diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09c7ba0..ffbefd3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,10 @@ This file documents all notable changes to the GEOS-Chem Classic wrapper reposit
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased] -- TBD
+### Removed
+- `BPCH_DIAG` configuration option
+
 ## [14.3.0] - 2024-02-07
 ### Changed
 - Updated GEOS-Chem submodule to 14.3.0
diff --git a/CMakeScripts/GC-ConfigureClassic.cmake b/CMakeScripts/GC-ConfigureClassic.cmake
index 67a98d0..b8d1ca1 100755
--- a/CMakeScripts/GC-ConfigureClassic.cmake
+++ b/CMakeScripts/GC-ConfigureClassic.cmake
@@ -49,19 +49,6 @@ function(configureGCClassic)
     set(MECH "fullchem" CACHE STRING "Name of the chemistry mechanism to use")
     gc_pretty_print(VARIABLE MECH OPTIONS "fullchem" "carbon" "Hg" "custom")
 
-    #-------------------------------------------------------------------------
-    # Turn on bpch diagnostics?
-    #-------------------------------------------------------------------------
-    set(BPCH_DIAG "OFF" CACHE BOOL 
-        "Switch to enable GEOS-Chem's bpch diagnostics"
-    )
-    gc_pretty_print(VARIABLE BPCH_DIAG IS_BOOLEAN)
-    if(${BPCH_DIAG})
-        target_compile_definitions(GEOSChemBuildProperties
-	    INTERFACE BPCH_DIAG
-	)
-    endif()
-
     #-------------------------------------------------------------------------
     # Set USE_REAL8 as cache variable so as to not override existing definition
     # See https://github.com/geoschem/geos-chem/issues/43.