SNAPS Lost Hills Mid-Monitoring Newsletter - English

Lost Hills Newsletter: December 2019

Overview

CARB developed the SNAPS program to better characterize air quality in communities near oil and gas operations. Lost Hills is the first community to receive air monitoring under the SNAPS program. California’s Office of Environmental Health Hazard Assessment (OEHHA) is responsible for evaluating the potential health impacts from air pollutants measured in the SNAPS program. 

Timeline

CARB staff transported air monitoring equipment to Lost Hills in April, where staff tested the equipment for several weeks to verify that instrumentation performed correctly and data were reliable. Monitoring officially began May 20th, with more than 200 compounds being measured regularly since June. CARB has also performed mobile monitoring four times in the community so far. 

Preliminary Results

Preliminary data through August 2019 reveal that all detected compounds were below OEHHA’s acute health reference values (RELs), where applicable.  OEHHA is still evaluating potential chronic health concerns.

 PM2.5
(ug/m3)		O3
(ppb)		CO
(ppm)		H2S
(ppb)
Short-term Standard or
Acute REL		   35.0  70.0   9.0  30.0
Maximum Concentration   23.5  57.6  0.16  8.13
Average Concentration   12.5  33.9  0.12  0.29

Figure 1. Average and maximum concentrations of four pollutants measured during June-August 2019 under the SNAPS program, as compared to California’s Ambient Air Quality Standards (PM2.5, O3, CO) or OEHHA’s RELs (H2S). Real-time data for six pollutants can be found here.

The Nowcast Air Quality Index, an index based on local PM2.5 and ozone concentrations, was calculated to be “good” or “moderate” for 99.8% of the time with 0.2% of the time receiving an “unhealthy for sensitive groups” designation.

Through August, elevated levels of hydrocarbons, including methane, were typically observed in the early morning hours before sunrise. Black carbon and carbon monoxide exhibited elevated levels in both the morning and early evening, possibly attributed to motor vehicle exhaust. The highest levels of PM2.5 were typically in late afternoon and early evening, often observed with higher wind speeds.

Hourly concentrations of SNAPS pollutants relative to their average value from June-August 2019

Figure 2. Hourly concentrations of pollutants relative to their average value from June-August 2019.  

Data analysis is currently ongoing. A final report detailing results, conclusions, and short- and long-term health impacts will be released following the completion of monitoring. Additional preliminary results may be found in the attached presentation.

Next Steps

  • Continue monitoring while site lease is active
  • Analyze data and determine possible sources of the detected compounds
  • Continue evaluating detected chemicals against available Health Guidance Values
  • Continue evaluating exposure patterns
  • Release draft final report for public comment
  • Hold community meeting to discuss final report and next steps

General Program Information

Call(916) 327-5599 | Email snaps@arb.ca.gov

Air Quality/Odor Concerns

English: (916) 323-8053 | Spanish: (916) 323-0180