ABSTRACT
Con Edison's service territory covers more than 1,000 miles of inland and coastal shoreline in one of the most heavily regulated and scrutinized areas of the Unites States: New York City. In November 2009, the company experienced a catastrophic failure of a large transformer at a high-voltage electric substation, resulting in approximately 200 gallons of dielectric oil impacting the Bronx River. While the volume of oil was relatively small, the duration of the cleanup lasted nearly one month with costs of approximately $1.75 million, plus a nearly $1 million compliance order issued by New York State for violation of state regulations. Following this event, and through a study of all historical spill incidents, it was clear that the primary risk of spills to the environment came from the more than 30 million gallons of oil contained in the company's high-voltage transformers and oil-filled electric transmission and distribution system, which were not covered by existing Facility Response Plans developed as part of implementing OPA 90. Given these results, the company sought to refine existing spill response program elements to further reduce risks and enhance environmental stewardship.
Using the existing Spill Management Team (SMT) model in the OPA 90 program, a company-wide SMT approach was created to better prepare for and reduce the risks associated with potential spills from all company sources. The team consists of more than 50 personnel from the various business units of the company, providing direct access to a wide spectrum of skill-sets and specialties. In addition, the company has developed Oil Spill Contingency Plans (OSCP)—also covered under OPA 90—with detailed response tactics for over 300 locations.
On the heels of the program implementation, a large spill of dielectric oil from an underground high-voltage electric distribution line resulted in more than 2,000 gallons impacting the Hutchinson River. While the impact to the waterway was greater than in the 2009 event, the response duration was only 6 days with clean-up costs just over $300,000 with no state issued compliance order, a significant improvement. This result was due, in large part, to implementation of the OSCP and SMT programs. Through these experiences, the many benefits of establishing a company-wide SMT and the OSCP's were realized, including developing spill response and Incident Command System expertise, refined coordination, and improved cost management. These efforts have significantly reduced the company's spill risk exposure by improving response capabilities.
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