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Advances
in Methods to Stage Injection and Determine Subsurface
Coverage of Regenesis HCR and ORC and Other Materials
Alan Livadas, Vironex, Inc., Wilmington, DE
Enhanced
In-Situ Chemical Oxidation Using the PRP System
Ronald
J. Scrudota, SUNY at Oswego, Oswego, NY
Jeffrey R. Chiarenzelli, SUNY
at Potsdam, Potsdam, NY
LNAPL
In-Situ Remediation in Difficult Setting
Rich Werner, Environmental Consulting, Inc., Norristown,
PA
Mark Vigneri, EBSI, Wayne, NJ
Dr. Bill Mchaffey,Pelorus Labs
Dr. Bill Slack, FRx
In-Situ
Chemical Oxidation of CVOCs in Fill and Saprolite
Janet Strike, P.E., Malcolm Pirnie, Inc., Wilmington, DE
Matthew P. Lesley, P.G., Malcolm
Pirnie, Inc., Wilmington, DE
Daniel P. Sheehan, P.E., Malcolm
Pirnie, Inc., Wilmington, DE
Minimizing
Injection Points for Dry Cleaner Remediation
Jeff
W. Brudereck, Whitman
Companies, Inc., East Brunswick, NJ
Richard Britton, Whitman
Companies, Inc., East Brunswick, NJ
Todd Gerber, Whitman
Companies, Inc., East Brunswick, NJ
Chris Blake,
Whitman Companies, Inc., East Brunswick, NJ
Hydraulic
Fracturing and Injection for In-Situ Co-Precipitation of
Metals
John
S. Haselow, PhD, P.E., Redox Tech, LLC, Aiken, SC
Bernd
W. Rehm, P.G., C.P.G., RMT, Inc., Madison, WI
Jim F. Crowley, P.E., RMT, Inc., Madison, WI
Advances
in Methods to Stage Injection of ORC, HRC and Other
Materials
Alan
Livadas,
Vironex, Inc., 5801 Kennett Pike, Suite A, Wilmington, DE
19807 Phone:
302-661-1400, Fax: 302-661-1460, Email: alivadas@vironex.com,
Website: www.vironex.com
The
discussion will provide a general overview of advances in
the actual delivery of ORC, HRC and other remediation
compounds in an attempt to provide practical options for
real projects and field applications.
How
You Inject is Equally Important as what You Inject
The injection of ORC, HRC and other remediation compounds
has rapidly become a widely accepted practice for
addressing contaminated sites. With the advances in the
industry’s understanding of the in situ remediation
process we are seeing an important question asked
regarding the success of a project: “How are you
injecting the compound at your site?” In developing your
plan, it is crucial not to overlook the obvious: proper
execution will contribute to the effectiveness of the
outcome. In short: how you inject is equally
important as what you inject.
Safety
First
First and foremost, safety is the responsibility of
everyone involved with the project. This applies to the
field crews as well as the engineers and remediation
design team. Many remediation compounds are relatively
benign; however, there are also those that are potentially
very harmful if handled improperly. Accidents are the
result of making safety an after-thought to the in situ
remediation process. Safety first.
Common
Injection Method
A very common method for injecting remediation compounds
is to use a single portable pump in tandem with the direct
push rig. The DPT operator starts by hammering a single
rod chain with an expendable point to the desired depth.
The injection hose from the pump is secured to the top of
the rod chain. As the rods are slowly retracted, the
expendable point falls off into the hole and the compound
is injected through the exposed down-hole tip at the
bottom of the rod chain. This method has been used for
years, however it does not address some of the subtle
issues faced in the field relative to the accurate
delivery of the compound and creating cost and time
efficiencies in the overall execution of the work scope.
Advanced
Injection Methods
As with any technology, experience has taught us ways of
improving the in situ injection process. Today
“dedicated injection rigs” are used in tandem with
single or multiple direct push rigs. Specific pumping
pressures, specific flow rates and specific temperatures
apply to different materials in different media. Injection
systems are designed as self-sufficient units that can
adapt to site conditions as needed. These units contain
single or multiple pumps, an independent water supply, an
independent power source, pre-heating tanks, and compound
mixing tanks. They are capable of moderating the
temperature of the compound, moderating the pressure of
the pump(s), and moderating the flow rate of the
injections to maximize efficiency in the field.
Improvements in the tooling allow us to isolate targeted
zones and avoid creating or exaggerating preferential
pathways. This tooling also addresses the substantial
backpressures created in certain applications. These
advances maximize time efficiency between borings,
minimize product loss, and present a more professional
overall field operation to your client.
“Reinjectable”
wells have become the preferred practice on sites where
injections are anticipated over an extended period of
time. Again this process is designed to create cost
efficiencies for the overall remediation project.
Operations
and Case Studies
Performance criteria will vary from project to project
based on a number of variables, however, general
performance parameters for actual delivery of HRC, ORC and
other compounds will be covered as a point of reference.
Specific Case Studies will be presented to provide
perspective on these parameters.
Ronald
J. Scrudato, ERC,
319 Piez Hall, SUNY at Oswego, Oswego, NY 13126, Tel: 315
312 2883, Email:
scrudato@oswego.edu
Jeffrey R. Chiarenzelli, Department
of Geology, 233 Timerman Hall, SUNY at Potsdam, Potsdam,
NY 13676, Tel: 315 267 3401, Email: chiarejr@potsdam.edu
The
Programmable Release Process (PRP) involves the use of
inserts in existing or newly drilled wells to release
reagents to contaminated soils and groundwater to affect a
three phased remedial process including: 1. direct
oxidation of the contaminants of concern (COCs), 2.
modification of the groundwater redox chemistry; and 3.
maintenance of the modified geochemistry of the impacted
groundwater. In
anaerobic plumes, a dilute peroxide solution is gravity
released to the impacted groundwater to affect in situ
Fenton Reagent reactions to oxidize chlorinated and
non-chlorinated VOCs and SVOCs.
As the peroxide solution disseminates into the
plume, oxygen is released thereby modifying the redox of
the plume to enable aerobic biodegradation to take effect.
The aerobic state of the plume is maintained by the
controlled and continued release of the peroxide solution.
In
this paper, two PRP field applications are described
including a BTEX/MTBE spill site in Saratoga Springs NY
and a former gas manufacturing site in Utica NY impacted
by PAHs, BTEX, cyanide and select trace metals. The
Saratoga Springs site had been under continued remediation
since 1988 using conventional pump and treat technologies.
Within four months of the PRP application, oxygen
levels reached saturation and the source area BTEX
groundwater concentrations were reduced from about 15 mg/L
to 20 ug/L.
The
range of PRP applications includes applications for the
smear and vadose zones of contaminated sites.
The dilute peroxide solution can be used in
existing wells to create and maintain an artificial
hydraulic head. The
increased head floods the normally unsaturated regions of
the site within the immediate vicinity of the well
providing a mechanism to degrade smear and unsaturated
zone contaminants of concern.
By maintaining an elevated head of reagents within
the contaminated soils, it is possible to degrade
contaminants within the normally unsaturated regions of an
impacted site. This
PRP application was used to degrade PAH and BTEX-contaminated
fill material at the former gas manufacturing facility
located in Utica NY. The PRP application also elevated the
groundwater dissolved oxygen concentrations within the
plume thereby promoting aerobic degradation of the COCs.
LNAPL
In-Situ Remediation in Difficult Settings
Richard Werner,
P.G., ECI, 500 East Washington Avenue, Suite 375,
Norristown, PA
Mark Vigneri,
EBSI, 1127 Crossing Way, Wayne, NJ 07470, Tel:
973-633-5011
Dr. Bill Mahaffey,
Pelorus Labs
Dr. Bill Slack,
FRx
Free
Product Fuel is especially challenging to remediate as it
is both an immediate risk to health and safety, and
prevents the remediation of dissolved phase contaminants
for closure. Environmental
Consulting, Inc. (ECI) has extensively used Environmental
Business Solutions International, Inc.’s (EBSI)
On-Contact Remediation Process® family of in-situ
technologies to configure methods to field detect
free-product, recovery for disposal when possible and then
chemically treat the remaining free-product layer.
Our
case studies include live gas stations, under buildings,
near live tanks and other difficult settings.
The free product treatments start with specialized
field testing to delineate the free product’s extent and
condition along with factoring in additional vectors of
cubic volume that are probably impacted but not easily
verifiable. Once
remediation starts, Propagation Injection Points are
installed in a manner as to allow for the recovery of free
product at the surface though biased displacement.
As the Propagation is installed, being an inerted
conductive plane at our sites, the beginning stages of the
hydraulic fracturing like technology allows for a quick
recovery of free product near the injection point.
Once the Propagation is installed it becomes a trap
zone for free product and allows both vacuum truck service
and in-situ chemical treatment.
One
Propagation based injection point can reach up to a 60
foot radius and can do the work of 9 to 36 wells. The chemical processes used are specialized for free product
and are real-time controlled for efficiency and the
suppression of temperature and LEL levels.
The
entire set of project steps move along like one continuous
mobilization for the customer and has been extremely
effective at area sites.
We offer this service under pay-for-performance
contracting available from EBSI.
In-Situ
Chemical Oxidation of CVOCs in Fill and Saprolite
Janet
M. Strike, P.E.,
Malcolm Pirnie, Inc., 824 N. Market St. Suite 710,
Wilmington, DE 1980, Tel:
302-884-6902, Fax: 302-658-2068
Matthew P. Lesley, P.G.,
Malcolm Pirnie, Inc., 824 N. Market St. Suite 710,
Wilmington, DE 19801, Tel:
302-884-6901, Fax: 302-658-2068
Daniel P. Sheehan, P.E.,
Malcolm Pirnie, Inc., 824 N. Market St. Suite 710,
Wilmington, DE 1980,1Tel: 302-884-6919, Fax:
302-658-2068
Soil
and groundwater remediation via chemical oxidation has
been performed at a former industrial site with high
levels of chlorinated volatile organic compounds (CVOCs),
including trichloroethene (TCE) and its degradation products, as well as a number
of non-chlorinated volatile organic compounds.
Specific challenges to remediation of this site
included: 1) soil and groundwater containing high levels
of TCE and other volatile organic compounds and
2) the presence of low permeability soils beneath the
Site. Through
literature research, the results of a bench scale
treatability study, and site operating restrictions,
direct oxidation of the impacted media using chemical
oxidants with a catalyst was chosen as the remedial
strategy. In order to achieve the required distribution of
the chemical oxidant in the low permeability soils, and
enhance the contact between the contaminants and the
oxidant, a hydrofracturing technology was selected.
Due to its ability to substantially increase the
effective treatment volume in the subsurface, this
technology was expected to perform better and more cost
effectively than other remedial technologies employed in
the treatment of similar constituents in similar geology.
Remediation is on-going at the site, and the first
round of sampling following the hydrofracturing and
initial injections of hydrogen peroxide indicated an
overall reduction in TCE concentrations in the on-site
groundwater of approximately 30%. However, soil sampling
results indicated that between hydrofractured horizons,
CVOC concentrations remain at or near the original
concentration, and that the level of increased
permeability due to the initial hydrofracturing is not
sufficient to access all targeted areas of the subsurface.
Additional hydrofractures were installed and a more
persistent oxidant (i.e., potassium permanganate) injected
into the subsurface. It is anticipated that the additional
hydrofracturing combined with the injection of two
oxidants into the subsurface will significantly improve
the effectiveness of the remediation at the site.
Minimizing
Injection Points and Maximizing Delivery of Oxidants for
Dry Cleaner Remediation
Jeff
W. Brudereck, Richard Britton, Todd Gerber, and Chris
Blake, The Whitman Companies, Inc., 116 Tices Lane, Unit
B-1, East Brunswick, NJ, Tel: 732-390-5858
The
Whitman Companies, Inc. (Whitman), a New Jersey-based
environmental consulting and engineering company, teamed
with Environmental Business Solutions International, Inc.
(EBSI) to perform in-situ remediation of chlorinated
ethenes using chemical oxidation at an active dry cleaning
facility located in a strip mall in Tinton Falls, Monmouth
County, New Jersey. Soils
at the site are described as silty sands with some clay
content near grade, and glauconitic, dark green to black
silty sands with increasing clay content at depth.
The highest concentrations of Tetrachloroethene (PCE)
detected in soils and ground water were 1,400 mg/kg and
120 mg/kg, respectively.
These concentrations were detected in shallow soil
and ground water below the building slab in the location
of the former dry cleaning machine.
Prior to injection of oxidants, hydraulic
fracturing was performed at the site to install subsurface
propagations, which form high permeability zones in low
permeability material, to maximize efficient delivery of
oxidants throughout the impacted area.
One (1) deep and two (2) shallow propagations were
installed in the interior of the unit to treat soil and
ground water below the dry cleaners.
Following completion of the fracturing, chemical
oxidant injections using EBSI’s On-Contract Processâ
were initiated to treat contaminated soils and
groundwater.
As
compared to the other methods of applying in-situ chemical
treatment, this remedial process required fewer injection
points to treat the area of concern, and allowed for
greater distribution of oxidants throughout the low
permeability soils at the site.
Only three (3) injection points to cover the
interior of the building and the source area whereas other
approaches at similar sites have required 10 to 15
injection points to address the same area and interval.
Fewer injection points translates to lower costs to
the site owner, less on-site chemical addition time, and
less disruption to the dry cleaning operation and
surrounding leaseholds.
Hydraulic
Fracturing and Injection for In-Situ Co-Precipitation of
Metals
John
S. Haselow, PhD, P.E., Redox Tech, LLC, 1075 Brookhaven
Drive, Aiken, SC 29803,
Tel:
803-502-0020, Fax: 803-641-1621
Bernd W. Rehm, P.G., C.P.G. and Jim F. Crowley, P.E., RMT,
Inc., 744 Heartland Trail, Madison, WI 53717-1934, Tel:
608-831-4444, Fax: 608-831-3334
Effective treatment of metals in soil and groundwater often requires
manipulation of the oxidation-reduction potential (ORP)
and stabilization of the pH. The goal of almost all metals
treatment is to provide long-term, stable and insoluble
species. Depending upon the metallic compound, either
reducing or oxidizing conditions may be required to create
an insoluble species. There are many soluble reducing or
oxidizing agents that can be fairly easily injected. Often
metals contamination is associated with low pH (acidic)
conditions that have dissolved and mobilized metals of
concern. Most metal
complexes are least soluble at neutral pH
conditions. An essential component of an acceptable metals
treatment strategy is the ability to provide long-term
buffering of the pH. RMT’s proprietary metals treatment
chemical, EnvironBlend,
provides long-term stabilization of pH.
EnviroBlend can provide enormous acid
neutralization capacity (ANC) to provide long-term pH
control. For a recent site, EnviroBlend was estimated to
provide at least 1,000 years of acid neutralization based
on a modified USEPA multiple extraction procedure.
EnviroBlend is a insoluble solid at ambient conditions. Hydraulic fracturing and
slurry injection has been utilized to provide delivery of
the material in low permeability environments. EnviroBlend.
As
was recently injected for arsenic treatment
under very acidic conditions at a site in South Carolina.
With hydraulic fracturing, a 50 weight percent slurry
solution was injected into low permeability material at
rates up to 25 gallons per minute. Impact was visually
observed greater than 20 feet from the injection point.
The pH increased to near equilibrium conditions, and
arsenic concentrations dropped to regulatory acceptable
levels.
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