S.C. Code § 51-3-60
Any South Carolina resident who is over sixty-five years of age or disabled or legally blind as defined in Section 43-25-20 of the 1976 Code may use any facility of a state park except campsites, overnight lodging and recreation buildings without charge. Such residents may also use campsite facilities at one-half of the prescribed fee. A person exercising this privilege on the basis of age shall present his medicare card or other card approved by the South Carolina Commission on Aging to the employee of the State Department of Parks, Recreation, and Tourism who is in charge of the particular state park, and a person who is disabled or legally blind shall present to such person in charge of the park a certificate to that effect from a licensed doctor of medicine or an official of an agency authorized by law to make determinations of disability or blindness. The authorization for use of the facilities as provided by this section shall not be effective if it conflicts with any federal law, rule or regulation.
The term "disabled" as used herein shall mean the inability to perform substantial gainful employment by reason of a medically-determinable impairment, either physical or mental, which has lasted or is expected to last for a continuous period of twelve months or more.
Any South Carolina resident who is a veteran and who has been classified by the Veterans Administration as permanently and totally disabled may also enter any state park without charge upon presentation to the person in charge of the park of an identification card from the county veterans affairs officer stating the veteran's permanent and total disability. A statement of age or disability may not be made for any person whose age and disability records are not maintained in the veterans affairs office at which the request is made.
S.C. Code § 51-3-60