diff --git a/Exec/science/flame_wave/ci-benchmarks/job_info_params.txt b/Exec/science/flame_wave/ci-benchmarks/job_info_params.txt
index 127b5bcb64..252b98a482 100644
--- a/Exec/science/flame_wave/ci-benchmarks/job_info_params.txt
+++ b/Exec/science/flame_wave/ci-benchmarks/job_info_params.txt
@@ -54,9 +54,9 @@
     castro.plm_limiter = 2
     castro.hybrid_riemann = 0
     castro.riemann_solver = 0
-    castro.cg_maxiter = 12
-    castro.cg_tol = 1e-05
-    castro.cg_blend = 2
+    castro.riemann_shock_maxiter = 12
+    castro.riemann_pstar_tol = 1e-05
+    castro.riemann_cg_blend = 2
     castro.use_flattening = 1
     castro.transverse_use_eos = 0
     castro.transverse_reset_density = 1
diff --git a/Exec/science/wdmerger/inputs b/Exec/science/wdmerger/inputs
index 5def509a0d..f9b22104b2 100644
--- a/Exec/science/wdmerger/inputs
+++ b/Exec/science/wdmerger/inputs
@@ -188,7 +188,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when 
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor b/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor
index 2ff2712602..a7028d1544 100644
--- a/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor
+++ b/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor
@@ -200,7 +200,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when 
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_simp_sdc b/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_simp_sdc
index db97ad3dac..6316753695 100644
--- a/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_simp_sdc
+++ b/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_simp_sdc
@@ -206,7 +206,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_strang b/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_strang
index a57a028d0d..b56d9ba2a5 100644
--- a/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_strang
+++ b/Exec/science/wdmerger/tests/he_double_det/inputs_pakmor_strang
@@ -206,7 +206,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Exec/science/wdmerger/tests/he_double_det/inputs_scaling b/Exec/science/wdmerger/tests/he_double_det/inputs_scaling
index 03c95c1636..990c81fd2a 100644
--- a/Exec/science/wdmerger/tests/he_double_det/inputs_scaling
+++ b/Exec/science/wdmerger/tests/he_double_det/inputs_scaling
@@ -203,7 +203,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when 
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Exec/science/wdmerger/tests/wdmerger_collision/inputs_2d_collision b/Exec/science/wdmerger/tests/wdmerger_collision/inputs_2d_collision
index 8a2bca0293..60a7db22d6 100644
--- a/Exec/science/wdmerger/tests/wdmerger_collision/inputs_2d_collision
+++ b/Exec/science/wdmerger/tests/wdmerger_collision/inputs_2d_collision
@@ -153,7 +153,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when 
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Exec/science/wdmerger/tests/wdmerger_collision_1D/inputs b/Exec/science/wdmerger/tests/wdmerger_collision_1D/inputs
index 6dcabf249c..9f40085682 100644
--- a/Exec/science/wdmerger/tests/wdmerger_collision_1D/inputs
+++ b/Exec/science/wdmerger/tests/wdmerger_collision_1D/inputs
@@ -142,7 +142,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when 
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Exec/science/wdmerger/tests/wdmerger_retry/inputs_test_wdmerger_retry b/Exec/science/wdmerger/tests/wdmerger_retry/inputs_test_wdmerger_retry
index 0d63ab606c..a6eef171b3 100644
--- a/Exec/science/wdmerger/tests/wdmerger_retry/inputs_test_wdmerger_retry
+++ b/Exec/science/wdmerger/tests/wdmerger_retry/inputs_test_wdmerger_retry
@@ -133,7 +133,7 @@ castro.riemann_solver = 0
 
 # For the CG Riemann solver, we need to tell the solver not to quit when 
 # the iterations don't converge, but instead to do additional bisection iteration.
-castro.cg_blend = 2
+castro.riemann_cg_blend = 2
 
 # Use a lagged predictor estimate of the source terms in the hydro
 castro.source_term_predictor = 1
diff --git a/Source/driver/Castro.cpp b/Source/driver/Castro.cpp
index d79f4d4935..f478f8402d 100644
--- a/Source/driver/Castro.cpp
+++ b/Source/driver/Castro.cpp
@@ -392,12 +392,12 @@ Castro::read_params ()
 #endif
 
     if (riemann_solver == 1) {
-        if (cg_maxiter > HISTORY_SIZE) {
-            amrex::Error("error in riemanncg: cg_maxiter > HISTORY_SIZE");
+        if (riemann_shock_maxiter > HISTORY_SIZE) {
+            amrex::Error("riemann_shock_maxiter > HISTORY_SIZE");
         }
 
-        if (cg_blend == 2 && cg_maxiter < 5) {
-            amrex::Error("Error: need cg_maxiter >= 5 to do a bisection search on secant iteration failure.");
+        if (riemann_cg_blend == 2 && riemann_shock_maxiter < 5) {
+            amrex::Error("Error: need riemann_shock_maxiter >= 5 to do a bisection search on secant iteration failure.");
         }
     }
 #endif
diff --git a/Source/driver/_cpp_parameters b/Source/driver/_cpp_parameters
index a342478def..f5cdc29bd3 100644
--- a/Source/driver/_cpp_parameters
+++ b/Source/driver/_cpp_parameters
@@ -114,20 +114,19 @@ hybrid_riemann               bool           0
 # 2: HLLC
 riemann_solver               int           0
 
-# for the Colella \& Glaz Riemann solver, the maximum number
-# of iterations to take when solving for the star state
-cg_maxiter                   int          12
+# maximum number of iterations to used in the Riemann solver
+# when solving for the star state
+riemann_shock_maxiter                   int          12
 
-# for the Colella \& Glaz Riemann solver, the tolerance to
-# demand in finding the star state
-cg_tol                       Real          1.0e-5
+# tolerance to use when finding the star stat
+riemann_pstar_tol                       Real          1.0e-5
 
 # for the Colella \& Glaz Riemann solver, what to do if
 # we do not converge to a solution for the star state.
 # 0 = do nothing; print iterations and exit
 # 1 = revert to the original guess for p-star
-# 2 = do a bisection search for another 2 * cg_maxiter iterations.
-cg_blend                     int           2
+# 2 = do a bisection search for another 2 * riemann_shock_maxiter iterations.
+riemann_cg_blend                     int           2
 
 # flatten the reconstructed profiles around shocks to prevent them
 # from becoming too thin
diff --git a/Source/hydro/riemann_2shock_solvers.H b/Source/hydro/riemann_2shock_solvers.H
index 208e9878e0..f81b495f29 100644
--- a/Source/hydro/riemann_2shock_solvers.H
+++ b/Source/hydro/riemann_2shock_solvers.H
@@ -58,7 +58,7 @@ namespace TwoShock {
                     const amrex::Real ur, const amrex::Real pr, const amrex::Real taur,
                     const amrex::Real gamer, const amrex::Real clsqr,
                     const amrex::Real gdot, const amrex::Real gmin, const amrex::Real gmax,
-                    const int lcg_maxiter, const amrex::Real lcg_tol,
+                    const int lriemann_shock_maxiter, const amrex::Real lriemann_pstar_tol,
                     amrex::Real& pstar, amrex::Real& gamstar,
                     bool& converged, amrex::GpuArray<amrex::Real, PSTAR_BISECT_FACTOR*HISTORY_SIZE>& pstar_hist_extra) {
 
@@ -106,7 +106,7 @@ namespace TwoShock {
       converged = false;
       amrex::Real pstar_c = 0.0;
 
-      for (int iter = 0; iter < PSTAR_BISECT_FACTOR*lcg_maxiter; iter++) {
+      for (int iter = 0; iter < PSTAR_BISECT_FACTOR * lriemann_shock_maxiter; iter++) {
 
         pstar_c = 0.5_rt * (pstar_lo + pstar_hi);
         pstar_hist_extra[iter] = pstar_c;
@@ -125,7 +125,7 @@ namespace TwoShock {
 
         amrex::Real f_c = ustar_l - ustar_r;
 
-        if ( 0.5_rt * std::abs(pstar_lo - pstar_hi) < lcg_tol * pstar_c ) {
+        if ( 0.5_rt * std::abs(pstar_lo - pstar_hi) < lriemann_pstar_tol * pstar_c ) {
           converged = true;
           break;
         }
@@ -239,7 +239,7 @@ namespace TwoShock {
       bool converged = false;
 
       int iter = 0;
-      while ((iter < cg_maxiter && !converged) || iter < 2) {
+      while ((iter < riemann_shock_maxiter && !converged) || iter < 2) {
 
           wsqge(ql.p, taul, gamel, gdot, gamstar,
                 gmin, gmax, clsql, pstar, wlsq);
@@ -281,7 +281,7 @@ namespace TwoShock {
           pstar = amrex::max(pstar, small_pres);
 
           amrex::Real err = std::abs(pstar - pstar_old);
-          if (err < cg_tol*pstar) {
+          if (err < riemann_pstar_tol * pstar) {
               converged = true;
           }
 
@@ -300,11 +300,11 @@ namespace TwoShock {
 
       if (!converged) {
 
-          if (cg_blend == 0) {
+          if (riemann_cg_blend == 0) {
 
     #ifndef AMREX_USE_GPU
               std::cout <<  "pstar history: " << std::endl;
-              for (int iter_l=0; iter_l < cg_maxiter; iter_l++) {
+              for (int iter_l=0; iter_l < riemann_shock_maxiter; iter_l++) {
                   std::cout << iter_l << " " << pstar_hist[iter_l] << std::endl;
               }
 
@@ -316,11 +316,11 @@ namespace TwoShock {
               amrex::Error("ERROR: non-convergence in the Riemann solver");
     #endif
 
-          } else if (cg_blend == 1) {
+          } else if (riemann_cg_blend == 1) {
 
               pstar = ql.p + ( (qr.p - ql.p) - wr * (qr.un - ql.un) ) * wl / (wl + wr);
 
-          } else if (cg_blend == 2) {
+          } else if (riemann_cg_blend == 2) {
 
               // we don't store the history if we are in CUDA, so
               // we can't do this
@@ -328,7 +328,7 @@ namespace TwoShock {
               // first try to find a reasonable bounds
               amrex::Real pstarl = 1.e200;
               amrex::Real pstaru = -1.e200;
-              for (int n = cg_maxiter-6; n < cg_maxiter; n++) {
+              for (int n = riemann_shock_maxiter-6; n < riemann_shock_maxiter; n++) {
                   pstarl = amrex::min(pstarl, pstar_hist[n]);
                   pstaru = amrex::max(pstaru, pstar_hist[n]);
               }
@@ -342,17 +342,17 @@ namespace TwoShock {
                               ql.un, ql.p, taul, gamel, clsql,
                               qr.un, qr.p, taur, gamer, clsqr,
                               gdot, gmin, gmax,
-                              cg_maxiter, cg_tol,
+                              riemann_shock_maxiter, riemann_pstar_tol,
                               pstar, gamstar, converged, pstar_hist_extra);
 
               if (!converged) {
 
                   std::cout << "pstar history: " << std::endl;
-                  for (int iter_l = 0; iter_l < cg_maxiter; iter_l++) {
+                  for (int iter_l = 0; iter_l < riemann_shock_maxiter; iter_l++) {
                       std::cout << iter_l << " " << pstar_hist[iter_l] << std::endl;
                   }
                   std::cout << "pstar extra history: " << std::endl;
-                  for (int iter_l = 0; iter_l < PSTAR_BISECT_FACTOR*cg_maxiter; iter_l++) {
+                  for (int iter_l = 0; iter_l < PSTAR_BISECT_FACTOR * riemann_shock_maxiter; iter_l++) {
                       std::cout << iter_l << " " << pstar_hist_extra[iter_l] << std::endl;
                   }
 
@@ -368,7 +368,7 @@ namespace TwoShock {
           } else {
 
     #ifndef AMREX_USE_GPU
-              amrex::Error("ERROR: unrecognized cg_blend option.");
+              amrex::Error("ERROR: unrecognized riemann_cg_blend option.");
     #endif
           }