AQ_F_0100010_20221228_ENF_SOC-Corr_Unit1Rpt

® K I L PA T R I C K ? I" �3/ KILPATRICK TOWNSEND&STOCKTON LLP
�® 'TOWNSEND NC Department of www.kilpatricktownsend.com
ATTORNEYS AT LAW Environmental 0-Halite
Suite 1400,4208 Six Forks Road
DEC 8 2 2?
Raleigh,NC 27609
t 919 420 1700 f 919 420 1800
Winston--Salem
Regional Ufiiice
December 22 2022 direct dial 919 420 1726
direct fax [phone]
[e-mail]
kilpatricktownsend.com
Mr. Ray Stewart
Regional Air Quality Supervisor
N.C. Dept. of Environmental Quality
450 West Hanes Mill Rd, Suite 300
Winston Salem, North Carolina 27105
Re: Stericycle Facility—Haw River, North Carolina
Dear Mr. Stewart:
Please find attached written confirmation that the upgrades of Unit 1 at Stericycle's Haw
River facility were completed by November 30, 2022.
Please let me know if you have any questions or need additional information."
Sincerely,
Todd S. Roessler
Attachment
21194904V.1
ANCHORAGE ATLANTA AUGUSTA BEIJING CHARLOTTE DALLAS DENVER HOUSTON LOS ANGELES NEW YORK RALEIGH SAN DIEGO
SAN FRANCISCO SEATTLE SHANGHAI SILICON VALLEY STOCKHOLM TOKYO WALNUT CREEK WASHINGTON WINSTON-SALEM

ELDORADO ENGINEERING INC.
9089 South 1300 West,Suite 150•West Jordan,UT 84088•Tel:[phone]•Fax:[phone]
www.eldoradoengineering.com 14
NC Department of
December 20, 2022 Environmental Quality
Received
P C 2
RE: Unit 1 Upgrades at Stericycle Haw River Facility Winston-Salem
Regional Office
El Dorado Engineering can confirm that we completed the upgrades of Unit 1 at the Stericycle Haw River
facility, including:
• Wiring redone including consideration of wire routing to bypass critical components; more
robust DC power supply, including separation of power sources to bypass critical components
and non-critical components; redundant power supplies for all 24VDC devices; power supplies
with selective fuse break technology; redundant AC power supply; new control panels; new
electrical components(fuses, circuit breakers, power supplies, etc.); and new uninterruptible
power supply.
• Redundant pump for evaporative cooler brine recirculation; acid gas absorber and evaporative
cooler pumps switched from belt driven to direct driven; replace piping between the new
pumps and the system components; new,stainless steel pipe supports; convert emergency
bypass system from hydraulic to pneumatic; and replace limit switches and add new switches to
certain locations.
• New instruments;thermocouples replaced with duplex thermocouples; and redundant duplex
thermocouples in bypass critical locations.
• New HMI control and process monitoring screens; redundant HMI computers and screens; and
new control logic (automatic switching to redundant pumps, comparative logic between
redundant thermocouples, more robust alarming and interlocks, active control of process
related equipment, etc.).
All work, as described above,was completed by 11/30/22. Please feel free to contact us with any
questions.
Sincerely,
Rick O. Frandsen, P.E.
Vice President