United States General Accounting Office

GAO Report to the Chairman, Committee on

Small Business, U.S. Senate

July 1995 SUPERFUND

Information on Current

Health Risks

GAO/RCED-95-205

GAO United States

General Accounting Office

Washington, D.C. 20548

Resources, Community, and

Economic Development Division

B-261507 

July 19, 1995

The Honorable Christopher S. Bond

Chairman, Committee on Small Business

United States Senate

Dear Mr. Chairman:

Superfund cost estimates are growing at a substantial rate. The Superfund

program was authorized through 1994 at $15.2 billion, covering over 1,100

nonfederal sites on the National Priorities List (NPL).1

 These figures could

grow to $75 billion (in 1994 dollars) and 4,500 nonfederal sites, according

to the Congressional Budget Office (CBO).2

 Because of these escalating

costs, congressional decisionmakers want to know more about the human

health risks addressed by the program. Although the Administrator of the

Environmental Protection Agency (EPA) recently testified to the Congress

that approximately 73 million people live fewer than 4 miles from at least

one Superfund site, much debate has occurred about the extent to which

these sites pose health risks for cancer or other conditions, such as birth

defects or nerve or liver damage.

To help measure the health risks from Superfund sites, you asked us to

provide the best available information on (1) the extent to which sites may

pose health risks under current land uses, as opposed to the risks that may

develop if land uses change in the future; the nature of the current risks;

and the types of environmental media (e.g., groundwater, soil, or air) that

pose these risks and (2) whether EPA’s short-term response actions to

mitigate the health risks from Superfund sites have reduced the risks

under current land uses. This report presents our findings on these issues

as they relate to the 225 nonfederal NPL sites contained in EPA’s data base

on health risks from Superfund sites—the most comprehensive automated

information available as of early 1995. These sites constitute most of the

sites where EPA made cleanup decisions between 1991 and mid-1993. As

agreed with your office, in our ongoing work for you we will examine

other related issues, such as the nature of health risks from Superfund

sites under future changes in land use.

1

The Congress created the Superfund program under the Comprehensive Environmental Response,

Compensation, and Liability Act (CERCLA), which authorized the Environmental Protection Agency

(EPA), among other things, to clean up contamination at the nation’s hazardous waste sites. EPA

places the sites it considers to be the most severely contaminated on the NPL for cleanup.

2

The Total Costs of Cleaning Up Nonfederal Superfund Sites, CBO (Washington, D.C.: Jan. 1994).

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B-261507 

Results in Brief About one-third (or 71) of the 225 sites contained in EPA’s data base posed

health risks serious enough to warrant cleanup, given current land uses.3

About another one-half (or 119) of the 225 sites did not pose serious health

risks under current land uses but posed such health risks under EPA’s

projections about future changes in land use. The remainder of the sites

did not pose health risks serious enough to warrant cleanup action under

either current or future land uses. However, EPA may decide to clean up

these remaining sites to comply with other federal or state regulations or

because of a threat to the environment, such as contamination

endangering a wetland. The current health risks at the 71 sites usually

occurred through a single environmental medium, most commonly

groundwater or soil. Of these 71 sites, 28 percent posed cancer risks;

30 percent posed risks for noncancer conditions, such as birth defects or

nerve or liver damage; and the remainder posed risks for both cancer and

other, noncancer conditions.

According to officials from EPA’s Office of Emergency and Remedial

Response, EPA’s short-term response actions have temporarily mitigated

the health risks that could immediately endanger the population

surrounding the 71 sites that posed serious health risks under current land

uses. Under EPA’s policy, whenever a Superfund site poses such a health

risk, a short-term response, known as a “removal action,” will be

undertaken. EPA’s data indicate that various removal actions have occurred

at 31 of the 71 sites. EPA officials caution that while removal actions clearly

reduce health risks, information is not readily available to determine the

extent to which the removal actions taken at these 31 sites affected the

risks reported in the data base. The remaining 40 sites did not pose

immediate risks substantial enough to warrant removal actions, according

to the officials, although the sites still pose longer-term health risks under

current land uses. For example, at some sites contaminated groundwater

that does not immediately endanger surrounding populations may

eventually reach the drinking water supplies used by current residents,

thereby posing an eventual health risk.

Background With the enactment of CERCLA in 1980, the Congress created the

Superfund program authorizing EPA, among other things, to clean up

contamination at hazardous waste sites. CERCLA also created a trust fund

available for various cleanup activities and authorized EPA to compel the

3

EPA considers the risk serious enough to warrant cleanup if (1) an individual has more than a 1 in

10,000 chance of developing cancer from exposure to the site’s contaminants or (2) if exposure to the

site’s contaminants might exceed the level humans can tolerate without developing other ill health

effects, such as birth defects or nerve or liver damage.

Page 2 GAO/RCED-95-205 Information on Current Health Risks
B-261507 

parties responsible for these sites to help conduct or pay for the cleanup.

The Superfund program was extended in 1986 and in 1990 and is now

being considered for reauthorization. Under CERCLA, EPA assesses

contaminated areas and then places the sites it considers to be the most

highly contaminated on the NPL for further investigation and cleanup.

EPA responds to hazardous substances at Superfund sites through

“removal” and “remedial” actions. Removal actions are generally

short-term (less than 1 year), low-cost (under $2 million) measures

intended to address actual or potential releases of hazardous substances

that pose a threat to human health or the environment. Although many

removal actions are temporary measures to prevent exposure by

stabilizing conditions at a site or limiting access to the site, some removal

actions may permanently clean up contamination.4

 Typical removal

actions include installing security measures at a site, removing tanks or

drums of hazardous substances from a site, or excavating contaminated

soil. By contrast, remedial actions are long-term measures intended to

permanently mitigate the risks from a site. Typical remedial actions

include treating or containing contaminated soil, constructing

underground walls to control the movement of groundwater, and

incinerating hazardous wastes.

Once a site is on the NPL, EPA conducts a “remedial investigation” to

determine whether the nature and extent of the contamination at the site

warrant remedial action. One component of this investigation is a baseline

risk assessment to evaluate the health risks the site would pose if no

cleanup occurred.5

 For the baseline risk assessment, EPA evaluates health

risks under both “current land-use conditions” and “alternate future

land-use conditions.” As an example, a site would pose health risks under

current land-use conditions if local residents used groundwater containing

a hazardous level of contaminants from the site as drinking water or if

contaminated groundwater could eventually reach the wells of distant

residents. By contrast, a site would pose health risks under alternate

future land-use conditions if future land development would expose

people to health risks from the site’s contaminants, even if the site may not

pose risks under current land uses.

4

According to officials in EPA’s Office of Emergency and Remedial Response, while permanent

removal actions are preferred over temporary measures, EPA must consider several factors, including

competing needs at other sites, in determining the appropriate removal action for a site.

5

At some sites, EPA may take removal actions before the risk assessment occurs, which could reduce

somewhat the risk estimated in the baseline assessment of the site.

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B-261507 

At each site, EPA assesses the cancer risk, as well as the risk for other ill

health conditions (noncancer risk), posed by the contaminants in

groundwater, soil, surface water, sediment, air, and other environmental

media to determine if these risks warrant cleanup. In the case of cancer,

EPA considers the risk serious enough to warrant cleanup if the risk

assessment indicates more than a 1 in 10,000 probability that exposure to

the site’s contaminants may cause an individual to develop cancer. In the

case of noncancer health effects, such as birth defects or nerve or liver

damage, EPA considers the risk serious enough to warrant cleanup if the

risk assessment indicates that exposure to the site’s contaminants might

exceed the level that the human body can tolerate without developing ill

health effects.

EPA’s Responsive Electronic Link and Access Interface (RELAI) data base,

from which we drew information for this report, is the most

comprehensive and current automated source of EPA’s data on the health

risks of Superfund sites. Created in 1993, this data base contains

information about health risks from EPA’s risk assessments and other

documents related to 225 nonfederal sites, which constitute most of the

sites where EPA made cleanup decisions between 1991 and mid-1993.

One-Third of Sites

Posed Risks Under

Current Land Uses

About 32 percent (71) of the 225 sites in EPA’s data base posed serious

health risks under the land uses current at the time of the risk assessment.

About 53 percent (119) of the 225 sites did not pose risks warranting

cleanup under current land uses, but posed such risks under EPA’s

projections about future changes in land use.6

 The remaining 15 percent

(35) of the sites did not pose health risks serious enough to warrant

cleanup action under either current or future land uses. As we noted

earlier, EPA may still decide to clean up these remaining sites because of

federal or state regulations or because of a threat to the environment, such

as contamination endangering a wetland. Figure 1 summarizes the extent

of the health risks posed by the 225 sites.

6

According to EPA officials, the Superfund program is supposed to address significant health risks

under both current and future land uses. About 85 percent of sites in the RELAI data base meet EPA’s

criteria for serious health risk under either current or future land uses.

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B-261507 

Figure 1: Percentage of 225 Superfund

Sites With Risks Warranting Cleanup

Under Current or Future Land Uses

32% • Sites With Risks Under Current

Land Uses (71)

53%•

Sites With Risks Under Alternate

Future Land Uses Only (119)

•15%

Sites With Risks Not Warranting

Cleanup Action (35)

Note: Sites posing risks under current land uses are assumed to pose both current and future

risks.

Source: GAO’s analysis of data from EPA’s RELAI data base.

Our analysis of EPA’s data on the 71 sites posing health risks under current

land uses indicates the following:

• at 77 percent (55) of the sites, a single environmental medium, usually

groundwater or contaminated soil, posed the health risks and

• at the remaining 23 percent (16) of the sites, multiple environmental media

posed the health risks.

Figure 2 compares the environmental media posing health risks at the 71

sites under current land uses.

Page 5 GAO/RCED-95-205 Information on Current Health Risks
B-261507 

Figure 2: Environmental Media Posing

Health Risks Under Current Land Uses

at 71 Superfund Sites

Number of Sites

0

5

10

15

20

25

30

Groundwater

Soil

Sediment

Air

Surface Water

Multiple Media

Environmental Media Posing Health Risks

27

22

4

2

0

16

Source: GAO’s analysis of data from EPA’s RELAI data base.

EPA’s data for the 71 sites also indicate that 28 percent posed cancer risks,

30 percent posed noncancer risks, and 42 percent posed both cancer and

noncancer risks. EPA’s noncancer risk category includes such conditions as

birth defects or nerve or liver damage. Figure 3 compares EPA’s data on the

cancer and noncancer risks posed by the 71 Superfund sites.

Page 6 GAO/RCED-95-205 Information on Current Health Risks
B-261507 

Figure 3: Percentage of Sites Posing

Cancer or Noncancer Health Risks

Under Current Land Uses

28% • Sites Posing Cancer Risks (20)

30% • Sites Posing Noncancer Risks (21)

•42%

Sites Posing Both Cancer and

Noncancer Risks (30)

Source: GAO’s analysis of data from EPA’s RELAI data base.

Removal Actions

Have Reduced

Immediate Health

Risks

According to officials from the Office of Emergency and Remedial

Response (OERR), EPA’s removal program has mitigated the immediate

health risks from Superfund sites, at least temporarily. EPA’s policy

requires a short-term response whenever a Superfund site poses a health

risk that immediately endangers the surrounding populations. According

to the OERR officials, under the removal program EPA has periodically

evaluated the NPL sites and has taken intervening steps at those sites

determined to pose immediate threats to health. EPA’s data indicate that

removal actions have occurred at 31 of the 71 sites that posed risk under

current land uses. Figure 4 shows the various types of removal actions

taken at these 31 sites.

Page 7 GAO/RCED-95-205 Information on Current Health Risks
B-261507 

Figure 4: Removal Actions at 31

Superfund Sites Posing Immediate

Health Risks Under Current Land Uses

Number of Sites

0

5

10

15

20

Fence or Other

Security Provided

Contaminants Moved off Site

Contaminants Contained or Stored on Site

Contaminants

Treated on Site

Population Relocated

Water Provided

Other/Unknown

Type of Removal Action

19

18

16

4

2

1

4

Note: The total number of removal actions exceeds 31 because EPA has performed multiple

removal actions at some sites.

Source: GAO’s analysis of data from EPA’s RELAI data base.

OERR officials caution that while removal actions have mitigated the

immediate health risks at these sites, information is not readily available to

determine the extent to which removal actions have affected the health

risks reported in the data base. According to these officials, the available

information does not indicate whether the removal actions removed or

treated only enough contaminants to mitigate the risks that immediately

endangered a site’s surrounding population. For example, a small pile of

highly contaminated soil might have been removed, mitigating the

immediate risks to children playing nearby but having little effect on the

site’s more extensive soil contamination.

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B-261507 

OERR officials also caution that the available information does not indicate

the extent to which the health risks reported in the data base may already

reflect the effect of the removal actions. In some cases, a removal action

may have taken place before the risk assessment. OERR officials are

uncertain about whether, in such cases, risk assessors might have

considered the effect of the removal in reporting the site’s health risks.

Of the 71 sites posing risks under current land uses, 40 sites did not pose

immediate threats substantial enough to warrant removal actions,

according to OERR officials. These officials explained that although these

sites did not pose risks that immediately endanger nearby populations,

they still pose risks under current land-use conditions. For example,

according to these officials, at some sites contaminated groundwater has

not yet reached drinking water. However, under current land uses, the

groundwater could eventually reach a drinking water supply, thereby

posing a health risk. Table 1 categorizes these 40 sites by the

environmental media posing the current health risk.

Table 1: Forty Sites Posing Health

Risks Under Current Land Uses That

Have Not Warranted Removal Action

Environmental medium that posed health risks

Number of sites that have

not warranted removal

actions

Groundwater 18

Soil 13

Sediment 2

Air 1

Surface water 0

Multiple media 6

Total 40

Source: GAO’s analysis of data from EPA’s RELAI data base.

Agency Comments We requested that EPA provide comments on a draft of this report. On

June 19, 1995, we met with officials from EPA’s OERR, including the Chief,

Response Operations Branch, to obtain the agency’s comments on the

draft report. The officials told us that they were generally satisfied that the

information presented in the report is accurate. The officials provided

additional perspectives on several issues discussed in the report and also

suggested technical corrections on a few matters. We revised the draft

report to incorporate these comments.

Page 9 GAO/RCED-95-205 Information on Current Health Risks
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Scope and

Methodology

To provide information on the extent to which Superfund sites may pose

serious health risks under current land uses and on the nature of those

risks, we analyzed pertinent information from EPA’s most comprehensive

data base on the health risks from Superfund sites. While we did not

independently verify the accuracy of EPA’s data, we reviewed the agency’s

data collection and verification guidelines and internal quality assurance

procedures, and determined these internal controls to be adequate. We

worked closely with EPA officials to ensure a proper interpretation and

analysis of the data. Although the Agency for Toxic Substances and

Disease Registry—the Public Health Service agency responsible for

identifying health problems in the communities around Superfund

sites—also assesses sites’ health risks, we did not analyze the agency’s

evaluation data on Superfund sites for this report because of time

constraints.

To provide information on whether EPA’s short-term response actions have

reduced the health risks from Superfund sites, we obtained EPA’s data on

the removal actions that have occurred at the 71 sites where current health

risks existed. Although we did not verify this information, we discussed

the information and EPA’s removal policy and actions with officials from

OERR’s Response Standards and Criteria and Response Operations

branches.

We performed our work between April and June 1995 in accordance with

generally accepted government auditing standards.

As arranged with your office, unless you publicly announce this report’s

contents earlier, we plan no further distribution until 10 days after the date

of this letter. At that time, we will send copies to the Administrator, EPA;

the Director, Office of Management and Budget; and other interested

parties. We will also make copies available to others on request.

Page 10 GAO/RCED-95-205 Information on Current Health Risks
B-261507 

The major contributors to this report are listed in appendix I. If you or

your staff have any questions about this report, please call me at

(202) 512-6111.

Sincerely yours,

Peter F. Guerrero

Director, Environmental

 Protection Issues

Page 11 GAO/RCED-95-205 Information on Current Health Risks
Appendix I 

Major Contributors to This Report

Resources,

Community, and

Economic

Development Division,

Washington, D.C.

Eileen R. Larence, Assistant Director

Patricia J. Manthe, Evaluator-in-Charge

Karen A. Simpson, Evaluator

Barbara A. Johnson, Program Analyst

Jeanine M. Brady, Reports Analyst

Chicago Regional

Office

Sharon E. Butler, Senior Evaluator

(160287) Page 12 GAO/RCED-95-205 Information on Current Health Risks
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