| System Parameters
portion of table now follows: |
| Air Flow Rate |
The air
flow rate is a parameter set for a vapor extraction or
treatment system. The measurement of air flow rate is
standardized (i.e., measured with flow meters). |
No |
Air flow
rate affects the rate of volatilization of contaminants
in technologies that rely on transferring contaminants
from a soil or aqueous matrix to air, such as soil
bioventing, soil vapor extraction, and ground water
sparging. For technologies involving oxidation processes,
this parameter affects the availability of oxygen and the
rate at which oxidation occurs (e.g., for biotreatment or
incineration processes). |
| Mixing Rate/ Frequency |
Mixing
rate or frequency is the rate of tilling for land
treatment, the rate of turning for composting, and the
rotational frequency of a mixer for slurry phase
bioremediation. |
No |
The mixing
rate affects the rate of biological activity (through
increased contact between oxygen and contaminants) and
volatilization of contaminants. |
| Moisture Content |
Procedures
for measuring soil moisture content are relatively
standardized. Soil moisture content is typically measured
using a gravimetric ASTM standard: D 2216-90, Test Method
for Laboratory Determination of Water (Moisture) Content
of Soil and Rock. Moisture content as a treatment system
operating parameter characterizes the amount of water and
aqueous reagent added to the soil (for example, moisture
content for slurry phase bioremediation refers to the
solid to liquid ratio). |
No |
The
moisture content affects the rate of biological activity
in soil bioventing, land treatment, composting, and
slurry phase bioremediation technologies. Contaminants
must be in an aqueous phase for biodegradation to occur,
and water is typically added to a soil to maintain a
sufficient level of moisture to support biodegradation. |
| Operating Pressure/Vacuum |
Operating
pressure or vacuum is measured using a pressure or vacuum
gauge, such as a manometer. The measurement of this
parameter is relatively standardized. |
No |
Operating
pressure/vacuum affects the rate of volatilization of
contaminants in technologies that rely on transferring
contaminants from a soil or aqueous matrix to air, such
as soil bioventing, soil vapor extraction, and ground
water sparging. |
| pH |
Procedures
for measuring and reporting pH are standardized (e.g.,
Method 9045 in EPA SW-846). The pH of soil and ground
water is adjusted during ex situ treatment as an
operating parameter by the addition of acidic and
alkaline reagents. |
No |
pH affects
the operation of technologies that involve chemical or
biological processes, such as soil flushing, soil
washing, and bioremediation processes. For example, in
soil washing, contaminants are extracted from a matrix at
specified pH ranges based on the solubility of the
contaminant at that pH. |
| Pumping Rate |
Pumping
rate is the volume of ground water extracted from the
subsurface. The pumping rate is measured through a
production well or treatment system using a flow meter or
a bucket and stopwatch. |
No |
Pumping
rate affects the amount of time required to remediate a
contaminated area, and is important for technologies that
involve extraction of ground water, such as soil
flushing, and pump and treat. |
| Residence Time |
Residence
time is the amount of time that a unit of material is
processed in a treatment system. Residence time is
measured by monitoring the length of time that a unit of
soil is contained in the treatment system. |
No |
Residence
time is important for ex situ technologies, such as land
treatment, composting, slurry-phase soil bioremediation,
incineration, and thermal desorption, to measure the
amount of time during which treatment occurs. |
| System Throughput |
System
throughput is the amount of material that is processed in
a treatment system per unit of time. |
No |
System
throughput affects the costs for capital equipment
required for a remediation and operating labor for ex
situ technologies such as slurry phase soil
bioremediation, soil washing, incineration, and thermal
desorption. |
| Temperature |
Temperature
is measured using a thermometer or thermocouple. |
No |
For
bioremediation technologies, temperature affects rate of
biological activity. For stabilization, incineration, and
thermal desorption, temperature affects the physical
properties and rate of chemical reactions of soil and
contaminants. |
| Washing/Flushing Solution
Components/ Additives and Dosage |
The
components and dosages of washing and flushing solutions
are site- and waste-specific "recipes" of
polymers, flocculants, and coagulants. The type and
concentrations of additives for a particular treatment
application are determined based on site and waste
characterization, treatability and performance tests, and
operator experience. The actual amounts added are
measured based on the volume and concentration of
additive solutions metered into the treatment system. |
No |
For soil
flushing and washing technologies, the types and dosages
of additives affects the solubility and rate of
extraction for contaminants; and thus affects the costs
for constructing and operating flushing and washing
equipment. |
| Biological
Activity portion of table now follows: |
| Biomass Concentration |
Biomass
concentration is the number of microorganisms per unit
volume in a treated or untreated aqueous matrix. Biomass
concentrations are typically measured by direct plate
counts. Portable water test kits are available for field
tests. Methods 10200 through 10400 from Standard Methods
for the Examination of Water and Wastewater are used in
laboratory analyses of biomass concentration. |
Yes |
Biomass
concentration is an important parameter for slurry phase
soil bioremediation and in situ ground water
biodegradation. Biomass is necessary to effect treatment
and thus the concentration of biomass is directly related
to performance. |
| Microbial Activity Oxygen
Uptake Rate (OUR) Carbon Dioxide Evolution Hydrocarbon
Degradation |
Oxygen
uptake, carbon dioxide evolution, and hydrocarbon
degradation are all used to measure the rate of
biodegradation in a treatment system. Oxygen uptake is
measured using ASTM D 4478-85, Standard Test Methods for
Oxygen Uptake. Carbon dioxide evolution is measured with
a carbon dioxide monitor. Hydrocarbon degradation is
measured by sampling the influent to and effluent from
the treatment system and analyzing samples for organic
constituents, such as total petroleum hydrocarbons (EPA
SW-846 Method 9073). |
Yes |
Microbial
activity is an important parameter for soil bioventing,
land treatment, composting, and slurry phase soil
bioremediation technologies. Hydrocarbon degradation is
commonly used as an indicator of treatment performance
for these technologies, while OUR and carbon dioxide
evolution are used in specific applications to supplement
the hydrocarbon degradation data. |
| Nutrients and Other Soil
Amendments |
Nutrients
usually consist of nitrogen and phosphorus (and trace
inorganic constituents such as calcium and magnesium),
and are typically reported as a ratio of carbon to
nitrogen to phosphorus. Carbon is measured as total
organic carbon, with EPA SW-846 Method 9060. Nitrogen is
measured as both ammonia nitrogen using ASTM D 1426-89,
Test Methods for Ammonia Nitrogen in Water, and as
nitrite-nitrate using ASTM D 3867-90, Test Method for
Nitrite-Nitrate in Water. Phosphorus is measured using
ASTM D 515-88, Test Methods for Phosphorus in Water.
Calcium and magnesium are measured using ASTM D 511-88,
Test Method for Calcium and Magnesium in Water. Other
soil amendments may include bulking agents for composting
(e.g., sawdust). |
Yes |
Nutrients
and other soil amendments can affect soil bioventing and
in situ ground water biodegradation as this parameter
directly affects the rate of biological activity and,
therefore, contaminant biodegradation. This is also
applicable to ex situ soil remediation technologies such
as land treatment, composting, and slurry phase soil
bioremediation. |
| Soil Loading Rate |
Soil
loading rate is the amount of soil applied to a unit area
of a composting system. |
No |
The soil
loading rate affects the rate of biological activity and
can impact the costs for operation |