Lawrence McTiernan, PG, LSP

Principal Hydrogeologist


Contact Information

Phone: (781) 569-4000


Location: Burlington, MA


Site Investigation and Remediation

Contaminant Fate and Transport

Regulatory Negotiations

Litigation Support

Data Quality Evaluation

Sedimentary Geology


MS, Marine Environmental Sciences - State University of New York at Stony Brook

BA, Geology - Lafayette College

Lawrence McTiernan, PG, LSP

Principal Hydrogeologist

Mr. McTiernan is a Professional Geologist and Massachusetts Licensed Site Professional (LSP) with over thirty years of experience in site investigation and remediation. He is currently a Principal Hydrogeologist with Roux, with whom he has spent his entire professional career. Mr. McTiernan joined Roux in 1989 after receiving an MS degree in Marine Environmental Sciences from the Marine Sciences Research Center at the State University of New York at Stony Brook. He also holds a BA degree in Geology from Lafayette College.


Mr. McTiernan has conducted, managed, or overseen site investigation and/or remediation projects at many high-profile sites in Massachusetts and around the country, including a number of Superfund sites in New York and New England. These sites have been contaminated with a variety of constituents, mainly chlorinated solvents, petroleum compounds, and metals. His work has involved extensive negotiations and other interface with regulatory agencies, at both the federal and state level. He is currently representing one of his clients on the technical committee for a multi-PRP Superfund site in New England. Mr. McTiernan also provides high-level technical and managerial support for environmental litigation projects.

representative projects
  • Consultant for RD/RA performing party for Operable Unit 2 of the Peterson/Puritan Superfund Site in Cumberland, Rhode Island, including the JM Mills Landfill. Currently representing client as a member of Technical Committee for RD/RA performing parties, providing review and critique of remedial design submittals and assisting in regulatory negotiations. Other work has included assisting in development of allocation agreements, supporting the client during FS, critiquing the EPA’s Proposed Plan on behalf of the client, preparing a white paper proposing a new remedial alternative not included in final the FS (evapotranspiration [ET] cap), and presenting a new capping alternative at an EPA public meeting.
  • Principal-in-Charge for long-term surface water monitoring project at the Industri-Plex Superfund Site in Woburn, Massachusetts. Project initially (during RD/RA phases) involved deployment and maintenance of automated surface water monitoring and sampling equipment at ten locations along a 6-mile reach of river at and downstream of the Site, hydraulic characterization of stations, continuous monitoring of stream flow and water quality, and periodic sampling under both baseflow and storm conditions. Currently (post-remedy) maintaining equipment at two full-time monitoring stations and performing monitoring during storm conditions at eight stations.
  • Principal-in-Charge for supplemental remedial investigation activities for Operable Unit 2 at the Industri-Plex Superfund Site. Work performed following successful demonstration by Roux of the technical infeasibility of ROD interim remedy (pump-and-treat) and the intrinsic bioremediation potential of pond and wetland sediments. Performed supplemental source area investigations, vertical profiling of groundwater contamination, sediment remobilization/transport study, and delineation/sampling of buried lakebed. Also prepared work plans and supporting Project Operations Plans (FSP, QAPP, HASP).
  • Project Manager and later Principal-in-Charge for implementation of groundwater remedy at the Fulton Terminals Superfund Site in Fulton, New York. Successfully negotiated and implemented an Expedited Pumping Program (EPP) as an alternative to ROD-specified remedy for chlorinated VOCs in groundwater. EPP involved short-term (12 weeks) pump-and-treat using a mobile treatment system, periodic sampling of groundwater, and modeling of post-pumping natural attenuation of residual groundwater impacts. Project also included a geophysical survey to determine extent and decay rate of remnants of freeze wall used during soil remedy (conducted by others), which was delaying complete natural attenuation of site groundwater. Successfully argued, based on success of EPP and natural attenuation modeling, that additional active remediation of site groundwater was not necessary, and prepared Construction Completion Report. Performed over ten years of long-term groundwater monitoring supporting delisting of site from the NPL in 2018.
  • LSP-of-Record and Principal-in-Charge for MCP Response Actions at a Tier 1A former dry cleaner site in northeastern Massachusetts. Site soil and groundwater contain PCE and degradation products, which have also been detected in indoor air of the existing site building. Project has included review of Downgradient Property Status Submittal prepared for adjacent property, completion of MCP Phase I and Phase II investigations (including Method 3 risk characterization), and Immediate Response Action to evaluate source, persistence, and effects of CVOC discharge to surface water from a local municipal stormwater sewer. Also assisted client in negotiations with adjacent property owners, including review/critique of demands for reimbursement of response action costs under M.G.L. c.21E.
  • LSP-of-Record for MCP Response Actions at a former asphalt-shingle manufacturing facility in central Massachusetts. Site soil and groundwater are impacted with petroleum hydrocarbons, and deeper site groundwater is impacted with chlorinated volatile organic compounds (CVOCs). Project has included excavation and management of 4,700 cubic yards of buried asphalt and asphalt-impacted soil as a Release Abatement Measure, completion of a supplemental Phase II investigation reevaluating extent of petroleum impacts and demonstrating off-site source for CVOCs in deeper groundwater, and consulting for client during facility demolition. Currently performing Phase III evaluation of remedial action alternatives.
  • TRW Inc. v. Lloyd’s of London et al. (1999) Philadelphia County Court of Common Pleas, Expert Report, Deposition, Settled Prior to Trial.

  • Liberty Mutual Insurance Company v. The Black & Decker Corporation, et al. (1997-2005); U.S. District Court, District of Massachusetts; Case 96-10804-DPW.1.