Alternatives for Managing the Nation's Complex Contaminated Groundwater Sites (2013) / Chapter Skim
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2 Magnitude of the Problem
2 Magnitude of the Problem
Pages 37-74
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From page 37... ...
NUMBER OF U.S. HAZARDOUS WASTE SITES The Committee sought the following types of information to assess the magnitude of the nation's hazardous waste problem: 1 The Safe Drinking Water Act defines public water systems as consisting of community water supply systems; transient, non-community water supply systems; and non-transient, non-community water supply systems -- all of which can range in size from those that serve as few as 25 people to those that serve several million.
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From page 38... ...
Second, there are differences in accounting across the programs that make it difficult to assess the magnitude of the hazardous waste problem on a consistent basis. In particular, CERCLA and RCRA's best available data are for facilities that could and often do contain many individual contaminated sites.
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From page 39... ...
The Installation Restoration Program (IRP) , which addresses toxic and radioactive wastes as well as building demolition and debris removal, is responsible for 3,486 installations containing over 29,000 contaminated sites at active, Base Relocation and Closure (BRAC)
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From page 40... ...
Indeed, at least 62 percent of the Installation Restoration Program sites that have achieved response complete (14,302 sites) did so without reporting a remedy in place (Deborah Morefield, DoD, personal communication, January 2011)
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From page 41... ...
These sites may be subject to land use restrictions, periodic reviews, monitoring, and/or maintenance. Thus, the known number of DoD Installation Restoration Program sites with residual contamination in place is 4,329 (2,931 + 1,398)
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From page 42... ...
, which is periodically updated to reflect facilities with the highest priority hazardous waste sites.3 The remedial actions at most nongovernmental CERCLA facilities are implemented by potentially responsible parties (PRPs) through legally enforceable administrative orders or settlement agreements, with EPA being the main agency responsible for enforcing the program.
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From page 43... ...
Reuse Site Reuse/Redevelopment Information on how the CERCLA program is working with communities and other partners to return hazardous waste sites to safe and productive use without adversely affecting the remedy. SOURCE: Adapted from http://www.epa.gov/superfund/cleanup/index.htm.
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From page 44... ...
According to the Superfund National Accomplishments Summary Fiscal Year 2010 (http://www.epa.gov/superfund/ accomp/numbers10.html) , the program has controlled potential or actual exposure risk to humans at 1,338 NPL facilities and has controlled the migration of contaminated groundwater at 1,030 NPL facilities.
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From page 45... ...
the human exposures environmental indicator "ensures that people near a particular site are not exposed to unacceptable levels of contaminants," and (2) the groundwater environmental indicator "ensures that contaminated groundwater does not spread and further contaminate groundwater resources."4 These indicators have now been satisfied at most of the highest-priority sites (see Table 2-5)
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From page 46... ...
Multiple hazardous waste sites, designated as solid waste management units (SWMUs) , may exist inside RCRA facilities, but numbers of SWMUs are not compiled by EPA headquarters.
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From page 47... ...
DOE's Environmental Management has historically been responsible for restoration at 134 installations that have about 10,000 release sites, although 21 installations were transferred to the U.S. Army Corps of Engineers in 2004 and one installation was added in 2001 (EPA, 2004)
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From page 48... ...
state voluntary cleanup programs and/or Brownfields sites. The mandated programs, which are roughly patterned after the CERCLA program, generally include enforcement authority and state funds to finance the remediation of waste sites.
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From page 49... ...
Dry Cleaner Sites Active and particularly former dry cleaner sites present a unique problem in hazardous waste management because of their ubiquitous nature in urban settings, the carcinogenic contaminants used in the dry cleaning process (primarily the chlorinated solvent PCE, although other solvents have been used) , and the potential for the contamination to reach receptors via the drinking water and indoor air (vapor intrusion)
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From page 50... ...
As of 2007, the on-site groundwater extraction system, which Table 2-6. However, dry cleaner sites are discussed here because of the high prevalence of active and inactive dry cleaner sites across the nation, their frequent proximity to residential neighborhoods, the highly recalcitrant and toxic nature of the contaminants released, and the importance of the vapor intrusion pathway.
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From page 51... ...
mulative statistics of remediation for these states provides an illustration of the state of progress in remediating U.S. dry cleaner sites (SCRD, 2010a)
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From page 52... ...
COST ESTIMATES In addition to tracking the number of hazardous waste sites that have not yet reached closure, the Committee sought information on the cleanup costs expended to date and cost estimates for reaching closure (including estimates for remediation efforts and for long-term management, within the next 30 to 50 years) for each of the programs discussed in the previous section.
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From page 53... ...
After ten years of remedial actions at such NPL facilities, states become fully responsible for continuing long-term remedial actions. 7 This total is based on an average cost per operable unit of $1.4 million for RI/FS, $1.4 million for remedial design, $11.9 million for remedial action, and $10.3 million for long-term remedial action (EPA, 2004)
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From page 54... ...
Most UST cleanup costs are paid by property owners, state and local governments, and special trust funds based on dedicated taxes, such as fuel taxes. Department of Energy To gain an understanding of the DOE costs that would be comparable to other federal programs, the Committee reviewed the Department's FY 2011 report to Congress, which shows that DOE's anticipated cost to complete remediation of soil and groundwater contamination ranges from $17.3 to $20.9 billion.
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From page 55... ...
. IMPACTS TO DRINKING WATER SUPPLIES The Committee sought information both on the number of hazardous waste sites that impact a drinking water aquifer -- that is, pose a substantial near-term risk to public water supply systems that use groundwater as a source.
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From page 56... ...
This suggests that 10 percent of NPL facilities adversely affect or significantly threaten drinking water supply systems. This estimate is further bolstered by EPA (2010b)
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From page 57... ...
Other Evidence That Hazardous Waste Sites Affect Water Supplies The U.S. Geological Survey (USGS)
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From page 58... ...
Trihalomethane (THM) Toluene 0 2 4 6 8 10 12 DETECTION FREQUENCY, IN PERCENT FIGURE 2-3 The 15 most frequently detected VOCs in public supply wells.
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From page 59... ...
Wells were sampled in 48 states in parts of 30 regionally extensive aquifers used for water supply. Aquifers were randomly selected for sampling and there was no prior knowledge of contamination.
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From page 60... ...
. Figure 2-4 withdraw water from shallower unconfined aquifers than from deeper confined aquifers.
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MAGNITUDE OF THE PROBLEM 61 FIGURE 2-5 VOCs and pesticides with detection frequencies of 1 percent or greater at assessment levels of 0.02 μg/L in public wells in samples collected from 1993–2007. SOURCE: Toccalino and Hopple (2010)
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From page 62... ...
Compared to the USGS data, this report gives a lower percentage of water supplies being contaminated: TCE concentration exceeded its MCL in 0.34 percent of the raw water samples from groundwater-derived drinking water supply systems. There are other potential sources of VOCs in groundwater beyond hazardous waste sites.
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From page 63... ...
It is no wonder that stakeholders are confused by the site closure metric, as operation and maintenance of a remedy may continue for many decades after "closure." To better understand the status of "closed" sites and whether these sites could in fact demand future resources for monitoring, reporting, or additional remediation, the Committee reviewed an Interstate Technology and Regulatory Council (ITRC) 9 survey of "closed" underground storage tanks, EPA cleanup success stories, and 80 facilities delisted from the NPL 9 The ITRC, which consists of states, federal agencies, industry, and other stakeholders, "develops guidance documents and training courses to meet the needs of both regulators and environmental consultants, and it works with state representatives to ensure that ITRC products and services have maximum impact among state environmental agencies and technology users" (http://www.irtcweb.org/aboutIRTC.asp)
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From page 64... ...
Of the remaining eight sites with contaminated groundwater, EPA's report states that only three sites were "able to achieve MCLs onsite" although two others achieved MCLs at an offsite point of compliance [see EPA (2009c) , Table D-1 in Appendix D]
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From page 65... ...
Of the 80, 45 had remedial objectives that specified a contaminant concentration goal for groundwater, either MCLs or some other level. For seven, the stated objectives involved some other specific metric (such as prevention of contaminated groundwater migration, exposure prevention, etc.)
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From page 66... ...
, suggesting that either there was no substantial groundwater contamination when the facility was added to the NPL or that natural attenuation occurred during the RI/FS process to significantly reduce contaminant concentrations. More interesting are the 20 facilities with contaminated groundwater that were deleted from the NPL where MCLs have not been met (as of August 2011 and as related in readily accessible EPA documents)
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From page 67... ...
The Army is conducting the five-year reviews, the second of which was completed in 2007. Site inspection shows that the remedies (for both contaminated groundwater and the landfill)
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From page 68... ...
The total does not include DoD sites that have reached remedy in place or response complete, although some such sites may indeed contain residual contamination. Finally, the total does not include sites that likely exist but have not yet been identified, such as dry cleaners or small chemical-intensive businesses (e.g., electroplating, furniture refinishing)
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From page 69... ...
No information is available on the total number of sites with contamination in place above levels allowing for unlimited use and unrestricted exposure, although the total is certainly greater than the number of sites tallied in Table 2-6. For the CERCLA program, many facilities have been delisted with contamination remaining in place at levels above unlimited use and unrestricted exposure (as much as half according to the Committee's analysis of 80 delisted NPL facilities with groundwater contamination)
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From page 70... ...
Surveys of groundwater quality report that 0.34 to 1 percent of raw water samples from wells used for drinking water (including public supply and private wells) contain mean VOC concentrations greater than the MCL, although there are no data linking these MCL exceedances to specific hazardous waste sites.
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From page 71... ...
Herman, Assistant Administrator, Office of En forcement and Compliance Assurance, and Elliot Laws, Assistant Administrator for Solid Waste and Emergency Response, to EPA Regions. Re: Coordination between RCRA Corrective Action and Closure and CERCLA Site Activities at 2 (September 24, 1996)
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From page 72... ...
2004. Cleaning up the Nation's Waste Sites: Markets and Technology Trends.
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From page 73... ...
:1539-1546. SCRD (State Coalition for the Remediation of Dry Cleaners)
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