CH4 ConnectionsWhat’s Going on Underground?

By Roger C. Carson II

Operating Supervisor, Con Edison

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2

Agenda

• Con Edison Gas System Overview

• Leak Detection

• Leak Response Time

• Gas Leak Backlog Management

• Leak Pinpointing

• So What’s Going on Underground?

• Type 3 Example

• Type 1 Example

• Follow Up

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Con Edison System Overview

• System

– ~ 4300 mi – Distribution

– ~ 100 mi - Transmission

• System Materials:

– Cast Iron (~24%)

– Steel (~30%)

• Unprotected (~22%)

• Protected (~8%)

– Wrought Iron (Less than 1%)

– Plastic (~46%)

• 1.1 Million Customers

LEGENDTP > 125 PSIG

HP 15 – 99 PSIG

MP 2 – 15 PSIG

LP 4 – 12 in WC

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Leak Detection How we Receive leaks

• Leak Survey

– Monthly Survey

– Company/Contractor

– Heath Detecto-Pak Infrared (DP-IR)

– Picarro

– ABB MobileGuard

• Natural Gas Detector

• Public

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Leak Detection How we Receive leaks

• Leak Survey

– Monthly Survey

– Company/Contractor

– Heath Detecto-Pak Infrared (DP-IR)

– Picarro

– ABB MobileGuard

• Natural Gas Detector

• Public

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Leak Detection How we Receive leaks

• Leak Survey

– Monthly Survey

– Company/Contractor

– Heath Detecto-Pak Infrared (DP-IR)

– Picarro

– ABB MobileGuard

• Natural Gas Detector

• Public

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Leak Detection How we Receive leaks

• Leak Survey

– Monthly Survey

– Company/Contractor

– Heath Detecto-Pak Infrared (DP-IR)

– Picarro

– ABB MobileGuard

• Natural Gas Detector

• Public

Leak Detection (cont.)Public Awareness Campaigns

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Leak Detection (cont.)

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37%

63%

Incoming Leak Source

Public Company

Leak Response Time

10

65.60%

67.70%

71.90%

76%76.40%

78.40%80.20%80.80%80.80%

81.80%83.55%

87.57%88.89%

87.80%88.24%89.10%

89.96%

91.95%

94.10%

60.00%

65.00%

70.00%

75.00%

80.00%

85.00%

90.00%

95.00%

100.00%

20000

25000

30000

35000

40000

45000

50000

55000

60000

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019

30 min response # calls

Gas Leak Backlog Management

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0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

11,000

12,000

2000

1992 - 2018

Le

aks

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Gas Leak Backlog Management (cont.)Average time to Repair

Gas Leak Backlog Management (cont.)Multi-Faceted Approach

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Efforts: • Monthly mobile

leak survey• Public awareness

campaigns• Residential

methane detectors development and deployment

Detection Response

Efforts: • Code MuRRE• Make safe• Isolation valve

installation program

• Repair Type 3 leaks

Prevention

Efforts:• Main

replacement program leak prone pipe

• One-call, Dig safe • Training• Work

coordination with city utilities

Leak Pinpointing Factors to consider to determine leak source

• Road Conditions

– Road Composition

– Soil Type & Moisture

– Existing Utilities/Crossings

– Grade

– Unique Features

– Vegetation

• Pipe

– Material

– Existing Repairs

– Pressure

– Cover

– Odor

• Weather

– Frost

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Asphalt

Soil

Asphalt

Soil

Concrete

So What’s Going on Underground?Wall St and William St

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So What’s Going on Underground? (cont.)Wall St and William St

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Type 3 Example

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Type 3 Example

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GMI

Pogo

Type 3 Example (cont.)

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~62’

28%

Type 3 Example (cont.)

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~62’

28%

Type 3 Example (cont.)

• Main:

– 10” HPST 1971

• Road Makeup:

– Asphalt

– Concrete

– Earth

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BarholesTest Point

0%

28%

25%

15%

0%

60%

Type 3 Example (cont.)

• Main:

– 10” HPST 1971

• Road Makeup:

– Asphalt

– Concrete

– Earth

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Aerator

Highest

Reading

Type 3 Example (cont.)

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Highest

Reading

4x4

Type 3 Example (cont.)

• Main:

– 10” HPST 1971

• Road Makeup:

– Asphalt

– Concrete

– Earth

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• Reason for Leak:

– Corrosion

• Repair:

– Fullseal Clamp

TYPE 1 Example

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Manhole 11%

TYPE 1 Example

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Manhole 11%

Type 1 Example (cont.)

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Potable Water

Manhole 11%

Type 1 Example (cont.)

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Potable Water

Type 1 Example (cont.)

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Sustained ~60’s

Type 1 Example (cont.)

• Main:

– 16” MPCI 1917

• Road Makeup:

– Asphalt

– Concrete

– Earth/Rock

• Reason for Leak:

– Bell & Spigot Joint

• Repair:

– Encapsulation

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Type 1 Example (cont.)

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Potable Water

Readings

Clear

Type 1 Example (cont.)

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Sustained

Readings

Type 1 Example (cont.)

• Main:

– 6” LPCI 1904

• 1” Steel Riser

• Road Makeup:

– Asphalt

– Concrete

– Earth/Rock

• Reason for Leak:

– Corrosion on Riser

• Repair:

– Replace Riser

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Type 1 Example (cont.)

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Encapsulate

Joint

Replace Riser

Potable Water

Follow Up

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• Type 1, 2A/M, 2’s require a recheck of test points

• After 14 days within 30

• GDS does the recheck