With a .htaccess file it is possible to choose where the error log will be saved. The example below saves the log file httpd-error.log one step outside the public_html folder so it does not become public available, and sets a limit of 50 MB.
php_value error_reporting 2047 php_value error_log /your/absolute/path/httpd-error.log php_value log_errors_max_len 52428800