diff --git a/src/math/lp/nla_core.cpp b/src/math/lp/nla_core.cpp
index 3a3fb8b6e..16afe48ad 100644
--- a/src/math/lp/nla_core.cpp
+++ b/src/math/lp/nla_core.cpp
@@ -1331,21 +1331,6 @@ lbool core::test_check(
     return check(l);
 }
 
-lp::impq core::get_upper_bound_of_monomial(lpvar j) const {
-    SASSERT(false);
-}
-
-lp::impq core::get_lower_bound_of_monomial(lpvar j) const {
-    SASSERT(false);
-}
-
-bool core::monomial_has_lower_bound(lpvar j) const {
-    SASSERT(false);
-}
-
-bool core::monomial_has_upper_bound(lpvar j) const {
-    SASSERT(false);
-}
 } // end of nla
 
 
diff --git a/src/math/lp/nla_core.h b/src/math/lp/nla_core.h
index 06f4871b7..2c9f346c3 100644
--- a/src/math/lp/nla_core.h
+++ b/src/math/lp/nla_core.h
@@ -338,10 +338,6 @@ public:
     
     lbool  test_check(vector<lemma>& l);
     lpvar map_to_root(lpvar) const;
-    lp::impq get_upper_bound_of_monomial(lpvar j) const;
-    lp::impq get_lower_bound_of_monomial(lpvar j) const;
-    bool monomial_has_lower_bound(lpvar j) const;
-    bool monomial_has_upper_bound(lpvar j) const;
 };  // end of core
 
 struct pp_mon {
diff --git a/src/math/lp/nla_intervals.cpp b/src/math/lp/nla_intervals.cpp
index 14d683fb5..be3674c66 100644
--- a/src/math/lp/nla_intervals.cpp
+++ b/src/math/lp/nla_intervals.cpp
@@ -6,17 +6,17 @@
 namespace nla {
     
     bool intervals::check() {
-        m_region.reset();
-        for (auto const& m : c().emons()) {
-            if (!check(m)) {
-                return false;
-            }
-        }
-        for (auto const& t : m_solver.terms()) {
-            if (!check(*t)) {
-                return false;
-            }
-        }
+        // m_region.reset();
+        // for (auto const& m : m_core->emons()) {
+        //     if (!check(m)) {
+        //         return false;
+        //     }
+        // }
+        // for (auto const& t : m_solver.terms()) {
+        //     if (!check(*t)) {
+        //         return false;
+        //     }
+        // }
         return true;
     }
 
@@ -104,4 +104,27 @@ namespace nla {
         // convert term into factors for improved precision
         return true;
     }
+
+lp::impq intervals::get_upper_bound_of_monomial(lpvar j) const {
+    SASSERT(false);
+}
+
+lp::impq intervals::get_lower_bound_of_monomial(lpvar j) const {
+    SASSERT(false);
+}
+
+bool intervals::product_has_upper_bound(int sign, const svector<lpvar>&) const {
+    interval a;
+    
+}
+
+bool intervals::monomial_has_lower_bound(lpvar j) const {
+    const monomial& m = m_core->emons()[j];
+    return product_has_upper_bound(1, m.vars());
+}
+
+bool intervals::monomial_has_upper_bound(lpvar j) const {
+    const monomial& m = m_core->emons()[j];
+    return product_has_upper_bound(-1, m.vars());
+}
 }
diff --git a/src/math/lp/nla_intervals.h b/src/math/lp/nla_intervals.h
index 7213adba8..8602a2bfe 100644
--- a/src/math/lp/nla_intervals.h
+++ b/src/math/lp/nla_intervals.h
@@ -27,8 +27,8 @@
 namespace nla {
     class core;
 
-    class intervals : common {
-
+    class intervals {
+        core * m_core;
         class ci_value_manager {
         public:
             void inc_ref(lp::constraint_index const & v) {
@@ -138,7 +138,7 @@ namespace nla {
         im_config                   m_config;
         interval_manager<im_config> m_imanager;
         region                      m_region;
-        lp::lar_solver&             m_solver;
+        //   lp::lar_solver&             m_solver;
 
         typedef interval_manager<im_config>::interval interval;
 
@@ -151,8 +151,12 @@ namespace nla {
         bool check(lp::lar_term const& t);
 
     public:
-        intervals(core* c);
+        intervals(core* c) : m_core(c) {}
         bool check();
+        bool monomial_has_lower_bound(lpvar j) const;
+        bool monomial_has_upper_bound(lpvar j) const;
+        bool product_has_upper_bound(int sign, const svector<lpvar>&) const;
+        lp::impq get_upper_bound_of_monomial(lpvar j) const;
+        lp::impq get_lower_bound_of_monomial(lpvar j) const;
     };
-    
 } // end of namespace nla
diff --git a/src/math/lp/nla_solver.cpp b/src/math/lp/nla_solver.cpp
index 8665d1612..cde83ea8a 100644
--- a/src/math/lp/nla_solver.cpp
+++ b/src/math/lp/nla_solver.cpp
@@ -24,6 +24,7 @@
 #include "math/lp/var_eqs.h"
 #include "math/lp/factorization.h"
 #include "math/lp/nla_solver.h"
+#include "math/lp/nla_intervals.h"
 namespace nla {
 
 // returns the monomial index
@@ -54,28 +55,27 @@ void solver::pop(unsigned n) {
     }
 
         
-solver::solver(lp::lar_solver& s) {
-    m_core = alloc(core, s);
+solver::solver(lp::lar_solver& s): m_core(alloc(core, s)), m_intervals(m_core)  {
 }
 
 solver::~solver() {
     dealloc(m_core);
 }
 lp::impq solver::get_upper_bound(lpvar j) const {
-    SASSERT(is_monomial_var(j) && m_core->monomial_has_upper_bound(j));    
-    return m_core->get_upper_bound_of_monomial(j);
+    SASSERT(is_monomial_var(j) && m_intervals.monomial_has_upper_bound(j));    
+    return m_intervals.get_upper_bound_of_monomial(j);
 }
 
 lp::impq solver::get_lower_bound(lpvar j) const {
-    SASSERT(is_monomial_var(j) && m_core->monomial_has_lower_bound(j));
-    return m_core->get_lower_bound_of_monomial(j);
+    SASSERT(is_monomial_var(j) && m_intervals.monomial_has_lower_bound(j));
+    return m_intervals.get_lower_bound_of_monomial(j);
 }
 
 bool solver::monomial_has_lower_bound(lpvar j) const {
-    return m_core->monomial_has_lower_bound(j);
+    return m_intervals.monomial_has_lower_bound(j);
 }
 bool solver::monomial_has_upper_bound(lpvar j) const {
-    return m_core->monomial_has_upper_bound(j);
+    return m_intervals.monomial_has_upper_bound(j);
 }
 
 }
diff --git a/src/math/lp/nla_solver.h b/src/math/lp/nla_solver.h
index 292298742..3672ca158 100644
--- a/src/math/lp/nla_solver.h
+++ b/src/math/lp/nla_solver.h
@@ -26,11 +26,14 @@ Revision History:
 #include "math/lp/lar_solver.h"
 #include "math/lp/monomial.h"
 #include "math/lp/nla_core.h"
+#include "math/lp/nla_intervals.h"
+
 namespace nla {
 
 // nonlinear integer incremental linear solver
 class solver {
     core* m_core;
+    intervals m_intervals;
 public:
     void add_monomial(lpvar v, unsigned sz, lpvar const* vs);