Permissions on /var/log/httpd
Solution 1:
The apache user needs to be able to traverse the directory tree to /var/log/httpd so ensure that at some permission level each of the directories /var, /var/log and /var/log/httpd have an x bit set that will allow this.
Check that there are no acls set that affect the apache user getfacl can help you determine this.
Check that there are no extended file attributes that are affecting the apache user lsattr with explanation in the chattr manual.