Interactive Sediment Remedy Assessment Portal
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1. What is the Matrix?
 The Matrix is an interactive web portal that can be used to identify monitoring needs and candidate monitoring tools for dredging, capping, and monitored natural recovery (MNR) monitoring programs. The matrices provide a decision-making framework with the following objectives:
  1. Provide a comprehensive list of monitoring needs.
  2. Identify monitoring tools associated with each monitoring need.
  3. Enable a screening-level comparison of tools when several are available for particular a monitoring need.
  4. Help RPMs focus on key issues associated with site-specific monitoring needs and tools, to facilitate the design of cost effective, and meaningful monitoring plans.

The ISRAP Matrix may be useful to understand monitoring needs and monitoring tools at any stage in the process of site investigation or remedial processes.

2. How does the Matrix work?
 The matrix narrows the amount of information presented to the user through a series of steps arranged in the following hierarchy:
  • Remedy
    • Monitoring Phase
      • Monitoring Need
        • Monitoring Tool and Monitoring Design

The final step in the matrix presents a comparative table of monitoring tools (containing monitoring design information and details) for a particular monitoring need associated with a remedy.

3. How do I select more than one remedial action?

This feature is not available. For sites with more than one remedy, or where remedies may be combined (such as MNR and capping in the case of Enhanced MNR), first explore monitoring tools and approaches associated with the primary remedy, then repeat the process starting at Step 1 with the other remedy.  Monitoring tools can then be compared for both remedies to maximize efficiency of the monitoring program.

4. What are the remedies?
There are three remedies covered by the matrix:
  1. Capping: An engineered sediment remedy involving the placement of a subaqueous covering or cap of clean material over contaminated sediment; the cap physically isolates contaminated sediment to reduce exposure through direct contact and stabilizes contaminated sediment to protect against erosion, resuspension, and transport.
  2. Dredging: The mechanical or hydraulic removal of sediments from the aquatic environment.
  3. Monitored Natural Recovery (MNR): A remedy that involves leaving contaminated sediments in place and allowing ongoing physical, chemical and biological processes to reduce contaminant exposure to receptors through physical isolation, dispersion, offsite transport, chemical transformation and/or reduction in bioavailability.  MNR is not a passive process, as it incorporates extensive monitoring to document the performance of natural recovery processes.
5.What about thin layer capping (TLC) or dredging backfill? How do I investigate monitoring needs and tools associated with these remedies?
Thin layer placement and dredging backfill applications rely on natural recovery processes associated with MNR and isolation mechanisms associated with traditional isolation capping. In some cases, these applications may be referred to as Enhanced Monitored Natural Recovery (EMNR). When thin layer placement, dredging backfill, or EMNR approaches are used, users should investigate monitoring needs and tools associated with both Capping and MNR remedies in the matrix, as both could be applicable to these hybrid approaches.
6. What are the monitoring phases?
  1. Compliance (Construction): Construction monitoring includes assessment of construction and operations activities, potential adverse conditions associated with remediation construction, and attainment of design criteria.
  2. Compliance (Performance): Performance monitoring includes determining the extent to which the remedy achieves primary performance goals such as sediment removal (dredging), sediment isolation (capping and MNR), and chemical transformation (MNR).
  3. Remedial Goal: Remedial goal monitoring provides an assessment of the extent to which the sediment remedy achieves remedial action objectives that are the ultimate goals of sediment management: the reduction of human and ecological risks.
The relationships between monitoring phases are illustrated on the below timelines for Dredging, Capping, and MNR:


Dredging Timeline 


Capping Timeline


MNR Timeline

7.Why isn’t there a choice for the Performance phase of Dredging?
Performance monitoring data is used to answer the question: Is the remedy mechanism performing as designed? Performance monitoring is absent from dredging, as there is no ongoing remedy mechanism responsible for risk reduction once construction activities are complete.
8. Why isn’t there a choice for the Construction phase of MNR?
 MNR is a non-invasive remedy that does not require an active construction phase. Thus, construction-related risks and evaluation of construction practices are not an issue with MNR.
9. Are all of the needs and tools applicable to all sites?
 The matrices do not include all remedy functions or critical monitoring questions. Conversely, the example tools and needs in the matrices address a wide spectrum of stakeholder concerns and remedial goals that are not likely to be relevant for all (or even most) sites. Examples are included to illustrate a possible range of monitoring tools and needs.

RPMs should keep the following in mind while browsing the Matrix to select relevant monitoring phases, needs, and tools:

  1. Site conditions
  2. Chemicals of concern
  3. Risk-drivers and Remedial Action Objectives
  4. Stakeholder concerns
10.What does monitoring tool “Type” mean?

Sediment monitoring tools are identified according to the following classifications:

  1. Physical testing may include measurements of sediment erosion or deposition, ground water advection, surface water flow, and physical characteristics of the sediment (e.g., particle size distribution (PSD), porosity, organic carbon content), and sediment heterogeneity. Most physical endpoints are relatively straightforward to measure and interpret.
  2. Chemical measurements involve collecting sediment, pore water, surface water, and biota samples and analyzing those samples for chemical concentrations or other chemical measurements. Chemical tools also include methods to measure water quality variables such as organic carbon content, pH, dissolved oxygen, or hardness.
  3. Biological measurements involve biological and toxicological monitoring tools involving site and/or laboratory organisms. Biological monitoring tools are often used to evaluate ecological risks, evaluate restoration effectiveness, and determine bioaccumulation.
11.What does “More” mean on the “Monitoring Tools” Page?
 Clicking the magnifying glass under “More” will open a popup window with links to more detailed information about that particular tool.
12.What do low, med, high mean on the “Monitoring Design” Page?
 See Appendix B of the Sediment Monitoring Guidance for more information.
13.What about monitoring need ____ or monitoring tool ____? Some monitoring tools and needs appear to be missing.
The matrices do not include all remedy functions or critical monitoring questions, monitoring needs, or monitoring tools. The ISRAP matrix will be updated periodically.
14.Are there any case studies explaining how this guidance and approach would apply to real-world sites?
See Appendix C of the Sediment Monitoring Guidance for case studies.
15.Where do I find information about statistics and models for interpreting data and planning a monitoring design?
See Appendix D of the Sediment Monitoring Guidance for more information.
16.How do I choose a tool?
The ISRAP provides users with a variety of possible monitoring tools to address a given monitoring need. Not all tools are best suited for all monitoring scenarios, and it is possible that other tools not listed for a given need in the ISRAP may be useful. Users should apply knowledge of the site, overall monitoring objectives, stakeholder concerns, remedial action objectives, consideration of tools used for prior site characterization or monitoring activities, plus the information provided in the ISRAP to explore possible tools. Ultimately, the ISRAP provides guidance for obtaining more information in selection of a monitoring tool. Selection of the tool must be made while considering the monitoring scenario specific to the site.
17.How Should Pre-Construction and Baseline Monitoring data be included in the analysis?
Baseline monitoring is used to augment the data on existing conditions following site characterization and remedial design activities conducted as part of the RI/FS. Baseline monitoring establishes a database for planning or future comparisons, and is a key part of the monitoring program associated with any remedy. The intent of baseline monitoring is to establish initial conditions against which changes can be compared, augmenting site characterization data.

Just as pre-remedial data provides a baseline for comparison with remedial goal monitoring post-remedy baseline conditions must be established immediately after remediation to establish post-remediation baseline conditions to compare with long-term recovery data. Depending on the site, it may be necessary to establish baseline conditions with respect to contaminant chemistry, ecological conditions, and physical conditions.

The quantity and quality of site characterization data must be evaluated prior to designing a monitoring program to ensure that the data are robust and the site is well characterized with respect to the endpoints of interest. Site characterization data collected during the RI/FS may need to be supplemented with additional data more aligned with long-term monitoring goals. RI data may need to be supplemented with new data for sites where RI data is old or at sites where the RI data does not adequately provide a baseline. To the extent possible, monitoring approaches (including monitoring tools) should be similar (or identical) in pre- and post-remediation monitoring programs to facilitate direct data comparison.

Following the selection of monitoring needs and examination of monitoring tools, one should evaluate the need for baseline data using the selected monitoring tools. Sufficient baseline data should be collected to enable a robust “before and after” comparison.
18.Why can't I see the Slideshow?
 The slideshow uses Adobe Flash Player, a common plugin for web browsers.  To download the plugin please visit:
19.How should information in the ISRAP be cited?
Information provided in the guidance text or online matrices should be cited as follows:

Space and Naval Warfare Systems Center Pacific and ENVIRON International Corporation. 2010. Long-Term Monitoring Strategies for Contaminated Sediment Management. Final Guidance Document. .
20.Why do I sometimes not get the correct page in the EPA Fact Sheets?
There is a known bug in certain versions of Adobe Acrobat 7 in combination with Internet Explorer 7 that results in the wrong page being returned, under certain situations.  The problem has apparently been addressed in later releases of version 7, and version 8.0.