Sam is learning about Radon today. ... See MoreSee Less
Resilience and Motivation. Learning can build resilience, because-by definition-learning requires you to realize you don't already know it all and encourages you to try something new and fill in gaps of information.There are still a lot of people who still do not know about Vapor Intrusion. And in the spirit of educating, learning, and growing. For those in and out of the field. Click on the video below. Feel free to share! #growthmindset #vaporintrusion #vaporpin ... See MoreSee Less
One of our own, Kyle Chilcote, has been going through some Physical Therapy for some ATFL (Anterior Talo-Fibular Ligament) Damage recently. He's taken advantage of his unfortunate situation by learning more about SEO (Search Engine Optimization)! Kyle says, "It has really helped me in understanding the frustrations that all SEO specialists have. Especially when it comes to all of the things that should be thought of prior to a web page coming into existence." He has suggested brushing up on SEO terms is very helpful. Especially, "For anyone else who also has the urge to make sure that an employee or vendor is set up for success prior to a project." If anyone is interested in what he was using to learn. He was following along with the Simplilearn free youtube videos! The playlist link is below.#learning #searchengineoptimization #success #vaporintrusion #vaporpin ... See MoreSee Less
Join us February 13th for a band on workshop at Ecosearch srl. See you soon🔹 Vi avevamo promesso delle novità, vi avevamo promesso che quest’anno tornavamo ad organizzare Workshop nella nostra azienda e così abbiamo fatto.🆕 Il 13 febbraio si terrà nella nostra sede un Workshop VaporPin. Nel nostro sito potete scaricare il programma e il modulo di adesione, qui di seguito il link ⬇️: partecipazione è gratuita, dovete solo compilare il modulo di adesione e mettere su Google Maps “EcoSearch” per raggiungerci.Vi aspettiamo numerosi, non vediamo l’ora di accogliervi nella nostra azienda!!Vapor Pin#VaporIntrusion #Remediation #SitiContaminati ... See MoreSee Less
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. ... See MoreSee Less
Vapor Pin is at Ferrara.
Vapor Pin
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 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 2 (Organized by US Army Corps of Engineers) TRAINING COURSE - PFAS: characterization, environmental impact, remediation strategies Mon 20 SEPTEMBER 14.30 – 19.00 CEST 3 Sustainable management of contaminated sites Mon 20 SEPTEMBER 14.30 – 16.30 CEST 4 Waste tailings and acid mine drainage: challenges for Mining Sites Mon 20 SEPTEMBER 17.00 – 19.00 CEST 5 Bioremediation and phytoremediation in agricultural, industrial, and military sites Tue 21 SEPTEMBER 09.00 – 11.00 CEST 6 Oil and hydrocarbons impacted sites Tue 21 SEPTEMBER 11.30 – 13.30 CEST 7 HRSC, High Resolution Site Characterization Tue 21 SEPTEMBER 11.30 – 13.30 CEST 8 (Organized by ASTM) TRAINING COURSE - ASTM STANDARDS: PFAS, Sediment and Climate Resilience Tue 21 SEPTEMBER 14.30 – 19.00 CEST 9 Innovative, digital and smart characterization techniques tools Tue 21 SEPTEMBER 14.30 – 16.30 CEST 10 Circular Economy: how to apply it in the context of the next Generation EU Tue 21 SEPTEMBER 17.00 – 19.00 CEST 11 Soil remediation: can we deal in a sustainable way? Wed 22 SEPTEMBER 09.00 – 11.00 CEST 12 DNAPL and chlorinated compounds: optimize the process to achieve the target Wed 22 SEPTEMBER 11.30 – 13.30 CEST 13 (Organized by SERDP-ESTCP) TRAINING COURSE - Current Approaches for Vapor Intrusion Site Investigation and Mitigation Wed 22 SEPTEMBER 14.30 – 19.00 CEST 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 15 PFAS, remediating the forever chemical Wed 22 SEPTEMBER 17.00 – 19.00 CEST 16 Microplastics and sediments: two main threats for ports and coastal areas Thu 23 SEPTEMBER 09.00 – 11.00 CEST 17 Sustainathon Thu 23 SEPTEMBER 14.00 – Fri 24 SEPTEMBER 14:00 CEST 18 Aeriforms and vapor intrusion: measures and models Thu 23 SEPTEMBER 11.30 – 13.30 CEST 19 Groundwater remediation in difficult conditions Thu 23 SEPTEMBER 11.30 – 13.30 CEST 20 (Organized by AESAS) TRAINING COURSE - State of the art of contaminated sites in Brazil Thu 23 SEPTEMBER 14.30 – 19.00 CEST 21 River environment: managing impacts from different sources Fri 24 SEPTEMBER 09.00 – 11.00 CEST 22 Wastewater and sewer sludge, handling the last link in the chain Fri 24 SEPTEMBER 11:30 – 13.30 CEST 23 TRAINING COURSE: Wastewater control and seawater quality: it is possible to do it acting differently? Fri 25 SEPTEMBER 14.30 – 19.00 CEST 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.
Vapor Pin
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

Main Content

Vapor Intrusion Fundamentals 48 – Sanitary Sewers, the Preferential Pathway, Part 2


Sanitary Sewers, the Preferential Pathway, Part 2

By: Craig A. Cox, CPG

Published in the June 2020 VAPOR PIN® Newsletter

As discussed in the January 2020 installment of Vapor Intrusion Fundamentals (Number 47), sanitary sewer lines are becoming recognized as an important, yet often overlooked, pathway for vapor intrusion (VI).  In this installment, we will review approaches used to evaluate sewer connections and deciphering the associated analytical data collected during VI assessments.

As a reminder, VI assessments can be thought of as a three-legged stool, with each leg representing a contributing source that must be understood:

1 – contributions associated with soil gas,

2 – contributions associated with indoor sources, and

3 – contributions associated with preferential pathways.

Not understanding this third leg of VI assessment stool can lead to a misdiagnosis of the issues and implementation of ineffective mitigation efforts.

The first step in the assessment of the vapor contribution associated with sewer gas is to develop a sound conceptual site model (CSM) that recognizes and anticipates this preferential pathway.  Trunk sewer lines, especially those is areas served by industries that used solvents, can transport volatile organic compounds over relatively long distances downgradient and contaminate environmental media (soil and groundwater) through degraded sections and defects in the lines. These areas should be thought of as secondary point or line sources.  Assessing the locations of these secondary sources can be done through detailed inspections of the lines using cameras. Many communities have done these studies in preparation for sewer improvement projects.

Understanding the potential effect of degraded sewers on your study area is an important aspect of the CSM and the overall evaluation of a neighboring buildings and/or houses, however, most investigations begin with an assessment of a single building.  You can get a sense of the potential contribution of sewer gas on your building through the collection of sewer gas samples from nearby manholes and cleanouts.  In addition to your chemicals of concern (e.g., chlorinated VOCs), you should also analyze for other chlorinated and brominated compounds (e.g., chloroform, bromoform, and bromodichloromethane), as these compounds are typically found in sanitary sewer gas as a result of the breakdown of household and industrial cleansers.

As you begin your indoor air sampling campaign, review your sewer gas data closely.  If your chemicals of concern are found in sewer gas, then you should inspect the lavatories and areas containing floor drains as possible sampling locations.  If you collect samples from lavatories, conduct the sampling with the door shut and the fan running to induce air flow through plumbing leaks. After you receive the analytical results, review the dataset for the indicators of sewer gas (chloroform, bromoform, and bromodichloromethane) as well as the ratios of your chemicals of concern and compare them to your sub-slab and sewer gas data.  These comparisons will help you determine if the sanitary sewer represents a complete pathway for VI. In a recent study completed by Cox-Colvin, sewer gas was determined to be the primary pathway of VI at more than half of the buildings evaluated.

Accounting for the sewer gas VI pathway in your CSM provides you with additional insight into potential sources as well as appropriate means of mitigation. Sub-slab depressurization systems (SSDs) are very effective at interrupting the VI pathway associated with a sub-slab source; however, SSDs are typically not effective at mitigating the sewer gas source. If the VI pathway is dominated by the sanitary sewer line source, simple plumbing repairs could be enough to mitigate the VI issues.

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.