Details

Autor(en) / Beteiligte

• Raybuck, M.S.
• Hermance, G.W.

Titel

Hydraulic control and containment of cyanide-containing MGP waste at a natural gas service center in Pennsylvania

Ist Teil von

• Land contamination & reclamation, 2006-04, Vol.14 (2), p.653-657

Erscheinungsjahr

2006

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• A deep abandoned storm sewer, underlying 75 000 cubic yards of waste fill and manufactured gas plant (MGP) purifier material produced a visible discharge of low-pH water in Lake Erie. The purifier material, located within a former ravine, contained cyanide, sulfur and iron, and was derived from wood chips impregnated with ferric-oxide. A second ravine to the west contained an additional 92 000 cubic yards of mixed waste and purifier material. The site, located in northwestern Pennsylvania, is an active natural gas service center. Formerly, the site was used as a gas cleanup and distribution center, where coal-derived gas from a nearby coking plant was purified and distributed. Hydrogeologie evaluations, including flux calculations, hydrologie modeling, and slope stability modeling, were conducted to assess methods to eliminate the discharge. The primary challenge was maintaining the integrity of a steep embankment, following expected groundwater elevation rises of several feet. A comprehensive remedy was implemented, involving grouting a portion of the abandoned sewer, waste consolidation, a membrane cap, storm sewer upgrades, and facility improvements. The remedy was successful, but discharge was later observed through a perpendicular sewer pipe. This sewer pipe, and associated manholes and connector piping, were subsequently lined and sealed. The site is currently approaching closure under Pennsylvania's Act 2 voluntary cleanup program. The remedial efforts were conducted without the need for costly waste removal or groundwater treatment, and allowed continued use of the site as an active service facility throughout the process.