air emissions

protecting air quality

Chevron is committed to protecting air quality by managing emissions from our operations. Our air emissions Core Corporate Environmental Aspect* includes criteria pollutants [oxides of nitrogen (NOx), oxides of sulfur
(SOx) and particulate matter (PM)], volatile organic compounds (VOCs) and hazardous air pollutants. Not part of our definition of air emissions are greenhouse gases (GHGs), including methane. GHGs are included as a separate environmental aspect: energy efficiency and greenhouse gas.

of air emissions

At Chevron, we manage air emissions across the life of our operated assets through our Environmental Stewardship (ES) process, our Environmental, Social and Health Impact Assessment (ESHIA) process and our Upstream-specific Air Emissions Environmental Performance Standard (Air Emissions EPS).

The ES process requires our businesses to create an inventory of how their activities interact with the environment. These environmental aspects, including air emissions, and their related impacts are then used to identify, assess and prioritize environmental risk and improvement opportunities.

The ESHIA process is used by local project teams early in the life of a project to assess the potential impacts of our activities on air quality. An important part of this process is assessing existing environmental and social conditions, such as local air quality. This information is used during project planning to help us consider and address potentially significant air emissions from our operations in relation to local air quality.

Our Air Emissions EPS is applied across our Upstream businesses and capital projects and requires an air quality impact assessment to identify potentially significant environmental impacts associated with our air emissions. Where there is potential for significant impacts, the Air Emissions EPS specifies design requirements, such as equipment emission standards and control technologies, to reduce air emissions from our new capital projects. Our Air Emissions EPS also requires leak detection and repair programs to reduce emissions of VOCs from sources that meet the applicability requirements of the standard.

We have also made significant investments in equipment to reduce air emissions associated with our refinery operations and to meet regulatory requirements.

our performance

We collect data on our air emissions, which enables us to make informed business decisions around protection of air quality. We are committed to annually reporting performance data on the common reporting elements in the 2015 edition of the IPIECA/API/IOGP Oil and gas industry guidance on voluntary sustainability reporting, as follows:

success stories


When Tengizchevroil (TCO) was established as operator of the Tengiz Field in Kazakhstan in 1993, the field’s ongoing operations included routine flaring of associated natural gas (naturally occurring gas, not produced for commercial sale). Since then, TCO has initiated a series of major capital projects that ultimately eliminated routine flaring. Such investments have enabled TCO to reduce total natural gas flaring volumes by 85 percent since 2000; increase the gas utilization rate to more than 98 percent; and reduce total air emissions generated per tonne of oil by 73 percent – all while increasing annual crude oil volume by 159 percent.  

tengiz environment

Tengizchevroil LLP is operated by Chevron in joint venture with ExxonMobil, KazMunayGas and LukArco.

Richmond, California

Refinery modernization project
In 2016, we restarted construction activity for the Refinery Modernization Project, a $1 billion investment to replace some of our Richmond Refinery’s oldest processing equipment with more modern technology. Benefits of the project include an annual NOx reduction equivalent to removing more than 11,000 cars from Richmond streets and an annual PM​10 reduction equivalent to removing 172 big rig trucks from the Richmond Parkway. New air pollution control equipment will be installed, and upgrades will be made to improve energy efficiency, including:

  • Use of two new crude oil delivery ships with engines that go beyond current environmental requirements;
  • Addition of domes to fuel storage tanks; and 
  • Use of low-nitrogen oxide burners, furnaces and wet electrostatic precipitators to protect air quality and reduce pollution. 

Community air monitoring program
Air monitoring is one of the tools used to track emissions and help the public get a better picture of the air quality in Richmond. Since 2013, the refinery has funded a community air monitoring program in Richmond. The program, which is operated by an independent, third-party expert, Argos Scientific, provides real-time data 24 hours a day, seven days a week about air quality in our community. Data are collected and reported from three stations along the Refinery’s fence line and three neighborhood stations – North Richmond, Atchison Village and Point Richmond.

Since the launch of the program, the air monitors have continually tracked air quality. Results show that air quality in Richmond is on par with what the Bay Area Air Quality Management District is measuring in other Bay Area communities, including San Francisco and Marin County.
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*Consistent with ISO 14001, we defined seven types of environmental activities, or Core Corporate Environmental Aspects: accidental release prevention and response, air emissions, energy efficiency and greenhouse gas, natural resources (including land, water and biodiversity), site residual impacts, waste, and wastewater.

**Operated basis. Transportation includes Chevron Pipe Line Company and Chevron Shipping Company. Other includes Americas Products, International Products, Chevron Lubricants, Chevron Oronite Company, and Chevron Power and Energy Management Company. Air emissions from Chevron Business and Real Estate Services and Chevron Environmental Management Company are excluded from this reporting. For compiling and reporting air emissions data, Chevron follows regulatory definitions of VOCs. SOx emissions include SO2 and SO3, reported as SO2-equivalent. NOx emissions include NO and NO2 (reported as NO2-equivalent) and exclude N2O. Information regarding air emissions from Chevron Phillips Chemical Company LLC can be found at