private function downloadPantheonBackup($env) {
    $project_properties = $this->getProjectProperties();
    $terminus_site_env  = $this->getPantheonSiteEnv($env);

    $terminus_url_request = $this->taskExec('terminus backup:get ' . $terminus_site_env . ' --element="db"')
      ->dir($project_properties['web_root'])
      ->interactive(false)
      ->run();

    if ($terminus_url_request->wasSuccessful()) {
      $terminus_url = $terminus_url_request->getMessage();
    }
    else {
      $this->yell('Failed to find a recent backup for the ' . $terminus_site_env . ' site. Does one exist?');
      return FALSE;
    }

    $wget_database = $this->taskExec('wget -O vendor/database.sql.gz "' . trim($terminus_url) . '"')->run();

    if (!$wget_database->wasSuccessful()) {
      $this->yell('Remote database sync failed.');
      return FALSE;
    }

    return TRUE;
  }