DNREC’s response to Mr. Price’s comments are shown in italics below the comment.

1)    The duration of the public comment period is 20 days however the start date shown on the newspaper advertisement and electronic notice on your website spans from February 15-March 6; that’s only 19 days.

The comment period starts on the day that the Amended Proposed Plan of Remedial Action is advertised which was February 15 and ends on March 6, that makes the duration 20 days. However, DNREC is extending the comment period to March 7, 2017 due to the confusion. 

2)    Page 3 – the discussion that the remedy document required one year of groundwater monitoring to show that dissolved lead wasn’t significantly migrating appears to be inadequate. Have groundwater conditions such as gradient, flowrate, and transmissivity been adequately characterized to make this determination? What is the basis of the determination (was it a rule of thumb or were groundwater studies conducted)?

The Amended Proposed Plan is meant to be a summary of the information and Site decisions. The basis for this determination is the fact that dissolved lead concentrations had dropped from 2004 to 2016 at the source while the downgradient wells had not exceeded screening levels.  Detailed information is included in the following relevant documents:

·         6/7/07 Supplemental Investigation Report 

·         August 12, 2014 Request to Re-Evaluate Remedy. This document was not available online at that time. However, now it is added.  DNREC is providing you with a copy.

3)    Page 3 2^nd to the last paragraph – the discussion referred to testing for total and dissolved lead in groundwater samples, were those samples filtered?

            Samples discussed in the proposed plan were filtered (dissolved) and unfiltered (total).

4)    Page 3 last sentence states “The only risk from groundwater is from drinking water from a well located on the Site.” That suggests that there is a well but there isn't one there so possibly clarify this sentence by adding the phrase “if there was a drinking water well installed at the site…”?

The interpretation is correct.  These comments and responses will be included in the Amended Final Plan to reflect this clarification.

5)    Page 3 2nd to the last sentence stated that there is dissolved lead in groundwater however it never exceeded standards in downgradient wells. What if the migration was slow, for example might those downgradient wells’ locations show dissolved lead criteria was exceeded in 10+ years? Has the rate of migration of dissolved lead been determined (see also comment 2 above)?

As noted in DNREC’s response to comments above, the dissolved lead concentrations did not change in the downgradient wells (all were below screening levels) between 2004 and 2016 even though the monitoring well closest to the source area decreased over the same time period. The facility was in existence since 1930s therefore the release could potentially be older than 2004. In addition, the distance between the source and the downgradient well is only 60 feet. Based on this information, DNREC concluded that the plume is stable and not migrating offsite.

6)      Page 4 the section “What is the environmental problem at the J.G. Townsend site?”, the second sentence states “The soil would present a risk only for residential use soil exposure.” This sentence is misleading because any industrial/commercial exposures to lead at also present risk. I’d suggest use of the word “risk’ in a less absolute manner and adding phrases like “soil lead concentrations are below commercial/industrial screening levels but above residential screening levels”.

The lead in soil is not causing an unacceptable risk under industrial/commercial scenarios and the use of the phrase “only for residential use” was meant to reflect that. These comments and response will be included in the Amended Final Plan to reflect this clarification.

            7)      Page 6 item 5 calls for destruction of groundwater monitoring wells, shouldn’t those be retained for long-term monitoring? (see also comments 2 and 5 above).

In Delaware, it is common practice to properly abandon wells when a Site is closed to avoid a potential future pathway for surface contaminants into groundwater. Further long term monitoring is not required for the site because the plume has stabilized and reducing in concentration.

8)      Page 6 has a link to your database and states that most documents can be found there. However the most important documents (e.g. a remedial action completion report and groundwater studies/monitoring reports) are missing and that prevented me from conducting a meaningful review. The listing of documents in the database for this site shows an email thread dated 12/16/15 which discussed groundwater testing and a “Remedial Action Work Plan” dated 4/1/09 which has useful information but not enough. Onto your website to allow for public viewing, please post the remedial action completion reports which describe the cleanup activities like excavation of contaminated soil with confirmation sampling results and lab sheets. Please also post groundwater studies and monitoring reports which show the basis of your determinations, and lab sheets. Alternatively if you could provide those via email that would be helpful.

Soil removal was not performed because re-evaluation of the lead risk using an updated USEPA risk calculator did not show a risk for industrial/commercial scenarios.  Since there was no removal, there are no confirmatory soil samples and no remedial action completion reports.  DNREC has since determined that two documents were inadvertently not posted online.  DNREC posted these documents on line and is providing you with a copy of both of those documents for your convenience.  

9) Since the property is planned to be restricted with a land use covenant shouldn't the area of planned restriction of groundwater be presented in this document?

Since the area of groundwater impact from lead is limited to the Site then restricting site use at the Site boundaries would limit any potential groundwater ingestion risks caused by drinking lead contaminated water.

10) Please extend the comment period to allow more time for review of the additional documents requested to be viewed electronically (on your website or via email) above.

As noted in DNREC’s response above, DNREC extending the comment period to March 7, 2017.

Thank you for your comments.

 From:

Thomas Price <This email address is being protected from spambots. You need JavaScript enabled to view it.> 2-25-17