diff --git a/phreeqcpp/cvode.cpp b/phreeqcpp/cvode.cpp
index b6193ce2..5214c750 100644
--- a/phreeqcpp/cvode.cpp
+++ b/phreeqcpp/cvode.cpp
@@ -3589,7 +3589,8 @@ CVsldet(CVodeMem cv_mem)
 	realtype rr, rrcut, vrrtol, vrrt2, sqtol, rrtol;
 	realtype smink, smaxk, sumrat, sumrsq, vmin, vmax, drrmax, adrr;
 	realtype /*small_cvode,*/ tem, sqmax, saqk, qp, s, sqmaxk, saqj, sqmin;
-	realtype rsa, rsb, rsc, rsd, rse, rd1a, rd1b, rd1c, rd1d;
+	//realtype rsa, rsb, rsc, rsd, rse, rd1a, rd1b, rd1c, rd1d;
+	realtype rsa, rsb, rsc, rsd, rse, rd1a, rd1b, rd1c;
 	//realtype rd2a, rd2b, rd2c, rd3a, rd3b, cest1, corr1;
 	realtype rd2a, rd2b, rd3a, cest1, corr1;
 	realtype ratp, ratm, qfac1, qfac2, bb, rrb;
@@ -3850,7 +3851,7 @@ CVsldet(CVodeMem cv_mem)
 		rd1a = rsa - rsb;
 		rd1b = rsb - rsc;
 		rd1c = rsc - rsd;
-		rd1d = rsd - rse;
+		//rd1d = rsd - rse;
 		rd2a = rd1a - rd1b;
 		rd2b = rd1b - rd1c;
 		//rd2c = rd1c - rd1d;