# # National Water Information System # 2024/11/21 # # # Date Retrieved: USGS Water Data for the Nation Help System # samp_type_cd samp_type_nm 1s 18s 1 Spike 2 Blank 3 Reference 4 Blind 5 Duplicate 6 Reference material 7 Replicate 8 Spike solution 9 Regular A Not determined B Other QA H Composite (time) K Spike Replicate P Profile