diff --git a/.github/workflows/Linux_options.yml b/.github/workflows/Linux_options.yml
index 853f803..f5ea5b5 100644
--- a/.github/workflows/Linux_options.yml
+++ b/.github/workflows/Linux_options.yml
@@ -105,6 +105,22 @@ jobs:
         make -j2
         make install
 
+    - name: checkout-g2c
+      uses: actions/checkout@v4
+      with:
+        repository: NOAA-EMC/NCEPLIBS-g2c
+        path: g2c
+        ref: develop
+  
+    - name: build-g2c
+      run: |
+        cd g2c
+        mkdir build
+        cd build
+        cmake .. -DCMAKE_INSTALL_PREFIX=~/g2c -DUSE_OpenJPEG=ON -DUSE_Jasper=OFF
+        make -j2
+        make install
+
     - name: checkout
       uses: actions/checkout@v2
       with: 
@@ -115,6 +131,7 @@ jobs:
         cd wgrib2
         mkdir b
         cd b
-        cmake ${{ matrix.config.options }} -DCMAKE_PREFIX_PATH="~/ip" ..
+        export CFLAGS='-I/home/runner/g2c/include'
+        cmake ${{ matrix.config.options }} -DCMAKE_PREFIX_PATH="~/ip;~/g2c" ..
         make VERBOSE=1
         ctest --verbose --output-on-failure --rerun-failed
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8bdc4ef..55dd0a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -121,7 +121,7 @@ endif()
 # Find required packages to use OpenJPEG
 message(STATUS "Checking if the user wants to use OpenJPEG...")
 if(USE_OPENJPEG)
-find_package(OpenJPEG REQUIRED)
+  find_package(g2c 1.9.0 CONFIG REQUIRED)
 endif()
 
 message(STATUS "Checking if the user want to use OpenMP...")
diff --git a/spack/package.py b/spack/package.py
index 7ddd52a..90bc92a 100644
--- a/spack/package.py
+++ b/spack/package.py
@@ -177,8 +177,8 @@ def url_for_version(self, version):
     depends_on("g2c", when="@develop +jasper")
     depends_on("zlib-api", when="@3.2: +png")
     depends_on("libpng", when="@3.2: +png")
-    depends_on("openjpeg", when="@3.2: +openjpeg")
-    
+    depends_on("openjpeg", when="@3.2:3.4 +openjpeg")
+    depends_on("g2c +openjpeg", when="@develop +openjpeg")
 
     @when("@:2 ^gmake@4.2:")
 
diff --git a/wgrib2/CMakeLists.txt b/wgrib2/CMakeLists.txt
index 6658cbf..878fe63 100644
--- a/wgrib2/CMakeLists.txt
+++ b/wgrib2/CMakeLists.txt
@@ -22,7 +22,7 @@ Alias.c Ave_test.c Ave_var.c Bbox.c bitstream.c Box_ave.c
 Check_pdt_size.c Checksum.c Cluster.c cname.c codetable_4_230.c
 CodeTable.c Code_Values.c Code_Values_JMA.c complex_pk.c Config.c
 copy.c crc32.c Cress_lola.c Csv.c Csv_long.c cubed_sphere2ll.c
-CubeFace2global.c Cyclic.c Data.c decenc_openjpeg.c dec_png_clone.c
+CubeFace2global.c Cyclic.c Data.c dec_png_clone.c
 Dump.c Earth.c Else.c End.c Endif.c Ensemble.c
 Ens_processing.c Ens_qc.c EOF.c Export_lonlat.c ExtName.c
 fatal_error.c Fcst_ave.c ffopen.c Fi.c File.c Fix_CFSv2_fcst.c
@@ -143,16 +143,11 @@ if(USE_AEC)
   target_link_libraries(wgrib2_exe PRIVATE ${LIBAEC_LIBRARIES})
 endif()
 
-if(USE_JASPER)
+if(USE_JASPER OR USE_OPENJPEG)
   target_link_libraries(obj_lib PUBLIC g2c::g2c)
   target_link_libraries(wgrib2_exe PRIVATE g2c::g2c)
 endif()
 
-if(USE_OPENJPEG)
-  include_directories(${OPENJPEG_INCLUDE_DIRS})
-  target_link_libraries(wgrib2_exe PRIVATE ${OPENJPEG_LIBRARIES})
-endif()
-
 target_link_libraries(wgrib2_exe PRIVATE obj_lib)
 # target_link_libraries(wgrib2_exe PRIVATE wgrib2_lib)
 
diff --git a/wgrib2/jpeg_pk.c b/wgrib2/jpeg_pk.c
index cc4661c..d2a6ec8 100644
--- a/wgrib2/jpeg_pk.c
+++ b/wgrib2/jpeg_pk.c
@@ -7,14 +7,11 @@
 #include "wgrib2.h"
 #include "fnlist.h"
 
-#ifdef USE_JASPER
-    #include "grib2.h"
-#endif
-
 /* 10/2024 Public Domain   Wesley Ebisuzaki */
 
 #if defined USE_JASPER  || defined USE_OPENJPEG
 
+    #include "grib2.h"
 /*
  *  writes out jpeg2000 compressed grib message
  */
@@ -31,9 +28,7 @@ int jpeg2000_grib_out(unsigned char **sec, float *data, unsigned int ndata,
     int i, k, nbits, nbytes;
     int ltype, ratio, retry;
     char *outjpc;
-#ifdef USE_JASPER
     unsigned char *cdata, *p;
-#endif
 
     /* required passed sections */
     sec0 = sec[0];
@@ -124,7 +119,6 @@ int jpeg2000_grib_out(unsigned char **sec, float *data, unsigned int ndata,
         nbytes = (nbits + 7) / 8;
         if (nbytes > 4) fatal_error_i("jpeg2000_grib_out number of bytes is %d > 4", nbytes);
 
-#ifdef USE_JASPER
         /* floats -> integers -> bytes */
 
         cdata = (unsigned char *) malloc(nbytes * (size_t) n_defined);
@@ -156,9 +150,6 @@ int jpeg2000_grib_out(unsigned char **sec, float *data, unsigned int ndata,
 	    }
         }
 
-//    jas_init();
-#endif
-
         ltype = 0;
         ratio = 1;
         retry = 0;
@@ -166,7 +157,6 @@ int jpeg2000_grib_out(unsigned char **sec, float *data, unsigned int ndata,
         jpclen = 4*n_defined+200;
         outjpc = (char *) malloc(jpclen);
 
-#ifdef USE_JASPER
         i = g2c_enc_jpeg2000(cdata,ix,iy,nbits,ltype,ratio,retry,outjpc,jpclen);
         // we try to catch following error: "error: too few guard bits (need at least x)"
         if (i == -3) {
@@ -174,10 +164,6 @@ int jpeg2000_grib_out(unsigned char **sec, float *data, unsigned int ndata,
             i = g2c_enc_jpeg2000(cdata,ix,iy,nbits,ltype,ratio,retry,outjpc,jpclen);
         }
 	free(cdata);
-#endif
-#ifdef USE_OPENJPEG
-        i = enc_jpeg2000_clone_float(data,ix,iy,nbits,ltype,ratio,retry,outjpc,jpclen);
-#endif
 
 	if (i <= 0) fatal_error_i("enc_jpeg error %d", i);
     }
diff --git a/wgrib2/unpk.c b/wgrib2/unpk.c
index eae0710..936a62a 100644
--- a/wgrib2/unpk.c
+++ b/wgrib2/unpk.c
@@ -12,7 +12,7 @@
 #include "wgrib2.h"
 #include "grb2.h"
 
-#ifdef USE_JASPER
+#if defined USE_JASPER  || defined USE_OPENJPEG
     #include "grib2.h"
 #endif
 
@@ -193,7 +193,6 @@ int unpk_grib(unsigned char **sec, float *data) {
 
 	// decode jpeg2000
 
-#ifdef USE_JASPER
     ifld = (int *) malloc(ndata * sizeof(int));
 	if (ifld == 0) fatal_error("unpk: memory allocation error","");
 	err = g2c_dec_jpeg2000((char *) sec[7]+5, (size_t) GB2_Sec7_size(sec)-5, ifld);
@@ -214,32 +213,6 @@ int unpk_grib(unsigned char **sec, float *data) {
 	}
     free(ifld);
 	return 0;
-#endif
-#ifdef USE_OPENJPEG
-        ifld = (int *) malloc(ndata * sizeof(int));
-	if (ifld == 0) fatal_error("unpk: memory allocation error","");
-	err = dec_jpeg2000_clone((char *) sec[7]+5, (int) GB2_Sec7_size(sec)-5, ifld);
-	if (err != 0) fatal_error_i("dec_jpeg2000, error %d",err);
-
-        if (bitmap_flag == 255) {
-#pragma omp parallel for private(ii)
-	    for (ii = 0; ii < ndata; ii++) {
-		data[ii] = ((ifld[ii]*bin_scale)+reference)*dec_scale;
-	    }
-	}
-        else if (bitmap_flag == 0 || bitmap_flag == 254) {
-            mask_pointer = sec[6] + 6;
-            mask = 0;
-	    kk = 0;
-            for (ii = 0; ii < ndata; ii++) {
-                if ((ii & 7) == 0) mask = *mask_pointer++;
-                data[ii] = (mask & 128) ? ((ifld[kk++]*bin_scale)+reference)*dec_scale : UNDEFINED;
-                mask <<= 1;
-            }
-	}
-	free(ifld);
-	return 0;
-#endif
     }
 #endif
 
diff --git a/wgrib2/wgrib2.h b/wgrib2/wgrib2.h
index 95005b1..7deb9d0 100644
--- a/wgrib2/wgrib2.h
+++ b/wgrib2/wgrib2.h
@@ -503,11 +503,6 @@ int scaling(unsigned char **sec, double *base, int *decimal, int *binary, int *n
 unsigned char *mk_bms(float *data, unsigned int *ndata);
 
 int dec_png_clone(unsigned char *pngbuf,int *width,int *height, unsigned char *cout, int *grib2_bit_depth, unsigned int ndata);
-#ifdef USE_OPENJPEG
-int dec_jpeg2000_clone(char *injpc, int bufsize, int *outfld);
-int enc_jpeg2000_clone_float(float *data, int width, int height, int nbits,
-                 int ltype, int ratio, int retry, char *outjpc, int jpclen);
-#endif
 int ieee_grib_out(unsigned char **sec, float *data, unsigned int ndata, struct seq_file *out);
 int jpeg_grib_out(unsigned char **sec, float *data, unsigned int ndata, 
     int nx, int ny, int use_scale, int dec_scale, int bin_scale, FILE *out);