Simplicity Drives Remediation Success

Less Is More: Simplicity Drives Remediation Success

In environmental remediation, complexity often becomes its own agenda. When a solution is intricate enough, its very existence seems to validate the designer’s expertise.

But success comes from simplicity: solid characterization, a conceptual site model centered on contaminant mass and location, and a remedy focused on the client’s real needs. No single remedy fits every site, but keeping it simple is an excellent instinct.

Trap and Treat: A Proven Approach

RPI has follows one approach: trap contamination in activated carbon to eliminate risk pathways, then destroy the captured contaminants through abiotic and/or biotic means.

Why It Matters

In an industry where technical complexity abounds, sometimes the most innovative solution is the one you can explain in a single sentence. Trap and Treat products have delivered faster timelines, lower costs, and reliable results across hundreds of sites for over 23 years.

                                Edward Winner

                                Vice President, RPI

Webinar November 11th, 12:00 pm EST

Enhancing Dehalococcoides Populations Without Augmentation: Insights from Chlorinated Solvent-Contaminated Sites Treated with CAT 100

Background/Objectives

Dehalococcoides (Dhc) are among the most well-known bacteria introduced to sites via augmentation cultures. We will examine multiple chlorinated solvent-contaminated sites treated with CAT 100 without Dhc augmentation and demonstrate the emergence or increase in abundance of Dhc population.

Approach/Activities

The investigation focuses on chlorinated contamination sites that have been treated with CAT 100. The microbial populations were analyzed using Next-Generation Sequencing (NGS), complemented by soil and groundwater data.

Results/Lessons Learned

Results demonstrate that Dhc populations can increase from levels below NGS detection limits to comprising over 90% of the microbial community. The pattern is consistent across multiple sites. These findings underscore the potential to enhance Dhc abundance without external augmentation using CAT 100.

The image is of two disc shaped Dehalococcoides strain CBDB1. Adrian, L., 2009. ERC-group microflex: microbiology of Dehalococcoides-like Chloroflexi. Reviews in Environmental Science and Bio/Technology, 8(3), pp.225-229.

Two Minute Case Study

Are Dehalococcoidia Ubiquitous Environmental Constituents?

Evidence from culture-independent surveys suggests that the class Dehalococcoidia (Dhc) is widespread and an intrinsic member of natural ecosystems rather than a rare specialist confined to contaminated sites. They have been detected in over 88% of uncontaminated soils and in 67 of 68 lake sediment samples across marine, freshwater, and terrestrial settings. Their consistent presence in media unaffected by anthropogenic organohalogens indicates that Dhc are native environmental denizens with broad ecological distribution.

Natural halogen cycling likely drove the evolutionary emergence of Dhc. More than 5,000 naturally occurring organohalogens—predominantly organochlorines—exist in soils and sediments, providing long-standing substrates for reductive dehalogenation. The ability of Dhc to respire these compounds, therefore, reflects adaptation to pre-industrial biochemical niches rather than dependence on anthropogenic pollution.

Finally, Dhc plays a keystone role in anaerobic consortia by scavenging hydrogen, which enables syntrophic partners to sustain otherwise unfavorable metabolisms. This function anchors them within the energy economy of anoxic ecosystems. Combined with their prevalence in pristine systems, this metabolic centrality strongly supports the view that Dhc are ubiquitous environmental constituents poised to respond whenever suitable electron acceptors and partners are present.

Yang, Y., Sanford, R., Yan, J., Chen, G., Cápiro, N.L., Li, X. and Löffler, F.E., 2020. Roles of organohalide-respiring Dehalococcoidia in carbon cycling. Msystems, 5(3), pp.10-1128.

The above Dhc counts came from a heavy oil site without chlorinated solvent contamination. Both background wells and impacted wells had low Dhc counts. Next generation sequencing from multiple unimpacted and background samples have shown low concentrations of Dhc.