diff --git a/src/ert/config/parsing/config_schema.py b/src/ert/config/parsing/config_schema.py
index 6adba3c9cba..bd2d03ac395 100644
--- a/src/ert/config/parsing/config_schema.py
+++ b/src/ert/config/parsing/config_schema.py
@@ -295,6 +295,7 @@ def init_site_config_schema() -> ConfigSchemaDict:
     for item in [
         positive_int_keyword(ConfigKeys.MAX_SUBMIT),
         positive_int_keyword(ConfigKeys.NUM_CPU),
+        string_keyword(ConfigKeys.REALIZATION_MEMORY),
         queue_system_keyword(True),
         queue_option_keyword(),
         job_script_keyword(),