Case Studies

Lead content soils

 

Type: Excavation
Contract Value: $1,400,000
Period | Location: June-August 2013 | Byram Township, NJ
Work Areas: Lead soil excavation, culvert pipe, groundwater treatment and disposal, wetland restoration and mitigation program.

 

EWMI conducted a Lead Waste Fill and Sediment excavation along a prestigious lake in Sussex County, NJ. EWMI deployed a temporary aqua dam to hold back water and dewater inside the barrier to safely excavate Hazardous Lead sediment at the outfall of a culvert pipe. A large portion of the excavation commenced in a very small parcel along a winding, busy, rural roadside. Approximately 5,000 tons of high lead content soils were excavated, loaded and transported to multiple approved facilities. During the course of excavation, EWMI became challenged with high volumes of infiltrating ground water as we approached the lake’s shoreline. EWMI mobilized a carbon, and filtration groundwater treatment system to dewater, treat and containerize the liquids. The water was sampled, and either discharged or disposed of at approved facilities. Due the sites very tight space constraints, EWMI successfully transported soils and liquids with little or no impact to daily travelers on this busy roadway. EWMI procured, and placed NJ DEP approved wetland mixture topsoil and plantings and provided a multi-year maintenance monitoring plan.

Sandy soil engineered excavation

 

Type: Excavation
Contract Value: $2,600,000
Period | Location: Early 2013, 5-month project | Connecticut
Work Areas: Engineered excavation, dig and haul, transportation and disposal, backfill and compaction, and strict schedule compliance.

 

This large scale excavation involved sandy soil conditions to depths of 50 feet. Both shoring and sheeting as well as benching were proposed by EWMI. Ultimately, benching was chosen over driving sheeting for multiple reasons. EWMI, with an independent engineer, designed an excavation plan to safely bench the proposed excavation to remove approximately 18,000 tons of contaminated soils. Total soil movement and management involved 80,000 tons.

 

The final excavation was a massive excavation with engineered slopes per the plan (see pictures below). Certain walls/floors exceeded the site clean up plan and further “chasing” of some areas was also required. Multiple excavators and articulating dumps were necessary to meet the time schedule for an excavation of this size. Backfilling of the area(s) was completed using 12” lifts and subsequent proof rolling. All transportation and disposal was managed and completed by EWMI. Two (2) disposal facilities were utilized due to the aggressive schedule and truck volume production required per day. All soils managed by EWMI were non-hazardous and went to beneficial reuse/recycling facilities.

Sub cellar chlordane trenching

 

Type: Excavation
Contract Value: $400,000
Period | Location: June-September 2013 | Manhattan, NY
Work Areas: Concrete breaking, hazardous soil excavation, underpinning, and wood lagging excavation support.

 

After a catastrophic fire severely damaged a New York City Synagogue in 2011, restoration and rebuilding included the discovery of pesticide impacted soil under the building’s existing concrete floors. After a year of design and permitting, EWMI was called in to manage impacted soils during a mass underpinning and structural rehabilitation program. EWMI would excavate, handle and dispose of impacted soil in all areas where historic foundation upgrades would take place. All soils had to be gridded out and planned carefully to remove and dispose of Chlordane impacted soil. All while critical, time sensitive and ongoing construction with other trades was commencing. Large, buried granite blocks and brick footings from historic foundations had to be cut, broken and removed where pile cap excavation and installation were planned. A strict summer schedule had to be met while the children were on break from the adjacent School. Each wheel barrow of soil had to be covered with plastic and carefully maneuvered out of the basement, through freight elevators, across active city sidewalks, and to the roll-off containers staged in the street one load at a time. Since it was a mass construction project in New York’s busy streets, each roll-off from four different waste streams had to be carefully planned to avoid interruption with adjacent building tenants, and other trades during construction. EWMI saved our client money with gridding out the soil and surgical excavation in multiple layers according to its pre-characterized soil borings.