[UPDATE: Oct. 12, noon] No measurable hydrogen sulfide levels were present when Air Pollution Control inspected the well in an avocado orchard at Ellwood Canyon on Tuesday. Inspectors used a handheld device, called a Jerome H2S Analyzer (J-605), which can detect between 0.003 ppm and 10 ppm. Readouts on several of Venoco’s six fence-line monitors indicate H2S levels began dropping around 3 a.m. Tuesday morning, after the well was plugged.
[UPDATE: Oct. 11, 3:30 p.m.] A private well being dug on agricultural land is the likely cause of the hydrogen sulfide releases that have been sickening some residents of west Goleta, the county announced in a press release today. The well was shut down by county Environmental Health Services on Monday at 2:30 p.m., and the well driller plugged the well and stopped the water flow late Monday night.
At 3 a.m. on Tuesday, the fence-line monitors at Venoco’s Ellwood Onshore Facility registered diminishing levels of hydrogen sulfide coming from an offsite source; the monitors within the EOF did not register H2S. The hydrogen sulfide may have taken time to dissipate, Gina DePinto, the county media liaison, said, with the wind direction in the early morning driving it toward the ocean.
Hydrogen sulfide is heavier than air, according to OSHA, and can travel along the ground or collect in low-lying areas. More information about hydrogen sulfide can be found at an OSHA site here.
The Independent will continue to update this story as more information becomes available.
[ORIGINAL STORY] Since about 4 a.m. on Sunday, residents of west Goleta have been complaining of an odor that was causing nausea and headache. The County Air Pollution Control District (APCD) stated today that Venoco’s fence-line monitor devices at its Ellwood Onshore Facility (EOF) recorded hydrogen sulfide levels of between 0.3 and 3.6 parts per million on the morning of October 9, and county inspectors are leaning toward an agricultural water well in a county area of west Goleta as the source of the smell. The OSHA exposure threshold for H2S is 10 ppm over eight hours.
Various posts to the Nextdoor social network for the Hideaway, Bluffs, and Winchester areas on Sunday stated some residents were evacuating for the day. The smell was variously described as emanating from a cat litter box, sour gas, and different from the typical rotten egg odor. According to neighbors, Southern California Gas Company stated the odor was not coming from a natural gas leak. The EOF had been transferring natural gas to keep the “pilot light” lit on the flare at Platform Holly, Venoco reps said, but was not responsible for the odor.
Mark Kram was one of those up before dawn because of the smell, and he noted winds were calm, rising later in the morning. The incident continued for about five hours, he said. An environmental scientist, Kram was alarmed the fire department had no equipment to test for “the full suite of what we were undoubtedly exposed to.” He has lived in the area for several decades and stated the smell was “far more acrid than what we typically smell.”
County Public Health, Fire Department, Office of Emergency Management, and APCD have been looking into the smell, and their inspectors are focusing on a water well being drilled on the north side of Highway 101 up in Ellwood Canyon that may have hit a pocket of hydrogen sulfide. Unlike most wells, which drill down about 500 feet, this one is at approximately 3,000 feet.
Venoco stated in a press release that its fence-line monitor detected the H2S coming from an external source. APCD was notified, per protocol; the fire department was notified separately. “In short, the systems at the EOF worked,” said Venoco’s Mike Wracher, chief operations officer.
The symptoms of hydrogen sulfide exposure include nausea, headache, respiratory symptoms, and watery eyes, all temporary, according to Air Pollution Control. Coincidentally, Venoco had a hearing last week with APCD to confirm it could suspend its off-site H2S monitor station next to Ellwood Elementary School for another year. The property is under development and discontinued the station’s lease last October; Venoco has not been able to find an alternative site.
Editor’s Note: This story was updated to indicate that the level of H2S dropped early Tuesday morning.