3:55 p.m. Update from the Office of Conservation

Bayou Corne/Grand Bayou Response Activity

Wednesday, Sep. 4 work-

Sinkhole Activity Code 3 – highest level – Seismic monitoring detected elevated fluid/gas movement signals over past day, and an isolated seismic event was observed shortly after noon today, comparatively stronger than most recent signals, but no follow-on increase in activity or surface impact has been observed as of mid-afternoon. Investigation is ongoing as to the source of that event and its potential impact. In the meantime, work within berms/directly on sinkhole continues to be suspended as a precaution while new safety protocols are finalized.

Sub-slab Sampling and Ventilation

– Continuing ambient and in-stack gas monitoring on sub-slab ventilation systems

– Vapor monitoring at 134 Sportsman and 116 Crawfish Stew

– Vapor monitoring at 10 locations where vent systems are located

– Pressure monitoring at 116 and 174 Crawfish Stew, 1438 Sauce Piquante

ORW/CPT Wells

– Perforating ORWs 3 and 46 (east of Bayou Corne, south of La. 70)

– Removing meter connections for ORWs 5 and 8 (western containment berm)

– Completing shallow aquifer monitoring well MRAA 4S (north of containment berm)

– Testing dual-phase vacuum extraction system for removal of gas from shallow sands

Containment Berm/Roads/Sinkhole

– Work on/within containment berms suspended pending approval of revised safety protocol