WASHINGTON, D.C. 20460
                                     SEP i 9
                                                                              OFFICE OF
                                                                            SOLID WASTE AND
                                                                          EMERGENCY RESPONSE
                                                                   OSWER Directive #9355.5-32
Clarification of OSWER's 1995 Technical Impracticability Waiver Policy-

James E. Woolford, Director  Jf~~
Office of Superfund Remediation and Technology Innovation

             Reggie Cheatham, Acting Director  /
             Federal Facilities Restoration and Reuse Office

TO:         Superfund National Policy Managers. Regions 1-10


The purpose of this memorandum is to provide clarification to the 1995 Office of Solid Waste and
Emergency Response (OSWER) memorandum entitled. Superfund Groundwater RODs: Implementing
Change This Fiscal Year, July 31, 1995, (OSWER Directive 9335.3-03 P) regarding the use of Technical
Impracticability (TI) waivers at Comprehensive Environmental Response Compensation and Liability
Act (CERCLA) sites with Dense Non-Aqueous Phase Liquid (DNAPL) contamination.

The 1995 memorandum did modify the existing Guidance for Evaluating the Technical Impracticability
of Ground-Water Restoration. September 1993, (OSWER Directive 9234.2-25), by expecting each
region to employ a Tl waiver for sites with DNAPL contamination and to include written justification of
the  Tl waiver in the Fiscal Year 1995 remedy decision document (e.g.. ROD). This is to clarify that: 1)
the  1995 memorandum was intended to apply only to remedy decisions made in Fiscal Year 1995 and 2)
DNAPL contamination in and of itself should not be the sole basis for considering the use of a TI waiver
at any given site.

Improvements in science and technology have shown much progress in characterizing and successfully
treating/extracting DNAPLs from subsurface areas. Recent remedy decisions have selected a variety of
in-situ technologies to address DNAPL contamination such as in-situ chemical oxidation, in-situ
bioremediation and in-situ thermal remediation. We recommend that regional offices continue to refer
to the 1993 TI Guidance (see hup: . w\\A\.cpa.ijo\ superrundliealth/conmedia/gwdocs/techimp.htm)
when evaluating whether a TI waiver may be appropriate at a site.  Regions are reminded that even when
applicable or relevant and appropriate requirements (ARARs) are waived at a Superfund site due to TI,
the NCP states that EPA's general expectations are to prevent further migration of the contaminated
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groundwater plume, prevent exposure to the contaminated groundwater and evaluate risk reduction
measures as appropriate (see CFR 300.430(a)(l)(iii)(F)). In addition, CERCLA Section 121's
requirement to select remedies that are protective of human health and the environment is separate and
independent from the statute's requirement to comply with ARARs. Thus, even where an ARAR is
waived pursuant to CERCLA Section 121(d)(4), the remedy must still be protective of human health and
the environment.


Consistent with CERCLA and the NCP, the Superfund remedial and federal facilities programs remain
committed to restoring groundwater to beneficial use at NPL sites.  Furthermore, consistent with the
Government Performance and Results Act (GPRA), our programs seek to bring human exposures under
control as quickly as possible. In situations where groundwater restoration is unattainable from an
engineering perspective, considering a TI waiver may be an appropriate part of the remedy selection
process. Regions generally should not consider the mere presence of DNAPL alone but should provide a
sufficient, science-based justification for invoking a TI waiver. Regions should continue to consider up-
to-date information available  from OSWER's Technology Innovation and Field Services Division
(TIFSD) and other current knowledge of potential DNAPL remediation techniques when evaluating
alternatives and making CERCLA response decisions.

Since DNAPL remedies are included as part of response actions for both federal facilities and non-federal
sites, CERCLA Section 120(a)(2) provides that all guidelines, rules, regulations, and criteria for preliminary
assessments, site investigations, National Priority List (NPL) listing and remedial actions are applicable to
federal facilities to the  same extent as they are applicable to other facilities.

For the reasons stated above, the  1995 memorandum entitled, Superfund Groundwater RODs:
Implementing Change  This Fiscal Year, July 31, 1995 (OSWER Directive 9335.3-03P) should no longer
be considered when making current site decisions.

Copies of this document are available on our web site
http://www.epa.gov/superfund/health/conmedia/gwdocs/htm. For further information on TI waivers for
CERCLA remedial actions, please contact Matt Charsky at charsky.matthewfojepa.gov or (703) 603-
8777 or Dave Bartenfelder at  bartenfelder.david@epa.gov or (703) 603-9047. For federal facilities
information, please contact your Federal Facilities Restoration and Reuse Office (FFRRO) Regional


cc:    Mathy Stanislas, OSWER
       Lisa Feldt, OSWER
       Barry Breen, OSWER
       David Lloyd, OSWER/OBLR
       Bridget Lowery, OSWER/CPA
       Suzanne Rudzinski, OSWER/ORCR
       Carolyn Hoskinson, OSWER/OUST
       Sue Priftis, OSWER/OPM

Lawrence Stanton, OSWER/OEM
Elliott Gilberg, OECA/OSRE
Dave Kling, OECA/FFEO
Mike Flyrrn, OAR/ORIA
Rick Linthurst, ORD/IOAA
John Michaud, OGC/SWERLO
Federal Facility Leadership Council Membership
Superfund Branch Chiefs, Regions 1-10
Superfund Branch Chiefs, Office of Regional Counsel. Regions 1-10
Chloe Melz, Superfund Lead Region Coordinator, US EPA Region 2
NARPM Co-Chairs
Federal Facility Forum Co-Chairs
Groundwater Forum Co-Chairs