Founded in 1997, XDD, LLC is an environmental consulting and engineering firm that focuses on the evaluation, design and implementation of remedial technologies. Since our founding, XDD has earned a national reputation for its:

  • remediation expertise and for the ability to develop site exit strategies
  • evaluate remedial alternatives
  • negotiate regulatory options
  • conduct laboratory and field pilot testing, and
  • design and implement a variety of full-scale soil and groundwater remediation technologies.

XDD utilizes each of these steps to better meet our client’s goals of achieving regulatory closure, reducing risk, and minimizing long-term costs.

“Our command of the latest technologies and national regulatory knowledge let us provide alternatives that will get the job done right. With some clean-ups taking several years, we’re sensitive to the need for timely and cost-effective solutions, which is something we deliver every step of the way, from investigation through implementation and monitoring.”


Michael C. Marley, President

As a firm that employs highly-skilled remediation experts, XDD qualifies as a small business enterprise under the NAICS codes 541620 (Environmental Consulting Services) and 562910 (Remediation Services). XDD can provide turn‐key solutions or support your engineering team, and we have a very successful track record of teaming with consulting firms on numerous private and government projects.

Email XDD at for case studies associated with our in situ remedial technology experience.


  • Conducted in-situ remediation activities at 100’s of sites and have successfully injected >2 million pounds oxidants
  • First application of air sparging in US in 1989
  • Authored American Petroleum Institute’s Air Sparging Guidance Document (1996)
  • First application of pure oxygen biosparging in 1994/1995 (EPA Region 1 Superfund Site)
  • First in US to apply stabilized hydrogen peroxide
  • First in US to apply activated persulfate and combined permanganate and persulfate (DUOX)
  • Authored USEPA Innovative Technology Evaluation Report Xpert Design and Diagnostics’ (XDD) In Situ Cehmical Oxidation Process Using Potassium Permanganate
  • Co‐authored four chapters in the SERDP/ESTCP manual, In Situ Chemical Oxidation for Groundwater Remediation (Siegrist, et al.)
  • Contributed to ITRC Technical and Regulatory Guidance for In Situ Chemical Oxidation of Contaminated Soil and Groundwater (2005)
  • Conducted EPRI‐sponsored study for the treatment of MGP residuals with In Situ Chemical Oxidation for the utility industry
  • Co‐Principal Investigator in DOD SERDP-funded research on potential for metals mobilization and prevention during ISCO (ER‐2132)
  • Contributor, Soil Vapor Extraction using Radio Frequency Heating (Lowe, et al.)
  • Developed application of radio frequency heating (RFH) to accelerate SVE and biodegration processes
  • Assisted EPA with developing soil gas monitoring protocols for Assessment of Vapor Intrusion in Homes Near the Raymark Superfund Site Using Basement and Sub-Slab Air Samples (2006)
  • Successful treatment of emerging contaminants such as PFOS, PFOA, and 1,4-dioxane for our industrial clients
  • Contributed to in situ chemical oxidation component of Chlorinated Solvent Source Zone Remediation (2014)