CONSOLIDATED EDISON CO OF NEW YORK INC

Superfund

The sites at which O&R has been asserted to have liability under Superfund include its manufactured gas sites and the Superfund sites discussed below. There may be additional sites as to which assertions will be made that O&R has liability. For a further discussion of claims and possible claims against O&R under Superfund, see Note G to the financial statements in Item 8.

Manufactured Gas Sites

O&R and its predecessors formerly owned and operated manufactured gas plants at seven sites (O&R MGP Sites) in Orange County and Rockland County, New York. Three of these sites are now owned by parties other than O&R, and have been redeveloped by them for residential, commercial or industrial uses. The NYSDEC is requiring O&R to develop and implement remediation programs for the O&R MGP Sites including any neighboring areas to which contamination may have migrated.

O&R has completed remedial investigations and has received the NYSDEC’s decision regarding the remedial work to be performed at all seven of its MGP sites. Of the seven sites, O&R has completed remediation at four sites. Remedial construction was conducted on a portion of one of the remaining sites in 2019 and remedial design is ongoing for the other remaining sites. The company estimates that its undiscounted potential liability for the completion of the site investigation and cleanup of the known contamination on MGP sites could range from $98 million to $160 million.

Superfund Sites

O&R is a PRP at Superfund sites involving other PRPs and participates in PRP groups at those sites. The company is not managing the site investigation and remediation at these multiparty Superfund sites. Work at these sites is in various stages, and investigation, remediation and monitoring activities at some of these sites is expected to continue over extended periods of time. The company believes that it is unlikely that monetary sanctions, such as penalties, will be imposed by any governmental authority with respect to these sites.

The following table lists each of the Superfund sites for which the company anticipates it may have liability. The table also shows for each such site its location, the year in which the company was designated or alleged to be a PRP or to otherwise have responsibilities for the site (shown in the table under “Start”), the name of the court or agency in which proceedings for the site are pending and O&R’s estimated percentage of the total liability for each site. The company currently estimates that its potential liability for investigation, remediation, monitoring and environmental damages in aggregate for the sites below is less than $1 million. Superfund liability is joint and several. The company’s estimate of its liability for each site was determined pursuant to consent decrees, settlement agreements or otherwise and in light of the financial condition of other PRPs. The company’s actual liability could differ substantially from amounts estimated.