diff --git a/explorer/site-config/lungmap/dev/config.ts b/explorer/site-config/lungmap/dev/config.ts
index a2cdb6724..e476a5357 100644
--- a/explorer/site-config/lungmap/dev/config.ts
+++ b/explorer/site-config/lungmap/dev/config.ts
@@ -32,6 +32,11 @@ export function makeConfig(
   catalog: string = CATALOG
 ): SiteConfig {
   return {
+    analytics: {
+      gtmAuth: "XOKAlpBSltsrm1PKGR-fow", // GTM environment-specific
+      gtmId: "GTM-M2J5NTJ",
+      gtmPreview: "env-149",
+    },
     appTitle: APP_TITLE,
     authentication: undefined,
     browserURL: browserUrl,
diff --git a/explorer/site-config/lungmap/prod/config.ts b/explorer/site-config/lungmap/prod/config.ts
index 8da83d400..b63348f93 100644
--- a/explorer/site-config/lungmap/prod/config.ts
+++ b/explorer/site-config/lungmap/prod/config.ts
@@ -14,4 +14,12 @@ const config: SiteConfig = {
   ...makeConfig(BROWSER_URL, PORTAL_URL, DATA_URL),
 };
 
+// Update gtmAuth for the prod environment lookup.
+if (config.analytics) {
+  const analytics = { ...config.analytics };
+  analytics.gtmAuth = "WB1d2Aoi1q3GOmQMSGMsZA";
+  analytics.gtmPreview = "env-150";
+  config.analytics = analytics;
+}
+
 export default config;