diff --git a/env.example b/env.example
index 9f2fe44..75ebcb7 100644
--- a/env.example
+++ b/env.example
@@ -2,6 +2,7 @@ BIBLIO_SOLR='http://biblio-server/solr'
 SOLRCLOUD_URL='http://solr-cloud-server/solr'
 BROWSE_SOLR='http://catalog-solr-server/solr'
 CALLNUMBER_CORE='callnumbers'
+CALLNUMBER_COLLECTION='callnumbers'
 AUTHORITY_CORE='authority_core'
 AUTHORITY_COLLECTION='authority_collection'
 SOLR_USER='solr'