
@@ -130,5 +130,8 @@ class ReadDepthCNVanalysis extends QScript {
       command += " " + input
     }
     def commandLine = command
+
+    // Since loading ALL of the output into the perl script can take significant memory:
+    this.memoryLimit = Some(9)
   }
 }
\ No newline at end of file