LSPA Continuing Education Online Course  

LNAPL Natural Source Zone Depletion (NSZD) 

Registration: Registration must take place during business hours (8 am to 6 pm Mon. - Fri.). Within 24 hours of registration, the LSPA will provide your registration information via email. 
Availability: Once you have your login information, the course may be accessed at any time for 30 days through a web browser. At the end of 30 days, your access is terminated. No extensions will be offered. 
Technology: The course may be accessed using a computer, tablet or mobile device. All you need is a web browser and access to the Internet. Preferred browsers include: Google Chrome, Safari, Edge and Firefox. Please note: Internet Explorer 11 (IE11) is not a supported browser. 
Course Instructor: Steven Gaito, NAPL Technical Specialist, AECOM (Instructor Biography)
Pricing: Member $75 | Non-Member $225

This course has been approved for 1.0 Technical Credit (#1691A). This course was first presented by the LSPA as a live webinar (#1691) on April 15, 2020. If you received LSP Technical credit then, you will be unable to also receive LSP credit for taking this on-demand course.

Course Description:

NSZD is the combination of natural processes that decrease the mass of non-aqueous phase liquid (NAPL) in the subsurface over time. The mechanisms responsible for NAPL depletion include volatilization, dissolution, and biodegradation. The observation of NSZD rates on the order of hundreds to thousands of gallons per acre, per year (Garg et al. 2017) has elevated the role of NSZD in LNAPL conceptual site model (LCSM) development and site management decision making. NSZD measurements are more frequently utilized to achieve a variety of objectives. For the LSP, NSZD can be an additional line of evidence to support a permanent solution. The increased reliance on NSZD data reflects the importance for accurate measurements to support informed management decisions.

This course will include:

  • Introduction to NSZD 
  • Scientific Basis for NSZD
  • NSZD Implementation, specifically data acquisition and analytical requirements
  • Data Interpretation
  • Regulatory Implications


Please click here to review the LSPA Course Cancellation Policy.