# April 16, 2001

## Via Overnight Express Delivery

Ms. Shirley Diamond

Federal Center Associates

1250 Connecticut Avenue, NW

Suite 500

Washington, D.C. 20036

Subject: Consolidated Responses to Comments Dated

> August 10, 2000 and November 22, 2000
>
> Generated by U.S. EPA Region III
>
> Description of Current Conditions and Summary of Interim Measures/Site
> Stabilization -- Revision 2 and RFI Workplan Documents -- Revision 1
>
> Final Administrative Order on Consent
>
> U.S. EPA Docket No. RCRA-III-019AM
>
> Southeast Federal Center, Washington, DC
>
> Special Study No. SP-30, Modification No. 4

Dear Ms. Diamond:

In accordance with the Special Study No. SP-30 Modification No. 4, URS
Group, Inc. (URS) has reviewed comments dated August 10, 2000 and
November 22, 2000 generated by the U.S. Environmental Protection Agency
Region III (EPA) concerning the subject documents. Specifically, this
document presents responses to the following comments:

-   August 10, 2000 comments on the RFI Workplan Document: Data
    Collection Quality Assurance Plan (DCQAP), Part 2 - Quality
    Assurance Project Plan (QAPP) -- Revision 1, and

-   November 22, 2000 comments on the Description of Current Conditions
    and Summary of Interim Measures/Site Stabilization (DCC & IM/SS) --
    Revision 2 and Revision 1 of the following RFI Workplan Documents:
    DCQAP, Part 1 -- Field Sampling Plan (FSP) and Data Management Plan
    (DMP).

The term "RFI Workplan Documents" is often used throughout this letter.
The RFI Workplan for this project is composed of five documents,
including a DCQAP and DMP and three other documents: a Health and Safety
Plan (HSP), Community Relations Plan (CRP), and a Project Management
Plan (PMP). Also, the DCQAP is composed of two sections, a Field
Sampling Plan (FSP) and a Quality Assurance Project Plan (QAPP).

Our consolidated responses to EPA's comments are presented below. Our
responses, as appropriate, were discussed with, and agreed to by, Mr.
Steven Richard of the General Services Administration (GSA). Also,
comment responses similar to those presented herein were discussed with
representatives of the EPA during a February 22, 2001 meeting at their
office in Philadelphia, Pennsylvania. This meeting was attended by
representatives of the GSA and URS. As discussed at this meeting, the
GSA and URS were to reassess the locations of some of the RFI boreholes
and groundwater monitoring wells. Our reassessment resulted in proposing
that the following be eliminated from the RFI (refer to Figure 2-3 of
the FSP-Revision 1 for the locations of the sampling locations proposed
for elimination and Figure 2-3 in the enclosed FSP (Revision 2) for the
currently proposed sampling locations):

-   BC-SB/MW03 and BC-MW04: These two sampling locations were originally
    proposed for the purpose of investigating what impact, if any, the
    historic operation of a process pit in former Building 153 may have
    had on adjacent soil and groundwater. However, conflicting
    information indicated that this pit was either at the east or
    west-end of the building. In the enclosed version, and in Revision
    2, of the DCC & IM/SS, information and photographs place the process
    pit at the west end of Building 153 and sampling locations
    BC-SB/MW01 and BC-MW02 are proposed for the purpose of investigating
    the documented location of the pit. Therefore, we recommend that
    proposed sampling locations BC-SB/MW03 and BC-MW04 be eliminated
    from the RFI.

```{=html}
<!-- -->
```
-   BE-SB/MW02 (BE2) and BE-SB/MW04 (BE4): These two locations were
    originally proposed for the purpose of investigating what impact, if
    any, the historic vehicle maintenance operations in former Building
    216 may have had on underlying soil and groundwater. In the proposed
    RFI, two soil borings, BE-SB01 and BE-SB03, are to be installed
    approximately 40-feet north (topographically upgradient) and two
    more soil borings, BE-SB05 and BE-SB06, approximately 75-feet south
    (topographically downgradient) of locations BE2 and BE4. Also, two
    groundwater monitoring wells, BE-SB/MW07 and BE-SB/MW08 are proposed
    to be installed approximately 110-feet south (topographically
    downgradient) of locations BE2 and BE4. The four soil borings and
    two groundwater monitoring wells are all within the footprint of
    former Building 216. Therefore, we are of the opinion that there is
    sufficient coverage of the area of concern without proposed sampling
    locations BE2 and BE4 and recommend that they be eliminated from the
    RFI.

```{=html}
<!-- -->
```
-   J-SB/MW01: This proposed sampling location is approximately 25-feet
    west (topographically cross-gradient) of another groundwater
    monitoring well location, J-SB/MW02. These two proposed sampling
    locations, along with five other proposed locations (J-SB03, J-SB04,
    J-SB05, J-SB06, and J-SB/MW07)south (topographically downgradient)
    of them, were originally proposed for the purpose of investigating
    what impact, if any, the historic operations conducted in and around
    Building 74 may have had on underlying soil and groundwater. We are
    of the opinion that location J-SB/MW02, along with the three
    proposed sampling locations to the south, will adequately
    characterize the area of concern. Also, proposed sampling location
    J-SB/MW08 is northwest of J-SB/MW01 and J-SB-MW02 and thus should
    provide useful groundwater flow information in the absence of
    J-SB/MW01. Therefore, we recommend that proposed sampling location
    J-SB/MW01 be eliminated from the RFI.

-   M1-SB02: This proposed sampling location is between two other
    sampling locations, one approximately 15-feet north (M1-SB01) and
    the other (M1-SB03) approximately 15-feet south. We are of the
    opinion that the locations north and south of M1-SB02 will serve to
    adequately characterize the extent of remaining Trichloroethene in
    soil at the west-end of excavation Area M-1. Therefore, we recommend
    that proposed sampling location M1-SB02 be eliminated from the RFI.

-   O2-SM/MW07: This proposed sampling location was originally intended
    to serve to characterize general soil and groundwater conditions at
    the western edge of former Building 137 (the Steel Foundry).
    Downgradient of this location are two newly proposed soil
    boring/monitoring wells: O2-SB/MW07 and O1-SB/MW02. We are of the
    opinion that these locations will serve to adequately characterize
    general soil and groundwater conditions adjacent to the former Steel
    Foundry as well as the impact historic operations at the two
    previously undocumented buildings may have had on the subsurface
    (Buildings 144 and 177). Therefore, we recommend that proposed
    sampling location O2-SB/MW07 be eliminated from the RFI.

The changes discussed above are reflected in the enclosed FSP.

Included with this submission is one copy of Revision 2 of the DCQAP,
DMP, HSP, and PMP; the proposed final version of the CRP; and the
proposed final version of the DCC & IM/SS report that incorporates the
revisions discussed below. **This submission includes two versions of
each document -- a version entitled "Redline Version" that shows text
deletions in red and text additions in blue, and a version that depicts
the document with all changes shown in the "Redline Version" instituted.
Also, only Volume 1 of the DCC & IM/SS has been reproduced minus all
large size figures (figures inserted in yellow pockets). Adhesive-backed
covers for Volumes 2 and 3 of the DCC & IM/SS are also included. The
reader is requested to perform the following tasks:**

1.  **Remove all large size figures contained in the yellow pockets of
    Volume 1 of the DCC & IM/SS -- Revision 2 and place them in the
    yellow pockets of the proposed Final version of Volume 1, and**

2.  **Remove the adhesive backing from the enclosed covers for Volumes 2
    and 3 of the DCC & IM/SS and place them over the covers of Revision
    2.**

**The reader is also requested to perform the following task:**

1.  **Remove the first large size figure (Figure 2-2) and the third
    (Figure 10-1) contained in the yellow pockets of Revision 1 of the
    FSP and place them in the yellow pockets of the enclosed Revision 2
    of the FSP.**

Proposed Final versions of the CRP and DCC & IM/SS are enclosed. The CRP
is proposed as final because all outstanding responses to comments were
reviewed by EPA and were stated to be "satisfactory" in EPA's November
22, 2000 letter. The DCC & IM/SS is proposed as final because we are of
the opinion that all outstanding comments have been responded to in a
manner that is satisfactory to the EPA.

In order for the GSA to meet the April 16, 2001 submission deadline to
the EPA, URS is delivering nine copies of this letter; Revision 2 of the
DCQAP, DMP, HSP, and PMP; and the Final version of the CRP and DCC &
IM/SS (1 for GSA, 2 for GSA to send to the District of Columbia, and 6
for GSA to send to the EPA) directly to Mr. Steven Richard.

The following includes all outstanding comments and our responses:

**[AUGUST 10, 2000 COMMENTS ON RESPONSE TO COMMENTS: DCQAP PART 2: QAPP
-- REVISION 1]{.underline}**

**Note to reader:** All comments presented in the August 10, 2000 letter
as "Response Satisfactory" are not included in the following list of
comments. No further action was required for those comments.

**Comment No. 1:** As to the issue of choosing a laboratory, this
deficiency has been adequately addressed. However, with the addition of
Pace as a subcontractor laboratory, other issues have arisen. The
following should be addressed in the QAPP:

1.  The QAPP should specify which analyses will be performed by Pace and
    which by Phase Separation Science.

2.  How is the chain of custody to be handled for analyses being
    performed by Pace? This is an issue because of holding time and
    tracking. It is recommended that samples be shipped directly to Pace
    from the field especially since the EnCore^TM^ sampler is proposed
    to be used for soil volatile sampling. The chain of custody
    regarding the subcontracted laboratory needs to be addressed in the
    QAPP.

3.  A review of Pace's LQAP has been completed. The following are
    deficiencies/issues that need to be addressed in Pace's LQAP.

```{=html}
<!-- -->
```
a.  It appears from Table 6.2 that Pace does not have holding times for
    EnCore^TM^ sampling without preservation. This table needs to be
    revised to include EnCore^TM^ sampling without preservation, if it
    is intended that Pace will be performing volatile analysis on soil
    samples collected with the EnCore^TM^ sampler.

b.  Tables 9.1 and 9.2 in Pace's LQAP do not include EPA methods
    publication "Methods for the Determination of Metals in
    Environmental Samples", which contains the metals method 200.8;
    however in an addendum to Pace's LQAP, there is table that lists
    "Routine Analytical Products". In this table method 200.8 is listed.
    Table 9.1 and 9.2 should be revised to include the above
    publication. The methods to be used in this project are listed under
    the "Routine Analytical Products" table; however, Pace's LQAP should
    include sample extraction and/or digestion/extraction procedures,
    method detection limits (MDLs), practical quantitation limits
    (PQLs), precision, accuracy, calibration standards (identification
    and frequency) for the analyses being performed for this project.
    Without this information, it cannot be determined if the project
    objectives can be met.

**Response to Comment No. 1:** Phase Separation Science, Inc. (PSS) will
conduct all Appendix IX Inorganics, Appendix IX Organochlorine
Pesticides, and investigation derived waste characterization analyses.
Pace Analytical Services, Inc. (Pace), as a subcontractor to PSS, will
conduct all Appendix IX Volatiles and Appendix IX Semivolatiles
analyses. Clarification as to which laboratory will perform which
analyses has been provided in the enclosed Revision 2 of the QAPP
(Section 3.3, Section Three, and Tables 7-1 through 7-4).

Samples that are to be analyzed by Pace will be delivered directly to
their sample receiving department to avoid holding time conflicts
minimize chain-of-custody transfers. This modified procedure has been
included in the enclosed Revision 2 of the FSP (Table 5-1 and Section
6.1).

Pace's Table 6.2 was not revised to include holding times for EnCore^TM^
sampling without preservation because all solid samples collected for
Appendix IX Volatiles analysis will be preserved in the field and then
shipped to Pace for extraction and analysis. This procedure is described
in Section 3.7.2 of the enclosed FSP.

PSS will perform the analytical method 200.8 for analysis of metals in
samples. PSS and Pace will adhere to the accuracy and precision
requirements specified in the QAPP in conjunction with those specified
by the method they are performing. Pace, as a subcontractor to PSS, will
follow elements of the RFI QAPP applicable to those
extraction/digestions and analyses they perform as well as the
calibration standard identification and frequency procedures specified
in PSS's Quality Assurance Plan (Appendix A of the enclosed QAPP).
Method Detection Limits (MDLs) and Practical Quantitation Limits (PQLs)
listed in Tables 7-1 through 7-4 of the QAPP have been supplied by the
laboratory that will perform the particular analysis. These
clarifications have been incorporated into the enclosed Revision 2 of
the QAPP.

**Comment No. 2:** Table 7-4 in attachment 3 needs to be revised. Method
200.8 is not a SW-846 Method. Method 200.8 is in "Methods for the
Determination of Metals in Environmental Samples" (EPA 600/4-91/010).
Please delete SW-846 from the Table. Method 200.8 does not include
Mercury, Nickel, Selenium, Silver, Thallium, Tin, Vanadium, or Zinc.
Please list the appropriate methods for these analytes and revise the
table accordingly.

**Response to Comment No. 2:** The reference in Table 7-4 has been
corrected as indicated in the comment. Enclosed with this letter as
Attachment 1 are copies of the first two pages of Method 200.8, Revision
5.4 published by the EPA Environmental Monitoring Systems Laboratory in
Cincinnati, Ohio. Page 200.8-2 states that Method 200.8 is applicable
for the determination of Mercury, Nickel, Selenium, Silver, Thallium,
Tin, Vanadium, and Zinc in ground waters and soils.

**Comment No. 3:** From URSGWC's response. Have the MDLs and RLs listed
in Tables 7-1 through 7-4 been provided by PSS? Since PSS may be
subcontracting some of the analyses out, are these MDLs and RLs that PSS
expects Pace to meet or are these MDLs that Pace provided. The Tables
shoild clarify where MDLs and RLs have come from. Also, footnote 1 needs
to be moved to RLs as currently it is footnoting the MDL and in
actuality it refers to RLs. As stated under the review of Pace's LQAP,
no RLs or MDLs were provided in Pace's LQAP. If some of the MDLs and RLs
have been provided from Pace and it is clearly designated on the Tables,
then issue of the RLs and MDLs no being in Pace's LQAP becomes obsolete.

**Response to Comment No. 3:** Please refer to our "Response to Comment
No. 1", above, regarding MDLs and PQLs. The footnote in Tables 7-1
through 7-4 has been corrected as indicated in the comment.

**Comment No. 4:** It is not clear what is meant by URSGWC's response.
Tables 7-1 through 7-4 have been revised and there are still outstanding
issues with those tables (see comment earlier in this letter). The
original comment was a deficiency found in PSS's LQAP. If PSS provoded
MDLs and RLs (those listed in Tables 7-1 through 7-4), then this part of
the deficiency has been addressed. The LQAP still needs to included
extraction, digestion, and method numbers.

**Response to Comment No. 4:** Please refer to our "Response to Comment
No. 1" and "Response to Comment No. 2", above.

**Comment No. 5:** This information was not included in revision 1 in
PSS's LQAP. This deficiency still remains.

**Response to Comment No. 5:** The original comment concerned
calibration procedures for laboratory equipment. Those procedures are
included in PSS's Quality Assurance Plan (QAP). Pace, as a subcontractor
to PSS, will follow those procedures specific to calibration of
laboratory contained in PSS's QAP.

**Comment No.6:** This information was not included in revision 1 in
PSS's LQAP. This deficiency still remains.

**Response to Comment No. 6:** The original comment concerned
performance system audits, proficiency testing, inter-laboratory
comparisons, and providing copies of laboratory certifications. This
information is included in the revised QAPs for PSS (Appendix A of the
QAPP) and Pace (Appendix B of the QAPP).

**Comment No.7:** This information was not included in revision 1 in
PSS's LQAP. This deficiency still remains.

**Response to Comment No. 7:** The original comment concerned the
demonstration of acceptability of laboratory hardware and software, and
detection of potential laboratory fraud. The primary way these issues
will be reviewed is through URS's evaluation and validation of
laboratory generated data and the submittal of duplicate field samples.
Also, URS will obtain and review results of each laboratory' performance
audits conducted by State and Federal agencies, as they become
available.

**[NOVEMBER 22, 2000 COMMENTS ON RESPONSE TO COMMENTS: DCQAP PART 1: FSP
AND PART 2: QAPP, DMP -- REVISION 1, AND DCC & IM/SS -- REVISION
2]{.underline}**

**Note to reader:** All comments presented in the November 22, 2000
letter as "Response Satisfactory" are not included in the following list
of comments. No further action was required for those comments.

**Original Comments - EPA March 7, 2000 Letter**

> **[General Comment(s): RCRA Facility Investigation Work
> Plan]{.underline}**
>
> **Comment No. G1:** See EPA Letter dated August 10, 2000
>
> **Response to Comment No. G1:** Please refer to our responses under
> the heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}
>
> **Comment No. G2:** See EPA Letter dated August 10, 2000
>
> **Response to Comment No. G2:** Please refer to our responses under
> the heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}
>
> **[Specific Comments: DCQAP -- FSP]{.underline}**
>
> **Comment No. 1:** See EPA Letter dated August 10, 2000
>
> **Response to Comment No. 1:** Please refer to our responses under the
> heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}
>
> ***Sample Handling and Custody Requirements***
>
> **Comment No. 2:** See EPA Letter dated August 10, 2000
>
> **Response to Comment No. 2:** Please refer to our responses under the
> heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}
>
> ***Quality Control Requirements***
>
> **Comment No. 3:** See EPA Letter dated August 10, 2000
>
> **Response to Comment No. 3:** Please refer to our responses under the
> heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}
>
> **Comment No. 4:** See EPA Letter dated August 10, 2000
>
> **Response to Comment No. 4:** Please refer to our responses under the
> heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}

**Original Comments - EPA March 13, 2000 Letter**

> **[General Comment: DCQAP - QAPP]{.underline}**
>
> **Comment No. 1:** Appendix A -- See EPA Letter Dated August 10, 2000
> for deficiencies in LQAP.
>
> **Response to Comment No. 1:** Please refer to our responses under the
> heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}
>
> **[Specific Comments - DMP]{.underline}**
>
> **Comment No. 4:** Be advised that errors have been found in Excel's
> handling of some statistical functions. See ***On the accuracy of
> statistical procedures in Microsoft Excel 97***, B.D. McCullough,
> [Computational Statistics & Data Analysis]{.underline}, August 13,
> 1999.
>
> **Response to Comment No. 4:** The comment is noted. The most current
> version of EXCEL^TM^ available at the time the statistical analysis is
> performed shall be used.
>
> **[Specific Comments - FSP]{.underline}**
>
> **Comment No. 10:** Response Satisfactory; altered text may need
> revision pending review of response to comment 11, below \[3/22/00\]
>
> **Response to Comment No. 10:** The second bulleted item in Section
> 3.8.2 of the FSP-Revision 2 was revised as follows: "Each well will be
> purged prior to sampling so that collected samples are representative
> of aquifer conditions. Wells will be purged using a "low-flow"
> variable speed submersible pump. Purging will be considered complete
> when values of pH, temperature, turbidity, and specific conductance
> are within 10% for three consecutive readings. Water quality testing
> procedures shall be conducted in accordance with Standard Operating
> Procedure (SOP) \[C2\] Water Quality Monitoring Equipment." Also, SOP
> \[G3\] Ground water Sampling from Monitoring Wells has been revised to
> reflect this change in purging and sampling techniques.
>
> **Comment No. 11:** The measurement of turbidity is integral to
> determining stabilization during low flow purging techniques. Insuring
> that the lowest possible levels of particles are present in monitoring
> well samples will minimize artificial results, especially for metals.
> Use of a turbidity meter for determining whether steady state
> conditions have been reached as part of low flow techniques is
> advisable. We recommend that turbidity measurements be taken and three
> consecutive results within +/- 10% be measured prior to sampling the
> well.
>
> **Response to Comment No. 11:** Please refer to our "Response to
> Comment No. 10" above under [Specific Comments -- FSP]{.underline}.

**Original Comments -- EPA March 22, 2000 Letter**

> **[General Comment: DCC & IM/SS]{.underline}**
>
> **Comment No. 4:** Groundwater sample results should be screened using
> the lower of the MCLs or the tap water RBCs.
>
> **Response to Comment No. 4:** For the purposes of describing known
> groundwater conditions at the site, historic groundwater data were
> compared to tap water RBCs to facilitate in identifying data gaps and
> placing new groundwater monitoring wells to be installed under the
> RFI. Data derived from the sampling of existing and new wells under
> the RFI shall be compared to the lower of either the tap water RBC or
> MCL. Since comparing historic data to tap water RBCs is already a
> conservative approach and new data on groundwater contaminant
> concentrations will be derived and assessed during the RFI, comparing
> the previous data (historic) data to MCLs was deemed unnecessary.
>
> **Comment No. 9:** Response Satisfactory; distances should be provided
> to EPA prior to installation. \[3/22/00\]
>
> **Response to Comment No. 9:** The original comment referred to
> distances between the location of a well that is abandoned because it
> is no longer functional and its replacement well. The distances
> between a well to be abandoned and its replacement will be included in
> the request to EPA for approval of the location and depth of
> replacement wells. This request for approval will be made prior to
> beginning the installation of any replacement wells.
>
> **Comment No. 10:** Response Satisfactory, altered text may need
> revision pending review of response to comment 11. \[3/22/00\]
>
> **Note to reader: The response to comment 11 was accepted by EPA and
> no additional comment was issued.**
>
> **Response to Comment No. 10:** The original comment referred to the
> type of pump to be used to purge water from monitoring wells. Comment
> 11 referred to the measurement of turbidity as one indicator parameter
> of adequate well purging. Turbidity will be measured during well
> purging and will be used as one indicator parameter (refer to our
> Response to Comment No. 11 above under [Specific Comments --
> FSP]{.underline}.
>
> **[Specific Comments: DCC & IM/SS]{.underline}**
>
> **Comment No. 16:** The last paragraph of the response describes the
> addition of a statement addressing the preparation of a risk
> assessment, etc. However, it does not appear that the sentence was
> added to revision 2 of the DCC.
>
> **Response to Comment No. 16:** Page 4-1 of Revision 2 of the DCC &
> IM/SS was inadvertently printed twice (double-sided) and page 4-2 that
> included the revision described in the comment response was not
> issued. The enclosed DCC & IM/SS includes the missing page 4-2.
>
> **Comment No. 18:** See Specific Comment 10.
>
> **Response to Comment No. 18:** Please refer to "Response to Comment
> No. 10" above under the heading: [General Comment: DCC &
> IM/SS]{.underline}.
>
> **[Newly Included Figures: DCC & IM/SS]{.underline}**
>
> **Comment No. 21:** The issue of evaluation and remediation of Bldg
> 118, owned and operated by U.S. Navy, is still outstanding: include in
> RFI Work Plan.
>
> **Response to Comment No. 21:** The following sentence has been added
> to the end of the paragraph in Section 3.2: "The GSA has copies of
> investigation and remediation reports of findings for these two
> buildings. All investigations and remedial actions are being conducted
> by the WNY. Results of all WNY-conducted investigations and remedial
> actions available at the time the SEFC RFI is completed will be
> included in the SEFC RFI risk assessment and RFI report."
>
> **Comment No. 23:** The soil sampling reports of excavation and
> closure of various blocks/areas and original investigatory data for
> the noted areas of concern were evaluated as part of EPA's review
> process. EPA expressed its concern for the use of modified screening
> concentrations, use of industrial screening concentrations, etc. for
> the criteria for soil remediation. However, the report indicated that
> several blocks/areas have been prematurely removed as areas of concern
> form the RFI process. Table 1, SUMMARY OF REVIEW COMMENTS, below,
> lists each area of concern along with GSA's recommendation for future
> action along with investigatory sample results (if data is included in
> the DCC). Based on EPA's review of available information, some areas
> of concern should be included in the RFI. As noted in table 1, other
> areas may need to be included following review of data that was not
> included in the DCC.
>
> **Response to Comment No. 23:** Presented below is a summary of the
> action recommended in Revision 2 of the DCC & IM/SS followed by EPA's
> comment for each particular area of concern. Only those areas of
> concern where the EPA was not in concurrence with the recommended
> action are included.
>
> **[Area Block B:]{.underline}** No further investigation recommended,
> EPA observed that PAHs and PCBs at sample location K&D08 exceeded RBCs
> -- The following paragraph was added to the end of Section 3.3.3: "A
> comparison of constituents detected to October 5, 2000 EPA residential
> soil RBCs indicates that concentrations of three SVOCs
> (Benzo(a)pyrene, Benzo(b)fluoroanthene, and Dibenzo(a,h)anthracene)
> and one PCB (Aroclor 1260) exceed respective RBCs at location K&D08.
> Additional investigation in the vicinity of K&D08 will be conducted
> under the RFI."
>
> **[Area F1:]{.underline}** Further investigation of the north end of
> Area F1was recommended, EPA recommended that the analyses include
> VOCs, SVOCs, and metals -- A soil boring completed as a groundwater
> monitoring well is proposed to be installed at the north end of Area
> F1 in Revision 2 of the FSP. Both soil and groundwater are proposed to
> be tested for VOCs, SVOCs, and metals. The following sentences were
> added to the end of Section 3.3.7: "As discussed with the EPA, risk
> assessments cannot be performed on TPH concentrations. Therefore, the
> COC will be VOCs, SVOCs, and metals."
>
> **[Area G1:]{.underline}** Further investigation of the bottom and
> north end of Area G1 was recommended, EPA recommended that in addition
> to analysis for PCBs, analysis for PAHs be conducted - The following
> sentence was added before the last sentence of Section 3.3.8 Area G1:
> "A comparison of the constituents detected to October 5, 2000 EPA
> residential soil RBCs indicates that in addition to PCBs, the
> concentrations of four SVOCs (Benzo(a)anthracene, Benzo(a)pyrene,
> Benzo(b)fluoroanthene, and Dibenzo(a,h)anthracene) exceed respective
> RBCs at location K&D25." In Revision 2 of the FSP, SVOCs are proposed
> in the analytical parameter list for samples in Area of Investigation
> G.
>
> **[Area G2:]{.underline}** Further investigation of the north end of
> Area G2 was recommended, EPA recommended that analysis for VOCs and
> SVOCs conducted -- In Revision 2 of the FSP, VOCs and SVOCs are
> proposed in the analytical parameter list for samples in Area of
> Investigation G. The following sentences were added to the end of
> Section 3.3.8 Area G2: "As discussed with the EPA, risk assessments
> cannot be performed on TPH concentrations. Therefore, the COC will be
> VOCs and SVOCs."
>
> **[Areas H1, H2, and H3:]{.underline}** Investigation of groundwater
> quality below Block H was proposed, EPA recommended that analysis of
> PAHs in soil be conducted -- In Section 2.8.6, the following statement
> is made regarding previous testing for SVOCs in soil within Block H:
> "PAH concentrations at reporting limits sufficient for the preparation
> of a risk assessment were not obtained due to high concentrations of
> TPH present in the soil." Therefore, testing for SVOCs in soil from
> Block H will likely yield similar results -- the petroleum hydrocarbon
> concentrations are at such a level that they cause the background
> level (baseline level) of the PAH analysis to be elevated to point
> that detection limits will be much greater than risk screening levels.
> Based on this assessment, inclusion of PAHs in the RFI sampling
> program for this block is not recommended.
>
> **[Areas J1, J3, J5, and J6:]{.underline}** Investigations of the
> remaining PCBs in soil at Area J1, metals in soil at Areas J3 and J6,
> and SVOCs in soil at Area J5 were recommended, EPA observed that PAHs
> were present at levels slightly above residential soil RBCs --
> Revision 1 of the FSP recommended the analysis of soil samples from
> all boreholes within Block J for metals, SVOCs, and PCBs. Revision 2
> of the FSP also recommends that soil samples collected from boreholes
> within Block J be analyzed for metals, PCBs, and SVOCs.
>
> **[Areas J2 and J4:]{.underline}** No further investigations at Areas
> J2 and J4 were recommended, EPA recommended that results of previous
> investigations be included in the RFI risk assessment -- All previous
> data pertaining to materials that still are present at the site will
> be included in the RFI risk assessment. Data pertaining to soils that
> have been removed under the voluntary soil remedial actions already
> conducted will not be included since that material is no longer on the
> site. However, soil excavation confirmatory sample data will be
> included in the RFI risk assessment. The following sentence has been
> added to the end of Section 3.3.10: "The confirmatory sample data will
> be included in the RFI risk assessment."
>
> **[Areas L1, M2, N1, N2, and N4:]{.underline}** No further
> investigations were recommended, EPA recommended that results of
> previous investigations be included in the RFI risk assessment -- All
> previous data pertaining to materials that still are present at the
> site will be included in the RFI risk assessment. Data pertaining to
> soils that have been removed under the voluntary soil remediations
> already conducted will not be included since that material is no
> longer on the site. However, soil excavation confirmatory sample data
> and excavation limit confirmatory sample data will be included in the
> RFI risk assessment. The following sentence has been added to the end
> of Sections 3.3.12, 3.3.13 Area M2, 3.3.14 Area N2, and 3.3.14 Area
> N4: "The confirmatory sample data will be included in the RFI risk
> assessment." The following sentence has been added to the end of
> Section 3.3.14 Area N1: "Laboratory data from these soil borings will
> be included in the RFI risk assessment."
>
> **[Area M1:]{.underline}** Further investigation of VOCs in Area M1
> was recommended, EPA recommended that additional constituents of
> concern be evaluated for possible inclusion into the analytical
> parameter schedule -- The soil and groundwater sample location
> MN-SB/MW08, proposed in Revision 1 and included in Revision 2 of the
> FSP, is immediately adjacent to this area. Samples from this
> investigation location are proposed to be analyzed for metals, VOCs,
> and SVOCs.
>
> **[Area N3:]{.underline}** Further investigation of SVOCs in Area N3
> was recommended, EPA recommended that additional constituents of
> concern be evaluated for possible inclusion into the analytical
> parameter schedule -- The soil and groundwater sample locations N-SB01
> and N-SB/MW02, proposed in Revision 2 of the FSP, are immediately
> north and south of this area. Samples from these investigation
> locations are proposed to be analyzed for metals and SVOCs. Also, the
> following sentence was added to the end of Section 3.3.14 Area N3:
> "The confirmatory sample results will be included in the RFI risk
> assessment."
>
> **[Area O1:]{.underline}** Further investigation of metals in Area O1
> was recommended, EPA observed that PAHs were present at levels above
> residential and commercial soil RBCs -- The last sentence in Section
> 3.3.15 Area O1 was revised as follows: "Further investigation and an
> evaluation of the risk posed by the remaining metals and SVOCs will be
> conducted as part of the RFI." Also, in Revision 2 of the FSP the
> analytical parameter SVOCs was added to the testing schedule for
> sample location O1-SB06, which is immediately adjacent and
> downgradient of the area.
>
> **[Area O2:]{.underline}** No further investigations were recommended,
> EPA recommended that results of previous investigations be included in
> the RFI risk assessment -- All previous data pertaining to materials
> that still are present at the site will be included in the RFI risk
> assessment. Data pertaining to soils that have been removed under the
> voluntary soil remediations already conducted will not be included
> since that material is no longer on the site. However, soil excavation
> confirmatory sample data will be included in the RFI risk assessment.
> The following sentence has been added to the end of Sections 3.3.15
> Area O2: "The confirmatory sample results will be included in the RFI
> risk assessment."
>
> **[Areas O3 and O4:]{.underline}** Further investigation of TPH was
> recommended, EPA recommended that an expanded COC list be considered
> -- As agreed to at the February 22, 2001 meeting, samples previously
> proposed to be tested for the analytical parameter "TPH" will now be
> tested for VOCs and SVOCs. Also, as proposed in Revision 2 of the FSP,
> soil from all investigation sample locations around Area O4
> (O2-SB/MW05, O2-SB/MW06, O2-SB02, and O2-SB03) will be tested for
> metals in addition to VOCs and SVOCs.
>
> **[Areas SF-1, SF2-1, SF2-2, and SF2-3:]{.underline}** Further
> investigation along the border between the remainder of Area SF
> (includes all four areas) and the area of soil removed will be
> conducted under the RFI to delineate any further metals contamination
> was recommended, EPA recommended analysis for PAHs be included -- The
> following sentence was added to the end of Section 3.3.16: "Also,
> since SVOCs were detected in Area SF soil samples above October 5,
> 2000 EPA residential soil RBCs, the investigation will include
> analysis and risk assessment of SVOCs." Also, as proposed in Revision
> 2 of the FSP, all investigation sample locations bordering Area SF
> (SF-SB/MW01, SF-SB/MW02, N-SB/MW02, N-SB/MW03, and O1-SB/MW10) will be
> tested for both metals and SVOCs.

**Original Comments -- EPA March 23, 2000 Letter**

**[QAPP]{.underline}**

> **Comment:** See EPA letter dated August 10, 2000
>
> **Response to Comment:** Please refer to our responses under the
> heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}
>
> **[QAPP -- Phase Separation Science, Inc. Laboratory
> QAP]{.underline}**
>
> **Comment:** See EPA letter dated August 10, 2000
>
> **Response to Comment:** Please refer to our responses under the
> heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}

**Original Comments -- EPA April 12, 2000 Letter**

> **[DCC & IM/SS]{.underline}**
>
> **Comment No. 1:** Section 3.3.1.1: The response that future data will
> be evaluated using current EPA risk assessment protocols and guidance
> is acceptable; however, it should be noted that revision 2 of the DCC
> and Interim Measures Report includes recommendations for no further
> action in the RFI for some areas of concern based on the screening
> process outlined in Section 3.3.1.1 and sometimes limited confirmation
> data. See March 22, 2000 response to comment No. 23, above.
>
> **Response to Comment No. 1:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 2:** Section 3.3.1.3: The response that future data will
> be evaluated using current EPA Risk-Based Concentrations is
> acceptable; however, recommendations for no further action were made
> based on use of refined action levels (noted in EPA comments as
> unacceptable) for some areas of concern. See March 22, 2000 Comment
> No. 23, above.
>
> **Response to Comment No. 2:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 3:** Section 3.3.1.4: See March 22, 2000 Comment No. 23,
> above.
>
> **Response to Comment No. 3:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 4:** Section 3.3.1.6 and 3.3.1.7: See March 22, 2000
> Comment No. 23, above.
>
> **Response to Comment No. 4:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 5:** Section 3.3.1.9: See March 22, 2000 Comment No. 23,
> above.
>
> **Response to Comment No. 5:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 6:** Section 3.3.2 through 3.3.16: The response is
> acceptable; however, as noted in cover letter, recommendations for no
> further action in the RFI were made for some areas of concern using
> limited or no confirmation data.
>
> **Response to Comment No. 6:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **[General Comments: FSP]{.underline}**
>
> **Comment No. 5:** See Attachment for parameters to be tested in
> soil/groundwater for petroleum releases.
>
> **Response to Comment No. 5:** As agreed to at the February 22, 2001
> meeting between the EPA, GSA, and URS, soil samples collected in areas
> of concern where petroleum compounds are of concern will be analyzed
> for Appendix IX Volatiles, Appendix IX Semivolatiles, and Methy
> tert-butyl ether. Groundwater samples, site-wide, will be analyzed for
> Appendix IX Volatiles, Appendix IX Semivolatiles, and Appendix IX
> Inorganics excluding Cyanide and Sulfide.
>
> **Comment No. 6:** See March 22, 2000 and April 12, 2000 toxicological
> comments, above.
>
> **Response to Comment No. 6:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **[Specific Comments: FSP]{.underline}**
>
> **Comment No. 15:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 15:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 22:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 22:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 24:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 24:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 26:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 26:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 29:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 29:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 33:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 33:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 34:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 34:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 35:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 35:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **Comment No. 36:** See March 22, 2000 and April 12, 2000
> toxicological comments, above.
>
> **Response to Comment No. 36:** Please refer to our "Response to
> Comment No. 23" above under the heading: [Newly Included Figures: DCC
> & IM/SS]{.underline}.
>
> **[New Comments: FSP]{.underline}**
>
> **Comment No. 1:** No new information were added to Table 3-10 for
> MW-1 thru MW-8. Revisit this issue during the RFI.
>
> **Response to Comment No. 1:** As stated in the FSP, the elevations of
> the top of ground surface will be measured for these and all
> monitoring wells during the RFI so groundwater surface elevations can
> be calculated.
>
> **Comment No. 2:** The detection limits in Table 3-14 for HP-1, 3, 4,
> 6 are too high and may render data non-usable. Revisited during RFI.
>
> **Response to Comment No. 2:** The table lists historic analytical
> results of groundwater samples collected using Hydropunch^TM^ and well
> point methods. These data will not be used in the RFI risk assessment
> as they are considered "screening" data. Groundwater sample analyses
> conducted will be reported at the detection limits listed in the QAPP,
> unless dilutions are necessary to report concentrations that are out
> of the low-level calibration range of the instrument.
>
> **Comment No. 3:** Info. regarding SF-1, SF2-1, SF2-2, SF2-3, N-1,
> N-4, A-1, K-1 and L-1 have been attached as Appendix I in Revision 2.
> All data for use in the risk assessment must be validated in
> accordance with EPA guidelines. Revisit these areas for groundwater
> consideration during RFI.
>
> **Response to Comment No. 3:** Appendix I of the DCC & IM/SS includes
> analytical results for soil samples collected from the sides and
> bottoms of excavations. The excavations were conducted as a voluntary
> action to remove known areas of impacted soils from the site.
> Groundwater samples are proposed to be collected from these soil
> excavation areas (including those listed in the comment). As stated in
> the DMP, all data used in the RFI risk assessment will have been
> validated.
>
> **Comment No. 4:** The Issue of evaluation and remediation of Bldg.
> 118, owned and operated by US Navy is still outstanding; include in
> RFI Work Plan.
>
> **Response to Comment No. 4:** Please refer to our "Response to
> Comment No. 21" under the sub-heading: Original Comments -- EPA March
> 22, 2000 Letter, [Newly Included Figures: DCC & IM/SS.]{.underline}
>
> **Comment No. 5:** Confirmatory soil sampling results (primarily PCB)
> for Buildings 160, 167, 170 and 173 have been added to revision 2 in
> page 3-7 through 3-10. See Item #3.
>
> **Response to Comment No. 5:** Since concentrations of PCBs in soil
> below 1 part-per-million were reached in each voluntary removal action
> mentioned above, and these levels were achieved at elevations above
> the groundwater surface, no sampling and analysis of groundwater for
> PCB content is planned under the RFI.
>
> **Comment No. 6:** Provide the rationale for soil removal level of
> 5,000 mg for lead; confirmatory sampling results above EPA levels are
> not acceptable for exclusion of an Area/Block from the RFI Work Plan.
> See Item #3, above.
>
> **Response to Comment No. 6:** Soil excavation areas where lead was a
> constituent of concern have not been removed from consideration in the
> RFI. All soil excavations where lead was a concern were designed based
> on removing lead contaminated soil above 400 mg/kg, not 5,000 mg/kg.
> Further investigation and/or an evaluation of the increased risk posed
> by the concentrations of lead remaining in the soil at these
> excavation areas will be conducted under the RFI.
>
> **[QAPP]{.underline}**
>
> **Comment No. G2:** See EPA letter dated August 10, 2000
>
> **Response to Comment No. G2:** Please refer to our responses under
> the heading: [August 10, 2000 Comments on Responses to Comments: DCQAP
> Part 2: QAPP -- Revision 1.]{.underline}

In addition to the above described revisions, our review of the
documents revealed that revisions were needed to make them suitable as
another submission to EPA. These revisions include the following:

-   Changing the title page and text page headers of the DCC & IM/SS and
    CRP to read "Final" , and changing the title page and text headers
    of the DCQAP, DMP, HSP, and PMP to read "Revision 2",

-   Changing the submission dates to April 16, 2001, the next scheduled
    submission date to EPA,

-   Changing our company name to URS Group, Inc. on the cover pages and
    throughout the documents,

-   Changing sentences describing building abatement activities to the
    past-tense and changing the dates of completion,

-   Revising the bulleted portion of Section Four in the DCC & IM/SS,
    Section 1.3.3 of the CRP and DMP, Section 3.3 of the HSP, Section
    1.3.3 of the QAPP, and Section 1.4.3 of the PMP to reflect changes
    to the FSP approved by the EPA and additional investigations to be
    conducted for the previously undocumented buildings and areas
    described in our February 13, 2001 report,

-   Revising Section 2.2 Sampling Locations, and Table 2-1 sampling and
    Analysis requirements, of the FSP to reflect additional
    investigations required by our responses to comments concerning
    excavation areas described in the DCC & IM/SS and investigations of
    previously undocumented buildings and areas described in our
    February 13, 2001 report.

-   Adding the following paragraph to the Executive Summary of the DCC &
    IM/SS: "In Section Three of this report, constituent concentrations
    remaining in soil were compared to EPA Risk-Based Concentrations
    (RBCs) for residential soil scenarios published at the time this
    document was prepared (RBCs, October 5, 2000). This comparison was
    conducted in order to evaluate whether previously investigated areas
    required further study. It is recognized that RBCs are updated
    approximately every 6 months. RBCs published once the RCRA Facility
    Investigation (RFI) for the property is completed will be used at
    that time to evaluate the increased risk posed by the constituents
    remaining in the site soils."

-   Correcting spelling, punctuation, and grammatical mistakes.

-   At the request of EPA Region III, changing the phrase "public
    repositories" to "public information facilities" in the CRP and DMP,

-   Updating the reference to the DCC & IM/SS in all RFI Workplan
    Documents,

-   Adding our February 13, 2001 report concerning the previously
    undocumented buildings and areas to the reference section of all RFI
    Workplan Documents,

-   Updating Section 3.2 of the DMP (AOI Identification Codes) to
    reflect changes to the FSP,

-   Adding to Section Five of the DMP a statement that ground water
    surface contour maps will be generated based on an EPA approved
    comment response concerning the DCC & IM/SS,

-   Updating Section Two of the HSP and Figure 5-2 of the PMP (Project
    Organization) to reflect URS employee changes (certain employees
    leaving and new staff joining URS), and

-   Deleting references to Hydropunch^TM^ and Geopgobe^TM^ sampling from
    Section Four of the HSP (Work Activities) since these techniques
    will not be utilized.

If you have any questions, please do not hesitate to contact Chris
Gerber at (301) 670-3310 or Kevin Dill at (301) 670-3359.

Sincerely,

Chris Gerber, P.G. Kevin Dill, P.E.

URS RCRA 3013 Project Manager Program Manager

Enclosure: DCC & IM/SS -- Final (proposed)

CRP -- Final (proposed)

DCQAP, DMP, HSP, PMP -- Revision 2

CDG:als