Each of our business units is responsible for quantifying emissions and reporting the information to our corporate center for compilation and internal verification. Reporting to authorities and regulators is also the responsibility of business units.

The method of data collection at each individual source ranges from continuous emissions monitoring to emissions estimations. Estimating approaches meet applicable regulatory reporting requirements or industry guidance, as appropriate. The quality of estimating methodologies, measurements and calculations are audited on a routine schedule by our corporate HSE auditing team and periodically assessed by third parties.

We conduct independent third-party limited assurance for scope 1, scope 2 and scope 3 emissions annually. The verification and assurance process for 2019 data will consist of independent third-party limited assurance of scope 1, scope 2 and scope 3 GHG emissions, as well as selected environmental and safety metrics including energy use, flaring, water use, criteria air pollutants, waste and liquid hydrocarbon spills. That assurance will be complete in fall 2020. See our most recent ERM CVS Assurance Statement.

Read more about our internal quality assurance and third-party verification.