Can the dhatu elements be considered as permanent? Can the dhatu elements (earth, water, wind and fire) be considered as permanent?
As far as I can see any thing is impermanent. What is impermanent defies description or conceptualization.

Here is more info on the subject.
http://www.buddhanet.net/cbp2_f4.htm


  All things arise due to causes and conditions. As causes and
  conditions are impermanent and will cease one day, all things will
  also cease correspondingly. When there is rising, there will be
  falling; when there is existence, there will be extinction. The rising
  and existence of things has its natural tendency towards cessation and
  extinction. It is like a wave; it comes and goes. Thus, when one sees
  the truth of "what this is, that is; this arising, that arises", one
  should also see the truth of "when this is not, that is not; this
  ceasing, that ceases". The Law of Dependent Origination pointed out
  the possibility of ending worldly suffering. It shows the way of
  liberation that corresponds to the Law of Cause and Effect.
  
  "When one is born, one will die.  One who admires high status will
  fall one day."
  
  This is the natural Law of Cause and Effect. It is also an inner
  implication of the Law of Dependent Origination. It can be called the
  Cessation Process of the Law of Dependent Origination.


As soon as one starts discussing permanence, it is already in the field of impermanence. Intellectual understanding may suggest a path. The practice of the path can lead to the unknowable. No one who has been here has ever said anything that could describe it.