Blowdown notification

Blowdown details

Date: Time:

Land location:

TC Energy land agent: At TC Energy, the safety of the public and our employees is a Phone number: top priority. To ensure our pipeline system continues to meet the highest safety standards, we periodically perform routine

maintenance as part of our Pipeline Maintenance Program. As Onsite technician (blowdown co-ordinator): part of this work, you may hear a sustained loud noise known as a “blowdown.”

A blowdown is the act of releasing natural gas from the pipeline system so work can be done safely on the depressurized Cell number: facilities. TC Energy employees will close the required valves to isolate the facilities and then open a blowdown valve to safely Estimated duration of blowdown: depressurize in a controlled manner. A loud roaring sound occurs when the natural gas is released, and in some cases a Silencer in use? No silencer can be used to minimize the noise. The sound during a blowdown can be as loud as an airplane engine and may last up to 20 minutes or longer. As the flow of gas gradually slows down, the noise also lessens. The entire blowdown may last up to three hours. Wherever possible, TC Energy personnel employ silencers to minimize the noise during a blowdown.

After the natural gas is released, a funnel-shaped air expeller is placed on top of the blowdown valve opening, which draws any remaining gas out and makes it safe for activities such as welding.

Once maintenance is complete, work begins to safely bring the line back into service. Natural gas is sent back into the pipeline and, once it reaches pressure, the blowdown valve is opened once again to vent the atmospheric air. Once all the air is removed, the blowdown valve is closed. The line is then pressurized to its normal operating pressure.

Blowdowns of different types occur regularly along our pipeline system. They are part of the safe maintenance and operation of our facilities. We recognize they can be an inconvenience for our neighbours and we do everything we can to minimize the effects. On the day of the blowdown, if you live within 750 metres of where the work will occur, a TC Energy representative will visit you to provide further details on the process.

Regulatory comment

TC Energy facilities are regulated by the Energy Regulator (CER). The regulator works with TC Energy to ensure our pipelines are constructed, tested and operated safely. The CER has employees available for inquiries and to assist or advise landowners and occupants regarding pipeline problems.

If you have questions or concerns, please contact TC Energy first. General inquiries 450 – 1 Street S.W. , AB Canada, T2P 5H1 1-866-373-1601 (weekdays 7:30 a.m. to 5 p.m. MST) [email protected] In case of a pipeline emergency, call: 1-888-982-7222 TCEnergy.com January 2020 y e n k c n i p b

: y B

SW 8 SE 0

- SW

2 SW SE $ $ 1 -

0 ¯ 2

0 ( 2

: 881 - 11 - W6 d 881 - 10 - W6 e i f i 881 - 12 - W6 d o M t s a L

d x

m NW . 0 R _ r e v i e c e R _ n o i t a c i f i t o N _ n NE w NW o NW NE d w o l B _ 2 0 0 _ 0 8 4 - 0 2 0 2 \ ) 88 -1 1 - W6 3 4 2 - 0

2 SW - 88 -2 1 - W6 E 3

C 88 - 1 - W6 T (

) s l l i h r a e l C o t e k a L y a

R SE (

SW n SW SE o i s n e t x E l a r e t a L y e l s r o W

-

L T

G NW N

0 8

4 Township Road 880 - 0 2 0 2 \ e v i h c r A _ \ s t c e j o r NE P NW \ &% : NW NE W

873 - 16 - W6 SW 873 - 15 - W6 873 - 14 - W6

SE SW SE SW

NW

NE NW NE NW

872 - 17 - W6 872 - 16 - W6 872 - 15 - W6 SW

SE SW SE SW

&% Blowdown Site 0 500 1,000 metres 1500m Landowner Notification Buffer 1:20,000 (at original document size of 8.5x11) Pipe - Buried T Line

Client/Project 2020-480_002 REV 0 NOVA Gas Transmission Ltd. Prepared by BP on 2020-12-08 Worsley Lateral Extension (Ray Lake to Clearhills) Reviewed by CL on 2020-12-08 TCE-20-243

Title Blowdown Residence Notification - Receiver Notes 1. Coordinate System: NAD 1983 UTM Zone 11N 2. Base data provided by AltaLIS, CanVec, IHS 3. Imagery: DigitalGlobe Imagery Service provided by IHS Disclaimer: Aim Land Services assumes no responsibility for data supplied in electronic format. The information contained herein is compiled from various government and industry sources, subject to copyright. Aim and its data suppliers provide no warranty regarding the accuracy or completeness of this information and assume no liability for the interpretation or use thereof.