Decision Support Tools i

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Decision Support Tools – i

Decision Support Tools

SLIDE DST-1 – Decision Support Tools

SLIDE DST-2 – Condense Decisions through Iterative Data Collection and Assessment SLIDE DST-3 – Same Tools...Different Toolbox

SLIDE DST-4 – What is a Decision Support Tool (DST)? SLIDE DST-5 – Examples of Decision Support Tools SLIDE DST-6 – On-line DST Matrix

SLIDE DST-7 – Advantages

SLIDE DST-8 – What are the Key Functions of Decision Support Tools? SLIDE DST-9 – Examples of DSTs in the Matrix

SLIDE DST-10 – Schematic of DST Use

SLIDE DST-11 – Example Screening Level DST: BIOSCREEN SLIDE DST-12 – BIOSCREEN Output: Plume Centerline

SLIDE DST-13 – FIELDS (Field Environmental Decision Support) SLIDE DST-14 – FIELDS Interface

SLIDE DST-15 – Spatial Analyst and Decision Assistance (SADA) SLIDE DST-16 – SADA User Interface

SLIDE DST-17 – Mini Case Study: Using DSTs to Guide and Communicate Project Decisions: Marino Bros. Scrapyard Site

SLIDE DST-18 – FIELDS: Visualize/Communicate Nature and Extent and Calculate Bulk Removal Volume

SLIDE DST-19 – SADA: Delineate Excavation Extent on a Rectangular Grid and Export Results

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DST-1

EPA

Decision Support Tools

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DST-2 Decision Support Tools

DST-2

EPA

Condense Decisions Through

Iterative Data Collection and

Assessment

Keep It Simple,

Stupid

“One should not increase, beyond what is necessary, the number of entities required to explain anything”

Occam

Notes:

• Beginning early on and continuing throughout the life of a project, it may be necessary to (re)evaluate the benefit of action versus the benefit of collecting additional data

(Occam’s Razor). Information such as site history, contaminants potentially used and released, anticipated breakdown products of those chemicals, identification and

refinement of potential exposure pathways, toxicity of compounds of potential concern (COPCs), and future land use are examined to identify the need for the collection of more data.

• With the help of experts and technical resources/guidance, regulators and project

technical leads usually find a method to quantitate the magnitude or nature of a problem. Unfortunately, the environmental problems faced during site restoration projects are more complex than we can easily make conform to a simple set of algorithms, and classical statistical tools are generally inadequate at best. Data concerning nature and extent of contamination, sampling and analytical errors, and decision errors are usually assessed to the degree possible. Decisions broaden in scope but too often significant sources of uncertainty remain unexplored or their shear magnitude forces professionals to ignore them, or to rationalize why an adequate management response is not possible.

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DST-3

EPA

Same Tools…Different Toolbox

Tools » Query tools » Spatial interpolation » Secondary sampling » Delineation Toolboxes (DSTs) » SADA » FIELDS » VSP Notes:

• Until recently, organized methods for the management of uncertainty were difficult to implement during the early stages of a project planning. However, with the advent of a new generation of decision support tools (DST), the technology is now widely available to manage uncertainty and condense the decisions using the data management and analysis tools provided in these new “toolboxes.” DSTs can help the project team

organize data, test assumptions, develop sampling strategies, and winnow the universe of potential solutions to the environmental problem.

• DSTs such as SADA and FIELDS are comprehensive software programs that contain data management and querying tools that allow the user to either define a data dictionary or accommodate input from an external database or data source. They also include a variety of spatial interpolation tools, some which are easy to implement and some which require some prior familiarization with them (spatial interpolation will be discussed further in this section). Secondary sampling schemes allow new sample locations to be identified on the fly. DSTs also include tools that allow the user to delineate portions of a grid above regulatory thresholds and calculate the mass and volume of the contaminant and the cost of remediation or removal.

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DST-4

EPA

What is a Decision Support Tool

(DST)?

DSTs are interactive software tools used by

decision-makers to help answer questions, solve

problems, and support or refute conclusions.

They can be incorporated into a structured

decision-making process for environment site

clean-up.

Notes:

• Decision Support Tools (DSTs) provide a concise representation of the essential decision making issues for a particular environmental decision. Environmental decisions that can be addressed with DSTs include site characterization, monitoring, supporting no further action (NFA) decisions, or selecting between alternative remedial decisions.

• DST software output allows comparisons to made between alternate remedial strategies based on decision variables such as cost and risk. However, DSTs are a particularly important component of the Triad approach because they allow data to be organized, visualized and analyzed in the field while the investigation is unfolding, thus condensing the decision-making process.

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DST-5

EPA

Examples of Decision Suport Tools

DSTs vary in level of complexity, cost and ease of use: » Screening- Generally available in public domain,

relatively easy to use, easy for stakeholders to understand. Examples: BIOSCREEN, BIOCHLOR. » Comprehensive- Can provide cradle-to-grave

analysis for smaller sites or sites that are not too complex. May be public domain or proprietary. Examples: SADA, FIELDS.

» Advanced- Sophisticated level of analysis and graphics. Most are proprietary. Require substantial investment in time and expertise. Examples: GMS, ArcGIS.

Notes:

• DSTs may be public domain or proprietary, and range in the level of sophistication and detail from “screening” level to very advanced.

S Screening - Generally available in public domain, relatively easy to use, easy for

stakeholders to understand. Examples: BIOSCREEN, BIOCHLOR.

S Comprehensive - Can provide cradle-to-grave analysis for smaller sites or sites

that are not too complex. May be public domain or proprietary. Examples: SADA, FIELDS.

S Advanced - Sophisticated level of analysis and graphics. Most are proprietary.

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DST-6

EPA

On-line DST Matrix

Intended to help users screen public domain DSTs based on project-specific needs

Consists of matrix (table), additional comments and “bubble” diagram that presents DSTs by functional area (e.g. Sample Plan Development) Many of the DSTs included in

this matrix relate to use of the Triad approach

Will be available on-line later this spring

Notes:

• The EPA has conducted a brief evaluation of a representative group of 20 public domain DSTs and summarized the information gleaned from the evaluation in a “matrix.” EPA will make the matrix available on-line to users who wish to screen DSTs based on project-specific needs.

• The DST evaluation was not a verification exercise or a comparative analysis of one DST against another. Rather, the goal of this exercise was to ascertain if a person with

general technical experience could perform a basic task using the DST within a relatively short time frame.

• The “front page” graphic for the on-line matrix is shown on this slide. The graphic depicts 12 functional areas into which the 20 DSTs were grouped (some DSTs are

included in more than one functional area). Clicking on a blue oval will take the user to a page that presents the tools in the corresponding functional area. Clicking on the green circle in the center of the graphic will take the user to the entire matrix of 20 DSTs.

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DST-7

EPA

Advantages

Base maps can be imported easily

Sampling coordinates output and input easily

Initial and secondary optimized sampling schemes

Most include multiple tools for data assessment

Real-time export of results

Compatible with most web applications

Flexible

Free

Notes:

• DSTs may be used as a “gateway” to a project's database. Many DSTs (such as FIELDS) provide tools to facilitate data capture and management. For instance, FIELDS provides a tool to create a user-defined data dictionary. Both FIELDS and SADA have a column matching utility that allows the user to quickly upload comma-delimited ASCII data files (which can be created by saving an Excel spreadsheet with a *.csv extension).

• A new generation of DSTs will be able to accommodate continuous data streams from field instruments. For instance, an EPA-developed DST called Rapid Assessment Tool (RAT) has just been released. RAT is designed receive continuous data streams from real time instruments and merge the sampling data with location data from global positioning system (GPS) equipment. The data can be received and merged using wireless technology if the laptop is outfitted with a RS-232 port.

• The user should also understand that the DST will not provide presentation-quality graphics in many situations and must familiarize himself with the limitations of each program (many of these are described in subsequent slides). Finally, a DST in and of itself is not a silver bullet that will automatically reduce costs and streamline the effort on its own. The DST should be part of an overall Triad strategy that utilizes real-time measurement tools, relational databases and improved methods (electronic, if possible) for transferring data.

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DST-8

EPA

What are the Key Functions of the

Decision Support Tools?

Sampling Plan Development

Visualization, Geospatial Interpolation and Geostatistics Modeling

Remedial Process Selection Data Acquisition

Data Management

Long-Term Monitoring Optimization Statistical Analysis

Emergency Response/Compliance Risk Assessment

Site Screening

Cost Estimation and Cost-Benefit Analysis

Notes:

• Each DST performs unique tasks, commonly referred to as functions. The DSTs in the matrix were categorized into 12 functional areas, as identified by website descriptions, software menus, and user manuals.

• The twelve functional areas depicted on the “Front page” of the web site divide the DST matrix into smaller sub-matrices (on separate web pages) that allow the user to hone in on the type of tools of interest. Individual DST’s often perform many functions,

therefore a single DST may be included under more than one functional area on the web page.

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DST-9

EPA

Examples of DSTs in the Matrix

Notes:

• This slide provides some examples of DSTs that are included in some of the functional areas. A table of all 20 DSTs included in the on-line DST matrix is provided in the insert pages that follow this slide. The matrix may be expanded with additional DSTs in the future.

S ARAMS is a software platform that incorporates various existing databases and

models for source descriptions, media fate and transport, exposure pathways, intake and uptake, and effects (health impacts) into a conceptual site model (CSM) framework.

S BIOSCREEN is a natural attenuation screening model that simulates remediation

through natural attenuation (RNA) of dissolved hydrocarbon species at petroleum fuel release sites.

S FIELDS Tools for ArcView are a collection of 11 independent ArcView

extensions (modules) that provide spatial analysis in support of environmental decision-making.

S MAROS is a database application developed to assist users with groundwater

data trend analysis and long term monitoring optimization at contaminated groundwater sites.

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S SourceDK is a decision support tool for developing a screening-level model to

estimate groundwater remediation timeframes and associated uncertainties at sites where groundwater is contaminated by a source in the unsaturated zone.

S Visual Sample Plan (VSP) provides statistical solutions to sampling design

problems. VSP helps the user select the correct number and location of samples so that a required confidence level for decision-making can be achieved.

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DST-10 EPA

Schematic of DST Use

Select initial sample locations in DST and export Use contours to identify new locations

Survey locations and collect samples Import results to DST and plot contour maps Evaluate results against decision criteria Analyze samples using field-based methods Site characterized? Done Start No Yes Notes:

• DSTs can be used to guide a field program in conjunction with a dynamic work plan. This slide provides a schematic diagram of how a DST such as SADA or FIELDS can be integrated into the dynamic work strategy. DST-supported field decisions should be indicated in appropriate sections of the dynamic work plan, for instance on a decision flow diagram.

• The table on the following insert page shows how a DST-supported dynamic work strategy can increase the efficiency of an investigation, as compared to a traditional approach that uses a static work plan.

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Table 1: Level of Effort Comparison Between a Traditional and a Triad Streamlined Data Management Approach

Traditional Approach Streamlined Approach

Data Collection: Location 20 minutes per location 1 minute per location Data Collection: Analytical 10 minutes per sample 10 minutes per sample Data Recording and QC 2 minutes per sample 1 minute per sample Upload Location and

Analytical Data to Graphics Device

30 minutes 2 minutes

Plot Location Data 5 minutes 5 minutes

Post Analytical Data 5 minutes 5 minutes

Contour Data 120 minutes 30 minutes

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Decision Support Tools

DST-13

Decision Support Tools

Tabl e 2: Sum m ar y of DST Sof tw ar e De ve lo pe r/ Spons or De sc ri pt io n W eb Li nk Uni ve rs ity o f Te nne ss ee Int eg ra te d m odul es f or e nv ir onm en ta l ch aracterization an d d ecision -m akin g, in clu di ng visu alization , geosp atial an aly sis, statistical an aly sis, h um an h ealth risk assessmen

t, ecological risk assessmen

t, cost/b en efit an aly sis, samp lin g d esign , an d decision an aly sis. http ://www. tiem. ut k. ed u/ ~s P N N L V S P p rovid es statistical solu tion s to sam plin g d esign , m ath em atical an d statistical algorith ms, an d a u ser-frien dl y visu al in terface, wh ile an swerin g two imp ortan t que st io ns in s am pl e pl anni ng : Ho w m any samp les are n eed ed ? W here sh ou ld th e samp les b e taken ? http ://d qo .p nl .gov/vsp / A rm y Co rp s ERDC ARAMS i nc or po ra te s v ar io us e xi st in g da ta ba se s a nd m ode ls f or s our ce de scrip tion s, m ed ia fate/tran sp ort, ex po su re pa th way s, in take/u pt ake, an d effects (h ealth im pacts) in to a con cep tu al site m od el (C S M ) fr am ew or k. The hub o f ARAMS i s a n ob je ct -o ri en te d CSM ba se d o n t he F ram ework for R isk A naly sis in Mu ltim ed ia E nviron m en tal S ystem s (F R A ME S ). http ://www. wes. army .m il/el/arams/aram s. ht ml Ar go nne Co de f or e va lua tio n o f r is k po se d by rad ioactively con tamin ated sites. N R C h as appr ov ed t he us e o f RESRAD f or do se evalu ation b y licen sees in volved in decommission in g, N R C staff evalu ation of w as te di sp os al r eque st s a nd do se e va lua tio n of sites b ein g reviewed b y N R C staff. F ollows E P A risk assessmen t gu id an ce for supe rf und. http ://web .ead .a nl .gov/resrad

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Decision Support Tools Sof tw ar e De ve lo pe r/ Spons or De sc ri pt io n W eb Li nk DST-14

Decision Support Tools

FI EL DS EPA Re gi on 5 T he FI EL DS To ol s f or Ar cV ie w © (version 3. 5) are a collection of A rcV iew-ba sed ex te ns io ns ( m odul es ) t ha t i nc lude Sa m pl e D esign

(as well as a lin

k to V isu al S am ple Pl an , VSP) , Da ta ba se Que ry , Ge os pa tia l m ode lin g a nd Ana ly si s, a nd Hum an He al th an d E cological R isk A ssessmen t. http ://www. ep a. gov/region 5f ield oftware. ht m NAS USGS/ N FESC Na tu ra l At te nua tio n So ft w ar e ( NAS) w as de sign ed as a a grap hi cal u ser in terface for calcu latin g estimates for th e p eriod of time req ui red to ach ieve site-sp

ecific goals at sites

con tamin ated with eith er fu els or ch lorin ated solven ts. T he u ser may ch oose to evalu ate th e effects of sou rce red uc tion or comp lete removal in terms of meetin g a u ser-sp ecified con tamin an t con cen tration at a sp ecific p oin t of comp lian ce. http ://www. cee. vt. ed u/ na s/ So ur ce D K A FCEE So ur ce DK i s a c om put er de ci si on s uppo rt sy stem for estim atin g rem ed iation tim efram es an d assessin g th e u ncertain ty associated with th ose estimates. P rogrammed in th e M icrosoft E xcel sp read sh eet en viron m en t, S ou rceD K u ses th ree relatively simp le ap pr oach es to estim ate rem ed iation tim efram es an d th e un certain ty in th e tim efram e estim ate. A ll th ree ap pr oach es in clu de meth od s to estim ate th e u ncertain ty in an y rem ed iation tim efram e estim ate http ://www. gsi-ne t.com /S oftware/S ou rceD K .h tm

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Decision Support Tools

OR AFCEE B IO CHL O R i s a s cr ee ni ng m ode l t ha t sim ulates rem ed iation b y n atu ral atten ua tion of d issolved solven ts at ch lorin ated solven t release sites. B IO C H L O R can b e u sed to simu late solu te tran sp ort with ou t d ecay an d solu te tran sp ort with b iod egrad ation m ode le d a s a s eque nt ia l f ir st -o rde r pr oc es s with in on e or two d ifferen t reaction zon es. http ://www. ep a. gov/ad a/csmos/mod ioch lor. ht m l P L U M E III A F C E E B IO P L U M E III i s a 2 D , f in ite d if fe re nc e m od el for sim ulatin g th e n atu ral atten ua tion of o rg ani c c ont am in an ts in g ro und-w at er due to th e p rocesses of ad vection , d isp ersion , so rp tio n, a nd bi od eg ra da tio n. The m ode l ha s be en in te gr at ed w ith a s ophi st ic at ed g ro und-water m od elin g p latform kn own as E IS . A grap hi cal u ser p latform allows th e u ser to create, en ter an d ed it d

ata for mod

el sim ulation . http ://www. ep a. gov/ad a/csmos/mod io pl um e3 .ht m l AL OHA Na t'l Sa fe ty Co unc il CAMEO ® is a sy stem of software appl ic at io ns us ed w ide ly to pl an f or a nd resp on d to ch emical emergen cies. T he C A M E O sy stem in tegrates a ch emical da ta ba se a nd a m et ho d t o m ana ge th e da ta , an a ir di sp er si on m ode l, a nd a m appi ng cap ab ility . A ll m od ul es work in teractively to sh are an d d isp lay critical in form ation in a tim ely fash ion . http ://www. ep a. gov/ad a/csmos/mod ioch lor. ht m l

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Decision Support Tools

BI OSCREEN AFCEE B IO SCREEN i s a s cr ee ni ng m ode l w hi ch sim ulates rem ed iation th rou gh n atu ral at te nua tio n o f di ss ol ve d hy dr oc ar bo ns a t pe troleu m fu el release sites. T he software, pr ogrammed in th e M icrosoft E xcel sp read sh eet en viron m en t in clu de s th ree di ff er ent m ode l t ype s. The m ode l i s de si gn ed to s im ul at e bi od eg ra da tio n by bo th aerob ic an d an aerob ic reaction s. http ://www. ep a. gov/ad a/csmos/mod els/b ioscrn .h tm l MN A T oolb ox S an di a (D O E ) M N A toolb ox id en tifies p rim ary atten ua tion pa th way s, an d p oin ts ou t p rocesses th at m igh t m itigate again st MN A for p articu lar con tamin an ts. E ach con tamin an t mod ul e lead s to a scorecard th at u ses site-sp ecific input pa ra m et er s t o g aug e t he pr ob ab le effectiven ess of atten ua tion . MN A toolb ox w as de si gn ed to be us ed w ith th e US De pt . of E nergy ’s gu id elin es for im pl em en tin g m on itored n atu ral atten ua tion . http ://www. san di a. gov/eesector/gs/gc/n /m na ho m e.ht m l F/ S PL US EPA Re gi on 5 F /S Pl us ( ve rs io n 1.5) is a s ta nd-al on e software th at d isp lay s an d allows an aly ses of 2D a nd 3D da ta . F/ S Pl us c an pe rf or m s m any o f t he s am e f unc tio ns a s FI EL DS T ools for A rcV iew © , i nc ludi ng da ta qu ery in g, visu alization , in terp olation an d volu m e estim ation . http ://www. tiem. ut k. ed u/ ~f ield s/

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A FCEE MAROS i s a de ci si on s uppo rt to ol us ed to de velop an op tim ization p lan for th e cu rren t m on itorin g sy stem in ord er to efficien tly ach ieve th e term in ation of th e m on itorin g pr ogram . I t is b ased on statistical m eth od s ap plied to site-sp ecific d ata th at accou nt s for re le va nt c ur re nt a nd hi st or ic al s ite da ta a s well as h yd rogeologic factors an d th e location of p oten tial recep tors. http ://www. gsi-ne t.com /software/Maros. htm undw at er Se ns itiv ity API T he Gro undw at er Se ns itiv ity To ol kit w as de sign ed to h elp site m an agers, water pur ve yo rs a nd r eg ul at or s e va lua te th e se ns itiv ity o f a g ro undw at er re so urc e to a po te nt ia l r el ea se o f c om po unds o f c onc er n (e .g ., a n MTBE-oxy ge na te d f ue l) a t a pa rticu lar site. T he toolkit ru ns on Microsoft E xcel ™ an d comes with a u ser’ s gu id e. http ://www. gsi-ne t.c om /s oftw are /Gro undw at er y. ht m D T reat O S M & states A M D T reat is a comp ut er ap plication for estim atin g ab atem en t costs for p ollu tion al m ine dr ai na ge , c om m onl y r ef er re d t o a s Ac id Mi ne Dr ai na ge o r AMD. AMDTr ea t can assist a u ser in estimatin g costs to ab ate water p ollu tion u sin g a variety of p assive an d ch emical treatmen t ty pe s. http ://amd treat. osmre. gov/amd son E ttin ger el E P A A series of m od

els for estim

atin g in door air con cen tration s an d associated h ealth risks from su bs urface vap or in tru sion in to bu ild in gs, b ased on th e an aly tical solu tion s of J ohns on a nd Etting er (2001) fo r con tam in an t p artition in g an d su bs urface vap or tran sp ort in to b uild in gs. http ://www. ep a. gov/su pe rf und/ /risk/airm od el/j oh ns on _e ttin ger.

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Decision Support Tools

HSSM EPA H SSM s im ul at es f lo w o f t he L NAPL pha se an d tran sp ort of a ch em ical con stitu en t of th e LN A P L from th e su rface to th e water tab le; rad ial sp read in g of th e LN A P L p ha se at th e w at er ta bl e, a nd di ss ol ut io n a nd a qui fe r tran sp ort of th e ch em ical con stitu en t. http ://www. ep a. gov/ad a/csmos/mod ss m w in.ht m l R A T E P A R egion 5 R ap id assessmen t T ools (R A T ) p rovid e in tegrated d ata retrieval, geograp hi c po sition in g sy stem (G P S ), geograp hi c in form ation sy stem , (G IS ), m ap pi ng an d an aly sis tools th rou gh a sim ple y et rob us t in terface th at req ui res n o p ost p rocessin g of GPS a nd GI S da ta . (h ave con tacted th e d evelop ers ab ou th is) On-S ite EPA O n-Si te w as de ve lo pe d t o pr ov ide m ode le rs an d mod el reviewers with p rep ackaged tools (“ calcu lators”) for p erform in g site assessmen t calcu lation s, stan da rd ized con tamin an t ch aracteristic d ata (in clu di ng da ta on fu el com position an d m od els for leach in g from fu el len ses) an d simp le an aly tical m od els th at allow th e u ser to test th e effects of u ncertain ty in p aram eter estim ates on m od el p red iction s. http ://www. ep a. gov/ath en s/learn 2m pa rt-two/on site/

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e E P A S crib e is a software tool d evelop ed to assist in th e pr oc es s o f m ana gi ng e nv ir onm en ta l da ta. S crib e cap tu res sam plin g, ob se rv at io na l, a nd m oni to ri ng f ie ld da ta . Exa m pl es o f Sc ri be f ie ld t as ks in cl ude So il S am plin g, Water S am plin g, A ir S am plin g and Bi ot a Sa m pl in g. Sc ri be c an im po rt electron ic d ata in clu di ng A naly tical Lab R esu lt d ata (E D D ) an d S am plin g Location da ta s uc h a s GPS. Sc ri be s uppo rt s ha ndhe ld ex ten sion s, Sc ri bl et s , to cap tu re an d im po rt sam plin g an d m on itorin g d ata collected on ha ndhe ld PDAs . http ://www. erts uppo rt .o rg /s cr ht m

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DST-11

EPA

Example Screening Level DST:

BIOSCREEN

Notes:

• BIOSCREEN is a tool originally developed to evaluate the efficacy of remediation by natural attenuation (RNA) at Air Force fuel spill sites. BIOSCREEN was developed by researchers from Rice University in conjunction with the Air Force Center for

Environmental Excellence (AFCEE). Because it is closely linked to AFCEE’s protocol for the evaluation of MNA at fuel sites, it provides an excellent example of a DST that compiles expert knowledge into a “stored process.”

• The BIOSCREEN input screen is an Excel worksheet where the user enters information on site hydrogeology, soil and chemical properties as well as plume dimensions. Given a set of parameter values and plume dimensions, the model calculates hydrocarbon

concentrations along the plume centerline in order to answer the question “how far will the dissolved contaminant plume extend if no engineered controls or further source zone reduction measures are implemented?”

• BIOSCREEN simulates degradation of petroleum compounds by both aerobic and anaerobic organisms. BIOSCREEN can be used for two different types of applications.

S As a screening model to determine if RNA is feasible at a site

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“scope” a potential remedy, such as RNA, before committing significant resources to implementing a thorough investigation of its potential applicability. To implement BIOSCREEN in the screening mode, the project team should collect a suite of geochemical analyses from a few wells inside and outside of the impacted area. Literature values can be used for most of the remaining parameters at this stage in the investigation. If RNA appears feasible, these parameter values can be refined through investigation before running the model again.

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DST-12

EPA

BIOSCREEN Output: Plume

Centerline

Notes:

• BIOSCREEN contains a first-order decay model and an instantaneous reaction model. AFCEE recommends the instantaneous reaction model for most sites. Geochemical indicator data are required to run the instantaneous reaction model. These data include concentrations of electron acceptors consumed in redox reactions (dissolved oxygen, nitrate, sulfate) and metabolic byproducts (ferrous iron and methane) generated from redox reactions.

• The output pictured above (as well as the input screen on the previous slide) is an actual model run from a screening level application of BIOSCREEN. The observed data is the black square representing the benzene concentration in groundwater near the bottom of the graph at a distance of 30 feet (along the plume centerline). The position of the square well below the red line (which represents predicted concentrations if NO biodegradation was occurring) indicates some biodegradation of benzene has likely occurred.

• However, the first-order decay model (blue line) was run with a conservative half-life that was at the very upper limit of the range of reasonable benzene half-life values

provided in the BIOSCREEN manual. Furthermore, the instantaneous model predicts the dissolved plume should disappear immediately downgradient of the source area, based on the biodegradation capacity of the aquifer (calculated from the difference in

concentration of electron acceptors and metabolic byproducts between background and in-plume wells).

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much slower rate than predicted by either model. Divergence between predictions and observations lead the project team to question why there is not better agreement. One possibility is that the concentration of one electron acceptor –sulfate – is so high (over 10,000 ppm) that it may inhibit, rather than enhance, microbial activity at the site. Thus, a new set of questions and hypotheses are used to further develop the CSM and will be evaluated during the development of active remedial alternatives (RNA having been ruled out).

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DST-13

EPA

FIELDS (FIeld EnvironmentaL

Decision Support)

The FIELDS system is a set of software modules designed to organize and analyze site and

contamination data FIELDS can be downloaded at: http://www.tiem.utk.edu/% 7Efields/ Notes:

• FIELDS requires ArcView 3.x and Spatial Analyst 1.1 or later. The most recent release of FIELDS allows VSP to be accessed as an ArcView extension. Thus, the VSP

sampling schemes can be run within FIELDS.

• FIELDS has robust graphical capabilities because it runs on an ArcView platform. Contours can be overlain on air photos or AutoCad base maps. AutoCad layers become individual “themes” in ArcView. Point, polygon and text themes may be turned on or off or overlain on one another. Custom layouts can be created and saved for each analyte or each area of interest.

• ArcView is a license-protected commercial software product that must be purchased from ESRI. A two-day training course in ArcView is recommended to become proficient in ArcView.

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DST-14 EPA

FIELDS Interface

Graphics View Plot Layout Notes:

• This slide shows the two types of ArcView user interface.

• The graphics view is the window in which data analysis is conducted. The map/graphics window in center and table of contents (TOC) at left are used in both ArcView and FIELDS. The toolbar at top has additional menu items specific to FIELDS on the right-hand side. If F/S Plus and VSP extensions are loaded, they will also appear on the toolbar.

• The TOC displays all of the themes that have been loaded into the view. All of the FIELDS tools and analyses require the user to select one or more themes in order to conduct the analysis. For instance, the contouring algorithms and sampling schemes generally require the user select a point theme (for data values) and polygon theme (to bound the analysis) in order to run. The results of most analyses and sampling tools (except adaptive fill) are automatically saved in a theme.

• The plot layout is used arrange plot elements (view, legend, title) for the plotting of maps and final products. The view window in upper right is incorporated into the plot layout in lower left in this example.

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DST-15

EPA

Spatial Analyst and Decision

Assistance (SADA)

SADA is an evolving

freeware product targeted

to individuals performing

environmental

assessments in support

of decision-making

SADA can be

downloaded at:

http://www.tiem.utk.edu/~

sada/

Notes:

• Spatial Analysis and Decision Assistance (SADA) is free software that incorporates integrated modules for visualization, geospatial analysis, statistical analysis, human health risk assessment, ecological risk assessment, cost/benefit analysis, sampling design, and decision analysis.

• The capabilities of SADA can be used independently or collectively to address site specific concerns when characterizing a contaminated site, assessing risk, determining the location of future samples, and when designing remedial action.

• A number of the capabilities present in SADA are also present in the FIELDS (Fully Integrated Environmental Location Decision Support) system.

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DST-16

EPA

SADA User Interface

Notes:

• The SADA user interface has three components: the graphics view on the left (where the maps and data plots are viewed), the control panel on the right (where the user selects parameters/enters data for sampling schemes, geostatistics, search neighborhoods and decision levels); and the menu/toolbar at the top of the view (where the user can select the type of map or plot with the buttons or choose between major program functions).

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DST-17

EPA

Mini Case Study: Using DSTs to Guide

and Communicate Project Decisions:

Marino Bros. Scrapyard Site

Brownfields site on banks of Ohio River PCOCs are metals and PCBs

Reuse plan: mixed commercial/recreational

The preliminary CSM was used to develop estimates of expected volumes of soil to be removed in order to clean up site for reuse. Two “comprehensive” level DSTs were used:

» FIELDS was used to query & contour data, identify “drivers” and perform bulk mass and volume calculations.

» SADA was used to contour data on a rectangular grid, estimate average concentrations and export estimated values in Excel spreadsheets for further calculations.

» A “do-it-yourself” DST was created using Excel spreadsheets to incorporate complex decision logic into cost estimating process.

Notes:

• The Marino Scrapyard site is a riverside Brownfields in western Pennsylvania. The scrapyard ceased operation in 1998. The local municipality now owns the site and wants to redevelop it for mixed commercial/recreational use. An RI was conducted by the Pennsylvania Department of Environmental Protection (PADEP).

• The principal media of concern are surface soil and subsurface soil to the approximate depth of the groundwater table (12 feet below ground surface). The targeted

contaminants of concern (COCs) for soil included seven metals and two polychlorinated biphenyls (PCBs). Site specific standards were developed for the COCs during a risk evaluation.

• EPA OSRTI’s Brownfields Technical Support Center was tasked to prepare a

preliminary CSM from the RI data and use the preliminary CSM to develop a dynamic work planning strategy and a statement of work (SOW) that PADEP used to guide an expedited site cleanup. The SOW provided the quantities (excavation volume and disposal volumes) for contractors to bid on.

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DST-18

EPA

FIELDS: Visualize/Communicate

Nature and Extent and Calculate

Bulk Removal Volume

Isoconcentration maps highlight areas of overlap, allowing project team to focus on a smaller suite of analytes.

Notes:

• EPA’s FIELDS was used to create high-quality 2D contour maps. Concentrations above site-specific, risk-based standards were contoured using the natural neighbor (NN) interpolation scheme in 2D. Results were plotted on an aerial photograph. Because FIELDS supports only 2D interpolation, the data were queried in 2-foot depth intervals to create “slice” maps. Comparison of maps representing successive 2-foot slices allowed a quasi-3D analysis of the data.

• The mapping exercise showed lead to be the most widespread COC and suggested that removal of lead above the site-specific standard would remove all other constituents that exceeded their site-specific standards. Thus, lead was used as an indicator COC for the purpose of performing volume calculations.

• FIELDS calculated the areas where lead exceeded the site-specific standard and

multiplied the areas by the two-foot thickness of each “slice” to arrive at the volume to be removed. The “Remediation Tool” function in FIELDS was used to calculated the total volume of soil to be removed. The total volume was used as a quantity for contractors to bid on.

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DST-19

EPA

SADA: Delineate Excavation Extent

on a Rectangular Grid and Export

Results

Contour Map

Area of Concern (AOC) Map

Estimated Depth of Excavation for Bidding Purposes

(graphic was created outside of SADA)

Notes:

• In terms of disposal, the biggest cost drivers were hot spots of mercury and PCBs, which have more stringent disposal requirements than lead. Specifically, the excavation volume needed to be subdivided into smaller volumes for disposal at different classes of landfills, based on land disposal restrictions, estimated toxicity threshold values (estimated using the Toxicity Characteristic Leaching Procedure [TCLP] 10X guideline) and specific criteria for local landfills.

• SADA provided a convenient interface to contour and export the data to an

Excel-compatible file format. Interpolated concentrations of lead, mercury and PCB congeners provided the basis for calculating the volumes of soil that would go to Class I or Class II landfills under various scenarios. SADA’s AOC module allows the user to highlight all cells where the average concentration exceeds a user-defined action level. Estimated concentrations (from the contour map) and AOC results (above or below action level) were exported from SADA to an Excel file. Further processing was conducted in Excel.

• Together, the two DSTs provided a variety of visualization, estimation (contouring) and delineation tools that were brought to bear on the analysis. Sufficiency of the CSM and its underlying data set was tested by contouring the data using both tools, comparing the results and conducting a sensitivity analysis to determine a range of remediation costs that encompassed uncertainty inherent in the CSM.

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DST-20

EPA

Verify Sufficiency of CSM

Notes:

• A key tenet in the Triad methodology is that data collection and analysis is driven by the need to mature the CSM until just enough data is collected and interpreted for the project team and stakeholders to make an informed decision about the site, whether it be the need for a remedy, the selection of a remedial alternative, or a decision regarding property ownership or development. The Triad methodology emphasizes planning for this decision point. The iterative nature of a Triad investigation allows for the project team to constantly reevaluate the CSM with each new round of sample collection and analysis. With each iteration, the CSM is tested, discussed and probed for weaknesses by the project team. DSTs provide a platform for this process.

• In the ideal Triad setting, the project follows each of the steps outlined in this module. Occasionally, the Triad approach is applied to data already collected and compiled and the Triad methodology is used to bridge the gap between a poorly-developed CSM and a concrete plan for remedial action. In the following example, the site’s remedial

investigation (RI) was more or less complete – at least in the eyes of project stakeholders. The CSM, as it was presented in raw form in the RI, did not provide a sufficient basis to estimate the cost of a planned removal action. The project stakeholders, therefore, needed tools and a method for interpreting the data to better develop the CSM, then deciding if the CSM was mature enough to guide planning and procurement for the removal action.