S.C. Code § 3-3-220
Certain marshlands next adjacent to Castle or Fort Pinckney, not previously ceded to the United States, and consisting of fifty acres of marshlands, more or less, were granted to the United States in 1898 for the purpose of erecting, constructing and maintaining a home or sanatorium for disabled officers, soldiers and sailors of the Army and Navy of the United States.
Land tax exempt. - Such lands shall so long as they shall be used for the purpose aforesaid be exonerated and discharged from all taxes, assessments and other charges which may be imposed under the authority of this State.
Plat to be made and filed. - The proper officers of the United States in charge of such institution were required to cause to be executed a plat of the lands which were acquired for such purpose and file it in the office of the Secretary of State of this State.
S.C. Code § 3-3-220