Rangers are not all perfect - some are volunteers and not overly trained but do have a strong desire to protect our natural resources for future generations. That in itself isn't all bad is it? My advise is to do as they suggest. You will cause no problems by sending everything Grey and Black down the black water dump station. I suggest we do what we can to keep the peace and to keep our SHARED parks as pristine as we can so that everyone, even those not yet born can also enjoy the real beauty these parks offer us. Most of all enjoy and respect your parks!!