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Fig. 5. Polished sections of (a) a fresh Fe0 filings, (b) loose Fe0 filing from the shallow up-gradient Core A collected after the first 15 mo of operation showing thin Fe (oxy)hydroxides corrosion rinds and aragonite crystals on the filing surface; (c) loose Fe0 filing from the shallow midsection of Core 1 collected 30 mo after installation showing thick Fe (oxy)hydroxide corrosion rinds from the depletion of the underlying Fe0 filing; (d) loose Fe0 filing corroding into smaller pieces from the shallow midsection of Core 1 collected 30 mo after installation; (e) scanning electron microscopy (SEM)–backscatter electron (BSE) analysis of cemented Fe0 filings from the up-gradient shallow Core A collected after the first 15 mo of operation; and (f) SEM–BSE of cemented Fe0 filings from the up-gradient shallow Core 1 collected after 30 mo of operation. [Note the smaller Fe0 filings and greater disintegration of the sample collected after 30 mo of operation (f) compared with the sample collected after the first 15 mo of operation (e).]
