Dec. 28, 2016 Update

SoCalGas would like to provide you with the following update:

 

On Saturday, December 24, 2016, as part of daily patrols and inspections, crews using infra-red camera technology observed intermittent indications of very slight releases of methane from a 2-inch opening at the SS25 wellhead at the Aliso Canyon Storage facility.

 

On December 28, SoCalGas installed a valve on the 2-inch threaded connection where methane was detected, stopping the slight release of gas. At approximately 10:45 AM SoCalGas inspected the site using an infra-red cameras and confirmed that the slight release of methane has stopped. This inspection was observed by the California Public Utilities Commission.

 

Yesterday, SoCalGas connected highly sensitive flow measurement equipment and confirmed that approximately one cubic foot of gas was released between December 24 and December 27. For additional context –  A standard home pilot light on a water heater consumes about 12 cubic feet per day, more than 10 times the amount released over the last four days. The connection of measurement equipment and the collection of measurement data were observed by the California Public Utilities Commission.

 

As the Division of Oil, Gas and Geothermal Resources (DOGGR) first reported after the leak at SS25 was permanently sealed in February, some methane may emit from the soil around the site.  According to DOGGR, “some amount of residual methane trapped in the soil is expected to seep out of the ground around the leaking well after the well is successfully controlled and then sealed.”

 

Observations indicate that recent intense rain storms triggered the very slight releases of methane previously trapped in the soil following last year’s leak at the site. Consistent with DOGGR’s expectations, slight releases may still occur at different locations near SS25.

 

All fenceline data as well as data from a vehicle-mounted monitoring device show that methane levels at the fenceline and in the community remain normal and there was no impact to the community.

 

Yesterday, The South Coast Air Quality Management District AQMD also reported that the agency had not detected elevated levels of methane in the community.

 

Since the minor release was first observed on December 24, SoCalGas has provided regular updates to the community, neighborhood council, community advisory council, and local and state elected officials, as well as appropriate agencies, including the Division of Oil, Gas and Geothermal Resources, California Public Utilities Commission, and the California Office of Emergency Service.

 

Thank you

 

Tony Tartaglia

SoCalGas External Affairs