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    <title>Research in Progress (RIP)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Research in Progress (RIP)</title>
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      <link>https://rip.trb.org/</link>
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    <item>
      <title>Leveraging Existing Vegetated Roadside Areas for Efficient Stormwater Management</title>
      <link>https://rip.trb.org/View/2726138</link>
      <description><![CDATA[Stormwater runoff from transportation infrastructure presents a persistent challenge for Oregon’s transportation system due to the requirement to treat highway stormwater runoff and protect downstream water quality. Current regulatory requirements compel project teams to demonstrate adequate stormwater treatment and infiltration performance during planning and design. However, limited understanding of how hydrologic data and roadside soil properties influence geochemical treatment capacity often prevents reliable evaluation of whether the natural roadside environment itself can meet objectives, providing an unrealized opportunity for potential savings on unnecessary facility installation and maintenance costs.
OBJECTIVES: The overall objective of this project is to develop and validate an integrated hydrologic-geochemical decision-support tool that enables early-stage screening of existing roadside stormwater infiltration potential and treatment performance. The tool will provide Oregon Department of Transportation (ODOT) with simulation capabilities to predict and quantify surface runoff routing, infiltration capacity, and subsurface geochemical dynamics. The coupled hydrologic-geochemical framework will support quantitative evaluation of whether already existing roadside environments can meet stormwater performance metrics and identify locations where built treatment facilities are actually necessary. 
The project will provide ODOT with quantitative decision-support framework for early-stage screening of roadside stormwater infiltration and treatment feasibility. The framework directly addresses the current uncertainty in determining when existing roadside soils and vegetative cover can meet stormwater performance requirements and when engineered treatment facilities are necessary. By enabling systematic identification of locations where existing soils provide sufficient infiltration and contaminant attenuation, this project may assist with (1) reducing unnecessary engineered stormwater treatment facilities that require construction costs, operational costs and long-term maintenance commitments, and (2) reducing the need to acquire additional ROW to install engineered facilities, minimizing both project delivery and O&M costs. Even if additional ROW may be needed to fit the natural areas for treatment, long-term operation and maintenance costs will likely be reduced.]]></description>
      <pubDate>Wed, 08 Jul 2026 17:25:51 GMT</pubDate>
      <guid>https://rip.trb.org/View/2726138</guid>
    </item>
    <item>
      <title>Improving Stormwater Systems for Debris and Contaminant Capture</title>
      <link>https://rip.trb.org/View/2712206</link>
      <description><![CDATA[Highway runoff carries a complex mix of pollutants, including debris, heavy metals, and nutrients. Oil, grease, and combustion byproducts from vehicles further add to the contaminant load. In addition to these conventional pollutants, scientific advances have highlighted contaminants of emerging concern (CECs) that were not fully recognized when most departments of transportation’s (DOT’s) stormwater programs were first developed.

Unlike conventional pollutants that degrade over time, many of these debris and CECs persist. They clog inlets and ponds, reduce hydraulic conductivity, and increase pollutant loads to downstream waters. For DOTs, this creates two major challenges: rising costs to maintain stormwater assets, and regulatory risk under municipal separate storm sewer system permits if pollutant control cannot be demonstrated.

The objective of this research is to develop a guide for reducing broad pollutants, which include macro-debris, microplastics, and tire wear particles, which have been demonstrated to contain compounds toxic to certain aquatic organisms.]]></description>
      <pubDate>Wed, 10 Jun 2026 11:28:41 GMT</pubDate>
      <guid>https://rip.trb.org/View/2712206</guid>
    </item>
    <item>
      <title>Design of Stormwater BMPs for Surface and Groundwater Protection Based on Site-Scale Soil Properties: Phase II</title>
      <link>https://rip.trb.org/View/2706364</link>
      <description><![CDATA[The objective of this project is to optimize the nitrogen (N) and phosphorus (P) removal potential of stormwater basins by improving the ability to predict the performance of common native soil properties alone, or with a BAM amendment, and using two planting specifications typically utilized in Florida Department of Transportation (FDOT) maintenance. Phase II will build upon the findings of Design of Stormwater BMPs for Surface and Groundwater Protection Based on Site-Scale Soil Properties: Phase I BDV24-977-43 (hereafter referred to as “Phase I”), which demonstrated the superior performance of unamended native soils with moderate soil organic matter and clay contents in the removal and sequestration of N and P during short-term laboratory experiments. Specifically, the research team will leverage this knowledge in a new experiment with improved external validity through the use of outdoor mesocosms in a multi-year study (e.g., scaling-up in both space and time). Commonly encountered native Florida soils will be prepared and planted per FDOT specification in replicated stock tanks (e.g., ~300-500 gal), with or without a BAM blanket filter, and using at least two FDOT approved vegetative strategies. Inflow and outflow hydrology will be controlled to mimic wet and dry basin hydropatterns and real-time mass balance of nutrient transport/transformation. The plant-soil-microbial interactions will be investigated to determine optimal N and P removal rates under varied hydrology. This new empirical data will improve stormwater BMPs by more accurately assessing the potential of native site soils, planting, and amendment strategies to function in nutrient remediation at the project site scale.]]></description>
      <pubDate>Wed, 27 May 2026 10:39:28 GMT</pubDate>
      <guid>https://rip.trb.org/View/2706364</guid>
    </item>
    <item>
      <title>Quantifying the Flood Resilience Value of Water Quality Best Management Practices on Vermont Roads</title>
      <link>https://rip.trb.org/View/2689762</link>
      <description><![CDATA[Transportation networks have been recognized as contributors to water quality impairment by discharging stormwater, sediment, and nutrients to receiving waters. These contributions can occur through chronic inputs of water and pollutants washed from the road surface during storm events or through episodic and often catastrophic road failure by mass wasting or fluvial erosion at structure crossings during extreme storms. Research studies in forested areas of the eastern United States, and elsewhere, including those conducted by members of this project team, have documented rates of erosion and mass wasting from low volume roads and impacts on water quality. Our previous research has also documented the importance of unpaved roads on water quality impairment and quantified the effectiveness of best management practices (BMPs) in reducing sediment and phosphorus contributions.
The Phosphorus Total Maximum Daily Load for Vermont Segments of Lake Champlain (a.k.a. TMDL) called for reductions in phosphorus contributions from developed lands, motivating a need to address stormwater runoff from the state’s transportation network. Statewide efforts to achieve the reductions required by the TMDL led to the development of the Municipal Roads General Permit (MRGP) in 2018 and subsequent revisions. Recent extreme flooding events across the state, in particular the July 10-11, 2023 North Country Storm event and associated Great Vermont Flood which will be the focus of this project, in addition to subsequent flood events in December 2023 and July 2024, have resulted in the need for emergency repairs of damaged transportation infrastructure, and revealed the need to clearly communicate the cost benefit of improved stormwater management on the transportation network. In past research projects funded by the Vermont Department of Environmental Conservation and the Vermont Agency of Transportation, we conducted retrospective analyses (i.e. a review of project planning documents and site visits to assess existing conditions) of transportation stormwater upgrades funded by the state’s Better Roads and Grants in Aid programs and found that the BMPs installed through these grants were highly robust to extreme flood events. This project therefore aims to expand on the research teams’ prior work to assess the life cycle cost-benefit of BMP adoption with a focus on the BMPs required by the Municipal General Roads Permit (MRGP), Sections 1 and 2 of the VT Road and Bridge Standards for municipal roads, and VTrans Drainage Management Standards for State roads. The data and results of this project may be used to update VT AOT’s Transportation Resilience Planning Tool or other mitigation practices.
To facilitate this work, we will form a technical advisory committee (TAC) composed of VTrans project champions (Todd Eaton), Vermont Department of Environmental Conservation (VT DEC) staff engaged in the implementation of the Municipal Roads General Permit, members of at least one Regional Planning Commission, and others identified by VTtrans. The role of the TAC will be to help guide study design, facilitate the use of existing data, leverage on-going implementation of erosion control projects, and provide context for agency needs.]]></description>
      <pubDate>Wed, 08 Apr 2026 09:46:01 GMT</pubDate>
      <guid>https://rip.trb.org/View/2689762</guid>
    </item>
    <item>
      <title>Improved VDOT Bioretention Media Specification</title>
      <link>https://rip.trb.org/View/2672501</link>
      <description><![CDATA[Virginia Department of Transportation (VDOT) uses bioretention as a stormwater control measure (SCM); however, the most recent special provision for VDOT bioretention soil media requires that testing the media’s infiltration rate use a unique mesocosm test method, outlined in VTM-134 (VDOT, 2025), which presents five challenges.  These are (1) inconsistency in how the media is placed and ultimately compacted in the test apparatus and therefore potential variability in the test results; (2) lack of labs willing to run the mesocosm test (only one in Virginia does this); (3) large amount of media required (40 5-gallon buckets of media and related materials); (4) lack of information proving this test is needed to procure successful bioretention soil media; and (5) a cost of $6,000 to run one test.  Due to these challenges, few media providers both try to meet the requirements and then succeed in doing so, which ultimately increases the overall project costs when bioretention is selected as the SCM.  A unique aspect of testing a media’s infiltration rate using the mesocosm test is consideration of how both de-icing salts and wet and dry cycles (to mimic rainfall patterns) impact a media’s infiltration rate. These unique aspects of the mesocosm test appear to be why it’s included in the current special provision. This study will recommend a specification for VDOT bioretention soil media that addresses the five challenges of the mesocosm test method to determine the media’s infiltration rate based on laboratory testing.]]></description>
      <pubDate>Thu, 19 Feb 2026 10:50:44 GMT</pubDate>
      <guid>https://rip.trb.org/View/2672501</guid>
    </item>
    <item>
      <title>Innovative Stormwater Solutions for Linear Projects</title>
      <link>https://rip.trb.org/View/2486932</link>
      <description><![CDATA[Managing stormwater is a critical part of any transportation infrastructure project, both during construction and long term. Meeting water quality requirements during long linear projects is challenging given limited right of way and resources; this is especially true in tight urban areas. The increase in impervious surfaces has increased the amount of water that must be managed (as opposed to being absorbed into the ground). There are different types of challenges managing stormwater within urban and rural areas, each require different approaches and techniques. For each, the creation and maintenance of stormwater infrastructure have different implications for roadside infrastructure and vegetation. Finally, there are multiple different challenges that occur at different timeframes, from short term construction challenges to longer term infrastructure and maintenance concerns.]]></description>
      <pubDate>Wed, 08 Oct 2025 10:14:01 GMT</pubDate>
      <guid>https://rip.trb.org/View/2486932</guid>
    </item>
    <item>
      <title>Dynamics, Drivers and Mitigation of Submerged Aquatic Vegetation (SAV) and Shoreline Change: Data Needs Associated with the Mid-Currituck Bridge</title>
      <link>https://rip.trb.org/View/2604610</link>
      <description><![CDATA[Recent research (S.A.V.E. Currituck, 2020) has shown that in Currituck Sound, the primary factor limiting submerged aquatic vegetation (SAV) distribution is water clarity. SAV in the sound will likely be impacted by construction and shading post construction of the Mid-Currituck Bridge. In addition, studies have shown that shorelines near the Mid-Currituck Bridge terminus on the east and west side are experiencing significant erosion rates. Bridge design and ultimate construction may change local dynamics (i.e., wave field, water clarity) that can influence SAV distribution and shoreline position. This project has three primary objectives relevant to understanding water quality, SAV and shoreline mitigation strategies: (1) Quantify temporal and spatial changes in water quality, specifically CDOM abundance in surface waters of northern Currituck Sound; (2) evaluate shoreline change rates on multiple timescales, including influence of storms, near bridge landing; and (3) synthesize remote sensing and field data to provide information to limit impacts to water quality, SAV and shorelines during bridge construction and maintenance and to prioritize mitigation for maximum benefit. It is critical to have more information on the current local water quality, shoreline change and SAV dynamics to better predict and limit damage associated with bridge construction and to prioritize required mitigation activities for maximum benefit. This research will focus on expanding data collection near the bridge corridor and broadening understanding of water clarity/quality dynamics and its potential role in changing SAV distribution.]]></description>
      <pubDate>Tue, 30 Sep 2025 14:53:37 GMT</pubDate>
      <guid>https://rip.trb.org/View/2604610</guid>
    </item>
    <item>
      <title>A Multi-Criteria Framework for Selecting Nature-Based Solutions for Remnant Properties for Regulatory Credit</title>
      <link>https://rip.trb.org/View/2604609</link>
      <description><![CDATA[The primary objective of this research is to develop and implement a robust multi-criteria decision support framework to enable the North Carolina Department of Transportation (NCDOT) to strategically leverage remnant properties as nature-based solutions for regulatory credit under the Department’s statewide National Pollutant Discharge Elimination System (NPDES) stormwater permit (NCS000250) and under state nutrient management strategy rules. In recent years NCDOT has experienced a significant escalation in construction costs, including costs associated with designing and constructing stormwater control measures along existing highways as is required by Section 3.6.1 of the NPDES stormwater permit and 15A NCAC 02B .0281 (9)(d) of the Falls Lake nutrient management strategy rules. In an effort to control construction and long-term maintenance costs, NCDOT piloted a project to retain ownership of four adjacent remnant parcels in Division 5 (Falls Lake watershed) and quantify the stormwater management benefits of maintaining the parcels in an undeveloped land cover. The NC Department of Environmental Quality formally recognizes land conservation as a creditable compliance practice and NCDOT demonstrated that the pilot project saved the Department $3,500,000 in avoided design, construction, and long-term maintenance costs of stormwater infrastructure relative to the value of the properties if sold on the open market. The success of the pilot project in Division 5 has demonstrated that remnant properties from right-of-way acquisitions provide a unique opportunity to provide a value-added repurposing of underutilized assets. The aim of this framework is to align NCDOT's stormwater management compliance obligations with the untapped potential of remnant properties by achieving regulatory compliance, environmental sustainability, cost-effectiveness, social impact, and asset optimization through the strategic deployment of nature-based solutions (NBS).
To achieve this objective, the research begins with a systematic literature review, identifying best practices and relevant frameworks in stormwater management and NBS. The research team will then conduct expert interviews and surveys to engage NBS experts and practitioners. Next, the team will conduct outreach activities to engage NCDOT stakeholders, ensuring their valuable input is incorporated into the decision-making process. Then the team will collate the knowledge gained in these tasks to develop an adaptable, data-driven decision support framework. Lastly, the team will use the newly developed framework to conduct real-world case studies that will test the framework's efficacy, including sensitivity analysis to ensure robustness and flexibility. By combining scientific rigor, expert input, stakeholder engagement, and practical application, the research approach aims to produce a tool bridges the gap between sustainability and effective stormwater management.
This research holds significant importance for both NCDOT and the broader community. It positions NCDOT as a leader in sustainable stormwater management, leveraging remnant properties to reduce costs, enhance environmental stewardship, engage communities, and meet regulatory obligations. Anticipated outcomes include a versatile decision support tool that can be adapted for various scenarios, insights from case studies that provide real-world applicability, and sensitivity analysis results to ensure the framework's robustness. Ultimately, the research empowers NCDOT to make informed decisions that benefit economic efficiency, ecological health, and social well-being in the realm of stormwater management, setting a precedent for sustainable practices in transportation agencies.]]></description>
      <pubDate>Tue, 30 Sep 2025 14:04:14 GMT</pubDate>
      <guid>https://rip.trb.org/View/2604609</guid>
    </item>
    <item>
      <title>Traversable Postconstruction Stormwater Check Dams in Clear Zones


</title>
      <link>https://rip.trb.org/View/2558390</link>
      <description><![CDATA[State departments of transportation (DOTs) must comply with stormwater discharge requirements under the Clean Water Act. Clear zones within the highway right-of-way often provide suitable locations for stormwater management close to the source of runoff. Roadway swales with check dams are a common, cost-effective solution for stormwater quantity and quality control in these clear zones. 

Current guidelines do not provide recommendations for the design of check dams in clear zones. Additionally, check dam design must be compatible with the primary purpose of clear zones: vehicular safety. Concerns have been raised about check dams causing vehicles to vault into oncoming traffic or rollovers. Research is needed to support the development of check dam design specifications that meet state DOT safety requirements and to help achieve water quality goals.

The objective of this research is to develop a guide and accompanying site assessment decision support tool for designing traversable postconstruction check dams in clear zones. ]]></description>
      <pubDate>Wed, 28 May 2025 13:28:45 GMT</pubDate>
      <guid>https://rip.trb.org/View/2558390</guid>
    </item>
    <item>
      <title>Dynamics, Drivers and Mitigation of Submerged Aquatic Vegetation (SAV) and Shoreline Change: Data Needs Associated with the Mid-Currituck Bridge</title>
      <link>https://rip.trb.org/View/2422895</link>
      <description><![CDATA[Research has shown that in Currituck Sound the primary factor limiting submerged aquatic vegetation (SAV) distribution is water clarity. Data collection in the last several months has suggested an expansion of SAV in some shallow regions of Currituck Sound. An understanding of SAV depth distribution and light availability in this system has provided water depth zones to differentiate the likelihood of sustaining planted SAV. Changes in water clarity driven by Colored Dissolved Organic Matter (CDOM) is likely changing SAV growth on annual timescales. In addition, shoreline erosion is likely affecting water clarity and certainly will influence construction along the banks. SAV in the sound will likely be affected by construction and shading post construction of the Mid- Currituck Bridge. In addition, studies have shown that shorelines near the Mid-Currituck Bridge terminus on the east and west side are experiencing significant erosion rates. This research will focus on expanding data collection near the bridge corridor. The project will further develop the SAV mitigation tool by collecting the necessary higher resolution data (e.g., shoreline position, bathymetry, SAV presence, proximity to existing vegetation, water quality/clarity) to focus future SAV mitigation sites.]]></description>
      <pubDate>Thu, 29 Aug 2024 08:29:20 GMT</pubDate>
      <guid>https://rip.trb.org/View/2422895</guid>
    </item>
    <item>
      <title>Assessing Effectiveness of Pond Sediment Removal for Phosphorus Management in Stormwater Ponds</title>
      <link>https://rip.trb.org/View/2387527</link>
      <description><![CDATA[Stormwater ponds are plentiful in Minnesota and can be useful in treating stormwater runoff. Some ponds, however, can re-release phosphorus. This project will investigate the effectiveness of sediment removal in improving stormwater quality and reducing phosphorus downstream. It will also explore if sediment should be treated to reduce phosphorus release during dredging.]]></description>
      <pubDate>Fri, 07 Jun 2024 09:25:26 GMT</pubDate>
      <guid>https://rip.trb.org/View/2387527</guid>
    </item>
    <item>
      <title>Methods to Measure Emerging Contaminants in Stormwater

</title>
      <link>https://rip.trb.org/View/2381713</link>
      <description><![CDATA[Recent data on emerging contaminants has prompted state departments of transportation (DOTs) and water authorities to explore significant investments in stormwater sampling and treatment infrastructure. This proactive approach aims to more fully understand the occurrence and impact of emerging contaminants and the effectiveness of stormwater treatment systems. By gathering this data, decision-makers can offer more accurate, informed strategies for managing stormwater, leading to more efficient design, construction, and maintenance of treatment systems.

Research is needed to determine the methods and materials needed to measure concentrations of emerging contaminants in runoff, stormwater-treatment system effluent, and receiving waters to support cost-effective quantitative threat assessments and treatment decisions. 

OBJECTIVE: The objective of this project is to develop recommended practices for state DOTs for assessing sampling methods used to measure emerging contaminants as well as new contaminants identified in the future. ]]></description>
      <pubDate>Tue, 21 May 2024 15:52:38 GMT</pubDate>
      <guid>https://rip.trb.org/View/2381713</guid>
    </item>
    <item>
      <title>Evaluating a Two-Stage Roadside Ditch Design to Improve Environmental Performance</title>
      <link>https://rip.trb.org/View/2346392</link>
      <description><![CDATA[Conventional trapezoidal roadside ditches are designed to rapidly deliver runoff, sediment and nutrients to downstream surface water but they can be impacted from erosional downcutting and excessive sedimentation. In agricultural regions, ditches have been modified with a two-stage design that involves modifying the conventional trapezoidal ditch into one that better replicates the features of a natural stream through the addition of adjacent benches. The two-stage design reduces bank slumping and undercutting during high flows while improving water quality by trapping and treating runoff water flowing through them. The objectives of this project are to evaluate the performance of a two-stage roadside ditch constructed along a selected roadway and evaluate its stability and long-term maintenance requirements in Iowa conditions. In this project, the team will work closely with DOT and a Technical Advisory Committee (TAC) to select, model, design, construct, and monitor a two-stage ditch prototype. The monitoring protocols will be adapted for the conditions at the prototype construction site and include treatment-control scenarios either as upstream-downstream or paired designs. Continuous discharge and turbidity measurements will be used to capture stormwater runoff loads whereas regular grab samples will be collected and analyzed for baseflow changes in water quality parameters including nutrients and sediment. Stability and maintenance will be assessed through annual field evaluations and drone surveys. At the conclusion of the project the research team will present the research in a final report that evaluates the performance of a new design for roadside ditches, based flow conveyance, stability of the road infrastructure, and capacity to retain sediment and improve downstream water quality. A series of practical recommendations will be provided that summarizes the major findings of the study on the performance and efficiency of the proposed two-stage design and illustrates the lifecycle cost benefits resulting from the new design implementation.]]></description>
      <pubDate>Wed, 28 Feb 2024 17:38:54 GMT</pubDate>
      <guid>https://rip.trb.org/View/2346392</guid>
    </item>
    <item>
      <title>Field and Laboratory Evaluation of Roadside Soil Quality Restoration Practices</title>
      <link>https://rip.trb.org/View/2344961</link>
      <description><![CDATA[Stormwater control measures (SCMs) are important to mitigate the stormwater quantity and quality of land development on roadsides. Runoff from impervious pavement surfaces creates a substantial disturbance to natural hydrologic processes. Many options are available to manage stormwater on roadsides including detention basins, bioretention basins, and permeable pavements. However, these structural-based practices are costly to build and maintain. An alternative cost-effective SCM is to restore the quality of the existing roadside topsoil. In the proposed study, various cost-effective soil quality restoration treatments will be evaluated to effectively manage stormwater runoff on roadsides. The main goal of this research project is to quantify the improvements for vegetation establishment and subsequent stormwater volume reduction by the proposed soil quality restoration treatments. The research methodology involves conducting both field and greenhouse experiments to determine the selection and mixing ratios of different cost-effective additives such as composts, proprietary soil amendments, and biochars for rapid restoration of roadside soil quality. This work will also investigate the impact of soil compaction and tillage effects on roadside soil quality restoration. Primary tasks for the project will be the development of a specification and implementable guidance for these restoration techniques. The objectives will be achieved in six phases: (1) review of current Iowa DOT practices; (2) collection and determination of the physicochemical properties of the soils and additives mentioned above; (3) greenhouse study; (4) construction and monitoring of field plots; (5) cost analyses; and (6) development of an implementable guideline to help in the selection of the proper additive materials and mixing ratios, and construction and maintenance methods (e.g., mower type and mowing frequency) for roadside soil quality restoration in terms of performance and cost-benefit. The outcome of this research in the form of a construction guideline and a design specification could be immediately implemented by Iowa DOT.
]]></description>
      <pubDate>Tue, 27 Feb 2024 19:29:09 GMT</pubDate>
      <guid>https://rip.trb.org/View/2344961</guid>
    </item>
    <item>
      <title>Stormwater Management to Address Highway Runoff Toxicity Due to 6PPD-Quinone from Tire Rubber</title>
      <link>https://rip.trb.org/View/2265694</link>
      <description><![CDATA[The current method for extending tire longevity by preventing tire-rubber cracking and degradation includes the addition of the chemical additive 6PPD. With tire wear and atmospheric ozone exposure 6PPD oxidizes to form 6PPD-quinone (6PPD-q). Recent research has demonstrated toxicity of 6PPD-q for at least one Endangered Species Act listed aquatic threatened and endangered species, coho salmon, with potential for toxic impacts to other aquatic species, including rainbow trout/steelhead and brook trout. These findings will likely result in regulatory agencies imposing stormwater treatment requirements for 6PPD-q on highway projects as well as raising questions regarding state DOTs’ use of pavements containing recycled-tire-rubber materials. This research aims to equip state departments of transportation (DOTs) with a targeted approach for effectively managing 6PPD-q in highway runoff by (1) developing methods/criteria for identifying locations that need focused treatment, (2) developing a better understanding of the fate and transport of 6PPD and 6PPD-q, (3) developing cost-effective design guidance for stormwater treatment and management techniques with a focus on reducing the effects of 6PPD-q on receiving waters, and (4) evaluating the degree of 6PPD-q release from pavement products made from recycled tire materials. This research will also assist with providing regulatory agencies with a better understanding of DOT management options including the feasibility, limitations, and effectiveness of treatment methods.]]></description>
      <pubDate>Tue, 10 Oct 2023 15:32:54 GMT</pubDate>
      <guid>https://rip.trb.org/View/2265694</guid>
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