2024 ESG Report FINAL - Report - Page 25
Environment
Managing Air Emissions
In addition to the comprehensive air monitoring programs already deployed at our re昀椀neries as required by
regulations and/or air permits, we have implemented advanced monitoring systems that go beyond regulations
to identify and reduce air emissions. Ambient air readouts allow re昀椀neries to monitor the surrounding communities
and take early response and mitigation actions even on small emissions sources. We have the following air
monitoring programs:
1. GMAP Vans Equipped with Duvas DV3000
Instruments provide real-time mobile air
monitoring and quality screenings. The vehiclemounted DV3000 is a monitoring instrument with
a gas analyzer that uses ultraviolet spectroscopy
and a meteorological station to identify and
quantify up to 14 different gases, including
benzene, SO2 and NOx , at low part-per-billion
levels. With an analyzer response time as short as
one second, the DV3000 combines measurements
with geographic mapping of gas concentrations,
and enables rapid detection and source location
of air emissions during monitoring.
2. Continuous Emissions Monitoring Systems
(CEMS) are placed in the outlet stacks of certain
昀椀red equipment (boilers and heaters) as well as
process vents like the Fluid Catalytic Cracking
Unit (FCCU). CEMS continuously measure the
concentration of compounds, such as NOx and
SO2 , exiting the stack to con昀椀rm operations are
within permitted limits.
3. Continuous Flare Monitoring Systems are
installed on 昀氀ares to measure the amount of
process gases routed to the 昀氀are for destruction
and track operational parameters to con昀椀rm the
昀氀are is operating properly.
4. Stack Testing is conducted periodically on
equipment that does not require continuous
emissions monitoring to con昀椀rm it is operating
properly and within permitted limits.
5. Leak Detection and Repair (LDAR) programs
ensure our operating sites comply with the
EPA's air quality regulations for reducing fugitive
emissions. Inspections are conducted on a routine
basis. Leaks identi昀椀ed are 昀椀xed and re-monitored
to con昀椀rm repairs were effective. In 2023, we
implemented an enhanced LDAR program using
optical gas imaging, resulting in improved leak
identi昀椀cation and cost savings.
6. Routine Optical Gas Imaging (OGI) Inspections of storage
tanks, wastewater treatment operations and other equipment
are performed using OGI cameras equipped with infrared
technology capable of detecting VOC leaks that are not
visible to the naked eye.
7. Unit Battery Limits Monitors placed around the perimeter
of re昀椀nery process units continuously measure for target
compounds. These stationary air monitors serve as an early
warning system if elevated concentrations are detected.
8. Personal H 2S Monitors are required to be worn by re昀椀nery
personnel while in and around process units, continuously
measuring for H2S, sounding an alarm and recording in the
event elevated H2S is detected.
9. Five-Gas Monitors are routinely used by personnel within
the re昀椀nery for measuring H2S, SO2 , CO, oxygen and lower
explosive limit levels for safety purposes and also as early
detection to identify and correct issues that could impact
ambient air quality.
10. Fenceline Benzene Monitors are located around a
number of our re昀椀neries at designated intervals to collect
composite samples. Additionally, stationary analyzers
that detect total VOCs or speci昀椀c compounds, such as
benzene, are deployed at certain sites in areas at or inside
the fenceline to allow for advanced noti昀椀cation of elevated
concentrations.
GLOBAL REFINING
2019
2020
2021
2022
2023
NOx (MT)
8,700
7,900
8,400
9,200
9,100
SOx (MT)
8,800
7,600
7,600
7,800
7,400
PM10 (MT)
2,200
2,200
2,600
2,400
2,200
VOCs (MT)
7,700
7,500
7,500
6,600
7,000
Fresh water withdrawn (million m3)
164.1
164.6
166.1
182.0*
187.0
Oil spill events to land (>1 bbl)
14
21
28
23
23
Oil spill events to water (>1 bbl)
3
4
0
2
2
For more information, see SASB report and the notes thereto beginning on page 76.
*Beginning in 2022, fresh water withdrawn includes volume that was withdrawn and
sold. Values in prior years include only freshwater used in Valero's operations.
Environmental, Social and Governance Report •
25
