Category: Design & Cleanup

Train Derailment Spill Cleanup

Umatilla River – Pendleton, OR

Toluene Spill Cleanup

A train derailment near Pendleton, Oregon resulted in the release of 10,000 gallons of toluene in a farmer’s field within a few hundred feet of the Umatilla River. CRETE principals responded to the spill as part of an organized spill response program.

Due to salvage and mainline restoration activities, initial cleanup activities included interceptor trenches and limited pumping to prevent discharges to the river. Shortly thereafter, air sparging systems were installed in the open trenches to encourage soil and groundwater treatment. After initial response efforts, the air sparging groundwater treatment system was converted to a well point system to address impacts downgradient of the excavated source area.

The Umatilla River is designated as a “wild and scenic river” and fish populations were being reestablished by a joint effort of farmers (reducing irrigation water extraction), the Umatilla Indian Tribe, and various state agencies. In the two weeks leading up to the spill, about 2,000,000 smolt had been released to the river. Recognizing these issues, an aquatic biologist was flown to the site, where they coordinated daily meetings with the Department of Fish and Wildlife, the Umatilla Indian Tribe, the EPA and other interested parties, and allowed these parties limited access to the site.

The site was cleaned up within 8 months and delisted within 2 years. Costs were reduced by avoiding claims and fines, limiting long-term operations and monitoring of remediation systems, and by managing the excavated source area soil “on site.” Total costs savings were in excess of $3 million.

Work Performedproject_upspill2

  • Regulatory negotiations – DEQ, EPA
  • Upland RI/FS
  • Petroleum upland cleanup
  • Construction oversight
  • Insurance cost recovery

Value Added

  • Rapid response prevented discharges to the river and prevented fines and resource damage claims
  • Prevented fiber-optics line failure due to chemical compatibility issues
  • Appropriate definition of the “site” allowed on-site treatment of listed wastes
  • Treatment of U220 listed soil avoided incineration and allowed use of soil as clean fill
  • Treatment of U220 listed groundwater allowed reuse for irrigation
  • Cleanup of the site occurred within 8 months and the site was delisted within 2 years
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Phase I ESAs and Design Support

Municipal Utility Upgrades – Burien, WA

Burien Street Pic CRETE principals subcontracted to a civil engineering firm to perform a Phase I environmental site assessment associated with the design of a significant utility and right-of-way enhancement project. The project was for a 2-mile stretch of a commercial business district with stormwater outfall to a salmon-bearing stream. The purpose of the assessment was to determine and map all known and suspected soil and groundwater impacts along the project. Based on the assessment, the following modifications were made to the utility design plan:

  • Electric utility vaults were relocated to avoid areas with possible explosive vapors
  • Storm drains that intercepted groundwater were backfilled with controlled density fill to avoid creating preferential pathways for contaminated groundwater flow
  • Storm drain installation plans were modified to include above-grade welding of HDPE pipe and rolling of the storm drain into the trench to limit dewatering of contaminated groundwater and control unnecessary worker exposure to contaminants

CRETE principals developed specifications in accordance with Washington State Department of Transportation (WSDOT) format related to environmental aspects of the project including soil segregation and stockpiling, construction stormwater and groundwater management, and soil and water treatment or disposal. After award of the construction contract, CRETE principals continued to work on the project to assist with:

  • Contained-in determination approaches to manage and sample solvent-impacted soil
  • Local sewer company discussions to allow discharge of petroleum- and solvent-impacted groundwater from excavations

Work PerformedBurien Backfill

  • Property assessment due diligence
  • Regulatory negotiations – MTCA
  • Permitting – construction stormwater, POTW discharge
  • Development coordination
  • Construction plans and specifications
  • Stormwater system design

Value Added

  • Relocated utility vaults to allow future utility maintenance without vapor mitigation
  • Developed a modified stormwater pipe design and installation technique to minimize site dewatering and water treatment costs and to limit the exposure of workers to hazardous materials
  • Modified the stormwater pipe backfill design so that the project did not result in preferential migration of contaminated groundwater
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Urban Park Cleanup

Former Manufactured Gas Plant – Seattle, WA

GWP from EastCRETE principals performed cleanup and restoration of an urban park and prepared an RI/FS for the lake sediment. The 25-acre public park was created in the mid-1970s and retained many of the former industrial structures.

The upland remedy included tar removal, soil capping, an air sparging system along portions of the shoreline to remove benzene from shallow groundwater that discharges to the lake, and upland and shoreline habitat restoration. The selected remedy allowed continued use of the park without significant disruption. Design of the remedy was negotiated with numerous stakeholders included Seattle Design Commission and Historic Landmarks Board. Features such as a Corten steel equipment enclosure were used to maintain the historical aesthetic, and the cap design maintained the land sculpture topography of the park. MTCA remediation levels for PAHs and benzene were negotiated such that the air sparging system met performance criteria in 2 years.

CRETE principals analyzed the range of cleanup approaches for sediment. Probabilistic cost modeling provided a likely range of cleanup costs which were used in insurance cost recovery negotiations.

CRETE was involved in preparation of a draft RI/FS for the cleanup and restoration of subaqueous sediment and the adjacent shoreline. Historical MGP, shipyard, and other industrial operations impacted the sediment with PAHs, metals, and other contaminants. CRETE principals helped develop soft-sediment capping solutions that are resistant to frequent boat wake erosion and offer habitat value. Cap design included fate and transport modeling of PAHs through sediment to determine cap thickness and in situ strength testing to determine a suitable method for placing cap materials on very soft sediment because traditional laboratory strength tests did not provide accurate in situ sediment strength data. Capping challenges also include consideration of sub-aqueous slope stability under both static and seismic conditions.

Work Performed

  • Regulatory negotiations – MTCASnapshot 1 (1-29-2013 9-21 AM)
  • Permitting – design commission, historic landmarks
  • Shoreline site cleanup and development integration
  • Construction management
  • Insurance cost recovery
  • Sediment RI/FS
  • Geotechnical analysis of sediments
  • Sediment cap design

Value Added

  • Negotiated remediation levels based on groundwater to surface water attenuation factors
  • Completed cleanup of the park during the winter and successfully reopened park for July 4th celebration
  • Incorporated design features, such as the use of corten steel, to satisfy the Design Commission and the Historic Landmarks Board
  • Successfully demonstrated the ability to cap very soft sediments
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Urban Infill Condominium

Former Car Dealership – Seattle, WA

Canal Station was once the site of theproject_canalstation_lrg New Wilson Ford car dealership. Although car dealership activities led to certain environmental conditions (leaking UST and abandoned oil-water separator), the primary environmental concern at the site was a chlorinated solvent groundwater plume originating off-site.

The property was purchased to construct a mixed-use condominium building. The first phase was built on the clean parcel; the second phase was built on the parcel with impacted groundwater . CRETE principals developed the cleanup approach and negotiated a technical opinion letter with Ecology through the Voluntary Cleanup Program (VCP).

The groundwater remediation system consisted of a segregated under-slab groundwater collection system designed in conjunction with the building civil design and fully integrated into the development. Impacted groundwater is collected in a separate vault and is discharged to the sanitary sewer. A contingency for treatment of the groundwater was designed into the underground parking structure, but the contingency has not been triggered.

CRETE principals directed all aspects of the project, including:

  • Phase I and Phase II site assessments
  • Cleanup Action Plan preparation and review with Ecology
  • Quarterly groundwater monitoring prior to construction
  • Under-slab groundwater drainage system design
  • Construction dewatering discharge authorizations from Metro King County and associated sampling and reporting
  • Environmental cleanup construction oversight (i.e., removal of a leaking heating oil tank; removal of an oil-water separator containing dangerous waste)
  • Excavation oversight and associated sampling

Work Performed

  • Property transaction due diligenceCanal Station manhole
  • Regulatory negotiations – MTCA VCP
  • Permitting – construction stormwater, Metro discharge
  • Site cleanup design and redevelopment coordination
  • Construction plans and specifications
  • Construction oversight
  • Construction stormwater management

Value Added

  • Segregated and sampled soil so that most was sent off site as clean material
  • Negotiated a technical opinion letter with Ecology
  • Fully integrated the groundwater extraction system with development
  • Designed and negotiated discharge to the sanitary sewer to minimize costs
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Landfill and Stormwater Upgrades

Steel Mill Expansion – Portland, OR

An existing steel mill was looking toEVRAZ landfill expand operations by constructing a large pipe rolling mill on their property. In order to make the planned new pipe rolling mill work efficiently, rail service to the mill needed to be rerouted into the location of two existing inert material landfills. At the same time, the mill was involved with the agency to undergo a voluntary source control process to limit their input into the Portland Harbor Superfund Site. CRETE principals provided engineering, environmental, geotechnical and permitting services to modify the two solid waste landfills and managed design and construction of end of pipe stormwater treatment as a source control measure on the site.

Landfill relocation was complicated by the requirement that the project be designed and permitted with the State agency, and bid and constructed within a year to accommodate the aggressive schedule for getting the proposed new pipe rolling mill online to meet order demands. Landfill reconstruction was completed within the tight time frame required and within the allotted budget for the work.

Stormwater system upgrades were implemented to be consistent with source control for the ultimate environmental cleanup of the site. The program’s design and implementation was an interactive process with Oregon Department of Environmental Quality (DEQ) and it was executed while maintaining and accommodating key mill operations. The end-of-pipe stormwater treatment system includes wet well collection areas near former outfall discharge points, chemical treatment, pump stations to transport treatment water to a settling basin, and discharge back to existing outfall after solids settle in the basin. The remaining two stormwater basins were addressed with stormwater BMPs and infiltration.

Work Performed

  • Regulatory negotiations – DEQEVRAZ Storm Pipe
  • Geotechnical analysis and reporting
  • Permitting – solid waste, wetlands, grading, construction stormwater
  • Site cleanup and development coordination
  • Construction plans and specifications
  • Construction oversight
  • Stormwater system design

Value Added

  • Negotiated off-site wetland mitigation to provide an adequate development footprint
  • Completed permitting on a very tight time schedule by amending mill permits
  • Performed geotechnical analyses of the rail bed and landfill on the same tight schedule
  • Completed all work on schedule to allow mill expansion
  • Designed stormwater system to criteria more stringent than local codes to address potential contribution to the Superfund site
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Lake Washington Brownfield

Former Wood-Treating Plant – Renton, WA

CRETE principals led the investigation and project_sports-fields-aerialcleanup of this brownfield redevelopment project at a former wood-treating site on Lake Washington. CRETE principals completed the RI/FS, Cleanup Action Plan, Consent Decree, Engineering Design Report, and design plans and specification for cleanup of the property. Remediation on the property consisted of:

  • In situ soil mixing of source area soil and NAPLs with cement and bentonite
  • Sediment removal from a cove and restoration of a forested wetland
  • Soil capping that was fully integrated with site redevelopment
  • Relocation of a salmon-bearing stream
  • Development of site-wide stormwater management program

In situ soil mixing was implemented because geotechnical constraints at the site made excavation impractical. A cement-bentonite additive was designed to reduce the hydraulic conductivity of the impacted soil, thus restricting contaminant transport to the lake. The additive was also formulated such that the soil-additive mixture exhibited strength similar to that of the native soil. Matching native soil strength allowed flexibility in the use of foundation piles for future site redevelopment. The mixed soil was reused on-site to reduce cleanup costs.

Extensive areas of peat and other organic debris generated methane at the site. Methane mitigation systems were designed and installed in the headquarters building, indoor practice facility, and maintenance building.

CRETE principals managed the sediment remediation and wetland restoration of the cove. A one-acre emergent marsh on Lake Washington was restored to provided resident turtle habitat.

The Engineering Design Report provided adequate flexibility in schedule and cap design scenarios for the final redevelopment design to be regularly adjusted while complying with Washington State Department of Ecology requirements. The capping options included asphalt parking areas, pile-supported structures, football fields constructed of natural and artificial turf, and support areas for maintenance, emergency response, and public viewing.

CRETE principals worked with other design team members to develop a stormwater management system consistent with the 2005 King County Surface Water Design Manual. The design efficiently utilized the limited land space by infiltrating rain water through 18 inches of sand in the football field subgrade, thus satisfying the enhanced treatment requirement for discharge to the lake without using land space for a separate enhanced treatment facility. An integrated pest management plan outlines best management practices for the selection and application of turf amendments to minimize the off-site transport of pesticides and fertilizers. The design also included the use of grassy swales around the parking lot sand filters to satisfy the pretreatment requirement. The stormwater outfalls were also designed to avoid the need for USACE permitting. CRETE principals also provided construction oversight including construction stormwater collection and treatment with carbon dioxide and chitosan prior to discharge to the sanitary sewer.

The final phase of the cleanup action (environmental capping and institutional controls) was completed in 2008 in conjunction with redevelopment activities.

Work Performed

  • Property transaction due diligence
  • Regulatory negotiations – MTCA
  • Upland and sediment RI/FS
  • Permitting – in-water cleanup, wetlands, stream relocation, construction stormwater, Metro discharge
  • Sediment cleanupSeahawksSoilMixingOverview
  • Wetland restoration
  • Shoreline site cleanup and development coordination
  • Methane mitigation systems
  • Construction plans and specifications
  • Construction stormwater treatment
  • Construction oversight
  • Stormwater system design

Value Added

  • Negotiated that RCRA F-waste listings did not apply to soil and groundwater
  • Used physical criteria to minimize the volume of K001 listed waste
  • Negotiated a flexible cleanup schedule to allow coordination with development
  • Created a menu of environmental cap designs to allow multiple site development scenarios
  • Developed the CAP to allow grading and reuse of contaminated soil on site
  • Designed in situ soil mixing of source soil and NAPLs to contain source material due to geotechnical constraints
  • Designed the in situ soil mix to provide a final mix strength similar to that of soil to maximize flexibility in the use of foundation piles for various redevelopment scenarios
  • Integrated enhanced stormwater treatment features, including sand filters and pretreatment, within the environmental caps to maximize the development footprint
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