What Were Manufactured Gas Plants (MGPs) and Holder Stations?
Manufactured gas plants existed from the early-1800s to the mid-1900s, prior to the development of natural gas systems, to convert coal, oil and water into gas for lighting city streets and heating homes. These plants produced byproducts such as coal tar, ash and cinders, and oils that may be present beneath these former gas plant sites. Holder stations were facilities at which manufactured gas (and later natural gas) was stored in tanks before it was distributed. Depending on their design, some of the tanks at these facilities were equipped with coal tar seals. Environmental experts have determined that former MGP and gasholder sites should be investigated, tested for possible contamination, and remediated, where appropriate.
