How are EPCRA extremely hazardous substances (EHSs) related to CERCLA hazardous substances?

There are currently about 360 EHSs defined under EPCRA section 302; over a third of them are also CERCLA hazardous substances. Aside from this overlap of listed substances, CERCLA and EPCRA also have closely related notification requirements when releases of CERCLA hazardous substances occur.