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SITE REMEDIATION. Pedro A. García Encina Department of Chemical Engineering University of Valladolid. CONTAMINATED SITES. In the past much wastes were dumped indiscriminately or disposed of in inadequate facilities. These problems went ignored as did spills of product or leaks from tanks.

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site remediation

SITE REMEDIATION

Pedro A. García Encina

Department of Chemical Engineering

University of Valladolid

contaminated sites

CONTAMINATED SITES

In the past much wastes were dumped indiscriminately or disposed of in inadequate facilities. These problems went ignored as did spills of product or leaks from tanks.

Theses practices contaminated sites with hazardous substances that pose a threat to human populations.

slide3
HAZARDOUS WASTE - Characteristics

Corrosivity - waste that is highly acidic or alkaline, with pH <2 or pH >12.5.

Ignitability - waste that is easily ignited.

Reactivity - waste that is capable of sudden, harmful reaction or explosion.

Toxicity - waste capable of releasing specified, toxic substances to water in significant concentrations.

slide4
HAZARDOUS WASTE - Major Categories

Inorganic Aqueous Waste - liquid waste composed of acids, alkalis or heavy metals in water.

Organic Aqueous Waste - mixtures of hazardous organic substances (pesticides, petrochemicals) and water.

Oils - liquid waste composed primarily of petroleum derived oils (lubrication oils, cutting fluids).

Inorganic Sludges/Solids - sludges, dusts, solids, non-liquid wastes containing hazardous inorganic substances (metal fabricating wastes).

Organic Sludges/Solids - tars, sludges, solids and other non-liquid wastes containing organic hazardous substances (contaminated soils).

slide5
Toxicity Characteristics of Hazardous Wastes

Acute Toxicity - results in harmful effects shortly after a single exposure, such as cyanide poisoning.

Chronic Toxicity - may take up to many years to result in toxic effects, such as cancer or long-term illness.

hazardous waste treatment
HAZARDOUS WASTE TREATMENT
  • Source Reduction
  • Recycling
  • Treatment
  • Disposal
waste minimization preventing tomorrow s remediation problems

WASTE MINIMIZATION-PREVENTING TOMORROW´S REMEDIATION PROBLEMS

Many of today´s contaminated sites are the result of accepted lawful waste-disposal practices of years ago

site remediation1
SITE REMEDIATION
  • Source Reduction (?)
  • Recycling (difficult)
  • Treatment
  • Disposal
site remediation2

SITE REMEDIATION

METHODOLOGY

· SITE CHARACTERIZATION

· REMEDIAL ALTERNATIVES ANALYSIS

· DESIGN, CONSTRUCT AND OPERATE

slide11
SITE CHARACTERIZATION - Definition

Site Characterization is defined as the qualitative and quantitative description of the conditions on and beneath the site which are pertinent to hazardous waste management.

slide12
SITE CHARACTERIZATION - Goals

The goals of site characterization are to:

1. Determine the extent and magnitude of contamination

2. Identify contaminant transport pathways and receptors

3. Determine risk of exposure

slide14
Identification of Receptors and Pathways

receptors

storage

tank

residual

gasoline

gasoline vapors

Domestic

well

groundwater

table

floating gasoline

groundwater flow

slide16
METHODS OF SITE CHARACTERIZATION
  • Remote Methods
  • Seismic Survey
  • Soil Resistivity
  • Ground Penetrating Radar
  • Magnetometer Survey
  • Direct Methods
  • Auger Drilling
  • Rotary Drilling
  • Soil Excavation
slide17
REMOTE SUBSURFACE CHARACTERIZATION

Seismic Survey

Shock wave propagates faster through rock than soil, depth to rock and rock type can be determined.

Geologic Wave

Material Velocity (m/s)

Dry sand 500-900

Wet sand 600-1800

Clay 900-2800

Water 1400-1700

Sandstone 1800-4000

Limestone 2100-6100

Granite 4600-5800

Source

Geophones

Seismic

wave

Soil

Rock

slide18
Resistivity

Soil Type Range (ohm-m)

Clays 1-150

Alluvium and sand 100-1,500

Fractured bedrock Low 1,000s

Massive bedrock High 1,000s

REMOTE SUBSURFACE CHARACTERIZATION

Soil Resistivity

Soil/rock type can be determined by soil resistivity.

R=soil resistivity(ohm-m)

s=electrode spacing (m)

V=measured voltage (volts)

I=applied current (amperes)

Current Meter

Battery

Voltage Meter

s

Current flow lines

slide19
DIRECT SUBSURFACE CHARACTERIZATION

Auger Drilling

  • Useful in unconsolidated geologic materials.
  • Sample collection easy, intact samples can be collected with hollow-stem auger.
  • Cannot be used where significant consolidated rock is present.
  • Does not alter subsurface geo-chemistry.

Rod inside hollow stem for removing plug

Flight

Removable

Plug

Drill Bit

slide20
DIRECT SUBSURFACE CHARACTERIZATION

Rotary Drilling

  • Useful in consolidated geologic materials, can drill through rock.
  • Subsurface samples contaminated with drilling mud.
  • Air-rotary may blow volatile contaminants into surrounding subsurface structures (basements).
  • Mud-rotary alters subsurface chemistry.

mud pump

mud pit

slide21
DIRECT SUBSURFACE CHARACTERIZATION

Drilling through confining layers may allow the spread

of contamination from one hydrologic unit to another.

monitoring well

leaking

tank

soil

contaminated ground water

confining layer (clay)

uncontaminated water

slide22
DIRECT SUBSURFACE CHARACTERIZATION

Soil Excavation

Advantages

Disadvantages

  • No specialized equipment, typically uses backhoe.
  • Subsurface samples can be collected directly.
  • Inexpensive.
  • Good source removal mechanism.
  • Useful only in unconsolidated geologic materials to a maximum depth of 10 meters.
  • Large surface disturbance.
  • Excavation not useful for long term groundwater monitoring.
slide23
SOIL CHARACTERIZATION

Soil Contaminant Sampling

  • Performed during drilling or excavation.
  • Collection of samples from several depths within the soil profile.
  • Where volatile compounds are present, sampling should be done in air-tight glass containers. No headspace should be left in the containers.
  • Samples should be chilled for transportation to the laboratory.
slide24
GROUNDWATER CHARACTERIZATION

Extent of Contamination:

Successive wells should be drilled until the extent of the groundwater contaminant plume is defined.

slide25
AIRBORNE CONTAMINATION

Source: Waste pile

Release Mechanism: Volatilization

Transport Medium: Air

Exposure Mechanism: Inhalation or skin contact

Exposure Point: May be distant from source, depends on concentration and wind speed

slide26
AIRBORNE CONTAMINATION

Measurement Techniques

Laboratory Analysis: Samples can be collected in the field in an air-tight bag (Tedlar™ ) and sampled in the laboratory.

Field Analysis: Samples can be analyzed in the field via handheld instrumentation such as a photo-ionization detector for volatile organic compounds or a draw-tube collection device (such as a Drager™ tube).

slide27
AIRBORNE CONTAMINATION

Reducing Airborne Hazards

  • Airborne Hazards Reduction can be accomplished through:
  • Source removal
  • Covering the source (prevents volatilization)
  • Dilution with clean air (if indoors)
slide28
ASSESSING EXPOSURE RISK

Definition: Assessment of exposure risk seeks to determine the probability that contamination will migrate to a receptor (human or animal) and be ingested (eaten, inhaled, or absorbed by the skin).

slide30
EXPOSURE PATHWAYS

2

Contaminated groundwater: exposure from drinking or from breathing contaminated vapors liberated during bathing

3

4

1

slide31
EXPOSURE PATHWAYS

2

3

4

Inhalation of airborne contaminants: volatilized from the source and carried by wind.

1

slide32
EXPOSURE PATHWAYS

2

3

4

Direct contact with contaminated soil: exposure from skin contact with contaminants in soil.

1

slide33
EXPOSURE PATHWAYS

2

3

4

Indirect contact: exposure to contaminant from crops or animals which have accumulated contamination from soil or groundwater

1

site remediation3

SITE REMEDIATION

METHODOLOGY

· SITE CHARACTERIZATION

· REMEDIAL ALTERNATIVES ANALYSIS

· DESIGN, CONSTRUCT AND OPERATE

development of alternatives
DEVELOPMENT OF ALTERNATIVES
  • Identify general response to actions for each objective
  • Characterise media to be remediated
  • Identify potential technologies
  • Screen the potential technologies
  • Assemble the screened technologies into alternatives
alternative selection

ALTERNATIVE SELECTION

1. Long term effectiveness

2. Long term reliability

3. Implementability

4. Short term effectiveness

5. Cost

alternative selection1

ALTERNATIVE SELECTION

  • Qualitative assessment of how well an alternative meets the remedial action objective over the long term
  • To calculate by means of a complete analysis the residual risk (Risk represented by untreated contaminants or residuals remaining at the site)

1. Long term effectiveness

2. Long term reliability

3. Implementability

4. Short term effectiveness

5. Cost

alternative selection2

ALTERNATIVE SELECTION

1. Long term effectiveness

2. Long term reliability

3. Implementability

4. Short term effectiveness

5. Cost

  • Is only a issue with the alternatives that leave untreated contaminants or treatment residuals at site at the conclusion of the implementation period
  • One tradeoff that require careful consideration at most sites is whether to treat or to contain
alternative selection3

ALTERNATIVE SELECTION

1. Long term effectiveness

2. Long term reliability

3. Implementability Function of

4. Short term effectiveness

5. Cost

  • History of the demonstrated performance of a technology
  • Ability to construct and operate it given the existing conditions at the particular site
  • Ability to obtain the necessary permits from regulatory agencies
alternative selection4

ALTERNATIVE SELECTION

  • Deals primarily with the effects on human health an the environment of the remediation itself during its implementation phase
    • Health and environmental risk
    • Worker safety
    • Implementation time

1. Long term effectiveness

2. Long term reliability

3. Implementability

4. Short term effectiveness

5. Cost

alternative selection5

ALTERNATIVE SELECTION

  • The weight given to the cost when evaluating alternatives depend upon the particular guidance of the agency
    • Capital costs (the cost to construct the remedy)
    • Operating and maintenance cost (O & M) (post-construction expenditures)

1. Long term effectiveness

2. Long term reliability

3. Implementability

4. Short term effectiveness

5. Cost

treatment alternatives

TREATMENT ALTERNATIVES

On site

· In situ

· Ex situ (Excavation)

Off site (Excavation & Transportation)

slide43
HAZARDOUS WASTE TREATMENT METHODS

Physical/Chemical Methods: Mass transfer and chemical transformation processes resulting in the removal or remediation of contamination by abiotic, not combustion means.

Biological Methods: Transformation or binding of contaminants by microorganisms, principally bacteria.

Waste Stabilization: Containment of wastes such that they pose no further threat to receptors.

Combustion Methods: Transformation of organic wastes by burning.

slide44
SOIL VAPOR EXTRACTION

Description - soil vapor extraction (SVE) uses a vacuum applied to soil to remove volatile organic compounds (VOCs) from the unsaturated zone.

Uses - effective for contaminants with high vapor pressure, such as gasoline compounds, chlorinated solvents.

Advantages - low cost, simple design and operation, efficient removal of VOCs from unsaturated zone.

Disadvantages - not effective for non-volatile compounds, not effective in low permeability soils or where groundwater is close to the surface, may need to treat off-gas in another process, does not address groundwater contamination.

slide45
SOIL VAPOR EXTRACTION

Vapor Extraction Pump

contaminated soil

air movement through

contaminatedsoil

Water

Table

Contaminated Groundwater

slide46
AIR STRIPPING

Description - enhances volatilization of dissolved contaminants from water. Can be used for treatment of either process wastewater or groundwater pumped to the surface.

Uses - remove volatile organic compounds (VOCs) from water.

Advantages - simple operation, efficient removal of low concentrations of VOCs.

Disadvantages - high capital cost, design intensive, may need to treat off-gas in another process.

slide47
Packed Column Air Stripper

Water Inlet (contaminated)

Air

Outlet (contaminated)

Types of Packing Materials

Pall ring

Raschig ring

Berl saddle

Intalox saddle

Tri-pack

Packing Material

Water Outlet (clean)

Air Inlet (clean)

slide48
Packed Column Air Stripper

Typical Air-Stripping Column Specifications:

Diameter: 0.5 - 3 meters

Height: 1 - 15 meters

Air/Water ratio: 5-200

Pressure drop: 200 - 400 N/m2

Stripping Column

Off-gas Treatment System

slide49
CARBON ADSORPTION

Description - carbon adsorption uses granular activated carbon (GAC) to remove organic contaminants from a water or vapor stream. Contaminated air/water is pumped through the GAC unit and contaminants adsorb onto carbon particles by electrostatic forces.

Uses - effective for a wide range of organic contaminants. Is commonly used both for process waste treatment and for hazardous waste remediation.

Advantages - easy to install, can completely remove many organics, can treat either water or vapor stream.

Disadvantages - high operating expense, carbon must be changed periodically, contaminants are not mineralized.

soil washing or flushing

SOIL WASHING OR FLUSHING

Description - Excavated soil is flushed with water or other solvent to leach out contamination. Based on the principles of solid-liquid extraction

Uses - remove organic wastes and certain (soluble) inorganic wastes

Advantages - simple operation, efficient removal of organic contaminants (VOC, semi VOC and halogenated organics) . For metal, it has been successful at extracting organically bound metals (tetraethyl lead)

Disadvantages - Longer washing times and soil-handling problems with lower-permeability clays and clay-like soils

slide52
CHEMICAL OXIDATION

Description - organic chemicals in extracted groundwater or industrial process wastewater are transformed into less harmful compounds through oxidation by ozone (O3), hydrogen peroxide (H2O2), chlorine (Cl2) or ultraviolet radiation (UV). UV is often used in combination with ozone or hydrogen peroxide.

Uses - effective for a wide range of organic contaminants such as VOCs, mercaptians, and phenols. Can also be used for some inorganics, such as cyanide. Process is non-specific, oxidant will react with any reducing agent present in the waste, such as naturally occurring organic matter.

Advantages - effective, reliable treatment for waste streams which contain a variety of contaminants, often used for drinking water purification.

Disadvantages - high operating expense, incomplete oxidation may create chlorinated organic molecules (if Cl2 is used), generation of oxidizing agent typically cannot vary with fluctuating contaminant concentrations.

slide53
Power System

Control System

Effluent

H2O2 Storage

Reaction Chamber

flowmeter

Influent

UV Lamps

CHEMICAL OXIDATION Reactor Configuration

slide54
Fraction TCE Remaining

CHEMICAL OXIDATION - Results

Initial TCE =58 mg/L

slide55
CHEMICAL OXIDATION - Results

Halogenated aliphatic destruction by H2O2 and UV at 20oC.

slide56
CHEMICAL OXIDATION - Design Considerations

Thermodynamics: Free energy available from reactions

Oxidant Free Energy (E, volts)

O3 2.07

H2O2 1.78

Cl2 1.36

Kinetics: Reaction must proceed to necessary completion within the residence time in the reactor vessel. Combination of UV with ozone or hydrogen peroxide increases reaction kinetics .

Design Steps:

1) Will oxidation reaction proceed with contaminants present?

2) What is the contact time necessary between the oxidant and the contaminants present?

slide57
SUPERCRITICAL FLUID EXTRACTION

Description - contaminated liquid or solid is placed in a reactor vessel with the extraction fluid, which is heated and pressurised to the critical point (see chart). In treatment of hazardous wastes, fluids most commonly used are water and CO2, some organic solvents may also be used.

Uses - supercritical fluid extraction can be used to treat contaminated soils, sediments, sludges, solids or liquids.

Advantages - effective treatment for process wastes or extracted soil or groundwater which is either highly contaminated with organic compounds or with very recalcitrant (hard to treat) organics

Disadvantages - expensive, solids must be reduced in size to 100 um to pass through high pressure pumps.

slide58
SUPERCRITICAL FLUID EXTRACTION Reactor Configuration

Schematic diagram of reactor for the extraction of organic compounds from water, CO2 is the extraction fluid.

slide59
SUPERCRITICAL FLUID EXTRACTION Solvent Selection Criteria

Cost - water, CO2 are least expensive

Recoverability - solvent must be recoverable for process to be economical

Hazard in use - SFE involves high temperatures and pressures which reactor vessels must be built to withstand

Critical temperature and pressure - the higher the critical T and P of the solvent, the greater the operating expense

Distribution coefficient - determines the solvent/ contaminant ratio which can be used.

slide60
MEMBRANE PROCESSES

Electrodialysis - separation of ionic species from water by direct-current electric field. Useful for removal of charged ions and metals from water.

Reverse Osmosis - solvent is forced through a semi-permeable membrane by the application of pressures in excess of the osmotic pressure. Useful for removal of metals and some organics.

Ultrafiltration - separates dissolved contaminants on the basis of molecular size. Lower limit for molecular weight is approximately 500.

slide61
BIOLOGICAL PROCESSES

Description - biodegradation uses micro-organisms (bacteria) to remove organic contaminants from vapors, liquids or solids. Most organic contaminants are utilized by bacteria as both a carbon and energy source.

Uses - biological processes are effective on both process waste streams and remediation of soil and groundwater. Biodegradation systems for soil and groundwater can by designed either in-situ (in place) or ex-situ (removed from the ground).

Advantages - low cost, low site disturbance, effective for many organic contaminants.

Disadvantages - long clean-up times, not effective for inorganic contaminants, specialized conditions necessary for chlorinated solvent degradation.

slide62
BIOLOGICAL PROCESSES
  • Necessary Constituents:
  • microorganisms capable of degrading contaminants
  • contaminants in aqueous (water) phase
  • available electron acceptor present

Aerobic Degradation: takes place in the presence of molecular oxygen (O2), the most energetically favorable electron acceptor.

Anaerobic Degradation: when O2 is not available, other compounds can act as electron acceptors for biodegradation processes, such as NO3, Fe+3, Mn+4, SO4, and CO2.

slide63
o

D

G

(kJ/

mol mineralized)

-3913

-3778

+3

Fe

-2175

-358

-37

Energy Available from Electron Acceptor Processes

Electron

Toluene

Benzene

Acceptor

O

-3566

2

-

NO

-3245

3

+4

, Mn

~

-2343

~

SO-2

-340

4

CO

-136

2

slide64
BIOLOGICAL PROCESSES - Remediation of soil and groundwater

In-situ biodegradation:

Natural attenuation

Engineered systems

Ex-situ biodegradation:

Pump and treat systems for groundwater

Landfarming systems for soil treatment

slide65
-

-2

In-Situ Biodegradation - Natural Attenuation

slide66
Typical Contaminant / Electron Acceptor

Concentrations with Distance

-2

-

-2

-

Natural Attenuation of Contaminants

slide67
Relative Importance of Electron Acceptor Processes at 25 Air Force Sites

Aerobic

Methanogenesis

Respiration

39%

10%

Denitrification

14%

Iron (III)

Reduction

8%

Sulfate

Reduction

29%

Source: Wiedemeier et al., 1995

slide68
)

)

(

)

(

(

1 mmol Fe+2

1 mmol BTEX

92 mg BTEX

(20 mg/l Fe+2 produced )

56 mg Fe+2

36 mmol Fe+2

1 mmol BTEX

Stoichiometric Conversion Example: Iron Reduction

BTEX + 36Fe+3 + 21H2O 36Fe+2 + 7CO2 + 7H2O

Assume 20 mg/l Fe+2 observed in aquifer

Calculate BTEX consumed per unit volume:

= 0.9 mg/l BTEX consumed in aquifer

Calculate groundwater flux and total BTEX consumed:

Flux = vwh = 1000 ft3/d = 7500 gal/d = 28x103l/d

Assume: Vgw = 1 ft/day Plume width = 100’ Plume height = 10’

BTEX consumed = (28x103l/d) (0.9 mg/l) = 25 g BTEX/day

slide69
In-Situ Biodegradation - Engineered Systems

Air-sparging/nutrient addition system

Groundwater

treatment unit

air

compressor

water/nutrient

supply tank

injection

well

water table

contaminated

soil

air

sparger

pump

confining layer

slide70
In-Situ Biodegradation - Engineered Systems

Infiltration gallery, recirculating system

slide71
water table

In-Situ Biodegradation - Engineered Systems

Combination air injection/extraction system

slide73
Vacuum Pump

Liquid phase

Bioreactor

Oil/water

Separator

Vacuum

Air removal

Water Table

Liquid

Hydrocarbon

Contaminant

Skimmer

Pump

Ex-Situ Biodegradation - Pump and treat

slide74
Ex-Situ Biodegradation - Biofiltration

Moisture

Addition

Biofilter

Blower

Vapor

Extraction

Well

Biofilter is colonized with bacteria capable of degrading contaminants. Media can be soil, peat, compost, or manufactured packing material.

Contaminated Soil

slide75
Ex-Situ Biodegradation - Biopiles

Gas Monitoring Probes

Air Intakes

Irrigation

Piping

Wood Chips

Weights

Tarp

Aeration

Pipes

Crushed

Stone

Soil

Curb

Contaminated Soil

Impermeable

Base

Leachate

Pipe

Aeration Pipe

slide76
Ex-Situ Biodegradation - Landfarming
  • Procedures:
  • Excavated soils are spread onto the ground surface to a depth of less than 0.5 meters.
  • Underlying soils should be low permeability, or a clay liner or impermeable membrane should be used to prevent contaminant migration to groundwater.
  • Landfarmed soils should be tilled every 2-3 months and kept moist.
slide77
WASTE STABILIZATION AND CONTAINMENT
  • Procedure: Excavated soils or process wastes are secured such that contaminant migration will not occur (containment), or are mixed with binding agents that solidify the waste and prevent leaching or release of the contaminants (stabilization).
  • Processes:
  • Encapsulation
  • Sorption processes
  • Polymer stabilization
  • In-situ vitrification
slide80
COMBUSTION METHODS

Description: waste combustion can take place in hazardous waste incinerators, cement kilns, or industrial boilers. Most significant design parameter is the heat value of the waste. Many concentrated organic wastes will support combustion without supplemental fuel.

Applicable wastes: all organic wastes can be mineralized using combustion methods. Metals are oxidized in the combustion process and are either vented in gaseous form or are concentrated in ash. Metals prone to gaseous emission are arsenic, antimony, cadmium, and mercury.

Procedure: Wastes are graded for suitability for combustion. Waste analysis also indicates the proper fuel/air mixture for complete combustion.

containment

CONTAINMENT

Frecuently it is necessary to minimize the rate of off site contaminant migration employing containments technologies to minimize risk to public health and environment.

Containment technologies may be associated with other technologies to implement a long-term clean-up strategy for the site

containment1

CONTAINMENT

Active system components require considerable effort and on-going energy in put to operate (For example pumping wells)

Pasive system components work without much attention, except maintenance (such a cover)

slide87
SELECTION OF REMEDIAL ALTERNATIVES

1. Data Needs

A. Site Characterization

B. Regulatory Disposition

C. Risk Assessment

2. Establishment of Site Objectives

A. Clean-up Level Necessary

B. Long-term Liability

C. Costs

3. Development and Analysis of Alternatives

A. Development of Possible Alternatives

B. Analysis of Alternatives for Effectiveness

4. Remedial Option Selection, Implementation, and Monitoring

A. Remedial Option Selection

B. Implementation

C. Long term Site Monitoring

slide88
SELECTION OF REMEDIAL ALTERNATIVES
  • Data Needs:
  • Understand extent and magnitude of contamination. A thorough site characterization is necessary. Chemical fate and transport must be understood.
  • Determine risk to potential receptors. This is necessary to correctly focus efforts where they are most needed. Typical exposure pathways include groundwater wells and airborne contaminants.
  • Determine what limits or requirements are placed on the clean up by government regulations. It is important to insure that all participants understand and agree on the goal of the remedial effort.
slide89
SELECTION OF REMEDIAL ALTERNATIVES
  • Establishment of Site Objectives:
  • Establishment or negotiation of acceptable clean-up goals is necessary prior to selection of a remedial process.
  • The extent of long-term liability for the site should be considered.
  • Costs of each remedial option must be considered along with the financial means of the financially responsible party. Options for cost assistance should be considered at this stage (national and international).
slide90
SELECTION OF REMEDIAL ALTERNATIVES
  • Development and Analysis of Alternatives:
  • A list of potential remedial alternatives is compiled for further study based on their feasibility to clean up the site.
  • Criteria for selection of a remedial alternative are effectiveness, reliability, cost, time to implementation, and time to clean up.
  • Before a remedial solution is chosen, a detailed plan of implementation should be formulated to insure that the technique is capable of remediating the site to the goals prescribed.
slide91
SELECTION OF REMEDIAL ALTERNATIVES
  • Remedial Option Implementation and Monitoring:
  • After a remedial option is selected, construction contracts and engineering designs must be completed. Can be done by employee engineers or contractor engineers (must be familiar with technology chosen).
  • Long term site monitoring should continue to insure that the solution is working, and that further contaminant migration does not occur. Monitoring should include all applicable media (groundwater, soil vapor, and air).
ley 10 98 de residuos

LEY 10/98 DE RESIDUOS

CONTAMINATED SITES

· Depends of Comunidades Autónomas

· List of contaminated places (priority to clean-up)

· Need to clean-up the site

· The responsible of the contamination

· The owner of the site

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