diff --git a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/MuonPrepRawDataProviderTools/MuonPrepRawDataCollectionProviderTool.h b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/MuonPrepRawDataProviderTools/MuonPrepRawDataCollectionProviderTool.h
index 608331b3010f01c839ada449aa49f161a6c14e8f..e1a24e197eec088a2e019cf22151d5fdcc3e005a 100644
--- a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/MuonPrepRawDataProviderTools/MuonPrepRawDataCollectionProviderTool.h
+++ b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/MuonPrepRawDataProviderTools/MuonPrepRawDataCollectionProviderTool.h
@@ -40,12 +40,12 @@ namespace Muon {
     static const InterfaceID& interfaceID() { return IID_MuonPrepRawDataCollectionProviderTool; }
 
     /** access data in layer */
-    bool getLayerData( int sector, MuonStationIndex::DetectorRegionIndex regionIndex, MuonStationIndex::LayerIndex layerIndex, MuonLayerPrepRawData& layerPrepRawData );
+    bool getLayerData( int sector, MuonStationIndex::DetectorRegionIndex regionIndex, MuonStationIndex::LayerIndex layerIndex, MuonLayerPrepRawData& layerPrepRawData ) const;
 
     /** access data in layer for a given technology */
     template<class COL>
     bool getLayerData( int sector, MuonStationIndex::TechnologyIndex technology, MuonStationIndex::DetectorRegionIndex regionIndex, 
-                       MuonStationIndex::LayerIndex layerIndex, std::vector<const COL*>& output ) {
+                       MuonStationIndex::LayerIndex layerIndex, std::vector<const COL*>& output ) const {
 
       // get technologies in the given layer
       unsigned int sectorLayerHash = MuonStationIndex::sectorLayerHash( regionIndex, layerIndex );
diff --git a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.cxx b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.cxx
index e130249a787ae06970a367bbc1f5abfbb7c2d69a..1e29ba7fc1c10a912fb86a0b3ecc7911d1c3af66 100644
--- a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.cxx
+++ b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.cxx
@@ -19,7 +19,7 @@ namespace Muon {
     m_idHelper("Muon::MuonIdHelperTool/MuonIdHelperTool"),
     m_mdtCreator("Muon::MdtDriftCircleOnTrackCreator/MdtDriftCircleOnTrackCreator"),
     m_clusterCreator("Muon::MuonClusterOnTrackCreator/MuonClusterOnTrackCreator"),
-    m_recoValidationTool("Muon::MuonRecoValidationTool/MuonRecoValidationTool"),
+    m_recoValidationTool(""), // ("Muon::MuonRecoValidationTool/MuonRecoValidationTool"),
     // m_pullCalculator("Trk::ResidualPullCalculator/ResidualPullCalculator"),    
     m_distanceToTubeCut(1000.),
     m_secondCoordinateCut(1500.)
diff --git a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.h b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.h
index 5ee86f1ee55979c5b81a053ac09aa53e2e6642d6..d508869db1de509089ae841147aef4ba64246d63 100644
--- a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.h
+++ b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPRDSelectionTool.h
@@ -93,7 +93,7 @@ namespace Muon {
     ToolHandle<MuonIdHelperTool>              m_idHelper; 
     ToolHandle<IMdtDriftCircleOnTrackCreator> m_mdtCreator; //<! pointer to mdt rio ontrack creator
     ToolHandle<IMuonClusterOnTrackCreator>    m_clusterCreator;  //<! pointer to muon cluster rio ontrack creator
-    ToolHandle<IMuonRecoValidationTool>       m_recoValidationTool;
+    mutable ToolHandle<IMuonRecoValidationTool>       m_recoValidationTool; //<! FIXME!
 
     /** cuts */
     double m_distanceToTubeCut;
diff --git a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPrepRawDataCollectionProviderTool.cxx b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPrepRawDataCollectionProviderTool.cxx
index 0d633a6ca38dbc1c678bdc6b15ff8a3ef6b67e45..48837dfbe390f09981e8d7f2f842015131cc1f71 100644
--- a/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPrepRawDataCollectionProviderTool.cxx
+++ b/MuonSpectrometer/MuonCnv/MuonPrepRawDataProviderTools/src/MuonPrepRawDataCollectionProviderTool.cxx
@@ -42,7 +42,7 @@ namespace Muon {
   }
 
   bool MuonPrepRawDataCollectionProviderTool::getLayerData( int sector, MuonStationIndex::DetectorRegionIndex regionIndex, 
-                                                            MuonStationIndex::LayerIndex layerIndex, MuonLayerPrepRawData& layerPrepRawData ) {
+                                                            MuonStationIndex::LayerIndex layerIndex, MuonLayerPrepRawData& layerPrepRawData ) const {
     
     // get technologies in the given layer
     MuonStationIndex::StIndex stIndex = MuonStationIndex::toStationIndex( regionIndex, layerIndex );