Deliberate and accidental releases of poisonous hydrogen sulfide H2S from oil and gas installations have left an ever-wider trail of injuries, emergency evacuations, livestock deaths, and fear across northern Michigan. The findings result from an investigation by the Michigan Land Use Institute and the Human Health & Safety Committee.

The H2S releases documented thus far occurred between 1980 and 1997 in a 20-mile stretch in Manistee and Mason counties. Many never were officially recorded or thoroughly reviewed by either the oil and gas industry or state regulators. These releases represent a significant public health problem that essentially has been ignored by state authorities.

Hydrogen sulfide is routinely brought to the surface from wells drilled into the mile-deep, energy-bearing Niagaran Salina formation. The formation runs in a diagonal strip across the northern Lower Peninsula. Hydrogen sulfide, a common byproduct of oil and gas development, is an explosive gas, similar in toxicity to cyanide, that attacks the nervous system. Recognizable in trace amounts by its distinctive rotten egg odor and often referred to as "sour gas," it can be lethal.

The so-called "safe" exposure limits for hydrogen sulfide are based on the theoretical amount a healthy, 160-pound male worker could tolerate. The H2S occupational limit is 10 parts per million (ppm) over a normal 8-hour work day. In the real world, people do not react uniformly to H2S. Among the most vulnerable are adults with chronic illnesses, and children. Even someone with a cold has a weakened immune system, and consequently a lower tolerance for H2S exposure.

Jim Bedford, the acting chief of the Division of Environmental Epidemiology at the Michigan Department of Community Health, recommends an exposure limit guideline for the general population of 0.1 ppm, although no standard is yet in place. In comparison, California has a recommended public exposure limit of 0.03 ppm, and Alberta recommends a limit of 0.02 ppm. Even at these levels, however, some people can experience headaches and other symptoms of H2S poisoning.

Serious Accidents

Long a source of concern due to its toxic properties, H2S is attracting even more attention since an accident last summer in Manistee Township caused 11 people to be rushed to the hospital. The accident occurred after a cloud of hydrogen sulfide, intentionally released by a work crew during a maintenance procedure, drifted from a gas well into nearby businesses.

The research by the Institute and the H2S Committee found that the Manistee Township accident was not an isolated event:

* Since 1994, at least 22 people, four of them children, have been seriously injured during four H2S releases in Manistee and Mason counties. All of these people required hospital treatment.

* Since 1980, at least 10 separate accidental releases of H2S are known and caused at least 262 people in Manistee and Mason counties to evacuate their homes. Five of the accidents occurred since 1995.

* Since 1994, releases of H2S from pipelines and processing plants have killed at least 35 head of cattle in Mason County.

Given the documented health effects of H2S releases in Manistee and Mason counties, the installation of a pipeline from Oceana to Manistee that will carry at least 20,000 ppm H2S should give state officials reason to take a much harder look at what is occurring here. A major failure in this pipeline could cause a calamity.

Although the circumstances of each H2S release are different, a central fact is common to all: official indifference. An energy company was cited and penalized by state authorities in just one of the accidents.

The Comprehensive Plan

This comprehensive plan represents the work of local leaders, legal and technical experts, and citizens who in some cases have lived for years with the threat of H2S in their neighborhoods. It outlines the reasons for the increasing risk to the public from oilfield installations that contain H2S, and sets out a number of solutions.

The comprehensive plan also describes the need for new health-based research, and air dispersion models so that state regulators have a much firmer scientific foundation to determine risks and make regulatory decisions about H2S installations^.

And we found flaws in how agencies relate to each other on this issue. Essentially, they don't. Jurisdiction for facilities, wells, and pipelines that contain H2S is fragmented, and thinly spread across four agencies of state government.

In some cases, state agencies have no oversight for health and safety. Some rural pipelines, for instance, are essentially unregulated by the Michigan Public Service Commission. Until June, the Department of Environmental Quality said it had no jurisdiction for health and safety when reviewing new drilling permit applications.

In other cases, key pieces of information have been denied to citizens and local leaders. Last January, for instance, some Filer Township citizens were forced to evacuate after H2S was released from a new well being drilled in a neighborhood. When citizens and local emergency response chiefs wanted to know the quantities of H2S that were released and the causes of the accident, they were told by a state inspector that such information is privileged. State law allows companies to maintain a 90-day confidentiality period for all data.

Recommendation

After careful consideration we make the following workable, useful, and cost effective recommendations for ending this public health problem:

* In order to establish an effective system for managing oil and gas operations, and to protect the health and safety of citizens, there has to be consistency and uniformity among the agencies. An interagency task force should immediately be formed to develop a coordinated oversight framework for oil and gas development. Health and safety standards must be uniform and consistent. The public should be invited to participate on the task force.

* The evaluation of health hazards to the general public should become an integral part of the siting, permitting and regulating functions served by DEQ with respect to the oil and gas industry in Michigan. To do so in a credible and responsible fashion, the assessment of health hazards should be based on the best of medical and engineering technology.

*The public exposure limit must be based on the Department of Community Health general ecommendation for hazardous emissions, which takes 1/100 of the occupational limit as acceptable for a public exposure limit. This would be 0.1 ppm for hydrogen sulfide and takes into account the very young, individuals of average and poor health, the elderly, and the infirm. If wells pipelines or processing facilities can not meet this standard, they should not be allowed. *The Michigan Public Service Commission should develop a binding agreement with the DEQ that also includes a role for the Air Quality Division in evaluating the siting of pipelines that contain H2S.