April 2016 - ASTSWMO

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Achieving Remediation Success Using Good Science and Effective System Optimization Processes

April 2016 Chuck Whisman, PE – CH2M Lydia Ross – CH2M Chuck Blanchard, PE – CH2M

Agenda Discuss RPO in regards to:  Definition and Overview  Site Strategy and Conceptual Site Model (CSM)

 Visualization to Identify the Problem and Monitor Progress  Pilot Testing Pitfalls and Best Practices  System Design  Technology Specific Optimization

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Remedial Process Optimization Original Definition (USAF, 2001):  What is RPO and how has it evolved?  Why implement optimization on a programmatic basis?  More sites in O&M phase.

 High cost of operations.  Reserve accruals are significant.  Not meeting closure goals.

 Improve likelihood for success for new and existing remediation projects.  Helps drive competency, risk reduction, and operational integrity management.

 Integrates with sustainability drivers – more focus on social & economic impact assessment.

RPO is a deliberate and systematic approach to evaluate and improve site remediation processes while maximizing risk reduction for each dollar spent.

EPA - 2012 “Efforts at any phase of the removal or remedial response to identify and implement specific actions that improve the effectiveness and cost-efficiency of that phase. Such actions may also improve the remedy’s protectiveness and long-term implementation which may facilitate progress towards site completion.”

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Simplify the RPO Process

Complete Conceptual Site Model & Develop Site Strategy

Evaluate Applicable Remediation Technologies

Design, Install Operate the Most Appropriate System

Science to Guide the Assessment

Science to Guide the Assessment

Science to Guide the Design/O&M

• Know where mass is located and how much is present in soil/gw/NAPL.

• Perform in-field feasibility testing, when possible, to collect design data and information to compare potential technologies.

• Design better wells, piping, and equipment , while allowing for more “flexibility” for adjustments. (High Efficiency and Easy to Optimize!)

• Understand site variability in geology and how that may effect remediation.

• Perform life-cycle remediation costs of all applicable technologies.

• Incorporate optimization into O&M adjustments and data collection (Can the system perform optimization tasks automatically or allow for remote adjustments).

• Visualize the source area(s). • Consider all potential site uses and remediation endpoints (including social & economical impacts).

• Develop a system optimization plan with deign and operational goals that will help increase likelihood of reaching remediation endpoints.

CLOSURE

• Understand the value of high runtime and constant optimization adjustments.

You don’t want this process to be a cycle! 4

Remediation Optimization  Typical project involves assessment, pilot testing, establishment of design parameters, design, construction, and operation.  Remediation optimization generally involves optimizing mass recovery rates and ensuring that actual ROI >= design ROI. Does operation match or exceed design expectations?  At most sites, if design parameters are achieved, the site will remediate in a reasonable time.

 Issues occur when incorrect design parameters are selected or not achieved during operation

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Examples of Optimization Approaches  Independent Evaluation  “Fresh-eyes” review, brainstorming, shallow scope

 Unit Process Optimization  Focused effort on known trouble spots in process units

 Strategic Planning  Revisit the remedial strategy and/or regulatory objectives, regulator involvement may be required

 Smart O&M  Most efficient and cost-effective, on-going RPO with integrated team

 Comprehensive Remedy Evaluation  Encompasses the RPO spectrum, most significant potential cost savings

Solutions

Contracting

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RPO Focus Areas Site Characterization • • • • • •

Remediation Strategy • • • • •

Design Optimization

Accelerated site characterization (Triad) Conceptual site model (CSM) certainty Real-time measurements/monitoring Passive/no-purge samplers Multi-incremental sampling 3D visualization

Exit Strategy development Revisit cleanup levels Review risk assessment Life-cycle analysis Land use assumptions/controls

• • • • •

Alternative Technology

Remedial Process Optimization

Operation and Maintenance Review • Unit process optimization • Alternate or modified treatment • Automation/telemetry • Energy efficiency and materials reduction • Labor reduction

Objectives and endpoints definition Hazard and Operability (HAZOP) study Value Engineering Constructability review Green remediation

• • • • •

Aggressive source removal/reduction Innovative technologies Rely on natural processes Sustainable solutions Active to passive transition

Monitoring Optimization • • • • •

Reduced wells and frequency Reduced analytical Automation/telemetry Statistical tools for large sites Passive sampling methods 7

Sustainability Concepts & Optimization

 Remediation decisions that look at social and economic impacts may also be able to positively impact RPO efforts.  Waste reduction and/or re-use.  Energy efficiency (inc. solar, wind, and battery powered solutions).  Re-use of remediation equipment (flexible design requirements) and re-purposing sea boxes.  Mass reduction vs. mass displacement (are we just putting impacts in the ground into the atmosphere?).  Compare system recovery/remediation rates vs. NSZD – switch when appropriate.  Minimizing remediation duration & cost will minimize carbon footprint (less site visits and energy use).  Newer land-farming concepts (enhanced with heat, oxygen, oxidants, …), especially in remote areas. 8

Carbon Footprint Comparison – to put it in perspective

Carbon Source

Estimated Tons CO2/year

Hummer – 15,000 miles/yr

11

Prius – 15,000 miles/yr

4

15 Hp motor – 90% full load

55

250 cfm catalytic oxidizer– 40% duty

47

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Optimization – Should Also Look at System Efficiency & Cost Savings Ideas  1,500 gpm Chromium VI water treatment system Existing ion exchange resin was very expensive, so bench testing performed to look at other resins. >$1Mil saved annually.

 16MGD Pumping System – system upgrades resulted in more efficient electricity use and reduced air emissions. 10

Incorporating Asset Integrity Concepts into RPO

 Business Process Modeling  Threat/Risk Identification  Regulatory Requirements  Critical Operating Parameters

 Root Cause Analysis  Management of Change  Condition Assessment

 Failure Analysis  Process Safety Management  Competency 11

Optimization w/ Remedial Endpoints in Mind

 Understanding when the technology has reached “its end” (or the site has been remediated to the “maximum extent practical”).  When will natural source zone depletion (NSZD) make more sense?

 Are different site-specific risk-based endpoints acceptable based on changing conditions?  For NAPL sites, understand NAPL mobility analysis and risk assessment tools.  Review current life-cycle remediation cost options.  Should additional sampling be performed prior to system shutdown to verify source reduction.

 “MacGyver” it!

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Site Management Process Optimization (SMPO)

 Long-term planning tool for optimization of a portfolio of environmental sites  Optimization of existing remediation systems  Technical support logic for programming and planning  Systematic annual evaluation of site progress and management risk

 Collaborative- and consensus-based project to ensure results that meet wide range, and sometimes competing, site management objectives  Establishes a “tool” that can and should be revisited on a regular basis to update the business plan for the portfolio

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Multi-Site Optimization Example  Includes technical performance and site understanding uncertainty scores, input from risk inventory, and life-cycle costs  Low Certainty Score = Large Life Cycle Cost Delta = High Priority Technical Perform Certainty

Site CSM Certainty

Overall Site Certainty

Estimated Life Cycle Cost

Best Case

LF-20

83%

66%

73%

$420,000

$420,000

$620,000

No

SS-122

100%

98%

99%

$245,000

$245,000

$248,000

No

ST-123

64%

52%

59%

$2,776,000

$2,776,000

$6,296,500

Yes

SS-124

89%

94%

91%

$300,000

$300,000

$341,500

No

SS-125

68%

62%

65%

$1,800,000

$1,800,000

$2,710,000

Yes

SS-130

88%

78%

81%

$275,000

$275,000

$343,250

No

SS-139

98%

94%

95%

$245,000

$245,000

$265,000

No

SS-215

88%

95%

91%

$467,114

$467,114

$614,182

No

SS-216

91%

95%

93%

$424,257

$424,257

$519,767

No

HYDRANT

63%

47%

57%

$1,450,000

$1,450,000

$1,707,500

Yes

$8,678,371

$8,678,371 $14,058,699

Site Name

Total

Worst Case

Optimize Activity Priority 1

NOTES: Site is given priority if CSM Certainty < 70% OR deviation between Best Case and Worst Case is > 1.5. LCC = life-cycle cost to complete "Complete" is defined as a site-specific site management endpoint including long-term care LUCs or clean closure. Limit of 30 years.

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Development of a Site Strategic Plan – Incorporating RPO  Philosophy:  Look at the big picture and keep the endgame in mind  Re-evaluate as new key data are gathered or conditions change

Operating Facility

 Key Components  Site end use (and options for it); e.g. operating facility vs site currently owned by others  Potential risks (human and ecological) and liabilities  Corporate objectives, financial analysis used. Is site closure important or minimize annual spend  Regulatory program - requirements, opportunities, limitations, stakeholder engagement

Redeveloped Facility

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Remediation Strategy Development Component of CSM – Cross-Section

Conceptual Site Model (CSM)  Doesn’t need to be refined to begin with  Update as more information is obtained  Geology/hydrogeology/redox conditions  Contaminants, source, concentrations  Risk pathways

Remediation, management, and RPO strategies  Start thinking about them early

Data Gaps  Adjust the plan to collect information needed to minimize variables 16

Site Investigation Tools for Petroleum Hydrocarbons – Tools to Match the Site and the Objectives  Process of Selecting the tools

CSM Cartoon

 Evaluate existing CSM (e.g. geology/hydrogeology/LNAPL saturation)  Identify regulatory and other drivers  Preliminary consideration of remedial strategy  Identify data gaps  Select the tools to cost effective achieve; likely a combination of tools

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Site Visualization of CSM Information

 MIP and LIF tools can allow for low-cost assessment & visualization of source areas.  While it is preferred preremediation, it can also be performed during existing remediation:  for sites that have been in remediation for a long time, or  to compare to pre-remediation data).

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Visualizing Source Areas to Aid in the Remediation & Optimization Process

F Resolution of CSM – Identified Deeper NAPL

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TCE Discharge Location Identified – calculating concentration and mass COC flux Determine optimum locations for remediation wells, trenches, and/or focus.

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Other Examples of Visuals and Cost Data Determine the Degree of Hydraulic Control

Cost Evaluations

Drawdown (feet)

BTEX (μg/l) 20,000 16,000 12,000 8,000 4,000 2,000 1,000 500

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Typical 4-phase Distribution of NAPL

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NAPL Mobility Nomenclature

Residual Saturation Range No NAPL

NAPL can flow into wells

Migrating

NAPL present but cannot flow into wells

Mobile

Residual

Increasing NAPL Saturation

NAPL can flow to new area

Recoverable Sres

NAPL Saturated

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LNAPL Smear Zone Profile

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Laser-induced Fluorescence  Ultraviolet Optical Screening Tool (UVOST™)  Measures fluorescence of PAHs relative to a reference emitter (%RE)

 Accepted technology for delineation of LNAPL in subsurface soil  Direct-push  Real-time

 Site- and LNAPL-specific response  “Calibrate” against in-well petroleum samples or analytical results of soil samples

 Can be performed pre, during, and post remediation

Example LIF Data

 Advanced LIF: Ratio of wavelength response can be used to semi-quantitatively characterize variation in LNAPL quality  Type of fuel or fuel mixture  Degree of weathering

LIF Rig

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Site Investigation Tools for Petroleum Hydrocarbons – Variety of Tools and Approaches  Intact soil core –Pore fluid saturations  LNAPL Mobility Analysis: lines of evidence to evaluate if it can move  Pore fluid saturations and other parameters; calculations  Free product mobility lab testing: (Water Drive and centrifuge) NAPL Saturation in Sediment

Soil Core Preparation 26

Identify Product Saturation Zones Core Indexing and photography to target remediation depths

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Petroleum Source Identification Process

Suspected Petroleum Release Site History Products in Use

Known Releases

Age of Releases

Suspected Source

Basic Petroleum Identification (GC-FID) Gasoline

Diesel

Oil

Other

Advanced Petroleum Identification Biomarkers

PAHs

Simulated Distillation

VPH/EPH

ASTM D5739

PIANO

Stable Isotopes 28

What Does Basic Identification of a Petroleum Product Look Like? Crude Oil

Regular Gasoline

Diesel #2 Abundance vs. Time

30W Motor Oil JP-7

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Visual Comparisons  A visual comparison of chromatograms between the original product or a reference product can provide a good estimation of the weathering process.  This is an example of the alteration of gasoline due to evaporation only.

Chromatograms from Wigger and Torkelson

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Natural Source Zone Depletion (NSZD) – An Important Part of the CSM for LNAPL  NSZD is the term used to describe the natural processes of subsurface volatilization, dissolution, and biodegradation of petroleum in source zones  It is more significant than previously thought and results in measurable petroleum losses

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Information Management for RPO  Save Costs  Obtain Better Data and Information (higher quality and volume)  Reduce Risks & NOVs (allows for preventative management)  Allows us to make better business decisions (both technical & business informatics)  Expedite compliance and regulatory reviews and approvals (internal/external)  Assist compliance, regulatory, engineering, ER, HSSE, and permitting teams drives collaboration across client teams/companies/regulators  Automate work flow, alerts, and reports  Visualize and analyze trends and information  Drive efficiency in operations and compliance – can make everyone’s job easier  Make better optimization decisions! 33

Automate data collection, tracking, validating, and reporting!

 Remediation system data  Air and groundwater monitoring and compliances data  Life-cycle waste management/minimization  Compliance/site audits  Maintenance  Process data/remote sensors  HSSE data and monitoring  Asset data  Permit information

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General Workflow Overview: Maximizing Software Capabilities

Maps

Field Data

Charts

Lab Reports Electronic Forms

Remote Sensors

Database

Tables Models

Incoming information is automatically processed into report quality deliverables

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Information Management Solutions Can …  Work with existing systems  Integrate historical information  Bridge different groups (RP/consultant/regulator)  Save costs while reducing risks  Improve daily operations and management

 Provides important information at your fingertips to optimize remediation system performance or adjust to changes/challenges.

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Maintenance Management Confidential Client – Field Inspection Time Allocation

Paper Inspections

Tablet Inspections 1%

12%

13%

6%

Preinspection Office Work

6%

Field Inspection 25%

25%

Data Collection

19%

Data Entry Quality Control

68%

25%

50% office work 50% field work

7% office work 93% field work

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Field Data Collection

 Use any platform – computer, tablet, or smartphone  Make live updates  View layers of data and visuals  Manage and evaluate assessment and remediation data

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Reporting/KPI’s

Dashboards are a great way to integrate your strategic performance measures with the data collected from multiple sources into an easily used platform

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“Smart” SVE System for Automating System Optimization Actuating Valve

Vacuum Transducer

 Using Sensors/Meters & Automated Valves

SVE Wells

 Flow rates from individual SVE wells

1 2

 Applied vacuum on each SVE line

3

 In-line PID cycles across each influent SVE line for vapor concentration

Flow Transducer

 Data Processing  Flow rate & concentration used to calculate mass recovery rate from each SVE line  The PLC adjusts actuating valves to the overall maximize mass recovery rate

In-line PID (for concentration)

Process Controls (for adjustments) SVE Blower

 As certain SVE wells are remediated, the system reacts by constantly adjusting valves for optimized performance

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Remote System Control Screen Shots DPVE System

Biosparge System

AS/SVE Controls

AS/SVE System

Photos from Product Level Control,, 2016 41

Understanding a Site – Pre-Remediation

Hydrocarbon (HC) impacts at a former bulk storage terminal – focus on one large area of impact. Dissolved benzene reduction is the driver. • Mass of COC estimated in soil: 12,450 lb. • Mass of COC estimated as NAPL: 780 lb. • Mass of COC estimated in groundwater: 608 lb. Feasibility testing showed the following results from individual wells: • HC mass recovery rates up to 32 lb/day during SVE only • HC mass recovery rates up to 47 lb/day during AS/SVE

• HC mass recovery rates up to 59 lb/day during vacuum-enhanced SVE • NAPL recovery rates up to 12 gpd via total fluids recovery and 24 gpd using vacuum-enhanced recovery (mix of weathered gasoline & diesel) • Gas injection ROI of 15 feet at and average of 5 scfm for ozone design parameters

• SVE mass recovery data from 16 wells showed likely three different source areas.

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Learning From Remediation Failures & Successes?

 It is helpful to understand COC mass distribution and estimate mass volume prior to technology screening.  Use of in-field feasibility testing can help compare technologies, prove the best design approach, and understand site variabilities.  Optimization and up-time are both critical – and should be considered during system design (inc. well network, pipe sizes, controls, equipment). Up-time not important if the system isn’t effective.

 Do we know COC mass in soil, groundwater, and NAPL?  Are all source areas known?  It works in a bench test, but what about the field?

 What are the life-cycle costs of ALL my remediation options?  Are we collecting the correct field data during the assessment and feasibility testing?  How can I design the system to make optimization easier?

 It doesn’t have to be a new technology.

 Remediation is a contact sport. How not to choose a technology! 43

Important Pilot Testing Evaluation Parameters

Technology

Key Parameters to Understand in the Field

SVE

Flow, vacuum, influence, groundwater level, mass recovery rate

DPE

Flow (vapor/gw/NAPL), vacuum, influence, groundwater level, mass recovery rate

ISCO

Oxidant demand, volume delivered, inject-ability , bio enhancement, benefits of gas delivery, ..

LNAPL Recovery

Initial and target transmissivity, fingerprinting, NSZD, enhance recovery technologies, …

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Pilot Test Pitfalls – Third Party Review of Major O&G Client Remediation System Designs Site 1 - Long-term SVE pilot test was performed. Vapor recovery rate from well was not quantified. Site 2 - Red flags during AS/SVE pilot testing were ignored (highly variable vapor flowrates from wells, highly variable mass recovery rates from well, extremely low induced vacuums at observation wells).  System was installed anyway. Portions of vadose zone rapidly were remediated while other areas were largely unremediated. Site will require an extremely long remediation far in excess of estimated life-span.

Site 3 - Design of vapor abatement equipment based on pilot testing mass recovery rates and not on estimated mass of impact at site. This nearly always leads to oversizing the equipment and high utility costs toward the latter part of remediation.  Vapor abatement equipment only needs to be large enough to remediate site in a timely manner (say 2-3 years) as initial hydrocarbon recovery rates tend to drop rapidly.

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Pilot Test Best Practices - Clearly Define Goals and Outline Data Collection Needs  Pre-write data sheets so field personnel can easily double-check they have collected all requested data

- Staff pilot test with knowledgeable remediation engineer who can analyze data in field real time and make adjustments to test operation and data collection (with approval from client/regulator or within approved scope of work) to optimize pilot test  Extending a pilot test beyond planned operation to collect vital data based on site response is negligible cost compared to remobilizing for a second test, or having incomplete data for system design  Be mindful of measurement units on pilot test equipment - Test multiple technologies, locations, and/or depths to understand fluctuations due to variations in site cover and subsurface conditions. - Do not let rules of thumb be predictive of results  If results are inconsistent or unfavorable, do not continue with system design. 46

Know Your Equipment Pilot Test data is useless if the correct units of measurement are not recorded.

“SCFH” AIR

Check user manuals to be sure you don’t need to perform a conversion to achieve the listed unit Double-check settings to be sure you are measuring (CFH/CFM, Pressure/vacuum, etc.) Write down where the reading was collected to determine if it is pre/post dilution air, restrictions etc.

Dwyer Instruments, Inc. Installation and Operating Instructions

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Selection of Key Design Parameters

Use of incorrect design parameters will frequently lead to poor performance. Examples of some key design parameters for various technologies are listed below. Technology

Key Parameter

Supplemental parameter 1

Supplemental Parameter 2

SVE

Soil vapor velocity in key zones

Initial Mass recovery rate

Vacuum v. distance evaluation

DPE

Dewatering req. in target zones

Same as SVE parameters

Liquid recovery rate and optimum drawdown/efficiency

ISCO

Mass to be treated

Lifespan of selected oxidant

Travel distance of selected oxidant in target zones, contact time, DO enhancement

LNAPL Recovery/ Remediation

Initial and target transmissivity

LNAPL and/or groundwater ROI, enhancement (SVE)

Changes in volume, transmissivity, viscosity, …

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System Design Pitfalls - Third Party Review of Major O&G Client Remediation System Designs

Site A - Skimming system is being implemented at a site with a large amount of gasoline NAPL and a remedial goal of 5 ppb of benzene.  It was decided to sequence the remediation and start with product skimming prior to

multiphase extraction.  Site cannot close until residual NAPL is removed hence all effort removing mobile NAPL (only 30% of total) is wasted.

Site B - Mass of hydrocarbon at site estimated based on dissolved phase mass X an unscientific fudge factor (not based on soil analytical in saturated zone or even octanol-water portioning coefficients).  Mass of hydrocarbon was underestimated by easily a factor of 100 leading to selection of temporary injection of oxygenated water for the remedial technology.  Limited mass destruction resulted in zero reduction in GW concentrations 49

System Design Pitfalls - Third Party Review of Major O&G Client Remediation System Designs Site C - Length of remediation is frequently based on past experience and not the best available science.  This number is then used to perform life-cycle cost analyses which are used to pick the lowest cost remedial option.

 This can lead to selection of incorrect technology when the actual length of remediation exceeds the estimated length.

Site D - Lack of quantification of ROI or use of incorrect (but easy) metrics.  LNAPL skimmer ROIs based on rules of thumb, instead of recovery models, leading to extremely long (10-20 years) remediation duration..

 SVE ROIs based on vacuum vs. distance rather than soil vapor velocities (SVV).

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Examples of Designing for Optimization  Remediation Wells – using continuous-wrap well screen for high efficiency pumping (inc. NAPL recovery), SVE, AS, …  System Piping – reduced headless for higher range of adjustments – for moving liquids or gases. May also install piping for alternate technologies, if needed, or access/clean-out sumps.  System Equipment – design for flexibility – higher flow rates, more drawdown, larger ROI, …  Multi-Technology Approach – simultaneous or phased (if needed)  Sustainability Features – from re-use to power considerations.  Remote Monitoring – for automated or remote adjustments of just better data collection w/ sensors. 51

Evaluation of Actual Performance Data

 Design parameters are frequently based on short pilot tests or limited scope.  Once system is operational, substantially more data becomes available. So use it!  Performance data can be used to:  Reconfirm design parameters are applicable at entire site  Readjust system life span estimates (and expectations), if necessary  Make changes to the system (e.g. adding extraction wells or changing vacuum blowers)  Last resort – move to alternate remedial technology. Some technologies look like a good idea but simply don’t work in practice. 52

Understanding a Site – During Remediation Hydrocarbon (HC) impacts at a former bulk storage terminal – focus on one large area of impact. Dissolved benzene reduction is the driver. • Initial mass of COC estimated in soil: 12,450 lb. • Initial mass of COC estimated as NAPL: 780 lb.

• Initial mass of COC estimated in groundwater: 608 lb. (max dissolved benzene = 1,400 ppb) System performance - using SVE with total fluids recovery: • Year 1 mass recovery rates: Q1 (2,604 lb); Q2 (1,460 lb); Q3 (842 lb); Q4 (719 lb). Total = 5,625 (of 13,838 lb estimated, so ~ 41% reduction in Year 1 and approx. 8,213 lb left not including bio); • At end of Year 1: •

Max dissolved benzene = 280 ppb (80% reduction in max. concentration)



Remediation system continues to operate (with less wells and more aggressively per well);



MIP study and soil sampling will be conducted to evaluate remaining source areas;



Risk assessment will be re-evaluated with updated information.



Adding air sparging (piping/vaults added at time of installation) or using short-term oxidation injection being considered. 53

Optimizing Requires Analyzing System Data & “Reacting” to Improve Results

SVE Well

Flow Rate (scfm)

Mass Recovery Rate (HC (inches of water) lb/day)

Applied Vacuum

SVE-1

45 scfm

10 iw

21 lb/day

SVE-2

20 scfm

47 iw

32.0 lb/day

*SVE-3

79 scfm

2 iw