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NEW - Tygon Connectors!The Vapor Pin® Kit is designed to make your use of our products a success each time. However, one item was previously not included - the connector to match the barb fitting to the sample train. From this point forward, our kits will include Tygon connectors to bridge the distance between your sampling train and the Vapor Pin® Sampling Device. You may also purchase a bag of Tygon connectors separately or in 5 foot lengths.https://www.vaporpin.com/product/tygon-connectors-10-pieces/ ... See MoreSee Less
Vapor Pin is at Ferrara.
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I'm thrilled to share with you the program of Remtech Europe 2021. This important environmental conference is made of 23 sessions fully ONLINE. Any session is completely FREE.To follow any session you have to register in our website https://remtech.meeters.space with a valid email. To reserve your seat, receive the presentations in pdf and receive your Certificate of Attendance of the session you will attend, you have to register in the Google form of each session. In each form you would find also the detailed program and beginning and end in different time zones. Reserve your seat today!SESSION 1 (Organized by JRC-European Commission) From policy talking to industry actions: Zero Pollution for Soil Mon 20 SEPTEMBER 09:00 – 13.00 CEST https://forms.gle/RhvqacpBJKrXvveq6SESSION 2 (Organized by US Army Corps of Engineers) TRAINING COURSE - PFAS: characterization, environmental impact, remediation strategies Mon 20 SEPTEMBER 14.30 – 19.00 CEST https://forms.gle/pSJzwMWt7G1mERUKASESSION 3 Sustainable management of contaminated sites Mon 20 SEPTEMBER 14.30 – 16.30 CEST https://forms.gle/GzgcfXHWEzTySktVASESSION 4 Waste tailings and acid mine drainage: challenges for Mining Sites Mon 20 SEPTEMBER 17.00 – 19.00 CEST https://forms.gle/RqQLnZqXeoJd5dKK8SESSION 5 Bioremediation and phytoremediation in agricultural, industrial, and military sites Tue 21 SEPTEMBER 09.00 – 11.00 CEST https://forms.gle/sScosaSUwsSh5AH79SESSION 6 Oil and hydrocarbons impacted sites Tue 21 SEPTEMBER 11.30 – 13.30 CEST https://forms.gle/VFx1Re2txyaxF2z78SESSION 7 HRSC, High Resolution Site Characterization Tue 21 SEPTEMBER 11.30 – 13.30 CEST https://forms.gle/okDrkFA8YrsAUhcRASESSION 8 (Organized by ASTM) TRAINING COURSE - ASTM STANDARDS: PFAS, Sediment and Climate Resilience Tue 21 SEPTEMBER 14.30 – 19.00 CEST https://forms.gle/pnz5H6edwFi6p1QA9SESSION 9 Innovative, digital and smart characterization techniques tools Tue 21 SEPTEMBER 14.30 – 16.30 CEST https://forms.gle/5MvheZmiPq5aQphW8SESSION 10 Circular Economy: how to apply it in the context of the next Generation EU Tue 21 SEPTEMBER 17.00 – 19.00 CEST https://forms.gle/tHBuZXpuraKiHYwi8SESSION 11 Soil remediation: can we deal in a sustainable way? Wed 22 SEPTEMBER 09.00 – 11.00 CEST https://forms.gle/Zh8gKvK1bn8BxcJk9SESSION 12 DNAPL and chlorinated compounds: optimize the process to achieve the target Wed 22 SEPTEMBER 11.30 – 13.30 CEST https://forms.gle/M8zcit6jQiNaBa446SESSION 13 (Organized by SERDP-ESTCP) TRAINING COURSE - Current Approaches for Vapor Intrusion Site Investigation and Mitigation Wed 22 SEPTEMBER 14.30 – 19.00 CEST https://forms.gle/q4BigJhPv891kG4U8SESSION 14 (Organized by Ramboll) TRAINING COURSE - Sustainability assessment as a tool for a more sustainable and resilient remediation of soils, groundwater and sediments Wed 22 SEPTEMBER 14.30 – 16.30 CEST https://forms.gle/LFBFwAaWqdnvPQUb8SESSION 15 PFAS, remediating the forever chemical Wed 22 SEPTEMBER 17.00 – 19.00 CEST https://forms.gle/H3yXyRzBshvKifBM9SESSION 16 Microplastics and sediments: two main threats for ports and coastal areas Thu 23 SEPTEMBER 09.00 – 11.00 CEST https://forms.gle/GQCAfXJ142r23r2B9SESSION 17 Sustainathon Thu 23 SEPTEMBER 14.00 – Fri 24 SEPTEMBER 14:00 CEST https://forms.gle/zCQBwt3eG1xBFGSM7SESSION 18 Aeriforms and vapor intrusion: measures and models Thu 23 SEPTEMBER 11.30 – 13.30 CEST https://forms.gle/m1KikTrbNncick936SESSION 19 Groundwater remediation in difficult conditions Thu 23 SEPTEMBER 11.30 – 13.30 CEST https://forms.gle/d9neHnF2sP9mN8hu6SESSION 20 (Organized by AESAS) TRAINING COURSE - State of the art of contaminated sites in Brazil Thu 23 SEPTEMBER 14.30 – 19.00 CEST https://forms.gle/Yy5hBLnzX2qngWcS8SESSION 21 River environment: managing impacts from different sources Fri 24 SEPTEMBER 09.00 – 11.00 CEST https://forms.gle/Ydgj3UFN13TTg3Yk8SESSION 22 Wastewater and sewer sludge, handling the last link in the chain Fri 24 SEPTEMBER 11:30 – 13.30 CEST https://forms.gle/L6Tsi5zPVfUpWQhEASESSION 23 TRAINING COURSE: Wastewater control and seawater quality: it is possible to do it acting differently? Fri 25 SEPTEMBER 14.30 – 19.00 CEST https://forms.gle/mvTELbnKXZr4S6cs5Feel free to share to your colleagues or to any contacts that you think he/she may be interested. REMEMBER THAT THE CONFERENCE IS FREE, NO FEES. JOIN US !See you online!Laurie A. ChilcoteRemtech Europe Ambassador ... See MoreSee Less
Vapor Pin is at RemTech Expo.
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Decontamination and Decommissioning of Warehouses - Gela Industrial Site. - Author: Mariangela Venco (ENI Rewind) RemTech Expo ... See MoreSee Less
We are excited to announce our Brazil Patent BR 11 2018 004186-6 has been granted!#remediation #vaporintrusion #contaminatedsites #vaporpin #vi #coxcolvin #patent #Brazil ... See MoreSee Less
Don't miss out, join us next week at one or all of the following webinars to see and be seen!Tuesday - May 19th with Brownfield Summit, Craig Cox will be presenting at 10:35 EST - Evaluating and Remediating a Complex Contaminated Groundwater Plumehttps://www.brownfieldsummit.com/programmeWednesday - May 20th with MSECA - Craig Cox will be presenting on Sanitary Sewers as the Expected Preferential Pathway in Vapor Intrusion Evaluations.http://mseca.org/2020-05_-_Seminar.phpThursday - May 20th with Alpha Labs, Join Craig Cox and Laurie Chilcote as they do a live sub-slab demo Vapor Intrusion: Sampling with Confidence for Mid-Atlantic Stateshttps://register.gotowebinar.com/register/8677107578848466445 ... See MoreSee Less
We are excited to participate in the virtual seminar Vapor Intrusion: Sampling with Confidence for the Mid-Atlantic region, with Mark Mank of the Maryland Department of the Environment, Todd Creamer of Geosyntec Consultants, Christina Lewis at Langan Engineering & Environmental Services, Craig Cox at Cox-Colvin and Associates, Inc. and our own William Elcoate and Andy Rezendes. This event is free. NJ LSRP CEC Application for credits is pending. Registration is open: https://lnkd.in/djzaP9B ... See MoreSee Less
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Main Content

August 2019 Vapor Pin Article


Vapor Intrusion Fundamentals 47 – Sanitary Sewers, the Preferential Pathway, Part 1

By: Craig A. Cox, CPG

In general, Vapor Intrusion (VI) assessments can be thought of as a three-legged stool, with each leg representing a contributing source that must be understood; including: contributions associated with soil gas, contributions associated with indoor sources, and contributions associated with preferential pathways.

Until recently, most assessment efforts (and modeling) have focused on the first two legs – understanding the contributions from soil gas and the contributions from indoor air. The third leg, contribution from preferential pathways, is generally given lip service but rarely evaluated in a rigorous manner.

In the past, the preferential pathway has been considered the trenching and permeable backfill associated with underground utilities.  However, when you consider that a sanitary sewer is essentially an air-filled conduit providing a direct vapor pathway into every inhabited building, more often than not, the sanitary sewer will be the preferential pathway of concern.

Not understanding this third leg of VI assessment stool can lead to a misdiagnosis of the issues and implementation of ineffective mitigation efforts.  This is a game changer when you consider that: sanitary sewers have been an integral part of the industrial waste elimination systems for years through permitted discharges to publicly-owned treatment works (POTWs), the “drain” has been an easily accessible disposal route for those that have used solvents and may not have obtained discharge permits, sanitary sewers used by industry are, in many instances, the same ones used by homes in the same neighborhood, sanitary sewers are typically plagued by failures or penetrations from tree roots, sanitary sewers may extend below the water table (before entering a lift station), and sanitary sewers contain a great deal of air-filled space that is essentially connected to every home and business along its route.

Plumbing traps (P-Traps) and seals (e.g., wax toilet rings) in our plumbing systems typically prevent the intrusion of sewer gas into our homes and businesses, and vent pipes on the soil stack allow these vapors to vent to the atmosphere.  However, P-Traps can dry out, wax rings can fail, and stacks within the home or business can develop cracks or other failures allowing vapors within the sewer to enter the indoor air space.

So how does this result in a misdiagnosis of the issue?  Let’s say you collect sub-slab soil gas and concurrent indoor air samples above VOC contaminated groundwater and find that similar compounds are detected in both.  This could look like a line of evidence indicative of VI. The tendency may be to mitigate with a sub-slab depressurization (SSD) system.  However, if the plume intersects the sanitary sewer line, or the bed of the sanitary sewer line is impacted by a history of solvent disposal, then the vapors may be coming into the indoor space through the sewer connection which will not be mitigated by SSD.  Instead, ensuring that the P-Traps are filled, replacing defective toilet seals and repairing sewer line breaks could mitigate the issue. In the end, it is important keep in mind all of the potential migration pathways when you develop your conceptual site model and take steps to evaluate each pathway before you move to mitigation.  In the next installment, we will review approaches used to evaluate sewer connections and deciphering the associated analytical data.


Craig Cox is a principal and co-founder of Cox-Colvin & Associates, Inc., and holds degrees in geology and mineralogy from the Ohio State University and hydrogeology from the Colorado School of Mines. Mr. Cox has over 30 years of experience managing large environmental project implemented under CERCLA and state voluntary action programs. Mr. Cox is the inventor of the Vapor Pin® and has developed a variety of software products including Data Inspector, an internet-enabled environmental database application. Mr. Cox is a Certified Professional Geologist (CPG) with AIPG and is a Certified Professional (CP) under Ohio EPA’s Voluntary Action Program.