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on one offshore gathering system. This allowed ~75,000 BBL (11.9 MM L) of seawater to enter the trunkline, and ~40,000 bbl (6.4 million L) of seawater to enter the lateral. NACE CORRO- SION 2010 paper no. 10064 described the breach, the spool piece to repair to the trunkline and reconnect the lateral, the dewatering operations, and the high concentration of H2 S that was detected. That paper also described the mainte- nance pigging, chemical treatments, and sample analyses/monitoring program, which were used to reattain control over the corrosion mechanisms that could threaten the integrity of the pipeline if left unchecked. The May 3, 2010 issue of Oil and Gas Journal presented "Aggressive Moves Counter SRB in Flooded Subsea Pipeline," which was an encapsulated version of the NACE paper. Subsequent to those publications, we had an opportunity to examine (a) a spool piece, which was temporarily installed in the replacement connection to the lateral, prior to the availability of the pressure boundary safety joint (PBSJ) and (b) a metal coupon removed from the trunkline when a new pipe was connected to the trunkline. The examination of the \MUXWZIZa [XWWT XQMKM _I[ [QOVQÅKIV\ since it was installed just before the lateral was dewatered, and was only subject to flow once production resumed. This KWVÅZUML \PI\ \PM KPMUQKIT \ZMI\UMV\[ and maintenance pigging programs were effective in protecting the base metal, once the line was dewatered and produc- tion resumed. The examination of the metal cou- pon removed from the trunkline was [QOVQÅKIV\ [QVKM Q\ PIL JMMV []JRMK\ML to the conditions within the pipe when it was breached, as well as through the dewatering operations and subsequent return to operations. We presented these observations in CORROSION 2012 paper no. 0001098, and the highly edited (shortened) version, "Initial Cor- rosion Products Protect a Pipeline from Microbiologically Generated H2 S," in the August 2012 issue of MP. In this paper and article, we reported that we could VW\ ÅVL IVa LQ[\QVK\ QZWV []TÅLM QV \PM corrosion products on the metal coupon removed from the trunkline, despite the elevated H2 S detected during dewatering operations. However, we found evidence for the presence of a complex, sulfated hydrated iron oxyhydroxide. Please note that in the CORROSION 2010 paper no. 10064, we reported the gas normally transported through the trunkline had at most only an occasional trace of H2 S, and we also noted that serial dilution studies and APS reductase tests of multiple sam- ples of water removed from the pipeline during the initial dewatering operations evidenced SRB populations between 10,000 and 1,000,000 per mL. Thus, the elevated concentrations of H2 S, as reported in the papers, is consistent with XWX]TI\QWV[ WN ;:* \PI\ _MZM Y]IV\QÅML during the initial dewatering operations for removing the seawater from the breached pipelines. (No other sources for the H2 S could be found.) Continued on page 12 NACE International, Vol. 51, No. 11 November 2012 MATERIALS PERFORMANCE 11