Facility Description
The University of California, Santa Barbara (UCSB) is a university campus located in Santa Barbara, California with numerous emitting devices permitted with the District.  Natural gas–fired external combustion equipment is used for space heating and diesel-fired internal combustion engines are used for emergency backup power.  Additional emission sources include a gasoline-fueling station, paint spray booths, laboratory processes, and a hazardous waste collection center (HWCC). The facility and its emitting sources currently operate under District Permit to Operate 13725-R3 and Part 70 Operating Permit 13725.

Location
UCSB is located just north of the City of Santa Barbara near Goleta, California on 1,055 acres adjacent to the Pacific Ocean.

Description of Processes Emitting Toxic Emissions
Toxic Air Contaminants (TACs) are emitted from combustion sources including hot water heaters, furnaces, kilns, cooktops, boilers and internal combustion engines.  In addition, TACs are released from laboratory fume hoods in engineering and science buildings throughout the campus.  Small amounts of TACs are released from the collection and storage of community hazardous waste (e.g., paint, antifreeze) at the HWCC.  Other TAC emission sources operate in support of the campus, such as a paint booth for painting of wood and metal office and classroom furniture and equipment, and a gasoline-fueling station for the Marine Biotechnology Laboratory.

Health Risk Assessment Results
Cancer risk and non-cancer Hazard Index (HI) risk values were calculated and compared to significance thresholds adopted by the District’s Board of Directors. The 2018 Health Risk Assessment Report is available upon request (email [email protected]). The calculated risk values and applicable thresholds are as follows (with significant risks shown in red):

*Risk after the Risk Reduction Audit and Plan (RRAP) is fully implemented.  See Risk Reduction section below for details.

** The RRAP Risk Footprint shows the acute non-cancer isopleth of 0.1 (not significant) after the implementation of the RRAP.  

Based on these results, the operations at the University of California, Santa Barbara stationary source in 2018 did not present a significant cancer or chronic non-cancer risk to the surrounding community.  However, there is a significant onsite and offsite acute non-cancer risk.  UCSB submitted a Risk Reduction Audit and Plan (RRAP) on December 9, 2025 to reduce the acute non-cancer risk.  The District reviewed the RRAP, confirmed that the risk reduction measures will reduce the acute non-cancer risk below the District’s significance risk threshold, and approved the RRAP on February 24, 2026.

Risk Driving Toxic Emissions

There are three locations with a significant risk footprint: 1) the point of maximum impact (PMI) at the Marine Biotechnology Laboratory; 2) the Geology building, Webb Hall; and 3) the Facilities Management offices (which are no longer present).  The risk driving pollutant and device for each risk footprint is discussed below.

Marine Biotechnology Laboratory
Benzene (opens in a new tab), emitted from the Marine Biotechnology Laboratory gasoline dispensing facility (GDF), is the primary driver for the acute non-cancer risk at the PMI.  The primary health endpoints for the acute non-cancer risk at the PMI are the immune, hematologic (blood), and reproductive/developmental systems.  The primary cancer risk drivers at the PMI are combustion products: arsenic (opens in a new tab), polycyclic aromatic hydrocarbons (PAHs) (opens in a new tab), diesel particulate matter (opens in a new tab), and cadmium (opens in a new tab).  The chronic non-cancer risk driver at the maximally exposed individual resident (MEIR) is arsenic (opens in a new tab).  The primary health endpoint for chronic non-cancer risk at the MEIR is the respiratory system. The primary 8-hour chronic non-cancer risk driver at the MEIR is nickel (opens in a new tab), with arsenic (opens in a new tab), acrolein (opens in a new tab), and formaldehyde (opens in a new tab) as secondary risk drivers, all of which are combustion products.  The primary health endpoint for 8-hour chronic non-cancer risk at the MEIR is the respiratory system.  UCSB’s entire Facility Emissions Summary is available here (opens in a new tab).

Webb Hall
Acrolein (opens in a new tab), emitted from a natural gas generator at the Geology building, was the primary risk driver for the significant acute non-cancer risk at Webb Hall.  The primary health endpoints for the acute non-cancer risk at Webb Hall were the eyes and the respiratory system.  The natural gas generator used at the Geology building is no longer present.  For that reason, the calculated risk at Webb Hall was reduced below the District’s significance threshold.

Facilities Management Offices
Benzene (opens in a new tab), emitted from the GDF at the Facilities Management Yard, is the primary risk driver for the significant acute non-cancer risk at the Facilities Management offices.  The primary health endpoints for the acute non-cancer risk at the Facilities Management offices are the immune system, hematologic (blood) system, and reproductive/developmental systems.  The Facilities Management offices and the GDF at the Facilities Management Yard are no longer present.  Therefore, the significant risk at this location is no longer present.

Public Notification
The 2018 operations at UCSB created a significant acute non-cancer risk onsite and on a small portion of the beach adjacent to UCSB’s Marine Biotechnology Laboratory.  Because there are no businesses or residences within the significant risk isopleth, an online public notification is being conducted in lieu of the traditional mailing. The public notification page for UCSB’s HRA is located here (opens in a new tab).

Risk Reduction
Because this facility’s health risk assessment indicates a significant risk, the facility operator was required to conduct an airborne toxic risk reduction audit and develop a plan to implement airborne toxic risk reduction measures. UCSB submitted their Risk Reduction Audit and Plan (RRAP) on December 9, 2025, which is available here (opens in a new tab). The District conditionally approved the RRAP on February 24, 2026. The District’s conditional approval letter is available here (opens in a new tab). The following measures are enforceable elements of the RRAP:

1. Measure 1 – Install Phase II Emissions Controls and Limit Hourly Gasoline Dispensing Rate. UCSB proposed to modify the GDF at the Marine Biotechnology Laboratory to install Phase II emission controls and to limit the hourly dispensing rate of gasoline.  Because hourly records for dispensing gasoline in 2018 were not kept, the maximum amount possible to dispense within one hour (500 gallons) was assumed for the HRA, which may be more than was dispensed in any one hour.  In addition to limiting their hourly dispensing rate of gasoline, the RRAP requires monitoring and recording to accurately track the dispensing rate and ensure the hourly limit is not exceeded.
2. Measure 2 – Update Acute Non-Cancer Modeling Using ARAM.  UCSB updated the acute non-cancer risk modeling with the Alternative Refined Acute Method (ARAM) described in Appendix H of the District’s Form-15i (opens in a new tab). In addition to the emission reduction from Risk Reduction Measure No 1. above, the updated modeling also included the removal of emitting devices that are no longer operating at UCSB, including the risk driving devices at Webb Hall and the Facilities Management offices.  The removal of these devices and updating the modeling using ARAM showed that the risk at Webb Hall (Geology building) and the Facilities Management offices was reduced below the District’s significance threshold.

Implementation of the measures noted above will reduce UCSB’s risk below District’s significance thresholds at all locations.

More information about the AB 2588 program can be found at the District’s AB 2588 Air Toxics “Hot Spots” Program (opens in a new tab) webpage.