Company X Was Responsible for 40% of the Environmental Pollutants

Company X was responsible for 40% of the environmental pollutants on a hazardous waste site whereas Company Z was responsible for the remaining 60%.Under CERCLA which of the following is true regarding the imposition of liability on the parties?

A) Company X and Company Z are subject to joint and several liability meaning that either can be held liable for the total cleanup costs, and no contribution between the parties is available.
B) Company X and Company Z are subject to joint and several liability meaning that either can be held liable for the total cleanup costs, but contribution between the parties may be available.
C) Regardless of whether both companies are still in business, Company X is responsible for only 40% of the cleanup costs, and Company Z is liable for only 60% of the costs.
D) Liability depends on who was the initial polluter because that party has primary liability for the total costs whereas the other company has secondary liability in the event that the first polluter is no longer in business.