HAZARDOUS WASTE MANAGEMENT 451
the EPA to inspect government and privately owned facilities
which handle hazardous waste.
Today the law is again being considered for revision, and
among the issues that are always under discussion include
“how clean is clean” when remediating industrial and landfill
sites. The cleanup standards are not consistent among state and
federal programs, frequently causing significant discussion
among responsible parties and regulators. At this time, risk
assessments are used more often in an effort to design remedial
programs that are appropriate for the media, and the resources
being protected. A risk assessment might provide, for example,
the necessary information to set differing groundwater cleanup
goals in a sole source aquifer, than in an industrialized area sit-
uated above a brackish water-bearing zone where the ground-
water will not again be used for potable purposes.
With the preceding paragraphs as general background,
the brief discussion which follows on hazardous wastes
emphasizes some of the technologies that have been suc-
cessfully used for the treatment and disposal of hazardous
wastes, and remediation of contaminated properties.HAZARDOUS WASTE DEFINEDHazardous wastes encompass a wide variety of materials. In
1987, the US EPA estimated that approximately 238 million
tons could be classified as hazardous. This number is probably
generous but suffice it to say that a great deal of material of a
hazardous and dangerous nature is generated and disposed of
every year.
The Resource Conservation and Recovery Act defines a
hazardous waste as a solid waste that may cause or signifi-
cantly contribute to serious health or death, or that poses a
substantial threat to human health or the environment when
improperly managed. Solid waste, under the present guide-
lines, includes sludges, liquids, and gases in bottles that are
disposed of on the land.
From this working definition, a number of wastes have
been defined as hazardous. These include materials that are
ignitable, corrosive, reactive or explosive or toxic. These char-
acteristic identifiers are further delineated in the regulations.^4
In addition, using these general characteristics and specific
tests, the US Environmental Protection Agency has listed
materials from processes, such as electroplating, or specific
classes of materials, such as chlorinated solvents, or speci-
fic materials, such as lead acetate, or classes of compound, such
as selenium and its compounds, which must be managed as
“hazardous wastes” when they are disposed. This list changes
periodically. In many cases disposers have treated materials
not on the list as hazardous if they believe them to be so.
Some general classes of materials such as sewage,
mining and processing of ore wastes are excluded by law at
the present time.Managing WastesAdvancements in science and technology have given us
opportunities to address environmental contamination issuesin ways that are technologically more advanced, and more
cost and time efficient than ever before. Technologies that
were unknown, unproven and unacceptable to regulatory
agencies just a few years ago, now exist and are being imple-
mented at full scale. Regulations have changed, as have gov-
ernment policies governing cleanup and enforcement.
On a technical level, many ideas for hazardous waste
treatment and remediation were rejected a few years ago
by the engineering, business and regulatory community as
being unproven or unreliable. Entrepreneurial scientists and
engineers have adapted their knowledge of manufacturing
process chemistry and engineering to the sciences of geol-
ogy and hydrogeology and have refined the necessary equip-
ment and techniques for waste treatment and remediation.
Technologies have been tested at bench and pilot scale, and
many have proven effective on a large scale. Pressure by the
industrial community for engineers and regulators to reach a
common ground has driven the process.
Contaminated soil and groundwater remedial techniques
have tended toward the “active” end of the spectrum, with
the installation of pumps, wells and above ground treatment
systems of the capital and labor intensive variety. Progress
has been made at the opposite end of the spectrum, rang-
ing from intrinsic bioremediation, which involves no active
treatment, to incremental levels of treatment that are far less
costly than ex-situ pump and treat methods.
Programs like the EPA SITE (Superfund Innovative
Technology Evaluation) Program and other Federal test and
evaluation facilities, University research organizations and
privately sponsored technology incubator and test evaluation
facilities have been very successful in testing and establishing
new hazardous waste treatment and disposal technologies.
Currently, there are several dozen organizations nationally
that specifically focus on the development of emerging haz-
ardous waste treatment technologies. The results have been
very positive, and many of today’s front-edge technologies
are the offspring of programs such as these.
On a regulatory/compliance level, the extensive time
frame for receipt of approvals led many companies down
the path of the traditional treatment and disposal methods,
since they were “proven,” as well as being approvable by the
regulatory agencies. Environmental agencies have become
more sophisticated, and cleanup levels are more often based
on risk rather than standards set at an earlier data in tech-
nical and regulatory development. More than ever, agency
personnel are now trained as specialists in the various seg-
ments of the environmental industry, including risk assess-
ment, hydrogeology, remediation engineering and personal
protection. As a result, the agencies are often more willing
to engage in discussions regarding site specific conditions
and remedial goals. Further, modifications to state permit-
ting programs have allowed variations on typical operating
permits for new and emerging technologies that appear to
have promise.
An analysis of Superfund remediation activities indi-
cates that significant progress has been made in the use of
innovative technologies for site remediation. The predomi-
nant new technologies used at Superfund sites include soilC008_001_r03.indd 451C008_001_r03.indd 451 11/18/2005 10:28:44 AM11/18/2005 10:28:44 AM