Northern Natural Gas
BMP Transmission & Storage Partner Since 2016
OMB Control No. 2060 0722
Approval expires 08/31/2021
Background
Northern Natural Gas is a subsidiary of Berkshire Hathaway Energy based in Omaha, Nebraska
and has been in business since 1930. Northern Natural Gas owns and operates the largest
interstate natural gas pipeline system in the United States. Northern Natural Gas' pipeline system
stretches across 11 states, from the Permian Basin in Texas to Michigan's Upper Peninsula,
providing access to five of the major natural gas supply regions in North America.
Northern Natural Gas, along with all of the Berkshire Hathaway Energy companies, believes
responsible environmental management is good business; it benefits our customers and improves
the quality of the environment in which we live. This belief is the basis for the Environmental
RESPECT Polk that guides our efforts and commitment in the areas of Responsibility, Efficiency,
Stewardship, Performance, Evaluation, Communication and Training.
Historical Highlights
Natural Gas Driven Pneumatic
Device Transition
Pneumatic devices powered by pressurized
natural gas are widely used throughout pipeline
systems. As part of normal operation, these
devices release or bleed natural gas to the
atmosphere. Northern Natural Gas is
systematically replacing these devices with low-
bleed or no-bleed devices.
Reduction in Pipeline Venting
During Maintenance
When maintenance is required on a natural gas
pipeline, natural gas must be vented to ensure
safe working conditions. Northern Natural Gas
has used many techniques to minimize the
amount of natural gas that is vented, including
using in-line compressors, portable compressors,
Stopples® and hot taps.
EPA Form No. 5900 413

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Northern Natural Gas Historical Fact Sheet
Pipeline Leak Detection
Northern Natural Gas conducts ground and
aerial leak detection surveys and systematically
employs cutting-edge technology for aerial leak
detection. This program has successfully
identified small leaks on the system that
otherwise may have gone undetected for longer
periods of time. Identified leaks are responded to
quickly and mitigation plans implemented as
soon as possible.
Reciprocating Compressor Rod
Packing Leak Detection
Northern Natural Gas actively monitors the rod
packing on reciprocating compressors for leaks.
By replacing the packing as leaks are detected,
instead of simply basing replacements on run
time hours, Northern Natural Gas drastically
reduces methane emissions through early
detection of leaks. At the same time, Northern
Natural Gas is saving money in replacement
costs by avoiding the unnecessary replacement
of seals that are still functioning properly.
Elimination of Wet Seal
Centrifugal Compressors
Since 2005, Northern Natural Gas has only
purchased centrifugal compressors with dry
seals. As new centrifugal compressors are
needed and old ones are replaced, this
company-wide policy contributes to our standing
commitment to reduce methane emissions. This
policy will also save money in monitoring and
seal replacement costs, impacting the bottom
line as well.
An agency may not conduct or sponsor, and a person is not required to respond to, a collection ot information unless it displays a currently valid
OMB control number. The public reporting and recordkeeping burden for this collection of information is estimated to average 14 hours per
response. Send comments on the Agency s need for this information, the accuracy of the provided burden estimates, and any suggested methods
for minimizing respondent burden, including through the use of automated collection techniques to the Director, Collection Strategies Division,
U.S. Environmental Protection Agency (2822T), 1200 Pennsylvania Ave., NW, Washington, D.C. 20460. Include the OMB control number in any
correspondence. Do not send the completed form to this address.

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