Site Background - SWIX Proceedingsproceedings.swix.ws/2005_10_09_Brownfields/content/pdf/Jansen.pdf... (ACOE) – Dredge and Fill ... Design and Construction Challenges ... Piggy back

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Unique Challenges Related toMarina Brownfields Development

St. Augustine Case Study

Presented to

2005 Florida Brownfields ConferenceOctober 11, 2005

Proprietary and ConfidentialThe RETEC Group, Inc.

Site Background Site Operations

Manufactured gas plant from 1885 intothe late 1950s

Produced and distributed gas for lightingand heating

Ownership Atlanta Gas Light Company &

predecessors from 1885 to 1989

City of St Augustine from 1989 until 2005

Currently: San Sebastian Partners

Liability Owners Atlanta Gas Light Company holds Majority

Share

City of St. Augustine holds Minor Share

Two Distinct Phases of Work

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Regulatory Setting

EPA Region IV Superfund Program Engineering Evaluation/ Cost Analysis (EE/CA) – Accelerated Investigation and

Feasibility Process

Administrative Order on Consent

Work Performed Under a Removal Action Army Corps of Engineers (ACOE) – Dredge and Fill Permit – Key component for both

phases of work

Other Regulatory Agencies Involved NOAA, FDEP, US Fish & Wildlife, SJWM

Expedient review of documents allowed for a compressed

schedule

Phase I - 2001 Removal Action

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Objectives for Phase I

Remove soil to cleanup levels protective offuture construction workers that will performredevelopment work

Source removal to manage groundwater impacts

Tools used to meet objectives: Vertical Cut-line

30 feet source zone, 8 feet uplands, 3 feet marsh

Horizontal Endpoints Locate engineering controls beyond horizontal

limits of impacts identified in investigation

Institutional controls and restrictive covenants Restrict use of groundwater

Post remediation HASP to protect futureconstruction workers

Site Plan forRemediation


Technical Challenges

Large environmental earthwork project

Sequence excavation and transport of 85,000 tonsof coal tar-impacted saturated zone soil on achallenging downtown site

Deep excavation into a shallow groundwater table Excavation in a tidally influenced marsh adjacent to

a river

Rain – Hurricane season

Air monitoring protective of community

Temporary marsh restoration/replanting

Work was performed on an Aggressive Schedulewith a tightly controlled budget

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Design and Construction Challenges Two Cofferdams

Dam the River

Support Riberia Street and a 30 foot excavation Factors of safety- withstand 15-inch rainfall in 24 hours

Choreographed sheeting installation with utilityshutdowns

Pump Tests - Dewatering System Two stage wellpoint system 120 wellpoints and 8 deep

dewatering wells

Complicated geology - permeable shell hash, Overlainby clean sand, a clay aquitard, and fine silty sands toground surface

Logistics Traffic, decontamination, confirmation sampling,

stormwater control, flooding, demolition, asbestos, andunderground obstructions


City of St. Augustine –In Kind Services and Partner

Initial Cost Share Agreement – cost basis for inkind services

Backfill

Water Treatment – 400K gal/day by POTW

Traffic Control Invaluable logistical support from the City Manager’s

Office

Collaboration of Phase I partners built

momentum for Phase II success

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Stakeholder Challenges for Phase II –The Marina Development

Convert a vacant water front parcel into amixed use residential, retail and marinadevelopment

Fulfill the continuing obligations of the Order

Meet EPA’s expectations from aninvestigation design and implementationperspective

The Team succeeded due to the

collaboration of Stakeholders in a

give and take process with willingness toaccept some risk

to assure successof the deal


REDEVELOPMENT

Regulat

ors

Propert

y Owner

(City

of St. A

ugustine)

Development Team

Responsible

Parties

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Technical Team—Focal Point forthe Collaborative Process

RETEC ensured that the technical details met the goals of the regulatory, legal anddevelopment teams

Provide a transparent technical vision to manage environmental components in anunderstandable manner

Investigation – Pre-sampling 3-D modeling from investigation boring logs:

Lithological contouring

Chemical contouring that associates impacts with types of soil

Supports a cutline approach based on analytical results

Visual observation during remediation


Liability Management Processfor Redevelopment

Legal Teams balanced risk for theirindividual clients and created contracts toestablish financial responsibility for majorcost components

Melding of legal and technical inputs intolegal documents Provides a framework for a thorough and

collaborative identification of the risks andliabilities – who is responsible for what

Legal documents are Three PartAgreement and Cost AllocationAgreement

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Three Party Agreement

Identify the party responsible for managing the individual elements of the workfor major components such as: Environmental work plans and design verses marina design and construction

Environmental oversight to assure compliance with the Order

Permits and licenses

Transportation, disposal or reuse of soils

Established a clear enforceable contract: Mutual Release

Indemnification

Insurance


Cost Allocation Agreement

Identifies who pays for what based on incremental cost of environmental workvs “clean” civil work

RETEC’s Role Develop technical specifications for excavation, material management, segregation of

different classes of soil, and transportation and disposal

Plans with sequenced cut-lines in 3-foot horizons

Define impacts remaining at vertical limits Over excavate 2 feet, or

Install scour resistant cap

Technical graphic representation of the environmental work facilitated an understanding of the incremental cost

of a marina development with environmental impacts

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Cost Negotiations and Economic Balance

RETEC and legal team conceptualized a unit cost approach

Development team used a lump sum bid approach

$500,000 Divergence in expected cost from bids vs. Engineers Estimate Utilized subcontractor interviews and information exchange to narrow the cost

gap to less than $50K from the Engineer’s Estimate

Maximize sequencing to gain benefits from “Clean” Contractor Piggy back cofferdam construction with entrance channel dredging – minimize

mobilization fees and maximize volume of work by a single contractor


The Collaborative Effort Allowed the Teamto Overcome Various Challenges

Clear regulatory leadership from EPA and other agencies includingNOAA, the Corps of Engineers, and FDEP

Financial backing from AGLC, the City, and the San SebastianPartners

Legal expertise which provided a contractual relationship toperform the work

Technical leadership to satisfy the requirements of the AOC andgain approval from EPA

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Regulators

EPA

NOAA

Corps of Engineers Permit Modification

SJWMD

FDEP

Ensure compliance with the order whileapplying the cleanup criteria to the sitespecific details of the redevelopment

Construction Worker Risk – 2001 RA

Ecological Risk – 2005 Marina Work –Continuing obligation from the Order Ecological receptors at the new base

elevation of the marina

Probable Effects Level and ThresholdEffects Level


Development Team –San Sebastian Partners

Development Partners

Legal

Architect

Financial Institution Construction Manager/GC

Environmental Consultant

Engineering Marine

Geotech

Surveying

Structural

Remediation Contractor and Subs

Marina and Construction Contractors

Conceptualized the harbor and sitedesign

Establish the parameters for thetechnical team to plan a secondphase of investigation

Design and remediation for the marinadevelopment

Without the developers vision for the site,redevelopment could not occur

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Property Owner (City of St. Augustine)

City Manager

City Council

Public

Legal

Public Works/Engineer/Other

Business Community


Responsible Parties

AGLC

City of St. Augustine

Legal

Environmental Consultant Driller

Laboratory

Landfill

Manage environmental liability throughout theredevelopment project while doing the rightthing as corporate/municipal stewards

Understand implications of technicaldecisions in the investigation and designprocess and their impact to risk and cost

Work within budget and schedule constraints

The objectivity, knowledge, and trust in the technical approachwas a key towards successful development

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Figure 2-3a: Site Lithology at 0 feet NGVD

Sandy fill (blue)

Silty clay muck (red) Silty clay (aqua)Fine to mediumsand (light green)

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Figure 2-3b: Site Lithology at -1.5 feet NGVD

Sandy fill (blue)



Figure 2-3c: Site Lithology at -3 feet NGVD

Sandy fill (blue)


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Figure 2-3d: Site Lithology at –4.5 feet NGVD

Sandy fill (blue)



Figure 2-3e: Site Lithology at –6 feet NGVD

Sandy fill (blue)


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Figure 2-3f: Site Lithology at –7.5 feet NGVD

Sandy fill (blue)

Silty clay muck (red) Silty clay (aqua)

Fine to mediumsand (light green)

Clayey sand (green)


Figure 2-3g: Site Lithology at –9 feet NGVD

Sandy fill (blue)

Silty clay muck (red) Silty clay (aqua)


Clayey sand (green)

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Figure 2-3h: Site Lithology at –11 feet NGVD

Silty claymuck (red)

Silty clay (aqua)


Clayey sand (green)


Figure 2-3i: Site Lithology at –13 feet NGVD

Silty claymuck (red)

Silty clay (aqua)


Clayey sand (green)

Sandy clay (gold)

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Figure 2-9a: Benzo(a)pyrene impact at 0 feet NGVD and above

contour levels at 72, 720, and 7200 ug/kg

72

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Figure 2-9b: Benzo(a)pyrene impact at –1.5 feet NGVD


72

72

72

72720

72


Figure 2-9c: Benzo(a)pyrene impact at -3 feet NGVD


72

720

72

72

720

720

72

72

72

72

72

720

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Figure 2-9d: Benzo(a)pyrene impact at –4.5 feet NGVD


720

720

720

72

72072

72072

72

72

720

7200


Figure 2-9e: Benzo(a)pyrene impact at -6 feet NGVD


720

72

72

720

7200

7207200

72072007200

720

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Figure 2-9f: Benzo(a)pyrene impact at –7.5 feet NGVD


72

720

720

720

720

72


Figure 2-9g: Benzo(a)pyrene impact at -9 feet NGVD


72

720

720

72

720

72

72

72

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Figure 2-9h: Benzo(a)pyrene impact at -11 feet NGVD


72

72

720

72

72


Figure 2-9i: Benzo(a)pyrene impact at -13 feet NGVD


72

72

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Documents

Site Background - SWIX Proceedingsproceedings.swix.ws/2005_10_09_Brownfields/content/pdf/Jansen.pdf... (ACOE) – Dredge and Fill ... Design and Construction Challenges ... Piggy back