; and (ii) may authorize metallurgical testing of historic mine residue to determine whether reprocessing under subsection (f)(4)(B) is feasible. (C) Requirements relating to samples In conducting investigative sampling of historic mine residue, soil, or water, a Good Samaritan shall— (i) collect samples that are representative of the conditions present at the abandoned mine site that is the subject of the investigative sampling permit; and (ii) retain publicly available records of all sampling events for a period of not less than 3 years. (5) Post-sampling remediation (A) Refusal to convert permit Subject to subparagraph (B), a Good Samaritan who obtains an investigative sampling permit may decline— (i) to apply to convert the investigative sampling permit into a Good Samaritan permit under paragraph (6)