How frequently do O’Brien and Gere check the systems after they are running?
As required by USEPA/NJDEP, DuPont collects a post-mitigation indoor air sample a minimum of 30 days after the system is installed and running. A second post-mitigation indoor air sample is required if the first sample is not collected between November 1st and March 31st. In addition, DuPont shall inspect the vapor intrusion mitigation systems at each building on a quarterly basis for the first year. Assuming that the system does not require re-commissioning, DuPont can reduce the frequency of inspections to annually after the first year.
