An Analysis of 1,076 Spills in Oakland, California

that were reported to the

Emergency Response Notification System

from 1987 - 1996

Prepared by:

The NICHE Project
West Oakland Pilot Program

Table of Contents

1.0 Introduction
2.0 Methodology
3.0 Results
4.0 Data Sources

Table 1 - Annual Summary Reports
Table 2 - Location Summary Reports

Exhibit 1 - Sample ERNS Report
Exhibit 2 - Data Analysis Categories
Exhibit 3 - Spills Reported to ERNS
Exhibit 4 - Spills Involving Injuries
Exhibit 5 - Spilled Substances Reported to ERNS
Exhibit 6 - Chemical Substances Spilled
Exhibit 7 - Spill Locations
Exhibit 8 - Spill Causes


The NICHE Project prepared this analysis of Emergency Response Notification System (ERNS) records for Oakland, California. The NICHE Project ERNS data analysis included 1076 spill records that were made during a ten year period from 1987 to 1996. The ERNS database contains initial records of spills reported to federal agencies. This data analysis did not consider spills reported only to local and state regulatory agencies.

The NICHE Project evaluated these records based on the spill location, the cause of the spill, and the substances released. The analysis is part of the NICHE Project's West Oakland Pilot Program and includes the development of a comprehensive information database on neighborhood environmental risks. Half of the ERNS records were located in the area targeted by the NICHE Project's West Oakland Pilot Program.

The NICHE database will be used to support the Defensible Space Assessment, a community emergency preparedness training program. The results of the data analysis support the need for community training with over 50 percent of the spill events reported by someone other than the responsible party.

The remainder of this report is divided into three sections. A description of how the data analysis was performed is included in section 2.0. The results of the NICHE Project data analysis are presented in Section 3.0. More information on the ERNS database and the limitations of ERNS data is discussed in Section 4.0.

The NICHE Project West Oakland Pilot Program is sponsored by the African American Development Association, a community-based non-profit organization. Clearwater Revival Company, a local environmental engineering practice is providing technical support to the West Oakland Pilot Program.


The data analysis was performed as a four step process that included data collection, data extraction, data qualification and data labeling. Each of these four steps is further described below:

Step 1: Data Collection

Data was downloaded from the RTK Network's website on August 8, and August 11, 1997. A search for all ERNS records in the City of Oakland was made for each year (1987-96) that data were available. The information comprised of 1,076 separate records. The 1996 records appear to include ERNS reports made during the first six months of the year only.

The following is a sample of one of the 1,076 records that was downloaded:


2.2 Data Extraction

The ERNS data records were downloaded from the RTK Network's internet site as a text file. A computer program was used to extract data from six of the 19 data fields in each ERNS record. The extracted data fields included the date, address, site name, spilled substance, water way affected and description. The computer program removed text formatting and placed the data fields into a spreadsheet file.

2.3 Data Qualification

The spreadsheet file was sorted by date to enable tagging of duplicate records (spill reported on the same or consecutive dates at the same location). Records were individually reviewed to tag spills located outside of Oakland. In addition, spills that reported public concerns over storage of materials (no spill indicated) were tagged as null records. Data qualification resulted in the removal of 106 duplicate records, 6 out of bound records, and 5 null records.

2.4 Data Labeling

Each of the 963 qualified data records was labeled by location, cause and substance spilled. A description of the label categories used during the analysis are included as Exhibit 2. The 963 labeled data records are summarized in Appendix A. The date of the spill can be used to reference the complete ERNS reports included in Appendix B.


Table 1 provides the statistical summary of the location and cause for each ERNS report. Results are summarized for each year and for the entire period from 1987-96. Data for each location was also categorized by cause and by spilled substance. Results of this data analysis are summarized for each location and for all locations. This data summary is shown in Table 2.


The frequency of ERNS reports is approximately 96 per year. The most spills reported in a year is 149 in 1992, and the lowest is 44, reported in 1996. Exhibit 3 summarizes the frequency of spills from 1987 to 1996.
EXHIBIT 3 - Spills Reported to ERNS

Approximately two events per year result in an injury requiring a hospital visit. The most injury-related incidents occurred during 1992 when a total of five spills injured 24 people. No injury-related spills were reported to ERNS during either 1987 or 1995.

Exhibit 4 - Spills Involving Injuries
The most people injured during a single year was 36 in 1994. In one of three 1994 ERNS incidents, 33 individuals were sent to the hospital for decontamination after a firearm was discharged into an electrical transformer causing it to explode and spray transformer oil.

No spill incidents reportedly resulted in death. However, one ERNS incident did involve the removal of poisons from the scene of a suspected suicide.


The substances involved in ERNS were placed into nine separate categories as shown in Exhibit 5. The most common spilled substance was petroleum products accounting for 391 of the total 963 reports. The remaining categories included chemical (231), unknown (154), waste (67), paint (50), gas (42), asbestos (17), sewage (7), and radioactive material (4).

EXHIBIT 5 - Spilled Substances Reported to ERNS
Details on the substances categorized as chemicals, gas, radioactive and asbestos is provided in Exhibit 6.

The most common substance spilled is transformer and PCB oils comprising 21 of the 233 chemical spill events. Nine of the 21 incidents involving PCBs and transformer oil were reported due to a unique event, the 1991 Oakland Hills fire. However, even discounting the ERNS spill reports resulting from the Oakland Hills fire, transformer and PCB oil remains the most common spilled chemical substance (12 incidents). This result is consistent with an EPA review of their ARIP database (Accidental Release Prevention Requirements: Risk Management [Federal Register: March 13, 1995]) which indicated a large number of accidental releases from the electric utility industry. Although there were a high number of releases reported by electric utilities, the EPA noted that only about 2 percent of the industry accounted for the reported releases.

Asbestos was reported as a spilled substance in 17 incidents. Drug lab wastes also accounted for a relatively large number of ERNS reports (11 incidents). These incidents were generally a result of illegal dumping.

Chemicals used by the plating industry such as acids and cyanide combined, accounted for over 30 of the total chemical incidents (13%). The ERNS records for one facility, Francis Plating, show a history of releases due to violations of pollution prevention laws that culminated in a fire which caused evacuations of several hundred people. In 1993 alone, another plating facility, Jerry's Plating, had three ERNS incidents (illegal dumping, using hazardous materials for cleaning a floor, and an employee falling into a tank of acid).

A relatively large number of incidents (9) involved chemicals used to make polyurethane foam (toluene 2,4,-diisocyanate, diphenyl methane diisocyanate).

The 43 incidents involving gases included liquefied petroleum gas (14 incidents), ammonia (11 incidents), and chlorine (6 incidents). Both ammonia and chlorine are acutely toxic gases.

Though it is the least common of the spilled substances, radioactive material is a concern. The most serious incident, described in Exhibit 1, involved a leaking container of radioactive material. Two incidents involve the theft of radioactive material and the third involves the illegal dumping of a cylinder commonly used by hospitals to hold radioactive materials.


As shown in Exhibit 7, approximately 2.3 percent of the ERNS reports did not have an adequate site address to assign a location. A larger number of spills were reported in the water (121 of 963 or 12.6%). The remaining 820 spills were divided between the NICHE Project West Oakland Pilot Program area (475/820 or 58%), the remainder of Oakland (270/820 or 33%) and the highways (75/820 or 9%). The NICHE West Oakland Pilot area includes the residential/industrial area west of Telegraph Avenue as well as the Oakland Army Base, Naval Supply Center, Port of Oakland, and Union Pacific Railyard.

EXHIBIT 7 - Spill Locations
Within the West Oakland Pilot Program area 35 percent of the spills occurred in the mixed industrial/residential land use area, 31 percent of the spills were reported on Port of Oakland property, and 22 percent in Union Pacific Railroad property. The remainder was reported by the US Navy and US Army (11 percent combined).


As shown in Exhibit 8 the most common cause of an ERNS report is illegal dumping which accounts for about one in four reports. Illegal dumping is the number one cause of ERNS reports in West Oakland and the remainder of Oakland.

EXHIBIT 8 - Spill Causes
Freight accounted for 17 percent of the total accidents and was responsible for the majority of the spills at the Union Pacific Railyard, was the number two cause of spills at the Port of Oakland and on the Highway system and third most common cause of spills in West Oakland.

Public Observation also accounted for approximately 17 percent of the total ERNS reports. Public observations of off-shore oil sheens at Lake Merritt, the Oakland Estuary, Port of Oakland, and Naval Supply center accounted for 86% of the spills reported to ERNS by the public.

Spills caused by human error out pace spills caused by equipment failure by a ratio of three-to-two. Together these two causes account for 17.5 percent of the ERNS reports. Hazardous material regulations (spill prevention, risk management) are primarily designed to prevent these incidents involving human error and equipment failure. The NICHE Project analysis indicates that these two causes account for only one in six hazardous material incidents.

Marine Vessels (9 percent of the total) caused more spills than truck and rail traffic accidents combined (7.5 percent). Marine vessel accidents were the number one cause of ERNS reports at the Port of Oakland, Naval Supply Center and Oakland Army Base. Traffic accidents were the number one cause of an ERNS report on the Highway system and number two cause at the Union Pacific Railyard.

Fires, fumes, and buried utilities each account for 2 to 3 percent of the reported ERNS incidents.


4.1 RTK Network

RTK NET was started in 1989 in support of the Emergency Planning and Community Right to Know Act (EPCRA), which mandated public access to the Toxic Release Inventory. It is operated by two nonprofit organizations--OMB Watch and The Unison Institute--and funded by various government agencies and foundations.

RTK NET was established in order to empower citizen involvement in community and government decision-making. RTK NET provides access to government databases and lets you search them for free. RTK NET has many databases on the environment. You can access RTK NET via the web (, bbs, or telnet. RTK NET can be reached at:

Right-to-Know Network
1742 Connecticut Avenue, NW
Washington, DC 20009
Phone: 202/234-8494
Fax: 202/234-8584

4.2 ERNS Database

The ERNS is a nationwide, centralized database supported by EPA, the US Coast Guard (USCG) and the Department of Transportation (DOT) and maintained by the Transportation Systems Center (TSC). This information-sharing network documents every release notification received by the National Response Center, EPA Headquarters and Regional offices and the USCG.

ERNS is a documenting system not a tracking system. Only the initial notification of the release is documented, not the actions performed on the site. ERNS contains information on every reported release (including release of non-hazardous substances and releases below reporting quantity levels), not only those that result in removal actions. ERNS also provides assistance to regional enforcement personnel in supporting day-to-day response operations and enforcing release reporting requirements.

Exhibit 9 provides a diagrammatic representation of the ERNS Release notification process. Responsible parties, private citizens, or State or local officials may report a release to the NRC. The NRC documents the notification and relays the data to the appropriate On-Scene Coordinator (OSC) for a response determination. In the event that EPA or USCG is the first to be notified, the notified agency will document the release incident data

and relay the information to the appropriate OSC for response determination. When an EPA Region is the notified agency, the release data must be transferred within two weeks of receipt to the RCS for input into the NRC database.

To ensure the efficient functioning of ERNS, EPA regions and USCG field offices are responsible for:

EPA headquarters, in conjunction with USCG and DOT, are responsible for providing overall direction and guidance on the development and operation of ERNS. ERNS has been fully operational since October 1987.

The ERNS data is maintained by the US EPA. Further information on the database can be obtained from:

Office of Emergency and Remedial Response
Mail Code 5202G
401 M Street, S.W.
Washington, DC 20460
(202) 260-2342


The EPA warns to be aware of the following factors which can affect the quality of ERNS data:

  1. Completeness and accuracy: ERNS primarily contains initial accounts of releases, made during or immediately after an incident, when exact details are often unknown. These data are usually not updated unless an EPA Region is involved in the response action.

  2. Multiple notifications: Because the data are gathered from many sources, multiple notifications of some releases may exist. These may or may not be exact duplicates. Large releases, in particular, are prone to multiple notifications.

  3. Multiple sources: ERNS contains data from multiple sources (i.e., the NRC, the EPA Regions, and the USCG). Each agency has a slightly different mission and distinct data gathering requirements.

  4. Data updates: This database is updated regularly. Therefore, downloaded data may be changed by future updates.

  5. Data entry errors: Data in ERNS are generally reported over the telephone. Data inconsistencies should be investigated to ensure that they are not the result of data entry mistakes.

  6. Data structure changes: System upgrades, which include field additions and other database structure changes, have been made to improve data quality. However, structure changes that occur after a report is received, may make the report appear incomplete. Care must be taken when working with data that span several years.

  7. Unique events: Infrequent, unusual releases may affect statistical results. A release notification that grossly affects overall results should be examined further.

The EPA states that ERNS data are best used for:

Statistical analyses of large data sets: The effects of data inconsistency are diminished within large data sets because individual records are less likely to skew results.

Retrieving information about a specific release notification: Data inconsistencies are irrelevant when analyzing individual reports.

The EPA states that the following uses of ERNS Data be avoided:

Statistical analyses of small data sets, such as notifications from a single township over a short time span. Compared with the effects on a large data set, an incorrect record has more weight in a small data set and may skew the results.

The sole source of information about a release. All information in ERNS should be checked against as many other sources as possible.


Data limitations were recognized during this statistical study. Data qualification resulted in the removal of 113 mostly duplicate data records greatly reducing the limitations of the qualified data set.

Data entry errors are believed to exist within the data set due to inconsistent data fields (i.e. asbestos spill described as 500 to 1000 gallons per hour). Due to the large volume of data that was analyzed it is likely that the effect of data entry errors would be minimized.

The only unique event that appeared to impact data results of this analysis was the Oakland Hills fire in 1991. This single event was responsible for 40 percent of the releases caused by fire and for 43 percent of the releases of transformer oil/PCBs (43%).

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