Investigation & Remediation

Case Study: Environmentally Sustainable Remediation in a Wetlands Ecosystem

MP&A has a long history of remediation work for legacy oil and gas sites. At a large site in a wetlands environment in south Louisiana, MP&A designed a remedy to restore function to wetlands areas and meet remedial goals through onsite treatment of contaminated soil. The program consisted of construction of land treatment cells where soil was treated through aeration and addition of amendments to reduce contaminants. Approximately 25% of the contaminated soil identified for remediation on site was treated using this method. Other contaminated soil was identified for offsite disposal due to elevated levels of contaminants. 

During the planning phase of the project, MP&A identified a land disposal facility that was significantly closer to the project site than the nearest E&P waste facility. To achieve approval for the project, the waste management company required additional documentation including a written waste characterization program. MP&A provided all the required documentation to the waste management company and assisted in the process of obtaining the required approvals, thereby reducing the transportation costs and overall carbon footprint for the project.

Case Study: Environmentally Sustainable Oil Field Remediation

MP&A conducted a very large oil field cleanup project in north Louisiana which included:

  • Registration and closure of 62 pits and other areas (i.e. tank batteries)
  • Plugging and abandonment of four oil & gas wells
  • Removal of 20 concrete pump jack slabs
  • Removal and offsite disposal of over 9,000 cubic yards of oily soil
  • Removal and offsite disposal of 4,000 barrels of onsite water
  • Pipe and oilfield debris removal

MP&A retained and managed a local contractor who conducted the work from 2010 to 2015 at a total cost of approximately $3.5 million. The majority of the pits were closed by backfilling with former berm material that met Statewide Order 29-B Louisiana Department of Natural Resources standards.

Case Study: Environmental Investigation and Remediation of Onsite Arsenic

MP&A provided turn-key design, regulatory approval and construction/construction management services to assist a worldwide pharmaceutical company in resolving obligations to remediate four former cattle dipping sites in Louisiana. These sites were used in the 1920s - 1960s to combat Cattle Tick Fever. The constituent and media of concern was arsenic in soil. Remediation was completed by excavation and offsite commercial disposal of contaminated soil. MP&A utilized an XRF instrument to field screen soils for arsenic to minimize over excavation of clean soils and to control costs.  MP&A also utilized boards to construct temporary roads to access each site. MP&A worked with each landowner to define and satisfy their site specific needs and scheduling limitations. Project was performed within budget and schedule.

Restoration

Case Study: Innovative Remediation

MP&A designed a restoration plan for a former oil and gas exploration and production facility located in the coastal zone in an area accessible only by boat via a system of canals. We designed investigation and remediation procedures using barges and tugboats that could travel the canal system without disturbing the rich sediment ecosystem, hand tools instead of heavy construction equipment when possible, and booms, silt curtains and sheet pilings to reduce impact to the adjacent waterway. Impacted soil and sediment was excavated using barge-mounted equipment and placed in barges for shipment to the permitted disposal facility. Restoration of the site was performed by completing a detailed inventory of pre-remediation site conditions, performing surveys to determine the locations and elevations of the existing bank line, backfilling the excavated area with clean backfill and re-vegetating the area. In order to mimic the existing ecosystem, MP&A defined a zone of clean overburden soil that was reused as topsoil to support the same species of plants that existed before the remediation began.

Case Study: Habitat Restoration

MP&A designed and implemented a phytoremediation project for a CERCLA Superfund site.  The site is located in a residential area and nearby residences have historically been party to litigation against the responsible parties.  The phytoremediation included tree plantings, which were implemented in phases.  The initial plantings established that proven phyto-tested species could survive in site soils and later plantings were conducted to expand into other areas of the site and incorporate more native tree species. 

In areas of the site where there was heavy soil compaction, the project included a significant effort to restore soil health including addition of mulch, fertilizer and earthworms.  The project team included experts in the area of phytoremediation and specialists to assist with maintenance of the plantings.  The monitoring program includes periodic tree growth measurements and tree coring which has confirmed uptake of site contaminants.  The site has been converted from open pits and tanks to an open grass-covered field and forested area where local students are escorted for field trips.

Case Study: Landfill Remediation

MP&A recently implemented a large remediation project to remove contaminated soil from a former industrial landfill site.  The work required the use of multiple contractors and waste disposal facilities.  MP&A worked closely with the client to evaluate the options for contractor and disposal facilities and to establish the most cost effective completion of the remediation.

Construction

Case Study: Excavation and Backfill Construction

At a coastal Louisiana site, approximately 20 acres of combined wetland/upland area were impacted with salts and hydrocarbons from historical oil and gas operations. MP&A developed an approach to remove the soils with the highest concentrations (approximately 10,000 cubic yards) and transport the soils to an offsite commercial landfill for disposal.  MP&A designed a soil treatment program to reduce concentrations of remaining constituents and to return the site to agricultural use. 

Elements of the excavation program included:

  • Designing a safety program to ensure that excavation could be performed without incident;
  • Performing detailed sampling to demonstrate that affected soils were appropriately delineated for removal;
  • Designing a traffic flow protocol to protect onsite personnel and the neighboring public;
  • Specifying protocols for truck loading to provide control measures to reduce potential for offsite impacts (i.e., truck liners, manifest system, and inspection of trucks);
  • Specifying appropriate soils for backfill (high clay content soils at depth and organic rich soil to support vegetation at the surface);
  • Leveling/grading property and planting suitable ground cover.

Litigation Support

Case Study: Expert Opinion and Report

In a coastal Louisiana setting, the plaintiffs’ consultant claimed damages to canal sediments and groundwater from oil and gas exploration activities.  Their proposed remedial approach would have resulted in the destruction of approximately 50 acres of sensitive marsh environment through the installation of a containment system and a groundwater pump and treat program that would have taken approximately 30 years to accomplish, at a total cost of over $150 million. MP&A’s approach was to remove unused oil field equipment (tanks, flow lines, etc.) in an environmentally-conscious manner, remediate two former oil field pits, and assess groundwater for monitored natural attenuation with a contingent remedy to treat isolated groundwater concerns at total remediation cost of approximately $4 million. This remediation approach addressed environmental concerns in a timely and cost-effective manner with minimal impact to the thriving marsh ecosystem.

Case Study: South Louisiana Blue Crab Population Field Study

MP&A performed a large field study of a native crab population in Vermilion Parish, Louisiana. This study included the trapping, counting, weighing, measuring, and shipping for tissue and carapace analysis of more than 300 crabs in a fresh/intermediate wetlands environment. Crabs were collected from 23 sampling locations in canals, bayous and lake settings.  We compared statistics on size, weight and abundance from this study to populations throughout the Gulf of Mexico region to determine the health of the measured ecosystem.

Also collected and assessed for this study were shad fish and counts of wetland birds and native vegetation. These data were used to complete an EPA-compliant wetlands rapid assessment measuring the function and services of the ecosystem.

Wetlands & Coastal Ecology

Case Study: Coastal Use Permitting

Recently, we obtained authorization from the US Army Corps of Engineers, Louisiana Department of Natural Resources and a local parish government to conduct an environmental assessment in the coastal zone in close proximity to a flood protection levee.

Facility Closure

Case Study: Facility Closure

Our team assisted a customer in closing a fabrication facility that had been in operation for more than 50 years. The work included:

  • Phase I Assessment which identified all areas impacted by historical operations
  • Sampling and remediating affected areas
  • Removing hazardous waste and asbestos
  • Cleaning sumps
  • Emptying and backfilling septic systems
  • Demolishing buildings
  • Disposing trash and debris
  • Cleaning the buildings and locking the gates

Our work reduced the customer’s future liability associated with long term use of the property and returned the property to the owner in good condition. The owner can now lease the property for industrial use to a new tenant.

Environmental Compliance & Reporting

Case Study: Environmental Compliance and Reporting

MP&A is the principal environmental consultant for a large pipeline company with multiple sites.  We have assisted our client in working with the regulators on pipeline releases including initial reporting and response, recovery, remedy selection and site closure.  In addition, we provide routine monitoring services for groundwater to document progress of recovery efforts and effectiveness of remediation systems.  With our strong capabilities in litigation support, we are able to conduct this work on litigation and non-litigation projects.

Air Monitoring & Air Quality

Case Example: Air Quality Monitoring

MP&A successfully implemented an air monitoring program at a difficult remediation site.  The activities involved excavation of contaminated soil in a temporary enclosure with fence line monitoring for a nearby residential area.  The program was designed to protect area residents, enhance worker safety and document air quality during remedial activities.

Case Study: Air Quality Analysis

MP&A performed an analysis of air quality and a human health risk assessment of sulfur compounds in outdoor air.  In this case, an accidental release of hydrogen sulfide and sulfur dioxide gases from a refinery traveled into a neighborhood adjacent to the refinery.  Some nearby residents called LDEQ and the refinery and complained of an odor.  The refinery sent air sampling contractors into the neighborhood within 20 minutes of the release.  The air was sampled in the path of the release over the next five hours and then again the next day. 

Our risk assessment team used the data from the neighborhood sampling event and the information from the nearby LDEQ monitoring station to perform a human health risk assessment.  We used the highest measured air concentrations for both H2S and SO2, as well as the longest possible exposure durations measured in the field.  Using these maximum values we calculated the risk of health effects based on an acute exposure to H2S and to SO2.  To perform the assessment, we did an extensive review of the scientific literature to understand the concentrations and durations at which acute effects occur.  Our opinion on the case was presented in federal court and the judge dismissed claims of health effects presented by opposing counsel.