In November 2002, EPA issued its Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soils (Subsurface Vapor Intrusion Guidance), 67 Fed. Reg. 71,169 (Draft Guidance). This document represented EPA’s first significant attempt to address concerns about vapor intrusion – the process whereby vapors emanating from contaminated subsurface soils or groundwater can make their way into buildings, either through natural pathways or building ventilation systems. Though methods for assessing the risk posed by vapor intrusion may still be inconsistent and unreliable, environmental scientists agree that the potential adverse effect on human health due to vapor intrusion may be significant. Thus, the need for some form of guidance on vapor intrusion by regulatory agencies was clear.
B. The Jurisdictional Conflict Between EPA and OSHA
1. EPA’s 2002 Draft Guidance and Its Aftermath
EPA’s 2002 Draft Guidance acknowledged the potential for conflict between EPA and OSHA authority where vapor intrusion in the workplace is concerned. EPA lacks explicit statutory authority to regulate vapor intrusion outright, thus the agency acknowledged that the Draft Guidance was just that – guidance on what EPA felt were appropriate requirements to address indoor air quality. Further, EPA noted that the Draft Guidance “[was] not expect[ed] to be used for settings that are primarily occupational.” Draft Guidance at 3. Thus, it was agreed that “OSHA [will] generally take the lead role in assessing occupational exposures.” Id. EPA’s position made sense, since it is OSHA and not EPA that generally promulgates regulations providing for worker safety (and has the expertise to do so).The reception the Draft Guidance received from regional EPA officials and, surprisingly, OSHA itself, was mixed. Regional EPA officials expressed their dissatisfaction with the Draft Guidance position and suggested that, since OSHA indoor air concentration levels are frequently more lenient than those of EPA, they would continue to push for EPA to take the lead role in regulating workplace air quality. Ultimately, environmental regulators at the state level began to weigh in and, depending on the state, either embraced the original Draft Guidance position or sided with regional EPA officials who pushed EPA to take a more active role. Meanwhile, OSHA officials have recently taken the position that, under Section 5(a)(1), the General Duty Clause of the Occupational Safety and Health Act (codified at 29 U.S.C. § 654), OSHA’s authority to regulate vapor intrusion is limited to only those instances in which the contamination originated from a chemical actually used in the workplace.
2. New EPA Draft Guidance
For the last few years, EPA has circulated a new Draft Guidance throughout federal agencies. While the document has not yet replaced the 2002 Guidance and is continually subject to change, the Draft Guidance at one point specified (and possibly still does specify) that EPA may impose its own environmental exposure standards in workplaces in a variety of circumstances. For example, the new Draft Guidance states that EPA may impose its own standards where workers are exposed to chemicals not used in the workplace. EPA may also impose its own standards where workers are exposed to chemicals used in a nearby workplace such as a mixed-use office park, medical facility, or manufacturing center. Again, however, the 2002 Draft Guidance remains EPA’s official guidance. Although EPA has been rumored to publicize the new Draft Guidance, such publication has not occurred.
3. OSHA, Not EPA, Has the Authority to Regulate Workplace Air Quality
a. Statutory and Administrative Law Arguments
Under the OSHA general duty clause, employers are required to “furnish to each employee, a place of employment free from recognized hazards causing or likely to cause serious physical harm.” This clause has long been interpreted to provide OSHA with the general authority to regulate the health and safety of workers in the workplace environment.
Environmental statutes such as the Resource Conservation and Recovery Act (RCRA) have recognized that, in situations where EPA may have a legitimate human health concern that also happens to impact the workplace environment, EPA has a duty to coordinate its efforts with OSHA – the government agency with the primary authority to regulate workplace safety.
Congress made the choice that EPA’s role regarding the protection of industrial workers should be to assist OSHA in enforcing existing standards rather than developing a separate set of standards. See United States v. Borowski, 977 F.2d 27, 31 (1st Cir. 1992) (explaining that RCRA exhibits explicit concern for industrial health by “requiring the EPA to provide information about employee hazards to the Secretary of Labor and OSHA for OSHA enforcement purposes”). When EPA tries to enforce its own standards for worker health, that action conflicts with RCRA’s requirement that EPA should act to assist OSHA.
In addition, any effort by EPA to contravene OSHA’s primary workplace authority would violate the Memorandum of Understanding (MOU) that has existed between the two agencies since 1990 and remains in effect. See “Memorandum of Understanding Between the U.S. Department of Labor, Occupational Safety and Health Administration and the U.S. Environmental Protection Agency,” Office of Enforcement (November 23, 1990).The MOU represents the agencies’ understanding regarding their respective general areas of responsibility and their agreement that OSHA, not EPA, has the authority to promulgate and enforce health and safety regulations for private sector workplaces. The MOU clarifies that EPA and OSHA have agreed to coordinate the activities of each agency with respect to potentially overlapping areas of jurisdiction, and that EPA will defer to OSHA on potential violations of OSHA standards that EPA may observe during EPA inspections. The document does not authorize or suggest that EPA may, at its discretion, establish more stringent standards for worker health than those established by OSHA.
b. Public Policy Arguments
In addition to the statutory authority granted to OSHA to regulate the workplace environment, a number of arguments counsel against EPA taking an active role in regulating workplace air quality. First, OSHA is better equipped to take into consideration the multitude of factors that go into the calculus of addressing worker safety. The industrial workplace environment is fundamentally different from that found in residential or public spaces. Industrial workers know they are working with volatile or potentially dangerous chemicals, and have received proper training in how to protect themselves. It is OSHA, not EPA, that has the expertise to mandate and oversee that training.
Moreover, industrial workers knowingly assume a risk of exposure and are equipped to protect themselves in ways that are wholly inapplicable to the general public. Workers, unlike the general public, receive a tangible benefit (employment compensation) that can be factored into the economic assessment of what constitutes acceptable exposure limits. Workers are exposed to chemicals over an eight-hour period, in the course of a work day – not on a 24-hour basis, as residents are in their homes. Workers are adults, and standards will necessarily be different than those in the home environment where children may be present.
These special workplace considerations are precisely the domain of OSHA, and it is OSHA that has the knowledge, expertise, and statutory authority to assess workplace environments and set standards accordingly. The mechanical systems in place that form the basis for the vapor pathways are already regulated according to OSHA standards. OSHA is the agency that considered all of these relevant factors in setting requirements and standards for the workplace environment. OSHA is the agency logically equipped to handle workplace vapor intrusion.
4. State Efforts to Resolve the Jurisdictional Conflict
Not surprisingly, a number of state-level environmental agencies have taken the initiative to develop their own policies and guidelines to address the risks posed by vapor intrusion. To date, various states have developed vapor intrusion policies that take different positions on the jurisdictional conflict. Of these, a handful of states have attempted to separate the indoor workplace and environmental spheres, so as to make clear which policies ought to control where.
Some states, such as Minnesota, emphasize the distinction between industrial and nonindustrial occupational settings and recognize the importance of OSHA’s role in industrial settings. Minnesota’s Pollution Control Agency has developed its own vapor intrusion screening values that displace OSHA standards in nonindustrial occupational settings, but OSHA standards control at industrial sites.
Other states, such as California, have taken the position that OSHA standards are inappropriate for regulating vapor intrusion in the indoor workplace environment. Instead, California’s Department of Toxic Substances Control endorses a site-specific risk-based approach for evaluating vapor concentrations. Similarly, Illinois, which has a pending rulemaking on indoor air, determined that using OSHA numbers was inappropriate. Like California, Illinois has proposed its own risk-based methodology for industrial/commercial sites as part of its tiered program, called Tiered Approach to Corrective Action Objectives (TACO).
Both Colorado and Michigan have adopted multi-factor tests to determine whether a particular site should be governed by risk-based criteria or by workplace standards that take into account economic considerations. For example, the Colorado Department of Public Health and Environment’s Draft Indoor Air Guidance states that OSHA numbers will generally be used in cases where (1) workers have voluntarily accepted known risks of exposure; (2) the exposure concentrations meet OSHA standards; (3) reasonably safe controls exist to protect worker health; and (4) workers are informed of the environmental contamination. The Michigan Department of Environmental Quality describes a similar approach.
Multi-factor tests, while representing a welcome acknowledgement that the workplace environment is fundamentally different (and thus requires fundamentally different approaches) from the residential setting, are, however, likely to complicate site-specific inquiries, potentially encouraging protracted jurisdictional battles and ultimately resulting in the need for still further guidance. Consequently, other states have made an effort to avoid using multi-factor tests.
Finally, states such as Alaska and New Jersey have embraced the notion – also endorsed by OSHA and apparently by EPA in a 2008 Draft Guidance not yet officially released, that occupational regulatory limits for chemical concentrations in workplace air are only intended to apply to exposure to workplace chemicals. What this policy fails to acknowledge, however, is that it is entirely appropriate for occupational standards to be generally used in the workplace environment, because the occupational standard is specifically formulated to take into account the unique features of the workplace. To ignore the workplace aspect of the problem is to treat residences and industrial areas as though they were the same – an approach which simply defies common sense.
With respect to the jurisdictional conflict between EPA and OSHA, it is clear that OSHA is the administrative agency with the statutory authority and expertise to regulate the workplace. The workplace setting is undeniably different from other settings, requiring consideration of numerous factors only OSHA is equipped to address. Regardless of what level of exposure is ultimately found to be protective in the workplace, OSHA and not EPA is the agency best equipped to make that determination. Nonetheless, state environmental agencies have taken a variety of approaches to regulating vapor intrusion in occupational settings despite OSHA’s proper role as the workplace regulator. Some have rejected OSHA standards altogether and have developed their own standards, while others use multifactor tests to determine when OSHA standards apply, and still others use OSHA standards.
Vapor intrusion remains an important issue across the legal landscape because many questions remain, including the future of ASTM’s E2600-08 standard and whether vapor intrusion assessment will become part of Phase I assessments. In fact, several toxic tort cases dealing with vapor intrusion are currently proceeding. These cases, together with the ASTM standards, will have an impact on prospective purchasers and current owners as they decide whether and to what extent they should investigate and attempt to mitigate vapor intrusion to improve indoor workplace air quality.
NOTICE TO READER: The preceding article provided updated information relating to the articles “Indoor Air Quality at Industrial Facilities with RCRA Corrective Action: Do EPA or OSHA Standards Apply?” (published Spring 2002) and “EPA/OSHA Jurisdictional Conflict Still Unresolved” (published October 1, 2006).
 Minnesota also recommends that Tier 1 vapor intrusion screening be conducted concurrently with a Phase I assessment.