News Details

FINAL UPDATE 8/24/17: SoCalGas Natural Gas Monitoring & Main Replacement

Vicinity of Archibald and La Gloria


This page was created in order to educate Rancho Cucamonga residents on the topic of natural gas and to provide updates on the natural gas leak, repair, and extraction around the vicinity of La Gloria and Archibald Avenue.  SoCalGas repaired the leak on May 9th and after extraction (updates and data provided by SoCalGas are below) continued to monitor with a formal Post Extraction Monitoring Plan (document below) and provided FINAL Update and Barhole Monitoring Reads to the City of Rancho Cucamonga early evening 8/23/17.

The Final Update documents from SoCalGas regarding this incident near the vicinity of Archibald and La Gloria are labeled as FINAL and provided below -

The City of Rancho Cucamonga is posting information from SoCalGas Company as a public service; however, the city is not attesting to the accuracy of the contents or the conclusions provided by SoCalGas Company.  

Quick Links:  8.11.17 SoCalGas Confirmation Sampling Plan by Geosyntec

SoCalGas Company Incident Information/Updates Webpage 

AQMD Rancho Cucamonga Incident & Monitoring Webpage

AQMD Rancho Cucamonga Incident Monitoring & Data

 6.7.17 City Council Meeting PowerPoint Presentation presented by SoCalGas

VIew Video of 6.7.17 City Council Administrative Hearing Item Presentation & Discussion

 SoCalGas Post Extraction Monitoring Plan

OES Hazardous Material Spill Report

Recent natural gas leaks in Los Angeles County and the Inland Empire have raised public awareness of the issue. Recent media stories have focused on the issue of natural gas leaks in neighborhoods and their potential impact on the health and safety of residents.

The following page was created in order to educate Rancho Cucamonga residents on the topic of natural gas and to provide an update on the recent natural gas leak, repair and extraction around the vicinity of La Gloria and Archibald Avenue.

SoCalGas provided the following map and data charts to the City of Rancho Cucamonga; questions regarding this information should be directed to SoCalGas Company (contact info below).

8.21.17 FINAL Methane Monitoring Locations     8.21.17 FINAL Confirmation Sampling Data

8.21.17 FINAL SoCalGas Summary of RC Readings

7.10.17 Methane Concentration Map    7.10.17 Methane Concentration Data

7.7.17 Methane Concentration Map      7.7.17 Methane Concentration Data

7.5.17 Methane Concentration Map      7.5.17 Methane Concentration Data

6.30.17 Methane Concentration Map    6.30.17 Methane Concentration Data

6.26.17 Methane Concentration Map    6.26.17 Methane Concentration Data

6.23.17 Methane Concentration Map    6.23.17 Methane Concentration Data

6.21.17 Methane Concentration Map    6.21.17 Methane Concentration Data

6.19.17 Methane Concentration Map    6.19.17 Methane Concentration Data

6.16.17  Methane Concentration Map   6.16.17 Methane Concentration Data 

6.14.17 Methane Concentration Map    6.14.17 Methane Concentration Data

6.13.17 Methane Concentration Map    6.13.17  Methane Concentration Data

6.12.17 Methane Concentration Map     6.12.17 Methane Concentration Data

6.11.17 Methane Concentration Map      6.11.17 Methane Concentration Data

6.10.17 Methane Concentration Data SoCalGas comparative to AQMD

6.10.17 Methane Concentration Map      6.10.17 Methane Concentration Data

6.9.17 Methane Concentraction Map      6.9.17 Methane Concentration Data

6.8.17 Methane Concentration Map        6.8.17 Methane Concentration Data

6.7.17 Methane Concentration Map        6.7.17 Methane Concentration Data 

*Note:  Initial incident Vapor Readings starting 5.8.17 can be found on Table 4; Page 28 of Concentration Data file

6.6.17 Methane Concentration Map        6.6.17 Methane Concentration Data

Monitoring Location Map                   6.5.17 SoCalGas Monitoring Data

Latest SoCalGas Information Sheets 

7.10.17 Monitoring & Main Replacement Update

7.5.17 Monitoring & Main Replacement Update

6.30.17 Monitoring & Main Replacement Update

6.27.17 Extraction Update

6.23.17 Extraction Update

6.21.17 Extraction Update

6.19.17 Extraction Update

6.17.17 Extraction Update

6.15.17 Extracation Update 

6.14.17 Extraction Update

6.13.17 Extraction Update

6.12.17 Extraction Update

6.9.17 Extraction Update

6.8.17 Extraction Update

6.6.17 Extraction Update

6.4.17 Extraction Update

6.2.17 Extraction Update

6.1.17 Extraction Update

5.31.17 Extraction Update

5.30.17 Extraction Update

5.29.17 Natural Gas Extraction FAQ

5.29.17 Natural Gas Extraction Update

5.26.17 Health FAQ

5.25.17 Natural Gas Extraction Information

5.24.17 Natural Gas Leak Information / Update

5.19.17 Natural Gas Safety Information


Residents have seen an unrelated SoCalGas project on Lemon at Archibald that began several months ago to replace an old main line. This replacement was completed on June 1, 2017 and the new main line is fully operational.

The City has been notified, as a proactive precaution, SoCalGas will begin replacement of 2,200 ft of main line on northbound Archibald north of La Gloria in the coming weeks.


SoCalGas Call Center: (800) 427-2200, 24 hours a day, seven days a week.

SoCalGas Company Incident information:

AQMD Public Hotline: (800)Cut-Smog – (800) 288-7664

AQMD Online Complaint Form:

CPUC Public Safety Hotline: (800) 755-1447; press 3

CPUC Online Complaint Form:

SoCalGas Franchise Agreement (documents retrieved from 1978 microfilm)

What is natural gas?

Natural gas is used extensively in residential, commercial and industrial applications. It is the dominant energy used for home heating with slightly more than one half of American homes using gas. Natural gas is composed primarily of methane, but may also contain small amounts of chemical contaminants (e.g., ethane, propane, butane, benzene). In its original state, natural gas is odorless; however, distribution companies add mercaptans as an odorant (described as rotten cabbage/egg) to make it detectable in the event of leaks or uncontrolled releases. 

What are the potential health effects?

Methane, the main component of natural gas, is primarily an asphyxiant; which means, at high concentrations it can displace the oxygen you need for breathing. However, this is generally not of concern when exposures occur in typical indoor spaces (e.g., homes) or outdoors. Methane is currently not on the California Toxic Air Contaminants list or the California Prop 65 list (chemicals known to cause cancer, birth defects or other reproductive harm). At high exposures, methane can cause headache, dizziness, weakness, nausea, vomiting, and loss of coordination.

Mercaptans which creates a noxious odor, can be detected by the nose at very low concentrations, may cause irritation of the eyes, nose, and throat, and shortness of breath, nausea, headache, and dizziness.

Some of the naturally occurring contaminants that make up natural gas (e.g., ethane, propane, butane, benzene) can be toxic; however, are typically found at low levels when compared to the overall composition of natural gas (methane), and generally do not present an acute health hazard.

Following the recent Aliso Canyon gas leak that occurred in the north county of Los Angeles, the California Office of Environmental Health Hazard Assessment (OEHHA) conducted an evaluation of the potential health impacts of emissions from the gas leak to the Porter Ranch neighborhood. In general, OEHHA concluded that the symptoms reported by many Porter Ranch can be attributed to the odorants (mercaptans) in the natural gas. Additionally, air sample data did not indicate that an acute or chromic health hazard exists or increased cancer risk exists from any of chemicals measured. Findings of their evaluation can be found at:

Residents should contact their physicians if they are concerned with or experiencing any serious health effects. Additional information on the health effects of natural gas and its additives can be found in the links noted below.

What is the recent natural gas leak and what is being done to address the issue?

A natural gas leak in the Alta Loma area of Rancho Cucamonga; specifically Jadeite Avenue and La Gloria (west of Archibald) was identified. The leak was reported to Southern California Gas Co. by local residents on May 8, 2017. The source of the leak was identified and repaired by Southern California Gas Co. on May 9th. Efforts for removal of the gas that had leaked into the soil are continuing at this time. The City was notified about the leak on May 11, 2017, however, was not notified of the soil remediation efforts for another week.

South Coast Air Quality Management District (SCAQMD) was contacted on May 18, 2017 of the incident. SCAQMD inspectors were dispatched the same day, and began collecting readings with field instruments. SCAQMD continues to assess this situation and gather monitoring data. Air monitoring results and findings can be found on the SCAQMD website (