Leak Survey Results – March 16, 2016

On Jan. 26, 2016, the California Public Utilities Commission’s (CPUC) Safety and Enforcement Division (SED) directed all California natural gas storage operators to immediately inspect all natural gas storage facilities for leaks and report the information to the state. The operators submitted their results in February and SED utilized independent criteria from the Gas Piping Technology Committee (GPTC), which includes experts from the federal Pipeline and Hazardous Materials Safety Administration and the National Transportation Safety Board, to ensure all identified leaks were repaired or are in the process of being repaired.

Ninety-five percent, or 218, of the 229 leaks reported across all natural gas storage fields between October 26, 2015 and February 5, 2016, were non-hazardous and required minor responses such as tightening or lubricating valves. Eight were “Grade 1”, meaning that they potentially posed a safety hazard. Those eight leaks have been addressed: six leaks were repaired and two leaks no longer exist because there is currently no gas within related wellhead components (components must be repaired before gas is reintroduced). Gill Ranch Storage, PG&E, and Wild Goose Storage are completing repairs on the remaining 22 non-hazardous leaks. SED will conduct a follow-up inspection to verify that the remaining 22 leaks are repaired. In summary, as a result of this survey and the mandatory remedial action taken there are no immediate or probable future hazards in California related to gas leaks. Going forward, daily leak monitoring, as required by the Division of Oil, Gas and Geothermal Resources (DOGGR), is in place and will ensure quick identification of hazards. DOGGR , in coordination with the California Air Resources Board (ARB), will further refine the daily requirements.

All the identified leaks were above ground (not leaking from the well storage zone) except for one below ground leak on a flange, which has been repaired.

Please find below examples of the leaking components.

 

Identified Leak
Example of one of the identified leaks (image 1)  Example of one of the identified leaks (image 2) 
Examples of one of the identified gas leaks. Examples of one of the identified gas leaks.

 

 

 Below are the GPTC Leak Classification and Action Criteria Guidelines:

TABLE 3A-LEAK CLASSIFICATION AND ACTION CRITERIA-GRADE 1 

Leak Classification and Action Criteria
GRADE  DEFINITION  ACTION CRITERIA  EXAMPLES 
1 A leak that represents an existing or probable hazard to persons or property, and requires immediate repair or continuous action until the conditions are no longer hazardous. Requires prompt action* to protect life and property, and continuous action until the conditions are no longer hazardous. *The prompt action in some in-stances may require one or more of the following:
a. Implementation of company emergency plan(§192.615).
b. Evacuating premises.
c. Blocking off an area.
d. Rerouting traffic.
e. Eliminating sources of ignition.
f. Venting the area. g. Stopping the flow of gas by closing valves or other means.
h. Notifying police and fire departments.
1. Any leak which, in the judgment of operating personnel at the scene, is regarded as an immediate hazard.
2. Escaping gas that has ignited.
3. Any indication of gas which has migrated into or under a building, or into a tunnel.
4. Any reading at the outside wall of a building, or where gas would likely migrate to an out-side wall of a building.
5. Any reading of 80% LEL, or greater, in a confined space.
6. Any reading of 80% LEL, orgreater in small substructures (other than gas associated sub- structures) from which gas would likely migrate to the outside wall of a building. 7. Any leak that can be seen, heard, or felt, and which is in a location that may endanger the general public or property.

TABLE 3B-LEAK CLASSIFICATION AND ACTION CRITERIA-GRADE 2 

Table 2
GRADE  DEFINITION  ACTION CRITERIA  EXAMPLES 
2 A leak that is recognized as being non-hazardous at the time of detection, but justifies scheduled repair based on probable future hazard. Leaks should be repaired or cleared within one calendar year, but no later than15 months from the date the leak was reported. In determining the repair priority, criteria such as the following should be considered: 
a. Amount and migration of gas. 
b. Proximity of gas to buildings and subsurface structures.
c. Extent of pavement. 
d. Soil type and soil conditions (such as frost cap, moisture and natural venting). 

 

 Grade 2 leaks should be reevaluated at least once every six months until cleared. The frequency of reevaluation should be determined by the location and magnitude of the leakage condition. Grade 2 leaks may vary greatly in degree of potential hazard. 

Some Grade 2 leaks, when evaluated by the above criteria, may justify scheduled repair within the next 5 working days. 

Others will justify repair within 30 days. During the working day on which the leak is discovered, these situations should be brought to the attention of the individual responsible for scheduling leak repair. 

On the other hand, many Grade 2 leaks, because of their location and magnitude, can be scheduled for repair on a normal routine basis with periodic re-inspection as necessary.

A. Leaks Requiring Action Ahead  of Ground Freezing or Other Adverse Changes in Venting Conditions.  Anyleak which, under frozen or other adverse soil conditions, would likelymigrate to the outside wall of a building. 
 
B. Leaks Requiring Action Within  Six Months  
1. Any reading of 40%LEL, or greater, under a sidewalk in a wall-to-wall paved area that does not qualify as a Grade 1 leak. 
2. Any reading of 100% LEL, or greater, under a street in a wall-to-wall paved area that has significant gas migration and does not qualify as a Grade 1 leak. 
3. Any reading less than 80% LEL in small substructures (other than gas associated substructures) from which gas would likely migrate creating a probable future hazard. 
4. Any reading between 20% LEL and 80% LEL in a con-fined space. 
5. Any reading on a pipeline operating at 30 percent SMYS, or greater, in a class 3 or4 location, which does not qualify as a Grade 1 leak. 
6. Any reading of 80%LEL, or greater, in gas associated sub-structures. 
7. Any leak which, in the judgment of operating personnel at the scene, is of sufficient magnitude to justify scheduled repair.

TABLE 3C-LEAK CLASSIFICATION AND ACTION CRITERIA-GRADE 3 

Table 3

GRADE 


DEFINITION 


ACTION CRITERIA 

EXAMPLES 

3 

A leak that is non-hazardous
at the time of detection and can be reasonably expected to remain non-hazardous.


These leaks should be reevaluated during the next scheduled survey, or within 15 months of the date reported, whichever occurs first, until the leak is regraded or no longer results in a reading.


Leaks Requiring Reevaluation at Periodic Intervals 

 
1. Any reading of less than
80% LEL in small gas associated substructures.
2. Any reading under a street in areas without
wall-to-wall paving where it is unlikely the gas could migrate to the out-side wall of a building.
3. Any reading of less than
20% LEL in a confined space.

 

The GPTC is a consensus group made up of representatives from the distribution, transmission, and manufacturing sectors of the natural gas industry; the National Association of Pipeline Safety Representatives (NAPSR), the Pipeline and Hazardous Materials Safety Administration (PHMSA), and the National Transportation Safety Board.

Under current federal regulations, gas storage facility operators monitor their own facilities for gas leaks. Specifically, SED oversees compliance with Code of Federal Regulations (CFR) 49, Part 192, which requires the operators of the gas storage facilities to adopt leak management programs for their pipelines, prescribes minimum frequencies for leakage surveys, and provides leak classification criteria, action and abatement criteria, qualifications for leak surveyors and leak identification technology. The minimum leak survey frequency for gas pipelines, including active and abandoned wells within storage facilities, is once every calendar year. For pipelines in densely populated areas, the leak survey requirement is at least twice each calendar year. SED engineers review leakage survey inspection records for compliance with 49 CFR, Part 192 requirements. When an operator is not compliant with these regulations regarding leak monitoring, SED issues notices of probable violations and requires remedial actions.

The ARB is addressing equipment leaks through an ongoing regulatory process to reduce greenhouse gas emissions from the oil and gas sector, which includes natural gas storage.The draft regulatory language includes quarterly leak detection and repair surveys, which requires each component be checked and, if leaking, repaired in a timeframe corresponding to the leak level. In addition to component level checks, monitoring for larger leaks is occurring daily under the monitoring plans in DOGGR’s emergency regulations, as mentioned above. The ARB is working with DOGGR on permanent monitoring plan requirements to reside in either DOGGR or ARB regulations. The potential for continuous monitoring is being evaluated. ARB plans to bring its proposed regulation to the Board in July with a subsequent Board Hearing in late 2016/early 2017. Further information can be found at: www.arb.ca.gov/cc/oil-gas/oil-gas.htm.

In addition, the CPUC is examining if additional leak survey requirements are necessary in the transmission and distribution sector.. The CPUC initiated Rulemaking R.15-01-008 in January 2015 to implement provisions of Senate Bill 1371, which requires the CPUC, in consultation with California Air Resources Board, to consider developing rules and policies for the operation, maintenance, repair, and replacement of CPUC-regulated gas pipeline facilities, in order to meet the greenhouse gas reduction goals of Assembly Bill 32. Further information can be found on the webpage for the Rulemaking.

SED’s Jan. 26, 2016, directive represents one of the CPUC’s responses to the leak at the Aliso Canyon Natural Gas Storage facility operated by SoCalGas. SED is currently directing an independent investigation into the cause of gas leak at the Aliso Canyon facility and will determine if the facility operator violated any laws or regulations. Other agencies, such as DOGGR, are conducting separate investigations and have introduced updated regulations focused on protecting safety, public health, and air quality at and around gas storage facilities. The ARB will finalize the quantification of the leak, conduct additional fly-overs to evaluate leakage at all storage facilities, and move ahead with the above-mentioned regulations.

Additionally, DOGGR is undertaking enforcement activities for gas storage facilities. All wells in the Aliso Canyon storage field must pass a thorough inspection before any injection can resume in the field. Statewide, under emergency regulations that took effect on February 5, 2016, operators are required to comply with new safety measures, including daily inspections of gas storage wells, which will incorporate input from the ARB. DOGGR has begun a public process to make those regulations permanent.

Leak Survey Results Summary 

Leak Survey Results Summary

Facility 

Leaks Found 

Leaks Repaired 

Classification 

Location of Leak 

Remedial Actions 

Aliso Canyon

66

66

Minor non-hazardous

Above Ground

Tightening, adjustment, lubrication or replacement of parts or piping.

Goleta

17

17

Minor non-hazardous

Above Ground

Tightening, adjustment, lubrication or replacement of parts or piping.

Honor Rancho

1

1

Non minor non-hazardous

Above Ground

Tightening, adjustment, lubrication or replacement of parts or piping.

Honor Rancho

13

13

Minor non-hazardous

Above Ground

Tightening, adjustment, lubrication or replacement of parts or piping.

Playa Del Rey

3

3

Minor non-hazardous

Above Ground

Tightening, adjustment, lubrication or replacement of parts or piping.

Montebello

6

6

Minor non-hazardous

Above Ground

Tightening, adjustment, lubrication or replacement of parts or piping.

Wild Goose Storage, LLC

27

21

3(High priority)
8(Medium priority)
16(Low priority)

All Above Ground

21 leaks repaired and began corrective actions to address the remaining 6 leaks but final repair has not been completed yet.

Lodi

0

0

Not applicable

Not applicable

Not applicable

Central Valley Gas Storage

2

2

Grade 3

Above Ground

Repaired on 2/4/16 and 2/5/16

Gill Ranch Storage

10

1

1 (Grade 2)
9 (Grade 3)

Above Ground

Grade 2 leak was repaired 2/9/16. Grade 3 leaks were schedule to be repaired within 60 days.

Los Medanos

23

23

8 (Grade 1)
18 (Grade 2)
58 (Grade 3)

Above Ground

7 leaks are awaiting remedial action. PG&E completed remediation of 17 leaks of the 24 leaks as of 3-6-2016. The remaining 2 Grade 1 leaks are blown down and not leaking at the moment but require assistance from third party vendor to complete the repair.

Plesant Creek

29

29

Above Ground

McDonald Island

32

25

23 (Above Ground)
1 (Below Ground)

 

   

 Leak Survey Results