Sampling acid mine drainage (AMD) or natural acid rock drainage (ARD)-
impacted sediments is complex, requiring appropriate field sampling te
chniques to ensure representative samples that are both repeatable and
reproducible. The important factors affecting sampling of riverine se
diments are examined. These include sample site location, field observ
ations, representative sampling, sample collection techniques, and sam
ple preservation. A recommended sampling and processing protocol is pr
esented for AMD- and ARD-impacted riverine sediments, which includes s
ediment sampling, Fe hydroxide flee sampling, chemical analysis, inter
stitial (pore) water collection, sediment elutriates, sediment fractio
nation, and physical analysis. The importance of bioassay testing is d
iscussed, as is quality assurance and assessment approaches to define
sediment quality criteria.