United States Environmental Protection 1200 Pennsylvania Avenue, N.W. Agency Washington, D.C. 20460 0 D\ 2013 Office of Solid Waste and Emergency Response


# Support Document for the Revised National Priorities List Final Rule – Macon Naval Ordnance Plant

# Support Document for the Revised National Priorities List Final Rule Macon Naval Ordnance Plant May 2013

Site Assessment and Reme dy Decisions Branch Office of Superfund Remediati on and Technology Innovation Office of Solid Waste and Emergency Response U.S. Environmental Protection Agency Washington, DC 20460

iMacon Naval Ordnance Plant NPL Listing Support Document May 2013



## Table of Contents

Executive Summary

.............................................................................................................................. ..... iv

Introduction

.............................................................................................................................. .................. iv
Background of the NPL

........................................................................................................................... iv Development of the NPL

......................................................................................................................... iv Hazard Ranking System

........................................................................................................................... v Other Mechanisms for Listing

................................................................................................................. vi Organization of this Document ................................................................................................................ vi Glossary

.............................................................................................................................. .................... vii
1. List of Commenters and Correspondence ........................................................................................ 1

2. Site Description

.............................................................................................................................. ..... 1

3. Summary of Comments ..................................................................................................................... 2

3.1 Support for Listing and Other Non-opposition Comments ........................................................... 5
3.2 Consistency with HRS

.................................................................................................................. 5 3.2.1 Consistency with Guidance

................................................................................................................. 6
3.3 Site Name

.............................................................................................................................. ....... 7
3.4 Liability

.............................................................................................................................. .......... 7
3.5 Criteria for Listing

........................................................................................................................ 8
3.6 Data Quality Issues

....................................................................................................................... 8
3.7 Data Selection - Use of Previous Sampling Data

.......................................................................... 9
3.8 Site Definition

............................................................................................................................. 10
3.9 Source 1

.............................................................................................................................. ........ 11 3.9.1 Representativeness of the Background Sample

................................................................................. 13 3.9.2 Using Qualified Analytical Data that Impact th e Quantification of Mercury in the Source Sample . 15 3.9.3 Documenting Mercury Contamination in the Source Sample ........................................................... 17
3.10 Observed Release – Background

................................................................................................ 18 3.10.1 Adequacy of Background Sa mple - Observed Release

..................................................................... 20 3.10.2 Sample Similarity

.............................................................................................................................. 21 3.10.3 Number of Background Samples Used to Identify an Observed Release .......................................... 22
3.11 Observed Release - Attribution

................................................................................................... 23 3.11.1 Possible Mercury Releases from Alternative Sites

............................................................................ 25 3.11.1.1 Wastewater Discharges from GP and the So uthern Wood Piedmont Company via the RCWRF 27 3.11.1.2 GP Air Emissions

......................................................................................................................... 29 3.11.1.3 Contribution of Sources West and North of Source 1

................................................................... 30 3.11.2 Contaminant Concentration Gradient in Drainage Ditch #4 .............................................................. 30 3.11.3 Contaminant Concentration Downgradient of the RCWRF

.............................................................. 32 3.11.4 Other Data Sets

.............................................................................................................................. ... 34
3.12 Characterization of PPE 1 ........................................................................................................... 36

iiMacon Naval Ordnance Plant NPL Listing Support Document May 2013

iii 4. Conclusion

.............................................................................................................................. ........... 37

Attachment 1: Macon Water Authority, Rocky C reek Effluent Sample Results, Various Dates
Attachment 2: Macon Water Authority, Rocky Creek Biosolids Mercury Data, Undated
Attachment 3: Macon Water Authority, Status of MWA lines to Ocmulgee River from Rocky Creek POTW, January 24, 2003Macon Naval Ordnance Plant NPL Listing Support Document May 2013



## Executive Summary

Section 105(a)(8)(B) of CERCLA, as amended by SARA, requires that the EPA prepare a list of national priorities among the known releases or threatened re leases of hazardous substances, pollutants, or contaminants throughout the United States. An origin al National Priorities List (NPL) was promulgated on September 8, 1983 (48 FR 40658). CERCLA requires that the EPA update the list at least annually.
This document provides responses to public comme nts received on the Macon Naval Ordnance Plant, proposed on March 15, 2012 (77 FR 15344). This site is being added to the NPL based on an evaluation under the EPA’s Hazard Ranking System (HRS ) in a final rule published in the Federal Register in May 2013.

ivMacon Naval Ordnance Plant NPL Listing Support Document May 2013



## Introduction

This document explains the rationale for adding the Macon Naval Ordnance Plan t site in Macon, Georgia, to the National Priorities List (NPL) of uncontrolled hazardous waste sites and also provides the responses to public comments received on this site. The EPA proposed this site on March 15, 2012 (77 FR 15344). This site is being added to the NPL based on an evaluation under the Hazard Ranking System (HRS) in a final rule published in the Federal Register in May 2013. 

### Background of the NPL
In 1980, Congress enacted the Comprehensive Enviro nmental Response, Compensation, and Liability Act (CERCLA), 42 U.S.C. Sections 9601 et seq . in response to the dangers of uncontrolled hazardous waste sites. CERCLA was amended on October 17, 1986, by the Supe rfund Amendments and Reauthorization Act (SARA), Public Law No. 99-499, stat., 1613 et seq. To implement CERCLA, the EPA promulgated the revised National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 CFR Part 300, on July 16, 1982 (47 FR 31180), pursuant to CERCLA Section 105 and Executiv e Order 12316 (46 FR 42237, August 20, 1981). The NCP, further revised by the EPA on September 16, 1985 (50 FR 37624) and November 20, 1985 (50 FR 47912), sets forth guidelines and procedures needed to respond under CERCLA to releases and threatened releases of hazardous substances, pollutants, or contaminants. On Ma rch 8, 1990 (55 FR 8666), th e EPA further revised the NCP in response to SARA.
Section 105(a)(8)(A) of CERCLA, as amended by SARA, requires that the NCP include
criteria for determining priorities among releases or threatened releases throughout the United States for the purpose of taking remedial action and, to the extent practicable, take into account the potential urgency of such action, for the purpose of taking removal action.
Removal action involves cleanup or other actions that ar e taken in response to emergency conditions or on a short-term or temporary basis (CERCLA Section 101). Re medial action is generally long-term in nature and involves response actions that are consistent with a permanent remedy for a release (CERCLA Section 101). Criteria for placing sites on the NPL, which makes them elig ible for remedial actions financed by the Trust Fund established under CERCLA, were included in the HRS. The EPA promulgated the HRS as Appendix A of the NCP (47 FR 31219, July 16, 1982). On December 14, 199 0 (56 FR 51532), the EPA promulgated revisions to the HRS in response to SARA, and established the effect ive date for the HRS revisions as March 15, 1991.
Section 105(a)(8)(B) of CERCLA, as amended, requires that the statutory criteria provided by the HRS be used to prepare a list of national priorities among the known rel eases or threatened releases of hazardous substances, pollutants, or contaminants throughout the United States. Th e list, which is Appendix B of the NCP, is the NPL.
An original NPL of 406 sites was promulgated on Septem ber 8, 1983 (48 FR 40658). At that time, an HRS score of 28.50 was established as the cutoff for listing because it yielded an initial NPL of at least 400 sites, as suggested by CERCLA. The NPL has been expanded several times since then, most recently on September 18, 2012 (77 FR 57546). The Agency also has published a numbe r of proposed rulemakings to add sites to the NPL. The most recent proposal was on September 18, 2012 (77 FR 57546). 

### Development of the NPL
The primary purpose of the NPL is stat ed in the legi slative history of CERCLA (Report of the Committ ee on Environment and Public Works, Senate Repor t No. 96-848, 96th Cong., 2d Sess. 60 [1980]).

ivMacon Naval Ordnance Plant NPL Listing Support Document May 2013

The priority list serves primarily informational purposes, identifying for the States and the public those facilities and sites or other releases which app ear to warrant remedial actions. Inclusion of a facility or site on the list does not in itself reflect a judgment of the activities of its owner or operator, it does not require those persons to un dertake any action, nor does it assign liability to any person. Subsequent government actions will be necessary in order to do so, and these actions will be attended by all appropr iate procedural safeguards.
The NPL, therefore, is primarily an informational and mana gement tool. The identification of a site for the NPL is intended primarily to guide the EPA in determining which sites warrant further investigation to assess the nature and extent of the human health and environmental risks associated with the site and to determine what CERCLAfinanced remedial action(s), if any, may be appropriate. The NPL also serves to notify the public of sites the EPA believes warrant further investigation. Finally, listing a site may, to the extent potentially responsible parties are identifiable at the time of listing, serve as notice to su ch parties that the Agency may initiate CERCLA-financed remedial action.
CERCLA Section 105(a)(8)(B) directs the EPA to list pr iority sites among the known releases or threatened release of hazardous substances, pollutants, or cont aminants, and Section 105(a)(8)(A) directs the EPA to consider certain enumerated and othe r appropriate factors in doing so. Thus, as a matter of policy, the EPA has the discretion not to use CERCLA to respond to certain types of releases. Where other authorities exist, placing sites on the NPL for possible remedial action under CERCL A may not be appropriate. Therefore, the EPA has chosen not to place certain types of sites on the NPL even though CERCLA does not exclude such action. If, however, the Agency later determines that sites not liste d as a matter of policy are not being properly responded to, the Agency may consider placing them on the NPL. 

### Hazard Ranking System
The HRS is the principle mechanism the EPA uses to place uncontrolled waste sites on the NPL. It is a numerically based screening system that uses information from initial, limited investigations -- the preliminary assessment and site inspection -- to assess the relative potentia l of sites to pose a threat to human health or the environment. HRS scores, however, do not determine th e sequence in which the EPA funds remedial response actions, because the information collected to develop HRS sco res is not sufficient in itself to determine either the extent of contamination or the appropriate response for a particular site. Moreover, the sites with the highest scores do not necessarily come to the Agency's attention first, so that addressing sites strictly on the basis of ranking would in some cases require stopping work at s ites where it was already underway. Thus, the EPA relies on further, more detailed studies in the remedial inves tigation/feasibility study that typically follows listing.
The HRS uses a structured value analysis approach to scoring sites. This approach assigns numerical values to factors that relate to or indicate risk, based on conditions at the site. The factors are grouped into three categories. Each category has a maximum value. The categories are:

• likelihood that a site has released or has the potential to release hazardous substances into the environment;

• characteristics of the waste (toxicity and waste quantity); and

• people or sensitive environments (targets) affected by the release.
Under the HRS, four pathways can be scored for one or more threats as identified below:

vMacon Naval Ordnance Plant NPL Listing Support Document May 2013

• Ground Water Migration (S gw ) - drinking water

• Surface Water Migration (S sw ) The following threats are evaluated for two separate migration components, overland/flood migration and ground water to surface water. - drinking water - human food chain - sensitive environments

• Soil Exposure (S s ) - resident population - nearby population - sensitive environments

• Air Migration (S a ) - population - sensitive environments
After scores are calculated for one or more pathways acco rding to prescribed guidelines, they are combined using the following root-mean-square equation to determine the overall site score (S), which ranges from 0 to 100 :



### 4 S + S + S + S = S 2

a 2

s 2

sw 2 gw

If all pathway scores are low, the HRS score is low. Howe ver, the HRS score can be relatively high even if only one pathway score is high. This is an important requirement for HRS scoring because some extremely dangerous sites pose threats through only one pathway. For exampl e, buried leaking drums of hazardous substances can contaminate drinking water wells, but -- if the drums ar e buried deep enough and the substances not very volatile -- not surface water or air. 

### Other Mechanisms for Listing
There are two mechanisms other than the HRS by whic h sites can be placed on the NPL. The first of these mechanisms, authorized by the NCP at 40 CFR 300.425(c)(2 ), allows each State and Territory to designate one site as its highest priority regardless of score. Th e last mechanism, authorized by the NCP at 40 CFR 300.425(c)(3), allows listing a site if it meets the following three requirements:

• Agency for Toxic Substances and Dis ease R egistry (ATSDR) o f the U.S. P ublic Health Service ha s issued a health advisory that recommends di ssociation of individuals from the release;

• EPA determines the site poses a significant threat to public health; and

• EPA anticipates it will be m ore cost-effective to us e its remedial authorit y than to use it s emergency removal authority to respond to the site. 

### Organization of this Document
The following section contains the EPA responses to site-specific public comments received on the proposal of the Macon Naval Ordnance Plant site on March 15, 2012 ( 77 FR 15344). The site discussion begins with a list of

viMacon Naval Ordnance Plant NPL Listing Support Document May 2013

commenters, followed by a site description, a summary of comments, and Agency responses to each comment. A concluding statement indicates the effect of the comments on the HRS score for the site. 

### Glossary
The following acronyms and abbreviations are used throughout the text:
Agency U.S. Environmental Protection Agency
AIP Allied Industrial Park
APA Administrative Procedure Act
AWI Armstrong World Industries
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act of 1980, 42 U.S.C. Sections 9601 et seq ., also known as Superfund
CFR Code of Federal Regulations
D.C. Cir U.S. Court of Appeals for the District of Columbia Circuit
DoD Department of Defense
EPA U.S. Environmental Protection Agency, also USEPA
FMNOL Former Macon Naval Ordnance Landfill
FR Federal Register
GP Graphic Packaging
HRS Hazard Ranking System, Appendix A of the NCP
HRS score Overall site score calculated using the Hazard Ranking System; ranges from 0 to 100
MCL Maximum contaminant level
μ g/kg Micrograms per kilogram
μ g/L Micrograms per liter
MNOP Macon Naval Ordnance Plant
MWA Macon Water Authority
NCP National Oil and Hazardous Substances Pollutio n Contingency Plan, 40 C.F.R. Part 300
NPDES National Pollution Discharge Elimination System
NPL National Priorities List, Appendix B of the NCP
NWI National Wetlands Inventory
OR Observed release
OSWER USEPA’s Office of Solid Waste and Emergency Response
PA Preliminary assessment
PCE Tetrachloroethene or tetrachloroethylene
PRP Potentially responsible party
PSA Pre-CERCLIS screening assessment

viiMacon Naval Ordnance Plant NPL Listing Support Document May 2013

viii QAPP Quality assurance project plan QA/QC Quality assurance/quality control
RCRA Resource Conservation and Recovery Act
RCWRF Rocky Creek Water Reclamation Facility
RI Remedial investigation
ROD Record of decision
SARA Superfund Amendments and Reauthorization Act
SCDM Superfund Chemical Data Matrix
SESD Science and Ecosystem Support Division
SI Site inspection
SWPC Southern Wood Piedmont Company
TCE Trichloroethene or trichloroethylene
USACE United States Army Corps of Engineers
USGS United States Geological Survey
VOC Volatile organic compoundMacon Naval Ordnance Plant NPL Listing Support Document May 2013



## 1. List of Commenters and Correspondence

EPA-HQ-SFUND-2012-0064-0004 State Concurrence Letter – Macon Naval Ordnance Plant submitted by F. Allen Barnes, Director, Georgia Department of Natural Resources
EPA-HQ-SFUND-2012-0064-0005 Comment and attachment submitted by Peter J. Fontaine of Cozen O’Conner
EPA-HQ-SF UND-2012-0064-0006 Comment and attachment submitted by Maureen EPA-HQ-SFUND-2012-0064-0008 Sullivan, Director, Environmental Management, on behalf of the Department of Defense (DoD)
EPA-HQ-SFUND-2012-0064-0007 Comment and attachment submitted by Peter J. Fontaine of Cozen O’Conner on behalf of Unimax Corporation
EPA-HQ-SFUND-2012-0064-0009 Comment and attach ment submitted by Michael W. Steinberg, Counsel, Morgan, Lewis & Bockius LLP
EPA-HQ-SFUND-2012-0071-0005 Comment and att achment submitted by Emily Hinchman, Rutgers University School of Law – Camden



## 2. Site Description

The Macon Naval Ordnance Plant (MNOP) site (the Site), lo cated in Macon, Georgia, is composed of the release of mercury from the former MNOP facility to Drainage Ditch #4 and into Rocky Creek. Land uses at the facility are predominantly commercial and heavy industrial. Th e MNOP facility was constructed and operated by the Reynolds Corporation befo re World War II for production of ordnance. In 1941, the U.S. Navy assumed operation of the plant and continued to manufacture or dnance there until 1965. Ordnance manufactured at the MNOP included flares, small primers, detonators, and other triggering mechanisms. Several industrial businesses such as Maxson Electronics Corporation, Allied Chem ical Corporation, and Macon-Bibb County Industrial Authority have owned and operated at the location of the MNOP facility since the Department of Defense (DoD) operations ceased in 1965.
The MNOP facility property is bordered to the north by Guy Paine Road; to the east by Mead Road and the Norfolk Southern railroad tracks; to the southeast by Graphic Packaging; to the south by the Macon Water Authority (MWA) Rocky Creek Water Reclamation Facility (RCWRF), the Armstrong World Industries (AWI) remote landfill, the former Macon Naval Ordnance Landfill (FMNOL), and Rocky Creek; and to the west by the AWI plant property (see Figure 1).
The Site for HRS scoring purposes includes one source (Source 1) -- contaminated soil on the eastern section of the MNOP property near Building 109, and the associated releases from the Site to dr ainage ditch #4. Source 1 consists of contaminated soil surrounding Building 109 which was a primary explosives production area. Soil samples collected from this area duri ng the U.S. Army Corps of Engineer’s (USACE) 1996 site investigation contained mercury. Mercury has also been detected at significant levels in sediments collected in wetlands that receive runoff from Source 1 via Drainage Ditch #4 on the east side of the facility, indicating that a release has occurred to the surface water migration pathway. The HRS Site score is based on the release of mercury to the surface water migration pathway and the resulting risk to nearby wetlands and a human food chain fishery.

1Macon Naval Ordnance Plant NPL Listing Support Document May 2013

2 Several investigations have been c onducted at MNOP between 1989 and 2011. Mercury has been associated with the MNOP site. The most recent investigation was a J une 2011 Supplemental Sampling Event (shown in Figure 1 below) and while all available data was used in the site evaluation and included as references to the HRS documentation record at proposal, the June 2011 data w as the basis for the HRS evaluation as it is the most current data and is focused on contamination in Drainage Ditch #4. Source background samples were taken on the northern portion of the MNOP property (MNOP-01-SF shown in Figure 1 below) and an observed release background level was based on a sample taken from southwest of the MNOP property located in the same wetland as the observed release sample (MNOP-W-01-SD s hown on Figure 3 of the HRS documentation record at proposal).



## 3. Summary of Comments

Two commenters, Michael W. Steinberg, on behalf of Counsel, Morgan, Lewis and Bockius LLP, and Emily Hinchman, from Rutgers University School of Law, each submitted a comment regarding all sites proposed for listing in March 2012, which include the former Macon Naval Ordnance Pl ant. These comments applicable to multiple sites are addressed in the pr eamble of the first Final Rule promulgating sites that were proposed for listing in March 2012 (77 FR 57498-57500, September 18, 2012).
The Director of the Georgia Department of Natural R esources, F. Allen Barnes, supported the placement of the former Macon Naval Ordnance Site on the National Priorities List (NPL) and commented that the listing will help compel responsible parties to plan remedi al action that is needed at the Site.
Three commenters submitted comments in opposition to placing the former Macon Naval Ordnance Plant on the NPL. Peter J. Fontaine of Cozen O’Conner (Cozen) s ubmitted a set of preliminary comments and later submitted additional comments on behalf of the Unimax Cor poration (Unimax). Maureen Sullivan, Director of Environmental Management, submitted comments on behalf of DoD. Cozen, Unimax, and DoD raised both site eligibility policy and technical HRS scoring issues.
Unimax commented that the EPA did not correctly follo w the HRS or HRS guidance in placing the Site on the NPL. Unimax also commented that the data used in the HRS documentation record was not of known and documented quality, was from unreliable previous sampling events, and used qualified data that should not be used in an HRS evaluation.

DoD commented that the Site should be renamed “Allied Industrial Park,” since DoD activities have ceased and the property is now commonly known as such. DoD, Cozen , and Unimax also commented that the property has been owned and operated by several different businesses and the EPA fails to discuss these other potentially responsible parties (PRPs), as well as failing to di scuss possible sources such as the Rocky Creek Water Reclamation Facility (RCWRF), Graphic Packaging (GP), and an adjacent NPL site that is currently being remediated.
DoD, Unimax, and Cozen commented that Source 1 has not been properly established and that the background sample used for Source 1 is insufficient to show that contamination is non-ubiquitous. Unimax and Cozen commented that a single source soil background sample is suspect also because it is a qualified value and merely an estimate.Macon Naval Ordnance Plant NPL Listing Support DocumentMay 20133Figure 1 – Map of the Macon Naval Ordnance Plant area showing the property boundaries, drainage ditches, wetlands, and 2011 sampling data.Macon Naval Ordnance Plant NPL Listing Support DocumentMay 20134Figure 2 – Large-scale map of the Macon Naval Ordnance Plant areashowing the neighboring facilities of Graphic Packaging Incorporated andArmstrong World Industries, and location of the background wetland sediment sample used to establish the observed release in Drainage Ditch#4.Macon Naval Ordnance Plant NPL Listing Support Document May 2013

Cozen and Unimax commented that only one background sediment sample used to establish an observed release is insufficient and not defensible to establish bac kground conditions, account for background variability, and attribute contamination to the former Macon Naval Ordnance Plant. Additi onally, Unimax and Cozen commented that this background sample (the observed release bac kground sample) was not taken from the same media as the observed release sample and is therefore insufficient to show sample similarity.
Unimax and Cozen commented that the mercury contamin ant concentration gradient in Drainage Ditch #4 does not support MNOP being the source of mercury contamin ation. Unimax commented that the HRS documentation record only obtained a small set of data focused around Building 109 and Drainage Ditch #4, and commented that a large volume of spatially extensive, high-quality, relevant data has been ignored. Unimax and Cozen commented that there are other sources of mercury in the area and that mercury discharges from GP and the Southern Wood Piedmont Company (SWPC) to the RCWRF had not been considered in attributing the mercury contamination to the MNOP site. Unimax also identified that the GP released mercury to the air and that GP should also be considered a possible source of the mercury.
Finally, Unimax commented that the probable point of entry (PPE) is located within a settling basin of the RCWRF in which the National Wetlands Inventory (NWI) characterizes the location as Emergent Wetland “PEM1Fx,” which is depicted as part of the RCWRF. 

### 3.1 Support for Listing and Other Non-opposition Comments

Comment : F. Allen Barnes, Director of the Georgia Depart ment of Natural Resources, expressed support for the placement of the Macon Naval Ordnance Plant site on the National Priorities List (NPL). Mr. Barnes stated that “[t]he NPL listing will help compel the PRPs to move forward with the investigation and remedial action that is needed at the Site.”
Response : The Macon Naval Ordnance site is being added to th e NPL. Listing makes a site eligible for remedial action funding under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), and the EPA will examine the Site to determine the appropriate response action(s). Actual funding may not necessarily be undertaken in the precise order of HRS scor es. In addition, upon more detailed investigation may not be necessary at all in some cases. The need for using Superfund monies for remedial activities will be determined on a site-by-site basis, taking into account the NPL ranking, State priorities, further site investigation, other response alternatives, and other factors as appropriate. 

### 3.2 Consistency with HRS

Comment : Unimax commented that the EPA failed to follow th e HRS in placing this site on the NPL, and as a result the placement of the Site on the NPL is arbitr ary and capricious. Unimax asserted that the EPA should withdraw its proposed listing of the Site.

Response 

### : The HRS evaluation of the Site is consistent with the HRS regulation and the Administrative Procedure Act (APA); EPA’s decision to add the Site to the NPL b ased on the HRS evaluation is therefore neither arbitrary nor capricious. The HRS documentation record at propo sal and this support document clearly document that EPA has complied with the HRS regulation; this support do cument addresses all comments on the proposed listing of this site, including those comments that challenge comp liance with the HRS, and shows that HRS requirements have been met in every aspect of the Site evaluation.

Section 553 of the APA authorizes “informal” rulema king. The informal rulemaking process encourages and relies on the participation of the public, including PRPs. The public can comment during the comment period (typically 60 days) after a site is proposed for listing and also during the time the Agency is evaluating and

5Macon Naval Ordnance Plant NPL Listing Support Document May 2013

selecting a remedy (the Agency may also hold a public hearing during the latter decision-making period). If private parties conduct remedial action under a Consent Decr ee between the EPA and the parties, the decree is also subject to public comment. The Agency believ es that the above process o ffers the public sufficient opportunity to present facts and opinions germane to its decision-making in a timely manner.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.2.1 Consistency with Guidance

Comment : Unimax asserted that the EPA failed to follow its own guidance in the HRS evaluation of the Site. Unimax specifically commented that the HRS Guidance Manual [ The Hazard Ranking System Guidance Manual; Interim Final , November 1992 ( NTIS PB92 -963377, EPA 9345.1-07)] was not followed when determining background concentrations a nd attributing mercury contamination to th e MNOP facility, concluding that “the background determination is arbitrary...” Unimax made th e following statements regarding the EPA’s use of the HRS Guidance Manual:

• EPA’s failure to explain why the off-site mercury impacts in Ditch #4 are not derived from the Rocky Creek Water Reclamation Facility (RCWRF) and the Gr aphic Packaging (GP) facilities is contrary to EPA’s HRS guidance.

• EPA’s failure to consider the RCWRF and the GP f acilities as sources of the mercury impacts detected in Drainage Ditch #4 and at the so-called “source area” on the former MNOP is contrary to EPA’s HRS guidance.

• According to EPA HRS Guidance, there is no source of mercury on the MNOP property.
Unimax asserted that these inconsistencies with guidance render the HRS evaluation arbitrary and capricious.


### Response : The EPA followed the HRS regulation to list the Site. Furthermore, the HRS Guidance Manual was also applied appropriately in the HRS evaluation based on the facts and circumstances presented for this site. The responses presented in this support document demonstrat e that the HRS evaluation was consistent with EPA guidance. The technical aspects of this comment are addr essed in this support document in sections 3.9, Source 1; 3.10, Observed Release – Background; and 3.11, Observed Release – Attribution.
Unlike the HRS regulation itself, the HRS Guidance Manual is not a regulation and imposes no mandatory requirements on the agency. The HRS Guidance Manual states that:
[t]he procedures set forth in this document are intended as guidance to employees of the U.S. Environmental Protection Agency (EPA), States, and other government agencies. EPA officials may decide to follow the guidance provided in this directive, or to act at variance with it, based on analysis of specific site circumstances.
In evaluating whether a site merits NPL listing, the EP A complies with the HRS regulation in the HRS evaluation and uses the HRS Guidance Manual as guidance to determin e how best to perform the evaluation based on the facts or circumstances presented at each site. The HRS Gu idance Manual is consistent with the HRS (this was not challenged by Unimax). As shown in this support docu ment, the EPA has followed the HRS in scoring the Site and applied the HRS Guidance Manual as appropriate to the S ite situation. EPA is therefore neither arbitrary nor capricious in the decision to list this site on the NPL.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

6Macon Naval Ordnance Plant NPL Listing Support Document May 2013



### 3.3 Site Name

Comment : The DoD commented that the Site should be rename d “Allied Industrial Park,” as several industrial businesses have owned and operated the property since th e DoD activities have ceased and the property is now commonly known as Allied Industrial Park (AIP).
Response : The Site name has not been revised. While neither CERCLA nor the NCP establishes a required procedure for assigning a site name to a proposed listing, in this case it is reasonable to have named the site the Macon Naval Ordnance Plant site. Since the primary purpose of an NPL listing is to inform the public that the site warrants further investigation, the attempt is made to select the name that most clearly informs the public as to the location of the site, what appears to be the primary so urce(s) of the problems at the site, and/or considers assigning a geographic name. The attempt is also made to select names that do not offend local sensitivities (see RSR Corporation v. EPA , 102 F.3d 1266 (D.C. Cir. 1997) ). The EPA chose to name the Site Macon Naval Ordinance Plant, as that site name is expected to have some degree of name-association to the public.

The site was named after the Macon Naval Ordnance Plan t, which was constructed a nd operated by the Reynolds Corporation before World War II for production of ordnan ce. The U.S. Navy assumed operations in 1941 and continued to manufacture ordnance at the MNOP until 1965. Ordnance manufactured at the MNOP included flares, small primers, detonators, and other triggering mechanisms. Page 13 of the HRS Documentation record at proposal states:
Explosive compounds were either handled or stored at many areas throughout the MNOP property, including numerous small dryer build ings, ordnance magazines, and blending and weighing houses (Ref. 13, pp. 11, 12, 54) (see Figure 2 of this HRS documentation record). According to a technical manual prepared by th e Department of the Army, military explosives, such as those that were manufactured at the MNOP, contained mercury compounds as initiating agents, including mercury fulminate (Ref. 23, pp. 7-5, 7-8). Building 109, located in the eastern portion of the MNOP, was a primary explosives production site (Ref. 13, pp. 11, 12, 54)
Importantly, the name of the Site does not in any way restri ct the evaluation of the Site, its sources, its releases, or extent of contamination to only the practices of th e Macon Naval Ordnance Plant. Any and all areas of contamination associated with the Site will be e xplored during further i nvestigation activities.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL. 

### 3.4 Liability

Comment : The DoD and Unimax commented that the MNOP property has been owned and operated by several different industrial businesses since DoD activity and opera tions have ceased. The DoD stated that “the current narrative...fails to discuss the other potentially responsible parties whose operations appear to be associated with the areas evaluated for this proposed listing.”
Response : Inasmuch as this comment addresses the owners and operators of the property on which the Site source is located, liability for site contamina tion is not considered when evaluating a site under the HRS, nor is liability established or apportioned based on the decision to place a site on the NPL. The NPL serves primarily as an informational tool for use by the EPA in identifying those sites that appear to present a significant risk to public health or the environment. It does not reflect a judgment on the activities of the owner(s) or operator(s) of a site. It does not require those persons to u ndertake any action, nor does it assign any liability to any person. This position, stated in the legisla tive history of CERCLA, has been explained more fully in the Federal Register (48 FR 40759, September 8, 1983 and 53 FR 23988, June 24, 1988). See Kent County v. EPA , 963 F.2d 391 (D.C. Cir. 1992).

7Macon Naval Ordnance Plant NPL Listing Support Document May 2013

This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL. 

### 3.5 Criteria for Listing

Comment : The DoD commented that the Site Narrative should identify and include one or more listing criteria as set forth in the NCP and stated that “[i]n this case, the applicable criterion appears to be the HRS score.” The DoD also asserted that the Site may not need listing becau se contamination may originate from a source area on an adjacent NPL site that is currently being remediated.
Response : The listing criteria are provided in the administrativ e record for this rulemaking, which includes the HRS documentation record and supporting materials, incl uding this support document. For prospective sites under consideration for listing on the NPL, the EPA follows NCP procedures by conducting a preliminary assessment (PA) of the site. Depending on the results, the PA may be followed up by a site inspection report (SI), which involves gathering more information about the site by contacting the state and interested parties on and around the site. When a site is proposed to the NPL, the EPA pr ovides its detailed rationale, including consideration of information gathered in the PA and SI, along with othe r site-related information in documents (i.e., the HRS documentation record and supporting materials) made public ly available at the EPA Headquarters in Washington, DC, in the Regional offices, and by electronic access at htpp://www.regulations.gov. In this case, the MNOP site qualifies for listing on the NPL; the Site has received an HRS score of greater than 28.50 and has met CERCLA and NCP listing criteria. Furthermore, the State concurred with the listing and stated that remedial action was needed at the Site. The purpose of NPL listing is expl ained in the Final Rule, National Priorities List for Uncontrolled Hazardous Waste Sites, published Febr uary 21, 1990 (55 FR 6154), excerpted below.
The purpose of the NPL, therefore, is primarily to serve as an informational and management tool. The initial identification of a site for the NPL is intended primarily to guide EPA in determining which sites warrant further investiga tion to assess the nature and extent of the public health and environmental risks associated with th e site and to determine what CERCLA-financed remedial action(s), if any, may be appropriate. The NPL also serves to notify the public of sites EPA believes warrant further investigation.
While remediation may be occurring on an adjacent N PL site, the source (Source 1) identified in the HRS documentation record at proposal warrants further investigation and there have been no efforts or plans to remediate the source as part of any other site. Furthermor e, the HRS evaluation of the MNOP site yielded a site score of 48.97; this score is substantia lly above the 28.50 score that qualifies a site for listing and is sufficient, in and of itself, to place the Site on the NPL.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL. 

### 3.6 Data Quality Issues

Comment : Unimax commented that the Tetra Tech 2011 data u sed in the HRS documentation record at proposal was not of “known and documented quality.” Specifically, Unimax commented that data validations and QA/QC procedures were not provided in the HRS documentation package for the 2011 assessment. Unimax concluded that “until evidence that QA/QC procedures were correc tly followed, the data from Tetra Tech, 2011 is not reliable.” Unimax also noted that the data used in the HRS documentation r ecord at proposal contained qualified data that “is merely an estimate (denoted by the ‘J-Val ue’)” and asserted that qualified data should not be used in the HRS evaluation.

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Response: The data used in the HRS evaluation were prope rly validated according to documented validation and QA/QC procedures, and are of known an d documented quality. In addition, qua lified data was used appropriately in this HRS evaluation. The analytical data used inthe HRS scoring of this site came from a June 2011 supplemental sampling event that was performed in acco rdance with the EPA Quality Assurance Project Plan (QAPP) for the sampling event, dated June 20, 2011. So il samples collected in this event were collected in accordance with the EPA Region 4 Science and Ecosys tem Support Division (SESD) Field Branches Quality System and Technical Procedure for Soil Sampling, November 2007 (SESDPROC-300-R1) (Reference 24 to the HRS documentation record at proposal) and sediment samp les were collected in accordance with the EPA Region 4 SESD Field Branches Quality System and Technical Procedure for Sediment Sampling, September 2010 (SESDPROC-200-R2) (Reference 25 to the HR S documentation record at proposal).
Regarding data validation, the June 2011 analytical da ta was reviewed, and validated in accordance with EPA procedures; therefore the data are of known and docum ented quality. Page 17 of the HRS documentation record at proposal states that “EPA Region 4 [Science and Ecosystem Support Division] SESD reviewed all data according to the laboratory contract statement of wo rk (SOW) and EPA guidelines (Refs. 28; 11, p. 1).” Reference 28 of the HRS documentation record at pr oposal, provides a description of how data review, validation, and verification is conducted in the EPA SESD program. Data validation reports and the QA/QC procedures for the June 2011 sampling event are provide d in References 10, 11, 26, 27, and 28 of the HRS documentation record at proposal.
Regarding the use of qualified data in the HRS evaluation, the U.S. Court of Appeals for the D.C. Circuit has specifically ruled on the use of analytical data in the scoring of a site using the HRS when there are possible weaknesses in the laboratory analysis. In the case of Board of Regents of the University of Washington v. EPA , 86 F.3d 1214 (DC Cir. 1996) , the Court, in response to the petitioner's challenge regarding the quality of the data used in an HRS evaluation—specifically , when there were issues dealing with the analysis—stated that “EPA does not face a standard of absolute perfection. . . . Rath er, it is statutorily required to ‘assure to the maximum extent feasible,’ that it ‘accurately assesses the relative degree of risk,’” [emphasis in original] and that “[i]t would hardly make sense for the courts to respond to the r esulting evidence by treating a lab’s findings as fatally defective whenever it comes up short in any way.” Also in this decision, the Court repeated a statement in an earlier NPL HRS case ( Eagle–Picher Indus., Inc. v. EPA , 759 F.2d. 905, 921, D.C. Cir. 1985 ) that explained the Agency has met its obligations when “[t]he EPA has thus ‘examined [the] relevant data and . . . articulated a rational explanation for its action.’” [addition of “the” in original]
Therefore, the data used in the HRS evaluation are of known and documented quality and are appropriate for use in the HRS evaluation consistent with th e intent of the HRS and court rulings.
See also section 3.9.2, Using Qualified Analytical Data that Impact the Quantification of Mercury in the Source Sample, of this support document, which addresses the tec hnical aspects of this comment regarding the use of analytical data and data quality.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL. 

### 3.7 Data Selection - Use of Previous Sampling Data

Comment : Unimax commented that other previous data sets (i.e., 2009 Region 4 SESD data completed by TetraTech and 1998 Rust data) are available for the Site that were not included in the HRS documentation record at proposal. Unimax commented that a large volume of spa tially extensive, relevant data has been ignored and that these other data sets show that the Site conditions were not adequately represen ted in the HRS documentation record at proposal. Unimax noted that the only data used in the HRS documentation record to justify NPL listing

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was obtained in a small sampling event in 2011, which s hows “an arbitrary selectivity in the use of the data.” Unimax claimed, “EPA’s failure to attempt to explain this contradictory data is arbitrary and capricious.”
Response : Contrary to Unimax’s assertions, all of the data sets that the commenter mentioned (2009 Region 4 SESD data completed by TetraTech, 1998 Rust data, and June 2011 Supplemental Sampling Event data) were relied upon in the evaluation of the MNOP site and were included in the HRS documentation record at proposal as references to the HRS documentation record. However, none of the data from the previous sampling events impacted the scoring of the MNOP site, so the most recent data (June 2011 Supplemental Sampling Event) was used in the HRS documentation record to most accurate ly represent the current conditions at the MNOP site.
While all of the data from all prior sampling events were considered in the evaluation of the MNOP site and are referenced in the HRS documentation record at proposal , the June 2011 Supplemental Sampling Event data was used to score the Site beca use this data is most recent and best represents current Site conditions. The 2009 Region 4 SESD data (referred to by Unimax as 2009 TetraT ech data) are included as References 7, 34 and 35 of the HRS documentation record at proposal and the 1998 Rust Report is included as Reference 13 of the HRS documentation record at proposal; the results from the prio r sampling events are consistent with the results from the June 2011 Supplemental Sampling Event and the HRS documentation record characterization of the Site, source, or observed releases.
The HRS documentation record at proposal uses the most current data (June 2011) to establish the presence of mercury in Source 1 and an observed release of merc ury downgradient in Drainage Ditch #4. The HRS requirements for identifying sources and the hazardous s ubstances associated with the source as well as the HRS requirements for establishing an observed release by chemical analysis have been met. All previous studies and additional data would be considered in performi ng other stages of the Superfund process after listing.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.



### 3.8 Site Definition

Comment : Unimax and Cozen made several comments using the term “onsite” to refer to the MNOP property and using the term “offsite” to refer to areas other than the MNOP property. Examples of these comments include:

• Unimax commented that elevated mercury samples “onsite,” as well as samples within Drainage Ditch #4, may have migrated from “offsite” sources.

• Sediment samples in Drainage Ditc h #4 that are consistently low in mercury, while “onsite” and exhibit elevated concentrations only in “offsite” portions of the ditch.

• Most “onsite” sediment concentrations are lower than those found in the most upgradient portions of Rocky Creek.
Response : In their comments, Cozen and Unimax incorrectly equated “site” with the MNOP property; whereas, as defined in the HRS, “site” refers to an area where a h azardous substance has been deposited, stored, disposed, or placed, or has otherwise come to be located, and is no t restricted by or defined by property boundaries. This response describes the meaning of “site” as used in the HRS documentation record and in this support document, and clarifies that the HRS defines the term “site” to encompass a different physical area than Cozen and Unimax referred to in their comments. The technical aspects of their comments are addressed in this support document in sections 3.9, Source 1; 3.10, Observed Release – Bac kground, and 3.11; Observed Release – Attribution.
HRS Section 1.1, Definitions, provides the definition for the term “site”:

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Site: Area(s) where a hazardous substance has been deposited, stored, disposed, or placed, or has otherwise come to be located. Such areas may include multiple sources and may include the area between sources.
Page 15346 of NPL Proposed Rule No. 56, publishe d March 15, 2012 (77 FR 15344) clarifies that:
the NPL site is not necessarily coextensive with th e boundaries of the installation or plant, and the boundaries of the installation or plant are not necessarily the ‘‘boundaries’’ of the site. Rather, the site consists of all contaminated areas within th e area used to identify the site, as well as any other location where that contamination has come to be located or from where that contamination came

. The HRS documentation record at proposal states that “[ f]or HRS scoring, the site consists of one source and associated releases.” Source 1 is contaminated soil on th e eastern section of the MNOP property, which contains elevated concentrations of mercury ove r background levels (see section 3.9, Source 1, of this support document). An associated release of mercury has al so been detected at significant levels in sediments collected in wetlands outside of the MNOP property boundaries that receive runoff from Source 1 via Drainage Ditch 4.
Therefore, a site is not associated with property or faci lity boundaries and the MNOP site is not confined to the MNOP property boundaries

. This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.



### 3.9 Source 1

Comment : The DoD, Unimax, and Cozen commented that Source 1 has not been properly established. These commenters asserted that the former MNOP is not the source of mercury contamination found at the Site and that Source 1 does not contain mercury contamination a bove levels found in the local environment.

Unimax commented that the HRS Site score should be 0 because the MNOP does not contain a source of mercury that contributes to the observed release. Unimax stated that “there appears to be no credible basis to assume that its [the EPA’s] ‘Source No. 1’ somewhere near Building 109 exists.” Unimax commented that other available data shows low levels of mercury c ontamination present on the western portion of the property “thousands of feet west of Drainage Ditch #4” and no mercury contamination on the eastern portion of the property where Source 1 is located. Unimax asserted that since the western portion of the property is not a plausible source of the mercury contamination found in the Drainage Ditch #4 samples, the Source sample “is not representative of site conditions...” and therefore Source 1 was not properly established.
Response: The HRS documentation record at proposal correc tly identifies Source 1 as a contaminated soil source on the MNOP property. Mercury contamination has been documented to be present at levels above background at the facility surrounding Building 109 as determined by sampling and documented in the HRS documentation record at proposal 1

.

1 This section of the support document d eals exclusively with samples that are us ed to establish Source 1. Background samples discussed in this section are not the same as the back ground sample that is used to establish the observed release sample (see Figures 1 and 2). While background samples are not required to establish site sources, as explained in section 3.9.1, Representativeness of the Background Sample, of this support document, Source 1 background samples were used solely to demonstrate that mercury contamination in Source 1 is elevated over natural mercury concentrations in the local environment. The commenters’ concerns about the observed release samples, in cluding the background sample used to establish an observed release, are discussed in section 3.10 , Observed Release – Background, of this support document.

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The HRS defines a site as “[a]ny area where a hazardous substance has been deposited, stored, disposed, or placed, plus those soils that have become contam inated from migration of a hazardous substance.”
The HRS directs the scorer to identify sources at each site. HRS Section 2.2.1, Identify sources, states:
For the three migration pathways, identify th e sources at the site that contain hazardous substances. Identify the migration pathway(s) to which each source applies. For the soil exposure pathway, identify areas of observed contamination at the site (see section 5.0.1).
HRS Section 2.2.2, Identify hazardous substances associated with a source , states:
For each of the three migration pathways, cons ider those hazardous substances documented in a source (for example, by sampling, labels, manifests, oral or written statements) to be associated with that source when evaluating each pathway.
The HRS documentation record at proposal documents th at the soil on the eastern portion of the MNOP property (specifically around Building 109) is contaminated with mercury. The HRS documentation record at proposal states on page 15:

Source No. 1 consists of contaminated soil on th e eastern portion of the MNOP property (Refs. 9, p. 3; 11, p. 8) (see Figure 3 of this HRS documentation record). MNOP operated as an ordnance manufacturing facility from before World War II until 1973 (Ref. 12, p. 1-1, 1-7). Ordnance manufactured at MNOP included flares, small primers, detonators, and other triggering mechanisms (Ref. 13, p. 2).
According to a technical manual prepared by th e Department of the Army, military explosives, such as those that were manufactured at the MNOP, contained mercury compounds as initiating agents, including mercury fulminate (Ref. 23, pp. 7-5, 7-8). Explosive compounds were either handled or stored in many areas throughout the MNOP property, including numerous small dryer buildings, ordnance magazines, and blending and weighing houses. Specifically, Building 109, located in the eastern portion of the MNOP n ear Source No. 1, was a primary explosives production site (Ref. 13, pp. 11, 12, 54) (see Figur es 2 and 3 of this HRS documentation record). Soil samples collected from this area during th e U.S. Army Corps of Engineers (USACE) 1996 site investigation and the EPA June 2011 supplem ental sampling event contained mercury (Refs. 9, p. 1; 11, p. 8; 13, pp. 58, 83, 84).
The HRS documentation record at proposal presents th e analytical results for Source 1 and the background sample on page 17:

TABLE 3: Analytical Results for Backgr ound and Source No. 1 Samples – June 2011
Sample Designation Sample ID Hazardous Substance Hazardous Substance Concentration MRL References

Background MNOP-01-SF Mercury 0.073J (0.13) mg/kg 0.050 mg/kg 11, pp. 4, 5; 31

Source No. 1 MNOP-04-SF Mercury 0.40 mg/kg 0.050 mg/kg 11, p. 8

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As presented above, the HRS documentation record at prop osal establishes Source 1 as an area of soil that has come to be contaminated by mercury, a hazardous substan ce. Analytical data presented show that contaminated soil is present at the facility surrounding Building 109 above naturally occurring levels. Additionally, historical operations in Building 109 have been documented in the HRS documentation record at proposal to include explosives production, which is known to have used merc ury compounds as initiating agents. The contaminated soil, as shown in the above table, has been documented to contain mercury at concentrations that are above background levels (mercury levels that would be naturally present, or ubiquitous) in the area surrounding Building 109 (see section 3.9.1, Representativeness of th e Background Sample, of this support document). Thus, the contaminated soil surrounding Building 109 (Source 1) is present as a result of hazardous substance migration from the historical operations in Building 109 and S ource 1 was properly established in the HRS documentation record at proposal.
The HRS documentation record at proposal demonstrates th at mercury concentrations in Source 1 are elevated over natural conditions by taking backgr ound samples at locations near Source 1 (see Figure 1) and comparing the source samples to these background samples. Source 1 merc ury concentrations were documented to be greater than the highest recorded background samples; thus, the HRS documentation record at proposal correctly established Source 1 as contaminated soil near Building 109.
Specific comments related to the Site source are addressed in the following subsections:

• 3.9.1 Representativeness of the Background Sample

• 3.9.2 Using Qualified Analytical Data that Impact the Quantification of Mercury in the Source Sample

• 3.9.3 Documenting Mercury Contamination in the Source Sample

3.9.1 Representativeness of the Background Sample

Comment: Unimax and Cozen commented that the background sa mple used for Source 1 is insufficient to show that contamination is non-ubiquitous in the area and due to former MNOP facility operations. Unimax asserted that without a sufficient number of background samples, a source cannot be determined at the Site. Unimax commented that GP has deposited low levels of contam ination throughout the property and asserted GP’s air emissions may be the cause of the contamination at S ource 1 and not the former MNOP facility operations.
Response: The HRS documentation record at proposal correc tly presented background concentrations to show that contamination is non-ubiquitous in the local envir onment and established Source 1 as contaminated soil near Building 109. The background sample used in the HRS documentation record at proposal to establish Source 1 as containing mercury concentrations above natural le vels (MNOP-01-SF) contained a detected mercury concentration of 0.073 mg/Kg. Source 1 was determined to have 0.40 mg/Kg mercury which is above the background sample and was correctly established in the HRS documentation record at proposal.
The HRS does not require background samples be taken to establish the presence of source contamination, rather, the HRS requires that the scorer identify sources at each site as stated in Section 2.2.1, Identify sources :
For the three migration pathways, identify th e sources at the site that contain hazardous substances. Identify the migration pathway(s) to which each source applies. For the soil exposure pathway, identify areas of observed contamination at the site (see section 5.0.1).
The HRS defines a source to be “[a]ny area where a hazar dous substance has been deposited, stored, disposed, or placed, plus those soils that have become contaminated from migration of a hazardous substance.”

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The HRS documentation record at proposal includes source background samples to establish that mercury contamination in Source 1 is elevated over naturally occu rring mercury levels in the local environment. Pages 16 and 17 of the HRS documentation record at proposal state:
The background and source soil samples listed in Table 2 were collected during the EPA June 2011 supplemental sampling event (Refs. 9, pp. 1, 3, 7, 9; 11, p. 3). The background soil sample was collected from the north-central portion of the MNOP property where no site-related activities have been known to occur (Refs. 8; 9, pp. 1, 3; 17, pp. 11, 17, 21, 25, 29, 33, 37, 41, 45). The source soil sample was collected from the eastern portion of the MNOP property where mercury has been previously detected, near where facility operations were known to have occurred and where explosives were handled and stored (Refs. 7, Appendix A, p. A-4; 9, p. 3; 13, pp. 11, 12, 54). The background and source surface soil samples were collected at a depth of 0 to 6 inches bgs (Refs. 9, p. 1; 10, Appendix B, p. B-1).
Background and Source No. 1 surface soil samples were collected during the same sampling event, from the same type of soil (sandy lo am), and in accordance with the same sampling procedures (Refs. 9, pp. 1, 6, 9; 10, p. 4; 30, pp. 1, 3). Surface soil samples were collected in accordance with the EPA Region 4 SESD Field Bran ch Quality System and Technical Procedures for Soil Sampling, SESDPROC-300-R1 (Refs. 9, p. 6; 10, p. 4; 24).

... Background and Source No. 1 samples listed in Tabl e 3 were analyzed for mercury in accordance with EPA Method 245.5 and the EPA Region 4 Analytical Support Branch (ASB) Laboratory Operations and Quality Assurance Manual (LOQAM), January 2011 (Refs. 9, p. 1; 11, p. 1; 27). EPA Region 4 SESD reviewed all data according to the contract statement of work (SOW) and EPA guidelines (Refs. 28; 11, p. 1). The mini mum reporting limits (MRL) are listed on the analytical data sheets in Reference 11. Each MRL is sample-specific and corresponds to the lowest quantitative point on the calibration curve; it is adjusted for the amount of sample prepared and any dilutions performed, as well as for percent moisture. The MRLs are equivalent to sample quantitation limits (SQL) (Ref. 29).
While the HRS does not require background samples to est ablish the presence of hazardous substances in sources, a background sample was used at this Site to establish elevated mercury concentrations in the source sample over naturally occurring levels of mercury in the local envir onment. Unimax correctly stated that an observed release determined by chemical analysis is established when the contaminant concentration in the observed release sample is three times or more above the background c oncentration; however, this criteria does not apply to identifying sources. As established in the HRS documen tation record at proposal, the background sample shows that mercury is not ubiquitous in the local soil and that Source 1 contains mercury at elevated levels compared to background concentrations.
The background sample identified in the HRS documen tation record at proposal contained a mercury concentration of 0.073 J (0.13) mg/Kg. The most accurate estimate of the true value of mercury in the background sample (MNOP-01-SF) is 0.073 mg/Kg mercury; however, in order to adjust for possible bias in the sample, or sample analysis, the sample concentration was adjusted. As a result, the HRS documentation record at proposal considers the background sample MNOP-01-SF to contai n 0.13 mg/Kg mercury to account for possible bias (see section 3.9.2, Using Qualified Analytical Data that Impact the Quantification of Mercury in the Source Sample, of this support document for using qualified data). Thus, the contaminated soil surrounding Building 109 has been established as containing contaminated soil related to Site activities.

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Even if the adjusted background sample concentra tion of mercury were 0.1336 mg/Kg as Unimax suggested, instead of 0.13 mg/Kg as in the HRS documentation record at proposal, this would have no effect on the identification of Source 1. The mercury concentration of 0.40 mg/Kg found in Source 1 is elevated above those values found to be present in the soil surrounding Source 1. Wh ile an argument could be made that natural levels of mercury in the local soil could be as high as 0.1336 mg/K g, the natural levels of me rcury were not found to be ubiquitous at the mercury concentrations found in Sour ce 1. Further, the commenter has not shown that the natural levels of mercury in the soil surrounding the Site contain concentrations of mercury above this established background level. Therefore, the background sample was correctly identified in the HRS documentation record at proposal and Source 1 was correctly established.
Regarding aerial deposition from the nearby GP facility , the HRS documentation record at proposal documents elevated concentrations of mercury surrounding Buil ding 109 on the MNOP property relative to background samples that were taken in nearby soils. While GP may have released mercury through air emissions that have settled throughout the MNOP property, the contaminat ed soil scored as Source 1 has been compared to background samples to determine that the contaminated soil is due to local deposits of mercury surrounding Building 109 on the MNOP property. Furthermore, if the mercury contamination is f ound to be more extensive than the existing preliminary sampling has indicated, then this will be considered in later stages of the Superfund process.
Finally, the commenters’ assertion that the HRS documentati on record at proposal includes an insufficient number of background samples to establish Source 1 is incorrect. While only one background sample is listed in the HRS documentation record at proposal, other soil samples were taken from nearby locati ons and also show that mercury is not a ubiquitous hazardous substance in the lo cal environment near Source 1. Four other soil samples were collected as part of the 2011 Supplemental Sampling Event (see Reference 9 of the HRS documentation record at proposal) near Source 1 and none of the sampl es contained mercury at a concentration higher than the sample reported as the background sample (MNOP-01-SF).
Therefore, the background sample used in the HRS documentation record at pr oposal is representative of the Site conditions and natural levels of mercury in the soil and was properly used to show that Source 1 contains elevated concentrations of merc ury over natural levels.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.9.2 Using Qualified Analytical Data that Impact the Quantification of Mercury in the Source Sample

Comment : Unimax and Cozen challenged the association of me rcury with Source 1. Unimax and Cozen asserted that the concentration of mercury in the source sample was not three times the concentration in the source background sample. The commenters argue d that the mercury concentration in the source sample was not three times the concentration in the background sample after the background concentration is adjusted upward to account for issues in the analysis of the sample.
Unimax and Cozen commented that the single source soil background sample is suspect because it is merely an estimate, denoted by the “J” value. Coze n stated that “there is significant doubt as to the utility of this soil sample” particularly when the difference between the source soil sample and background sample is 0.01 mg/Kg. Unimax stated “[w]hen analytical results are flagged by "J" ("estimated") qualifiers, the attendant uncertainty creates a problem in determining whether a release may have occurred.” Unimax furt her commented that “[t]he calculation of the background value is incorrect due to an arithmetic error” and when computed correctly, Unimax asserted that the soil sample contamination does not ex ceed three times background level. Unimax commented

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that although the correct analyte and medium-specific f actor for mercury in soil was used (1.83), “sufficient numerical precision” was not used.
Response: The use of qualified data and the possible bias associated with this analytical sampling data was accounted for in the association of mercury with Source 1. The mercury concentration in the source sample is sufficiently higher than in the background sample to doc ument that the soil in Source 1 is contaminated with mercury. Thus, mercury is correctly associated with the source. The HRS does not require that the increase between the background and source sample contaminati on be three times the background level (i.e., observed release criteria) to demonstrate that a source is contaminated with a hazardous substance. The HRS only requires the contaminant be present at the source.
HRS Section 2.2.2, Identify hazardous substances associated with a source , states how to associate hazardous substances with a source:
For each of the three migration pathways, cons ider those hazardous substances documented in a source (for example, by sampling, labels, manifests, oral or written statements) to be associated with that source when evaluating each pathway.
The HRS documentation record at proposal presents th e analytical results for Source 1 and the background sample on page 17:

TABLE 3: Analytical Results for Backgr ound and Source No. 1 Samples – June 2011

Sample Designation Sample ID Hazardous Substance Hazardous Substance Concentration MRL References

Background MNOP-01-SF Mercury 0.073J (0.13) mg/kg 0.050 mg/kg 11, pp. 4, 5; 31

Source No. 1 MNOP-04-SF Mercury 0.40 mg/kg 0.050 mg/kg 11, p. 8

As shown in Table 3, the mercury level in the b ackground sample (MNOP-01-SF) was reported as 0.073 mg/kg and assigned a data quality qualifier of a J (in this case, a J qualifier means that the identification of the analyte is acceptable, but the reported value is an estimate due to la boratory issues). The addition of a qualifier to the data does not mean the reported data value is incorrect, rather, the addition of a qualifier to the data only cautions the user that the reported value might be slightly inexact due to possible bias. However, the reported (qualified) value is the best estimate of the true value of mercury in the surrounding soils and the adjusted value (0.13 mg/kg) is an estimate of the highest concentration that could have been present in the sample if the sample were biased low 2

. The HRS documentation record at proposal uses the adju sted value of 0.13 mg/Kg mercury to establish the natural levels of mercury concentrations and t hus provides a reasoned estimate of mercury background concentrations in the soil surrounding Source 1 (see secti on 3.6, Data Quality Issues, of this support document, regarding the use of qualified data in the HRS evaluation).
The commenters incorrectly calculated and asserted that the difference between the background sample and source sample is 0.01 mg/Kg. To reach this numbe r, the commenters adjusted the background sample

2 Biased low means that the true concentr ation of the hazardous substance in the sample, if no quality control issues were identified, might be greater than the measured laboratory value. Thus, the ad justed value represents the maximum concentration of that substance that could be present in th e sample. However, the adjusted value does not necessarily represent a more accurate value or the true value.

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concentration (0.13 mg/kg), multiplying it by 3 for a total of 0.39 mg/kg, then compared the adjusted background sample concentration (0.39 mg/kg) to the Source 1 sample concentration (0.40 mg/kg) to calculate the difference of 0.01 mg/kg. Multiplying the background sample concentration by 3 is incorrect when determining the natural levels of a contaminant in the local environment for the purpose of establishing a source during an HRS evaluation (see sections 3.9, Source 1; and 3.9.3, Documenting Mercury Contamination in the Source Sample, of this support document). The HRS does not require source samples to be 3 times the background concentration to establish natural levels of a contaminant in the local e nvironment. The HRS only requires that a source be an area where hazardous substances have been “deposited, stored, disposed, or placed...” and that the site source contain a hazardous substance(s) available to a pathway (at this site, the surface water pathway). The HRS documentation record at proposal uses the background concentration valu e (0.13 mg/Kg) to determine the natural levels of mercury in the local environment; therefore, Sour ce 1 was properly established as containing mercury contamination above background leve ls and contains contamination due to Site-related activities.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.9.3 Documenting Mercury Contamination in the Source Sample

Comment : The DoD, Unimax, and Cozen commented that the number of source samples and background source samples raises uncertainty about the identification of Source 1. Unimax stated that “[t]he proposed listing is based on comparing one background surface soil sample to a singl e soil sample obtained at the Site in 2011.” Unimax further stated that comparing one background soil sample to only one other soil sample is “an insufficient quantity of samples to establish a background concentration and th erefore the data does not indicate a release.” Unimax asserted that without a sufficient number of background samples, a source cannot be determined at the Site.
Response: The HRS documentation record at proposal co rrectly establishes Source 1 contaminated soil as containing a hazardous substance at concentrations a bove background levels. Background samples are used to show that soil contamination in a source is above natural levels in the local environment. The HRS does not require that multiple samples be taken to identify a sour ce or to determine background concentrations, and Source 1 was correctly established in the HRS documentation reco rd at proposal as containing contaminated soil above background concentrations.
As quoted in section 3.9, Source 1, of this support documen t, the HRS directs the scorer to “identify the sources at the site that contain hazardous substances.” Source 1 was correctly identified and established in the HRS documentation record at proposal as being contaminated soil near Building 109.
While the HRS does not require background samples (or multiple background samples) for source soil samples, and the HRS documentation record at proposal only lists one background sample under Source 1, other soil samples were taken from nearby locations (see Reference 9, June 2011 Supplemental Sampling Event, of the HRS documentation record at proposal). These other sampl es show that mercury is not a ubiquitous hazardous substance near Source 1 (see Figure 1 of this support document, and page 3 of Reference 9 of the HRS documentation record at proposal). None of the four othe r soil samples that were collected as part of the 2011Supplemental Sampling Event contained mercury at a concentration higher than the background sample (MNOP01-SF) used in establishing Source 1.
Therefore, the background sample used in the HRS docume ntation record at proposal in establishing Source 1 is representative of the Site conditions, and was properly used to show that Source 1 contains elevated concentrations of mercury over the natura l levels present in the surrounding soil.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

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### 3.10 Observed Rele ase – Background

Comment : Unimax and Cozen commented that the background sa mple used to establish an observed release was determined incorrectly, contained an insufficient number of background samples, and was not of the same media as the observed release sample.
Response: A single valid background sample for mercury in surface water is sufficient to identify that a significant increase in the mercury concentration in the release sample (used to establish an observed release to surface water) has been documented. While the background level assigned is based on a single sample, this level is supported by other samples taken in the vicinity of the site. The background sample (MNOP-W-01-SD; see Figure 2) is located west and upgradient of Drainage Ditch #4 in the same wate rshed and same wetland as the observed release sample and from the same medium, without the potential influence from the MNOP facility (see Figure 2 of this support document and Figure 3 of the HRS documentation record at proposal).
The HRS addresses background in the context of identifying an observed release of a hazardous substance to the environment by chemical analysis. HRS Section 4.1.2.1.1, Observed release , states in relevant part:

Establish an observed release to surface water for a watershed by demonstrating that the site has released a hazardous substance to the surface wate r in the watershed. Base this demonstration on either:

• Direct observation: . . .

• Chemical analysis:

- Analysis of surface water, benthic, or sediment samples indicates that the concentration of hazardous substance(s) has increased significantly above the background concentration for the site for that type of sample (see section 2.3)

- Limit comparisons to similar types of samples and background concentrations—for example, compare surface water samples to surface water background concentrations.

- ...

• Some portion of the significant increase must be attributable to the site to establish the observed release, except: when the site itself consists of contaminated sediments with no identified source, no separate attribution is required.
If an observed release can be established for a watershed, assign an observed release factor value of 550 to that watershed, enter this value in Table 4-1, and proceed to section 4.1.2.1.3... In establishing whether a hazardous substance is signifi cantly above background concentrations, HRS Section 4.1.2.1.1 refers the scorer to HRS Section 2.3 for requ irements for establishing significant increases in hazardous substance concentrations. HRS Section 2.3, Likelihood of release , specifies that the scorer is to “[u]se the criteria in Table 2-3 as the standard for determining analytical significance.” HRS Table 2-3 states:

An observed release is established as follows:

• If the background concentration is not detected (or is less than the detection limit), an observed release is established when the sample measurement equals or exceeds the sample quantitation limit.

18Macon Naval Ordnance Plant NPL Listing Support Document May 2013

• If the background concentration equals or ex ceeds the detection limit, an observed release is established when the sampl e measurement is 3 times or more above the background concentration. Based on HRS Table 2-3, the purpose of the backgrou nd sample is to establish a background level (the concentration of a hazardous substance) for the Site that provides a reference point to evaluate whether a release has occurred.
HRS Section 4.1.2.1.1, Observed Release , in part states that samples should be compared to similar types of samples:

... • Chemical analysis:

... –Limit comparisons to similar types of samples and background concentrations—for example, compare surface water samples to surface water background concentrations...
Thus, a background sample should be located in the sam e media as the release samples being evaluated and outside of any potential impacts from facility operations. Background samples are used to demonstrate an increase in hazardous contamination due to fac ility operations and provide a reference point for contamination that may be naturally present in the local environment
The HRS documentation record at proposal on page 22 explains the rationale for the establishment of a background level at the MNOP site:
During the EPA June 2011 supplemental sampli ng event, one background sediment sample, MNOP-W-01-SD, was collected from HRS-eligible palustrine forested wetlands west of and upgradient from Drainage Ditch 4. Contamin ated sediment sample MNOP-D4-W-09-SD was collected from Drainage Ditch 4 within HRS-eligib le palustrine forested wetlands downstream of the PPE. Background and contaminated sediment samples were collected from HRS-eligible palustrine forested wetlands at depths ranging from 0 to 3 inches bgs (Refs. 9, pp. 1, 3, 8, 9; 36, Map 1).
The sediment samples were coll ected in accordance with the EPA Region 4 SESD Field Branches Quality System and Technical Procedures for Sediment Sampling, SESDPROC-200-R2 (Refs. 9, pp. 1, 6; 10, p. 4; 25)...
The background and contaminated sediment samples were collected during the same sampling event, in accordance with the same sampling procedures, and from the same type of HRS-eligible wetland (palustrine forested).(Refs. 9, pp. 1, 3, 6;36) (see Figure 3 of this HRS documentation record).
Table 7 from page 23 of the HRS documentation record at proposal, provides the background and observed release samples as follows:

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TABLE 7: Analytical Results for Background and Contaminated Sediment Samples – June 2011
Sample Description Sample ID Hazardous Substance Concentration MRL References
Background MNOP-W-01-SD Mercury 0.16J (0.29) mg/kg 0.050 mg/kg 11, pp. 4, 22; 31; 32, pp. 8, 18

Release MNOP-D4-W-09-SD Mercury 1.1 mg/kg 0.050 mg/kg 11, p. 21

The commenters’ specific issues with this background level determination are addressed in the following subsections:

• 3.10.1 Adequacy of Background Sample – Observed Release

• 3.10.2 Sample Similarity

• 3.10.3 Number of Samples used to Identify an Observed Release

3.10.1 Adequacy of Background Sample - Observed Release

Comment : Cozen and Unimax commented that the single obser ved release background sample, which is intended to provide a defensible reference to evaluate whether a release from the s ite has occurred, is insufficient to determine attribution of mercury in Drainage Ditch #4 to the former MNOP. Cozen and Unimax added that observed release samples must be significantly greater than the background concentration. Unimax asserted that the determination of the observed release sample (MNOP-D4-W-09-SD) to be significantly greater than background contamination levels is incorrect.
Unimax commented that the sediment samples found in th e upper portions of Drainage Ditch #4 contain lower concentrations of mercury than in the background sam ple, and that in 2009 TetraTech considered the upper portion of Drainage Ditch #4 to be background. Unimax stated that for the sample to be considered a release, the concentration must exceed three times the background; which “strongly suggests the background determination [in the HRS evaluation] is arbitrary and contradicted by the additional data contained in the HRS references.”
Response: The background level established in the HRS documentation record at proposal, based on the single observed release background sample, is sufficient for identification of a significant increase in mercury concentrations consistent with the HRS. The background sample was taken from the same palustrine forested wetland and upgradient of any release from Source 1. Howe ver, this background sample was not the only sample used to establish the background level.
Other samples considered in establishing the background level include those samples taken from Drainage Ditch #4 upgradient of the observed release sample in Drai nage Ditch #4. These samples in the upper portions of Drainage Ditch #4 showed mercury concentrations ra nging from non-detect (0.050 mg/kg in samples MNOP-D4- 01-SD, MNOP-D4-02-SD-DUP, MNOP-D4-03-SD, MNOP-D 4-05-SD, and MNOP-D4-06-SD) to 0.083 mg/kg in sample MNOP-D4-04-SD.
These samples show that the background mercury level in th e vicinity of the Site is no more than the background concentration of the designated mercury background sa mple. These samples are located upgradient of the release sample location but were not considered for background sam ples as they are part of the contaminant migration pathway from Building 109 at the MNOP site . However, as discussed in section 3.11.2, Contaminant Concentration Gradient in Drainage Ditch #4 , of this support document, these samples contain different

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streambed morphologies and thus may not have elevated me rcury concentrations due to this difference, but the absence of mercury contamination in these upgradient samples indicates that mercury is not ubiquitous.
In addition to the 2011 Supplemental Sampling Event samp les, Reference 7 of the HRS documentation record at proposal includes analytical data from an Expanded S ite Inspection that includes samples taken from Rocky Creek upgradient of the confluence with Drainage Ditc h #1 (and upgradient of Drai nage Ditch #4). Samples RC400-SD, RC-401-SD, RC-402-SD and RC-403-SD (sample locat ions are shown in Figure 4 on page A-4 of Reference 7 of the HRS documentation record at propo sal) of the Expanded Site Inspection all contain mercury levels that are below the detection limit and less than th e concentration identified in background sample MNOPW-01-SD (see page B-110 of Reference 7 of the HRS documentation record at proposal).
However, background sample MNOP-W-01-SD was collected from the same HRS-eligible wetland west of the observed release sample (MNOP-D4-W-09-SD) which had si milar background conditions as the release sample location and was collected during the same sampling event; therefore this sample 

### is sufficient for identifying a significant increase in mercury conc entrations in Drainage Ditch #4.

Insomuch as this comment addresses the attribution of mercury at the Site, section 3.11, Observed Release – Attribution, of this support document further addresses the attribution component of establishing a release by chemical analysis to the Site.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.10.2 Sample Similarity

Comment : Cozen commented that the EPA failed to explain why a sample obtained from palustrine forested wetlands, west of Drainage Ditch #4, was used for the background concentration to establish an observed release by chemical analysis. Cozen asserted that the background sample was “apparently not [collected] from sediments in a stream and/or drainage ditch” and is not in the same media as the observed release sample (i.e., sediment to sediment). Cozen and Unimax commented that samples used for comparison purposes must be from the same media.
Response: The background level was correctly established cons istent with the HRS. The background sample was collected in a similar environment and in the same media as the release sample. The background sample was taken upgradient of the release samples in Drainage Ditc h #4, in the same palustrine wetland, using the same sampling procedures, and at the same time the release samples were collected (see Figure 3 of the HRS documentation record at proposal). For HRS purposes, th e sample similarity of background sample (MNOP-W01-SD), collected in palustrine forested wetlands and cons idered a surface water sample, is correctly compared to the surface water observed release sample (MNOP-D4-W-09-SD), collected from Drainage Ditch #4, as they are both surface water samples.
As defined by HRS Section 4.0.2, Surface water categories , surface water is defined in part as follows:
For HRS purposes, classify surface water into four categories: rivers, lakes, oceans, and coastal tidal waters.

-Rivers include:

• Perennially flowing waters fro m point of origin to the ocean or to coastal tidal waters, whichever comes first, and wetla nds contiguous to these flowing waters.

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HRS Section 4.1.2.1.1, Observed Release , in part states that samples should be compared to similar types of samples:

... • Chemical analysis:

... –Limit comparisons to similar types of samples and background concentrations—for example, compare surface water samples to surface water background concentrations...
Thus, the purpose of a background sample is to establish a background level in the medium of concern for the site to determine whether or not a release from the site has occurred. Background samples should be taken from the same media (surface water, sediment, soil, etc.) and should be sufficiently similar to re lease samples to ensure the increase in contamination between the background level and the release sample is due to a release and not due to differences in the samples or the analysis.
Page 22 of the HRS documentation reco rd at proposal identifies that th e background and release samples were collected from the same surface water body:
The background and contaminated sediment samples were collected during the same sampling event, in accordance with the same sampling procedures, and from the same type of HRS-eligible wetland (palustrine forested) (Refs. 9, pp. 1, 3, 6; 36).
Hence, both background and observed release sediment samp les were collected from the same HRS-eligible 3 palustrine forested wetlands, within the same watershe d and are thus considered taken from the same media. Additionally, as stated in the HRS documentation record at proposal, the background sample was taken during the same sampling event, under the same physical conditions (i .e., weather, season, etc.), and used the same sampling, handling, and analytical procedures as the release sampl es. Therefore, the similarities of the background and release samples at this Site are considered sufficiently si milar to ensure the significant increase is not simply due to difference in the sample media or to differences in sampling and analysis procedures, and the significant increase criteria for establishing an observed release have been met.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.10.3 Number of Background Samples Used to Identify an Observed Release

Comment : Cozen and Unimax commented that only one b ackground sediment sample used to establish an observed release is insufficient and not defensible to establish background conditions, account for background variability, and attribute contamination to the former Macon Naval Ordnance Plant.
Response : The background level is sufficiently supported to establish a significant increase in the mercury level in the release sample consistent with the HRS. In establishing an observed release, a background concentration is used to show that contamination in the release sample is significantly above those levels that occur naturally in the local environment or significantly above those levels that are present due to other nearby facilities. The HRS does not require that multiple samples be taken to id entify an observed release or to determine background

3 Wetlands are considered HRS-eligible if they meet the criteri a defined in 40 CFR Section 230.3. Generally this definition includes areas that are inundated by surface or ground water at a frequency and duration sufficient to support a prevalence of vegetation typically adapted for life in saturated soil conditions.

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concentrations, rather, the background level is used to s how that observed release contamination is significantly above background levels.
HRS Section 4.1.2.1.1, Observed release , states in relevant part:

Establish an observed release to surface water for a watershed by demonstrating that the site has released a hazardous substance to th e surface water in the watershed. The HRS does not require multiple background samples to establish an observed release by chemical analysis. However, as noted in section 3.10.1, Adequacy of Bac kground Sample - Observed Release, of this support document, Reference 7 of the HRS documentation record at proposal contains additional samples from Rocky Creek upgradient of the release sample that contain mercury concentrations be low the background level established by sample MNOP-W-01-SD in the HRS document ation record at proposal (see Figure 4 and page B110 of Reference 7 of the HRS documentation record at proposal). Nevertheless, the observed release was established based on a significant incr ease in the concentration of mercury in sample MNOP-D4-W-09-SD (1.1 mg/kg) as compared to background sample MNOP-W-01-SD (0.29 mg/kg). Mercury is not naturally occurring at the levels found in the release sample and therefore the b ackground sample is sufficient and consistent with the HRS.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.



### 3.11 Observed Release - Attribution

Comment : Unimax commented that the attribution of mercur y contamination to the former MNOP site was not properly established and that the EPA had not considered th at the mercury could have come from alternative sites. Unimax commented that although low levels of mercury are present on the MNOP property, the property is not the source of any downstream contamination. Unimax asser ted that the additional data contained in the HRS documentation package contradicts the determination of attr ibution to the MNOP site due to faulty analysis and the failure to consider alternative sources.
Response: The significant increase of mercury contamination in Drainage Ditch #4 was correctly attributed to the MNOP site consistent with the HRS.
HRS Section 2.3, Likelihood of release , presents the basic requirements for establishing an observed release including attribution to the site in relevant part:
Establish an observed release either by direct ob servation of the release of a hazardous substance into the media being evaluated (for example, surf ace water) or by chemical analysis of samples appropriate to the pathway being evaluated (see s ections 3, 4, and 6). The minimum standard to establish an observed release by chemical analysis is analytical evidence of a hazardous substance in the media significantly above the background level. Further, some portion of the release must be attributable to the site . [emphasis added]
HRS Section 4.1.2.1.1, Observed release , contains specific instructions on establishing observed releases to surface water, and states in relevant part:

Establish an observed release to surface water for a watershed by demonstrating that the site has released a hazardous substance to the surface wate r in the watershed. Base this demonstration on either:

• Direct observation: . . .

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• Chemical analysis:

- Analysis of surface water, benthic, or sediment samples indicates that the concentration of hazardous substance(s) has increased significantly above the background concentration for the site for that type of sample (see section 2.3)

- Limit comparisons to similar types of samples and background concentrations—for example, compare surface water samples to surface water background concentrations.

- ...

- Some portion of the significant increase mu st be attributable to the site to establish the observed release , except: when the site itself consists of contaminated sediments with no identif ied source, no separate attribution is required. [emphasis added]
Thus, there are two parts to establishing an observed releas e by chemical analysis for the ground water migration pathway: first, establishing a significant increase in contaminant concentrations, and second, attributing at least part of the increase to the site.

Attribution of a release to a site is also established in two steps. First it is documented that the released substance(s) is associated with sources at the site and th at containment for the HRS component or pathway is not such that the release could not occur. Second, it is show n that not all of the significant increase in the released hazardous substances could have come from other sites (i.e ., that part of the increase came from the site).
As discussed in section 3.10, Observed Release – Ba ckground, of this support document, the background hazardous substance (mercury) level was correctly establis hed in the HRS documentation record at proposal. The background level allows for a significant increase of a hazardous substance in a release sample to be identified. A significant increase in the concentration of mercury was established in sample MNOP-D4-W-09-SD as detailed in section 4.1.2.1.1, Observed Release, of the HRS docum entation record at proposal (see Figure 1) and the commenters did not challenge that the mercury contamina tion in this established background sample can also support the attribution of the release to the Site.
Pages 25 and 26 of the HRS documentation record at propo sal establish that some portion of the observed release is attributable to the Site, stating:

The MNOP was constructed before Worl d War II and was operated as an ordnance manufacturing facility until 1973 (Refs. 12, p. 1-1; 13, p. 2)...
Explosive compounds were either handled or stored in many areas throughout the MNOP property, including numerous small dryer build ings, ordnance magazines, and blending and mixing houses (Ref. 13, pp. 11, 12, 54). Accord ing to a technical manual prepared by the Department of the Army, military explosives, such as those that were manufactured at the MNOP, contained mercury compounds as initiating ag ents, including mercury fulminate (Ref. 23, pp. 7-1, 7-5, 7-8). Build ing 109, located in the eastern portion of the MNOP near Source No. 1, was a primary explosives production site (Ref. 13, pp. 11, 12, 54) (see Figures 2 and 3 of this HRS documentation record). Soil samples collect ed from this area during the USACE 1996 site investigation and EPA June 2011 supplemental sampli ng event contained mercury (Refs. 9, p. 3; 13, pp. 58, 83, 84).

...
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The HRS documentation record at proposal continues by discussing association of mercury contamination with the Site source:
The source sample collected from Source No. 1 (contaminated soil on the eastern portion of MNOP) during the EPA June 2011 supplemental sampling event contained mercury (Refs. 9, p. 3; 11, p. 8) (see Table 3 in Section 2.2.2 for Source No. 1 of this HRS documentation record). Sediment samples collected from Drainage Ditc h 4, which receives runoff from Source No. 1, also contained mercury. The presence of mercury in Drainage Ditch 4 documents the migration of releases from Source No. 1 at the MNOP (Refs. 9, p. 3; 11, pp. 13, 16, 19, 20, 21) (also see Tables 6 and 7 in Section 4.1.2.1.1, Observed Release, of this HRS documentation record). Furthermore, an observed release of mercury has been documented in HRS-eligible wetlands along Drainage Ditch 4 (Refs. 9, p. 3; 11, p. 21; 36).
Mercury has been documented in Source No. 1, in Drainage Ditch 4 and in palustrine forested wetlands indicating migration of hazardous substa nces from the MNOP property (see Table 3 in Section 2.2.2 for Source No. 1, and Table 7 in Section 4.1.2.1.1, Observed Release, of this HRS documentation record).
The following subsections address specific comments rega rding the attribution of the significant increase in mercury to the MNOP site:

• 3.11.1 Possible Mercury Releases from Alternative Sites

• 3.11.2 Contaminant Concentration Gr adient in Drainage Ditch #4

• 3.11.3 Contaminant Concentration Downgradient of the RCWRF

• 3.11.4 Other Data Sets

3.11.1 Possible Mercury Releases from Alternative Sites

Comment : Unimax and Cozen commented that the mercury c ontamination found in the observed release sample cannot be attributed to the former MNOP and the EPA has failed to consider other sites which may be causing the mercury contamination.
Unimax commented that the following possible contri butors of mercury to Drainage Ditch #4 were not investigated in establishing attribution of the me rcury in the release samples to the MNOP site:

• Rocky Creek Water Reclamation Facility (RCWRF)

• Graphic Packaging International, Inc. (GP)

• Southern Wood Piedmont Company

• “Off-site source areas north of the site”
Unimax commented that the mercury contamination in th e release sample is due to operations at facilities other than the MNOP facility. Unimax asserted that while mercury contamination ma y be present in the area, it is not due to operations at the MNOP facility and the significant increase found in the release sample in Drainage Ditch #4 is due to releases from the RCWRF. Unimax stated that the “EPA’s failure to explain why the off-site mercury impacts to Ditch #4 are not derived from the RCWRF and the GP facilities is contrary to EPA’s HRS guidance.” Unimax concluded its comment by stating that since th e former MNOP is not the source of contamination in Drainage Ditch #4, the HRS Site score should be 0.

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Response: The significant increase in mercury concentrati on found in the release sample (MNOP-D4-W-09-SD) in Drainage Ditch #4 is correctly attributed to the MNOP site and not to any alterna tive sites. Other alternative facilities that could impact the level of mercury contam ination in the release sample were considered and described in the HRS documentation record at proposal and, at that time, were found not to be the source of the mercury in the observed release in Drainage Ditch #4.
The HRS documentation record at proposal on pages 25-26 discusses other nearby facilities and their possible contributions to the mercury contamination, stating:
Other facilities in the area include the MBCIA, which renamed the MNOP property the Allied Industrial Park and currently leases or sells bu ildings as office and warehouse space to various industrial and commercial businesses on the AIP property (Refs. 7, Appendix A, p. A-3; 13, pp. 1, 2, 3; 14, p. 2-9; 15). Politex U S Inc. (P olitex) is the only manufacturing business that is currently located at the AIP. Politex is a textile manufacturing firm that produces roofing membranes, clothing and furniture padding, and building materials (Ref. 15). Politex is located on the western portion of the MNOP property (Refs. 6, pp. 42 through 49; 7, Appendix A, p. A-3). Runoff and drainage originating from Politex does not enter Drainage Ditch 4 (Ref. 7, Appendix A, pp. A-2, A-3) (see Figure 3 of this HRS documentation record). The property where Source No. 1 soil sample MNOP-04-SF was collected is ow ned by the City of Macon and is operated as a recreational park that includes baseball fields (Refs. 6, pp. 7, 8; 7, Appendix A, pp. A-2, A-3; 9, p. 3).
Possible off-site sources also include the FMNOL, AWI, and the Rocky Creek water reclamation facility (RC WRF). AWI and FMNOL are currently listed on the EPA NPL under CERCLIS ID No. GAN000410033 at docket number EPA- HQ-SFUND-2010-0640-0002 (Ref. 47). Runoff from FMNOL and AWI flows into Rocky Creek via a drainage easement. The drainage easement enters Rocky Creek west and upstream of Source No. 1 soil sample MNOP-04-SF and Drainage Ditch 4. Drainage Ditch 4 is located just west of the RC WRF (Ref. 7, Appendix A, p. A-2).
The FMNOL was reportedly used for disposal of solid wastes and ordnance throughout the operational history (1941 to 1974) of the MNOP (Refs. 8; 17, pp. 42, 43, 46, 47; 18, p. 2). The landfill was also used for disposal of used parts a nd construction debris (Refs. 14, p. 2-11; 18, p. 2). During the EPA May 2009 ESI, mercury was detected in soil sampl es collected from the FMNOL at concentrations ranging from 0.47 mg/kg (FML-303-SF) to 4.7 mg/kg (FML-304-SB) (Ref. 35, pp. 130, 132).
Since 1948, AWI has operated an acoustic ceili ng tile manufacturing plant on 130 acres of land west of the MNOP property (Ref. 19, p. 3). In 1980, AWI notified the Georgia Environmental Protection Division (GAEPD) that it was a generator of hazardous waste and AWI was classified as a conditionally exempt small quantity generator under the Resource Conservation and Recovery Act (RCRA). PCBs are the primary hazar dous substance of concern for this facility, not metals (Ref. 19, pp. 5, 6).
The RC WRF, located southeast of and downstream from MNOP, provides wastewater treatment for the southern and western portions of the City of Macon. Treated wastewater from this facility is discharged into the Ocmulgee River; how ever, RC WRF maintains a National Pollutant Discharge Elimination System (NPDES)-permitted discharge point at the southern property boundary (Refs. 9, p. 3; 45, pp. 2, 3; 46, pp. 1, 8). The NPDES permit requires RC WRF to monitor outfall discharges for biochemical oxygen demand, total suspended solids, pH, chlorine, fecal coliform, nitrogen, dissolved oxygen, PCBs, and phosphorus (Ref. 46, pp. 6, 7). There are currently no documented releases of mercury at th is location (Refs. 9, p. 3; 46, pp. 6, 7).

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27 All nearby facilities were considered in the evaluation of possible contributors of contamination at the Site; however, the evaluation has not documented any evidence of these other off-site facilities contributing to the significant increase of mercury in the observed releas e sample. The evaluation also does not negate EPA’s determination that some portion of the significant increase in mercury levels is attributable to the Site. The following subsections address the specific off-site facilities that Unimax asserted may be potentially contributing to the mercury contamination at the Site:

• 3.11.1.1 Wastewater Discharges from GP and th e Southern Wood Piedmont Company via the RCWRF

• 3.11.1.2 GP Air Emissions

• 3.11.1.3 Contribution of Sources West and North of Source 1

3.11.1.1 Wastewater Discharges from GP and the Southern Wood Piedmont Company via the RCWRF

Comment: Unimax commented that mercury discharges fro m GP and SWPC to the RCWRF had not been considered in attributing the mercury release to the MNOP site. Unimax commented that both GP and SWPC have been documented to historically send wastewat er containing mercury to the RCWRF. Unimax commented that the RCWRF has treated wastewater containing me rcury since its construction and that the RCWRF has historically been in non-compliance with its National Pollution Discharge Elimination System (NPDES) permit for discharge of organic waste. Further, Unimax commented that the HRS documentation record appears to conclude that since the RCWRF does not currently monitor fo r mercury it cannot be a current or historic source of the mercury contamination found in Drainage Ditch #4. Unimax asserted that RCWRF discharge into Drainage Ditch #4 is responsible for the increase in mercury in the observed release sample.
Response: The possibility of mercury being discharged from th e RCWRF due to the inputs of discharge from GP and SWPC to the RCWRF was considered as a possible c ontributor to the increase in mercury contamination in the observed release sample in Drainage Ditch #4. Ho wever, discharges from the RCWRF were found not to be contributing to the mercury contamination to Drainage Ditch #4. The historic effluent outfall from the RCWRF (from 1975 to 1991) was directly to the wetlands located to the south of the RCWRF facility as shown in Figure 3 below, and in fact, RCWRF effluent has never been dir ectly discharged to Drainage Ditch #4 (see Attachment 3, and Section 3.11.3, Contaminant Concentration Downgr adient of the RCWRF, of this support document for additional information regarding the RCWRF effluent outfall). Furthermore, no evidence could be found to document that the RCWRF has ever released mercury into Drainage Ditch #4. In fact, the discharge from the RCWRF does not contain mercury (see Attachment 1 to th is support document). Additi onally, aside from general allegations, Unimax did not present any data to show that mercury contamination is associated with the effluent from the RCWRF, nor did it provide evidence that the RCWRF has historically discharged effluent to Drainage Ditch #4, that could contribute to the sign ificant increase in the observed release sample.
Contrary to Unimax’s assertions, the HRS documentation r ecord at proposal does not conclude that the RCWRF is not contributing mercury contamination to Draina ge Ditch #4 because the RCWRF discharge is not being monitored; rather, the HRS documentation record at propo sal identifies the facility to be a potential off-site contributor. However, as discussed above and shown in Figure 3, the historical RCWRF discharge point is downgradient of the release sample location (MNOP-D4-W-09-SD, shown above in Figure 3 and in Figure 2 of this support document; also, see Reference 3 of the HRS documentation record at proposal for a topographical map) and thus it is unlikely that RCWRF discharge contribut ed to the mercury contamination levels in the release sample.Macon Naval Ordnance Plant NPL Listing Support DocumentMay201328Figure 3. Aerial image of the Rocky Creek Water Reclamation Facility indicating the location of the historical effluent outfalland theapproximate locations of PPE-1 and the observed release sample MNOP-D4-W-09-SD (see figure 2 for the exact sample locations).Macon Naval Ordnance Plant NPL Listing Support Document May 2013

Even if the RCWRF effluent had been discharged to Dr ainage Ditch #4, there is no evidence suggesting that mercury would have been present in the discharge. The RCWRF currently monitors its discharge for mercury as required by its NPDES permit and performs annual effluent testing with results dating back to 1996 (presented in Attachment 1 of this support document). The attached sampling results (Attachment 1) show that mercury has never been documented to be present in the effluent leaving the facility for this time period. Based on the information available at the time of the HRS evaluation, no evidence exists to suggest that the RCWRF effluent is a contributor to the mercury contamination found in the observed release sample in Drainage Ditch #4.
Insomuch as any mercury in the discharges from the GP and Southern Wood Piedmont Company would have to pass through the RCWRF, no indication of a release of mercury from the RCWRF to the wetlands east of Drainage Ditch #4 can be found (see section 3.11.3, Contaminant Concentration Downgradient of the RCWRF, of this support document for further explanation of the RCWRF treatment facility processes). Water discharges from GP and the Southern Wood Piedmont Company cannot be said to have contributed to the significant increase in the observed release. However, these properties may be considered at a later stage in the Superfund process.
For additional information, see section 3.11.3, Contaminant Concentration Downgradient of the RCWRF, of this support document, which addresses the concentration gradie nt in Drainage Ditch #4 as it relates to the RCWRF discharge
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.11.1.2 GP Air Emissions

Comment: Unimax commented that the GP released mercury to the air and that GP should be considered a possible source of the mercury contamination in the vicini ty of the Site. Unimax specifically commented that the mercury will settle out on nearby soils and plants. Unimax asserted that GP air emissions are also a plausible source of the low levels of mercury found in surface soils throughout the Site and in the background samples.
Response: Contamination originating from GP air emissions is not a likely source of the mercury either in Source 1 or in the observed Release sample in Drainage Ditc h #4. The HRS documentation record at proposal includes samples in the vicinity of the Site that show that wi despread mercury contaminati on is not present, as would be expected if significant dispersion of mercury resulting from air emissions.
If aerial deposition were the source of contamination at th e Site as Unimax asserts, the contamination would be widespread throughout the MNOP property. The HRS documentation record at proposal contains six soil and sediment samples from the July 2011 Supplemental Sampling Event that are located throughout the sampling area on the MNOP property and in Drainage Ditch #4 that do not indicate widespread mercury contamination (depicted in Figure 1 of this support document and Figu re 3 of the HRS documentation record at proposal). Additionally, the 2009 Region 4 SESD (performed by TetraTech) data (these data sets were identified by Unimax) are included as References 7, 34 and 35 of the HRS documentation record at proposal; and, as Unimax commented, only 6 of the 43 surface soil samples show de tectable mercury levels in the 2009 Region 4 SESD data. These findings support that merc ury is not ubiquitous or widespread throughout the MNOP property except for the mercury contamination as identified in the HR S documentation record at proposal as Source 1 near Building 109. Furthermore, Unimax presented no data to support that widespread mercury contamination on the MNOP property exists that woul d be consistent with aerial de positions from the GP facility.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

29Macon Naval Ordnance Plant NPL Listing Support Document May 2013

3.11.1.3 Contribution of Sources West and North of Source 1

Comment : Unimax asserted that the mercury contamination in the release sample in Drainage Ditch #4 did not come from MNOP or from contamination caused by MNOP . Unimax commented that the mercury contamination in the western portion of the MNOP property did not cause the mercury contamination in the release in Drainage Ditch #4 and that the contamination in the northern area of the MNOP property did not originate from MNOP. Unimax also commented that other data sets indicate th at mercury contamination may be present on the western portion of the MNOP property but Unimax concluded that the western portion of the property does not affect Drainage Ditch #4.
Response: Mercury contamination in the release sample has been documented to have originated from the MNOP site, not from sources west and north of Source 1. Mercury in the contaminated soils on the northern portion of the Site came from the MNOP facility (Source 1), not othe r off-site sources; this area of mercury contaminated soil, which drains to Drainage Ditch #4, is the only iden tified mercury source documented to enter Drainage Ditch #4. As discussed in section 3.9, Source 1, of this support document, multiple soil sample s collected throughout the MNOP property show that the mercury contamination in Source 1 is not originating from off-site sources, including those areas north or west of the Site.
Regarding the possible northern sources, as shown in Fi gure 1 of this support document, multiple soil samples were taken throughout the MNOP property in the June 2011 Supplemental Sampling Event. These samples include locations to the north (MNOP-02-SF) and west (MNOP-05-SF) of Source 1. These sample locations are south of the northern source area pointed to by the Un imax and are thus located between the northern area and both Source 1 and Drainage Ditch #4. These samples contain mercury at levels that are not detectible or below the concentration in the background sample (MNOP-01-SF) and show that contamination in Source 1 is not originating from off-site sources to the north or west of Source 1. If mercury contamination were reaching Source 1 from these areas, the mercury in samples from between the areas should be detectible and at similar levels as found in Source 1.
Regarding contamination in the western portion of the Site; while some mercury contamination may be present on the western portions of the MNOP property, the wester n portion of the MNOP property drains into Drainage Ditch #1 and does not impact the eastern portion of the MNOP property or Drainage Ditch #4. The HRS documentation record at proposal lists the western portion of the property as a possible source of contamination, but states that it does not drain to Drainage Ditch #4. Un imax agreed in their comments that the western portions of the property do not affect the cont amination found in Drainage Ditch #4.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.11.2 Contaminant Concentration Gradient in Drainage Ditch #4

Comment: Unimax challenged the attribution of mercury contamination to the MNOP by claiming the sampling in the intermittent ditch (Drainage Ditch #4) between the Site source and the observed release sample did not indicate the mercury migrated to the release sample vi a that route. Unimax and Cozen commented that the contaminant concentration gradient in Drainage Ditch #4 is not supportive of MNOP being the upgradient source of mercury contamination and provided the following comments:

• Unimax commented that “[t]he hypothesized trans port pathway [used in the HRS evaluation] through Drainage Ditch #4 is not supported by the data.”

• Unimax commented that the lowest mercury concentrations in sediment occur near the MNOP facility and in the upstream reaches of Rocky Creek.

30Macon Naval Ordnance Plant NPL Listing Support Document May 2013

• Unimax stated that the mercury concentrations in th e ditches on the MNOP property tend to decrease as they travel downgradient on the property.

• Cozen commented that the EPA background sediment sa mple is an order of magnitude higher than the sediment samples taken from Drainage Ditch #4 on MNOP property.

Unimax stated that the “EPA’s failure to consider th e concentration gradient, which reveals very low or non detectable levels of mercury in Ditch #4 at the southern site boundary and north of the RCWRF and the highest levels of mercury immediately downgr adient of the RCWRF, is arbitrar y and capricious.” Unimax commented that by plotting the mercury concentration gradient in Dr ainage Ditch #4 it becomes clear that the MNOP is not a “likely or material” contributor to the higher mercur y concentrations at and downgradient of the RCWRF. Further, the low mercury concentrations found in sedim ent samples in Drainage Ditch #4 on the MNOP property provide “evidence of no source of mercury upgradient of their locations.”
Response: The contaminant concentration gradient in Drainage Ditch #4 is supportive of an upgradient source of mercury contamination and the significant increase in mercury contamination found in the release sample (MNOP-D4-W-09-SD) is attributed to the Site. While the mercury concentration gradient is not at a constant concentration or a slowly decreasing concentration with distance from Source 1, this is most likely due to the streambed morphology.
As cited in section 3.11, Observed Release - Attribution , of this support document, the HRS requires that for an observed release by chemical analysis to be identified, at least part of the significant increase in a hazardous substance in a release sample be attributable to a rele ase from the site. The HRS documentation record at proposal on pages 25 and 26 establishes that at least some portion of the mercury contamination found in the release sample (MNOP-D4-W-09-SD) is due to the Site as addressed in section 3.11, Observed Release - Attribution , of this support document.
The contaminant concentration gradient observed in Drai nage Ditch #4 (presented in Figure 1 of this support document) is supportive of an upgradient source of merc ury on the MNOP property. The physical characteristics of the drainage ditch support the mercury contamination c oncentration gradient seen in the data presented in the HRS documentation record at proposal. These physical char acteristics include the intermittent nature and the streambed gradient of Drainage Ditch #4. These two characteristics explain how the data collected in the Ditch support contamination originating from the MNOP site source.
Drainage Ditch #4 is an intermittent stream as shown in Reference 3 of the HRS documentation record at proposal. In addition to having intermittent flow, the streambed gradient 4 of Drainage Ditch #4 from the MNOP property to PPE-1 5 in the palustrine forested wetland is appr oximately 75 ft/mile (gradient of 1.5%). The streambed gradient after PPE-1 (once the Ditch reaches the palustrine forested wetlands ) is less than 10 ft/mile (streambed gradient of 0.2%) (see Reference 3 of the HRS documentation record at proposal). 6 The streambed gradient suggests that water flowing in the ditch exhibits two different flow regimes. The first flow regime occurs in the water in the portion upgradient of PPE-1. The upper portion of Drainage Ditch #4 flows at a high velocity

4 Streambed gradient is calculated by dividing the change in elevation by the lateral distance covered. The gradient is then multiplied by 100 to attain a percent gradient. 5 PPE-1 is located along Drainage Ditch #4 at the point where th e ditch enters HRS-eligible wetlands (at this site, Palustrine forested wetlands) and does not correspond to a sample location. 6 This gradient value was calculated using the topographical ma p for the area presented in the HRS Documentation Record at proposal (Reference 3 of the HRS documentation record at proposal). The upstream portion of Drainage Ditch #4 drops 30 feet in elevation from the southern boundary of the MNOP property to PPE-1 (which is approximately 2000 ft. downgradient of the property). The downgradient portion, below PPE-1, does not show an elevation change on the topographical map within one mile of PPE-1, therefore an estimation of 10 feet was used as the elevation change could not be greater than 10 feet if it does not cross a topographical contour line.

31Macon Naval Ordnance Plant NPL Listing Support Document May 2013

(high streambed gradient) and carries water, and any cont amination, away from the MNOP facility with little to no deposition within Drainage Ditch #4. The second flow regime occurs as the wa ter enters the palustrine forested wetlands at PPE-1. The lower portion of Drainage Ditch #4, after the ditch enters the wetland, flows at a low velocity (lower streambed gradient) and is supportive of sediment (and contaminant) deposition.
The flow regime in the upper portions of Drainage Ditc h #4 (upgradient of PPE-1) retard the settling of particles (including those containing or associated with contam ination) in the ditch following precipitation events. The sediments and contamination in the water will travel at a higher velocity upgradient of PPE-1 and will have less time to settle (if at all) in this portion of the stre ambed of Drainage Ditch #4 where the upgradient sediment samples were taken. After the flow enters the palustrine forested wetlands (at PPE-1), the flow regime changes. The streambed gradient lowers to 0. 2% and the velocity of the water slows to allow for increased amounts of suspended sediments to settle out in the streambed of Drainage Ditch #4. This area is where samples MNOP-D4- W-08-SD and MNOP-D4-W-09-SD were taken.
Therefore, it is expected that upgradient streambed sediment samples in the area of the first, higher velocity flow regime would have lower contamination than sedimen t samples downgradient of PPE-1 as the contamination from Source 1 would have more time to settle into the sediment in the drainage ditch in the area of the second flow regime, which slows in the palustrine forested wetlands. Thus, the concentra tion gradient of mercury contamination observed in Drainage Ditc h #4 is supportive of an upgradient source of mercury consistent with the MNOP facility. The possibility of the mercury originati ng from other possible facility sources is discussed further in Section 3.11.1, Possible Mercury Releases from Alternative Sites , of this support document.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.11.3 Contaminant Concentration Downgradient of the RCWRF

Comment: Unimax argued that because the concentration of mercury is higher downstream of the RCWRF facility, the source of the mercury was not Source 1 at the Site. Unimax commented that the highest mercury concentrations occur downgradient of the RCWRF dischar ge, suggesting that the source of the mercury in the release samples is the discharge from the RCWRF. Unimax stated that the “EPA’s failure to consider the concentration gradient, which reveals very low or nondetectab le levels of mercury in Ditc h #4 at the southern site boundary and north of the RCWRF and the highest levels of mercury immediately downgradient of the RCWRF, is arbitrary and capricious.” Unimax further commented that the attribution of an observed release to the former MNOP is not supported by the data; instead, the data indicate the RCWRF and its industrial user, GP, as the responsible parties for the mercury c ontamination found in the observed release sample. Unimax asserted that the RCWRF has historically received mercury-containing w astewater from the GP facility and other industrial facilities.
Response: The significant increase in mercury concentration in Drainage Ditch #4 downgradient of the RCWRF location (i.e., the increased concentration gradient) was correctly attributed to the MNOP site and not to discharges from the RCWRF. While the concentration of mercury in Drainage Ditch #4 is higher in a sample downgradient of the RCWRF facility location, as explai ned in section 3.11.1, Possi ble Mercury Releases from Alternative Sites, of this support document, the location of the sample used to establish an observed release is upgradient of the location of the historical discharge outfall from the RCWRF. Furthermore, the RCWRF discharge does not contain mercury. Therefore disch arge from the RCWRF is not likely the cause of the significant increase in mercury contamination in the observed release sample (see Section 3.11.1.1, Wastewater Discharges from GP and SWPC via the RCWRF, of this support document).
Based on information collected in responding to this comment (see Attachment 1 and Figure 3 of this support document), the discharge from this wastewater treatmen t facility contained no mercury and the historical outfall

32Macon Naval Ordnance Plant NPL Listing Support Document May 2013

from the RCWRF was discharged directly into the wetland south of the treatment facility and not to Drainage Ditch #4; Unimax did not identify any informati on documenting releases of mercury from the RCWRF.
As described in 3.11.2, Contaminant C oncentration Gradient in Drainage Ditch #4, of this support docum ent, the possible causes of the contaminant concentration gradie nt in Drainage Ditch #4 were evaluated and it was determined that the gradient is c onsistent with an upgradient source such as Source 1 on the MNOP property. Potential mercury discharges from the RCWRF were cons idered when establishing attribution of the mercury release to the Site. No evid ence was identified (nor did the commenters present any evidence) to suggest that the RCWRF ever discharged mercury into Drainage Ditch #4 (see section 3.11.1.1, Wastewater Discharges from GP and the Southern Wood Piedmont Company via the RCWRF, of this support document).
Pages 25 and 26 of the HRS documentation record at propo sal discuss the attribution of mercury contamination found at the Site and considered the RCWRF as a potential contributor to the contamination in Drainage Ditch #4 as follows:
Possible off-site sources also include the FMNOL, AWI, and the Rocky Creek water reclamation facility (RC WRF). AWI and FMNOL are currently listed on the EPA NPL under CERCLIS ID No. GAN000410033 at docket number EPA- HQ-SFUND-2010-0640-0002 (Ref. 47). Runoff from FMNOL and AWI flows into Rocky Creek via a drainage easement. The drainage easement enters Rocky Creek west and upstream of Source No. 1 soil sample MNOP-04-SF and Drainage Ditch 4. Drainage Ditch 4 is located just west of the RC WRF (Ref. 7, Appendix A, p. A-2).

... The RC WRF, located southeast of and downstream from MNOP, provides wastewater treatment for the southern and western portions of the City of Macon. Treated wastewater from this facility is discharged into the Ocmulgee River; how ever, RC WRF maintains a National Pollutant Discharge Elimination System (NPDES)-permitted discharge point at the southern property boundary (Refs. 9, p. 3; 45, pp. 2, 3; 46, pp. 1, 8). The NPDES permit requires RC WRF to monitor outfall discharges for biochemical oxygen demand, total suspended solids, pH, chlorine, fecal coliform, nitrogen, dissolved oxygen, PCBs, and phosphorus (Ref. 46, pp. 6, 7). There are currently no documented releases of mercury at th is location (Refs. 9, p. 3; 46, pp. 6, 7).
The RCWRF was built as a joint treatment facility with the Macon Kraft Company, now called GP, and provides wastewater treatment for the GP facility. Mercury may be a possible constituent in the waste water from GP that is discharged to the RCWRF for treatment. While the RCWRF may have received mercury-containing waste water from GP, the RCWRF was designed to treat effluent delivered to the facility. The RCWRF plant is an advanced secondary wastewater treatment facility that includes activated sludge aeration basins, clarifiers, conventional filtration, as well as disinfectants before its effluent is discharged into the Ocmulgee River ( http://maconwater.org/water-reclamation-facilities ). As shown in Attachment 2 to this support document, mercury is one of the metals known to be captured by the extended aeration activated sludge process and is found in the biosolids 7 that are removed from the wastewater. These pro cesses combined effectively treat the mercury in the effluent, and there has been no documented mercury in the discharge from the RCWRF.
The RCWRF historically discharged to the wetlands east of Drainage Ditch #4 from th e time it began operation in 1971 to the mid 1980’s when the discharge was re-routed to the Ocmulgee River. The RCWRF currently discharges to the Ocmulgee River which is approximately 2 miles east of the facility (see Reference 3 of the HRS

7 Biosolids is a term used to describe municipal treatment plant solids that result from the treatment of wastewater. Biosolids are processed wastewater solids that have met specific criteria and are suitable for land application. Specifically, the RCWRF biosolids have been tested for mercury, and the results are presented in Attachment 2 of this support document.

33Macon Naval Ordnance Plant NPL Listing Support Document May 2013

documentation record at proposal). Although the RCWRF has discharged effluent to the wetlands east of Drainage Ditch #4, no evidence or data supports a release of mercury from the RCWRF facility. Attachment 1 of this support document presents annual monitoring data (which dates back to 1996) for the effluent of the RCWRF and shows no mercury in the facility effluent. While th e discharge point for the RCWRF has been repositioned, no information was found or was presented by the commenter, to indicate that the conditions at the RCWRF significantly changed. The treatment system at the RCWR F is essentially the same as before 1996 and there is no evidence to suggest that discharge prior to 1996 might c ontain mercury. Therefore, no evidence suggests that the RCWRF effluent is a contributor to th e mercury contamination found in the release sample in Drainage Ditch #4
For additional information, see section 3.11.1, Wastewat er Discharges from GP and the Southern Wood Piedmont Company via the RCWRF, which addresses the possible contaminant contributions of GP and SWPC via the RCWRF.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.

3.11.4 Other Data Sets

Comment : Unimax commented that a large volume of “spatially extensive, high-quality, relevant data” has been ignored and stated that “[t]he HRS documentation record shows an arbitrary selectivity in use of the data.” Unimax asserted that the failure to present or analyze these data is a fundamental mistake because they help to explain the Site conditions. Unimax stated that “[E]PA guidance recommends using existing analytical data when they are of sufficient quality.”
Unimax commented that the HRS documentation record only obtained a small set of data focused around Building 109 and Drainage Ditch #4 and only used these data samples to show mercury contamination at the facility even though previous investig ations found “no significantly elevated mercury concentrations.” Unimax stated that the “EPA’s failure to attempt to explain this contradictory data is arbitrary and capricious.”
Unimax commented that both Rust and TetraTech obtained usable mercury measurem ents of more than 100 surface soil and sediment samples and found that low leve ls of mercury are pervasive in surface soils throughout the area and are not unique to the MNOP facility. Unimax further stated that “[t]hese data present a convincing picture of the absence of any material source of mercury to Drainage Ditch #4.” Unimax asserted that these additional data sets contradict the establishment of a source of mercury on the MNOP facility.

Unimax concluded that these other data sets show that mercury contamination on the MNOP facility cannot be contributing to the contamination in the observed re lease sample downgradient in Drainage Ditch #4.
Response : The June 2011 Supplemental Sampling Event provide d sufficient analytical data to document and attribute the significant increase in mercury contaminati on in the observed release to migration from Source 1 on the MNOP property, and best represents the current Site conditions. While the other data sets were not used for scoring purposes in the HRS evaluation, these other data sets were made available as references in the HRS documentation record at proposal and show mercury contamination that is consistent with the sampling results in the June 2011 Supplemental Sampling Event.
The HRS documentation record at proposal did not fail to present or analyze additional available data; rather, the HRS documentation record at proposal included the additiona l data referred to by Unimax (see References 7, 12, 13, 14, 21, 34 and 35 of the HRS documentation record at proposal) which support the findings in the June 2011 Supplemental Sampling Event data. The HRS documentation r ecord at proposal lists and provides references that contain the results of six other investigations that were performed at the Site prior to the June 2011 Supplemental Sampling Event. Table 1 on pages 13 and 14 of the HR S documentation record at proposal summarizes these previous investigations:

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TABLE 1: Summary of Previous Investigations
Company/

Agency Investigation Date Samples Collected Hazardous Substances

Detected References

Beaver Engineering Environmental Assessment 1989 Soil Metals 13, p. 3

Environmental Science and Engineering Confirmation Study of the Former Macon Naval Ordnance Plant 1990 Soil, ground water, and sediment Arsenic Cadmium Chromium Lead TCE 14, pp. I, 2-1, 3- 4, 3-6, 3-9, 3- 11, 4-2, 4-3, 4- 11, 4-12

USACE, Savannah District Site Investigation 1996 Soil, ground water, surface water, and sediment Cadmium Chromium Lead Mercury 13, pp. vi, 1, 13, 20, 27, 28, 55 through 60, 63, 71 through 92, 94 through 104, 106, 107 USACE, Savannah District Hazardous Site Response Act (HSRA) Compliance Status Report 1998 to 2000 Soil, ground water, surface water, and sediment Arsenic Cadmium Chromium Lead Zinc TCE PCE Benzo(a)pyrene 12, pp. i, ii,1-1, 1-10, 2-9, 2-19, 2-33, Appendix O, pp. O15 through O53

USACE, Savannah District Post-Test Groundwater Sampling 2004 Ground water DCE TCE PCE Vinyl Chloride 21, pp. 1, 2, 5, 11

EPA Expanded Site Inspection May 2009 Soil, ground water, surface water, and sediment Cadmium Chromium Copper Lead Manganese Mercury Nickel PCBs Pesticides SVOCs VOCs 7, pp. 1, 6, 7, Appendix B, pp.B-12 through B69, B-71 through B-75,B-77 through B113

EPA Supplemental Sampling Event June 2011 Soil and sediment Mercury 9, pp. 1, 3; 11, pp. 5, 8, 19, 21
The HRS documentation record did not fail to present or analyze additional data sets available for the Site. Rather, in June 2011 a supplemental sampling event was completed and included samples located on the MNOP property and in Drainage Ditch #4. Th e HRS documentation record at proposal scored the Site on this June 2011 Supplemental Sampling Event because it is the most current da ta that is available for the Site. As presented in the HRS documentation record at proposal , the June 2011 Supplemental Samp ling Event included multiple surface soil samples and sediment samples located in Drainage Ditch #4 (see Figure 1). These samples, as presented in

35Macon Naval Ordnance Plant NPL Listing Support Document May 2013

the HRS documentation record at proposal, provide sufficien t data to score the Site as discussed in this support document in sections 3.9, Source 1; 3.10, Observed Release – Background; and 3.11, Observed Release – Attribution.
The additional data sets noted by the commenter do not c ontradict the establishment of Source 1 or the observed release of mercury in Drainage Ditch #4. These additiona l data sets do support Unimax’s assertion that mercury contamination is not ubiquitous throughout the property, however, it is not true that there are no “elevated mercury concentrations” identified in these data sets. Fo r example, in the 2009 Expanded Site Assessment alone, mercury is not detected in the background sample loca ted on the north east portion of the MNOP property and at least two soil samples located near Bu ilding 109 are detected at concentrations above the sample quantitation limit as required by the HRS and explained in section 3.9, Source 1, of this support document.
The contamination found in the June 2011 Supplemental Sampling Event is supported by the additional data sets that the commenters mention and are provided as references to the HRS documentation record at proposal as shown in Table 1 above. However, the June 2011 data set is sufficient to document attribution, at least in part, to Source 1 on the MNOP property.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.



### 3.12 Characteriz ation of PPE 1

Comment : Unimax commented that PPE 1 is located within a settling basin of the RCWRF in which the National Wetlands Inventory (NWI) characterizes the location as Em ergent Wetland “PEM1Fx”. Unimax asserts that this is a man-made, or excavated basin or channel and accordi ng to topographic quadrangle ma ps this area is depicted as part of the RCWRF.
Response : The HRS documentation record at proposal correctly identifies the probable point of entry to Drainage Ditch #4 from Source 1 (see Figure 2). PPE-1 was identified at the point at which Drainage Ditch #4 intersects an eligible surface water body; specifically, the eligible surface water body at this site is the HRS eligible wetland: Freshwater Palustrine Forested/Shrub Wetland (see Figur e 1 of this support document). The HRS documentation record at proposal does not identify PPE-1 as being located within a settling basin of the RCWRF labeled an emergent wetland “PEM1Fx.”
HRS Section 4.0.2, Surface water categories , defines what is considered a surface water body for HRS purposes as follows:
For HRS purposes, classify surface water into four categories: rivers, lakes, oceans, and coastal tidal waters.

-Rivers include:

...

• Perennially flowing waters fro m point of origin to the ocean or to coastal tidal waters, whichever comes first, and wetla nds contiguous to these flowing waters.
HRS Section 4.1, Overland/flood migration component , establishes how to identify a probable point of entry for a source. It states to “[u]se the overland/flood migration component to evaluate surface water threats that result from overland migration of hazardous substances from a source at the site to surface water.”
Page 21 of the HRS documentation re cord at proposal explains the establishment of PPE 1, stating:

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37 The hazardous substance migration pathway includ es both the overland segment and the in-water segment that hazardous substances would take as they migrate away from sources. The overland segment begins at the source and proceeds downgrad ient to the probable point of entry (PPE) to surface water. The in-water segment at the PPE conti nues in the direction of flow (Ref. 1, Section 4.1.1.1).
Overland flow from Source No. 1 (contaminated soil in the eastern portion of the MNOP property) is directed to Drainage Ditch 4. Drai nage Ditch 4 is an intermittent drainage route located upgradient of the PPE along the eastern bound ary of the MNOP property (Ref. 9, pp. 1, 3). Surface water runoff from Source No. 1 flows overland about 625 feet and enters Drainage Ditch 4. Drainage Ditch 4 flows south for about 3,250 feet and enters HRS-eligible palustrine forested wetlands adjacent to Rocky Creek. The point where Drainage Ditch 4 enters the palustrine forested wetlands is PPE 1. Drainage D itch 4 continues south within palustrine forested wetlands for about 1,250 feet and enters Rocky Creek (Refs. 3; 36, Map 1) (also see Figure 3 of this HRS documentation record).
The HRS documentation record at proposal establis hes PPE-1 as the point at which hazardous substances migrating overland via runoff enter an eligible surface water body. The HRS documentation record at proposal does not identify PPE-1 as being located within a historical settling basin of the RCWRF, rather, as shown in Figure 2 of this support document, PPE-1 is identified at sample location MNOP-D4-W-08-SD, which is the entry point of surface runoff in Drainage Ditch #4 to Palustri ne Forested, Broad-Leaved Deciduous, Seasonally Flooded wetland. As identified by HRS Section 4.0.2, Surface water categories , HRS-eligible wetlands contiguous to flowing waters are considered surface water; therefore, PPE-1 is correctly established at this intersection in Drainage Ditch #4 where overland flow en ters palustrine forested wetlands.
This comment results in no change to the HRS score and no change in the decision to place the Site on the NPL.


## 4. Conclusion

The original HRS score for this site was 48.97. Based on the above responses to comments, the Site score remains unchanged. The final scores for the MNOP site are:

Ground Water Not Scored Surface Water 97.94 Soil Exposure Not Scored Air Not Scored HRS Site Score 48.97

# Attachment 1: Macon Water Authority, Rocky Creek Effluent Sample Results, Various Dates_____ 

### Client Sample Results
Client: Macon Water Authority ProjecUSite: Rocky Creek Effluent Annual PP Scan



## ________ ,_.,

'lient Sample ID: AA32930 Ro cky Creek Effluent P re-CI2 TestAmerica Job ID: 680-75245-2

-----
....... 

## _ Lab Sample ID: 680-75245-3

.... ate Collected: 12/13/11 00:00 Date Received: 12/14/11 09:43 Matrix: Water

Method: 200.8 ·Metals (ICP/MS) Analyte Antimony Arsenic Beryllium Cadmium Chromium Copper Lead Nickel Selenium Silver Thallium
Zinc Result
<0.0050
<0.0050
<0.0010
<0.00070
<0.0050
<0.0050
<0.0010
<0.0050
<0.0050
<0.0050
<0.0010

0.042 Qualifier RL
0.0050
0.0050
0.0010
0.00070
0.0050
0.0050
0.0010
0.0050
0.0050
0.0050
0.0010 0.010 MDL Unit mg/l mgll mg/L mgll mgll mg/L mg/L mg/l mg/L mg/L mg/L mg/L D Prepared
12/15/1111:06
12/15/1111:06
12/15/1111:06
1211511111:06
12/15/1111:06
12/1511111:06
12/15!1111:06
12/15/1111:06
12/15/1111:06
1211511111:06
1211511111:06 12/15/1111:06 Analyzed
12115/1117:37
12/15/1117:37
12115/11 17:37
12/15/1117:37
12/15/1117:37
12/15/1117:37
12/15/1117:37
12/15/1117:37
12/15/1117:37
12/15/1117:37
12/15/1117:37
12/15/1117:37 Oil Fac
1

# ~

[Method: 245.1 ·Mercury (CVAA)

Analyte Mercury Result <0.00050 Qualifier RL 0,00050 MDL Unit mg/L D Prepared 12/16/1110:19 Analyzed 12/19/1116:01 Oil Fac

TestAmerica Savannah Page 6 of 29 12/23/2011Analytical Data

Client: Macon Water Authority Job Number: 680-65488-1

Client Sample ID: AA27826 -Rocky Creek EFF

Lab Sample ID: 680-65488-1 Dale Sampled: 02108/2011 0000 Client Matrix: Water Dale Received: 02109/2011 0930

200.8 Metals (ICPIMS)

Method: 200.8 Analysis Balch: 680-194263 Instrument ID: ICPMSB Preparation: 200.8 Prep Batch: 680-194066 Lab File ID: 194066.chr Dilution: 1.0 Initial WeightNolume: 50 mL Date Analyzed: 0211112011 1549 Final WeighWolume: 250 mL Date Prepared: 02/10/2011 1200

Analyte Result (mg/L) Qualifier RL Antimony <0.0050 0.0050 Arsenic <0.0050 0.0050 Beryllium <0.0010 0.0010 Cadmium <0.00070 0.00070 Chromium <0.0050 0.0050 Copper <0.0050 0.0050 Lead <0.0010 0.0010 Nickel <0.0050 0.0050 Selenium <0.0050 0.0050 Silver <0.0050 0.0050 Thallium <0.0010 0.0010 Zinc 0.030 0.010

245.1 Mercury (CVAA)

Method: 245.1 Analysis Balch: 680-194712 Instrument ID: LEEMAN! Preparatlon: 245.1 Prep Balch: 680-194192 Lab File ID: 021611.chr Dilution: 1.0 Initial WeighWolume: 50 ml Date Analyzed: 0211612011 1308 Final WeighWolume: 50 ml Date Prepared: 02111/2011 1051

Analyte Result (mg/L) Qualifier RL Mercury <0.00050 0.00050

TestAmerlca Savannah Page 5 of 10 02/17/2011Analytical Data

Client: Macon Water Authority Job Number: 680-44771-2

Client Sample 10: AA16048

Lab Sample ID: 680-44771-3 Dale Sampled: 02/15/2009 0000 Client Matrix: Water Date Received: 02/1712009 0902

200.8 Metals (ICP/MS)

Method: 200.8 Analysis Batch: 680-130762 Preparation: 200.8 Prep Batch: 680-130575 Dilution: 1.0 Date Analyzed: 02/1912009 2141 Date Prepared: 02/19/2009 1116

Analyte Result (mg/L) Antimony <0.0050 Arsenic <0.0050 Beryllium <0.0010 Cadmium <0.00070 Chromium <0.0050 Copper 0.0060 Lead <0.0010 Nickel <0.0050 Selenium <0.0050 Silver <0.0050 Thallium <0.0010 Zinc 0.023 Instrument 10: ICPMS-A Lab File ID: NIA Initial WeighWolume: 50 mL Final WeighWolume: 250 mL

Qualifier RL

0.0050 0.0050 0.0010 0.00070 0.0050 0.0050 0.0010 0.0050 0.0050 0.0050 0.0010 0.010

Method: 245.1 Preparation: 245.1 Dilution: 1.0 Date Analyzed: 02/1912009 1532 Date Prepared: 02118/2009 1208

Analyte Mercury 245.1 Mercury (CVAA)
Analysis Batch:**680~130779** Prep Batch: 680-130453

Result (mg/L)

<0.00050 Instrument ID: Lab File ID: Initial WeighWolume: Final WeighWolume:

Qualifier LEEMAN1 NIA 50 mL 50 mL

RL

0.00050

TestAmerica Savannah Page 11 of 30

### Analytical Data

Client: Macon Water Authority Job Number: 680-54888-2

Client Sample ID: Rocky Creek Pre-Chlorinated Effluent (AA21742)

Lab Sample ID: 680-54888-3 Date Sampled: 02/07/2010 0000 Client Matrix: Water Date Received: 02/09/2010 1114

200.8 Metals (ICP/MS)

Method: 200.8 Analysis Batch: 680-160823 Instrument ID: ICPMSB Preparation: 200.8 Prep Batch: 680-160403 Lab File ID: N/A Dilution: 1.0 Initial WeighWolume: 50 mL Date Analyzed: 02/13/2010 0618 Final WeighWolume: 250 mL Date Prepared: 02/10/2010 1122

Analyte Result (mg/L) Qualifier RL ,-----­ 

### Ari'tlnlO-ny-

--**------~** 

## <o:oo55 0.0050 Arsenic <0.0050 0.0050 Cadmium <0.00070 0.00070 Chromium <0.0050 0.0050 Copper 0.019 0.0050 Lead 0.0012 0.0010 Nickel <0.0050 0.0050 Selenium <0.0050 0.0050 Silver <0.0050 0.0050 Thallium <0.0010 0.0010 Zinc 0.042 0.010

Method: 200.8 Analysis Batch: 680-160824 Instrument ID: ICPMSB Preparation: 200.8 Prep Batch: 680-160403 Lab File ID: N/A Dilution: 1.0 Initial WeighWolume: 50 mL Date Analyzed: 02/13/2010 0618 Final WeighWolume: 250 mL Date Prepared: 02/10/2010 1122

Result (mg/L) Qualifier 

## ···· ... ·-····· -·<a:ao10"

______**------------------~**

245.1 Mercury (CVAA)

Method: 245.1 Analysis Batch: 680-160775 Instrument ID: LEEMAN1 Preparation: 245.1 Prep Batch: 680-160393 Lab File ID: N/A Dilution: 1.0 Initial WeighWolume: 50 mL Date Analyzed: 02/11/2010 1526 Final WeighWolume: 50 mL Date Prepared: 02/10/2010 1052

Analyte 

### Mercuiy Result (mg/L) 

### <6.1lolls6 Qualifier RL 

## o:aoo51l

04/05/2010 TestAmerica Savannah Page 13 of 33

### ANALYTICAL 

## = RJLJ C E S. I N C . Environmental Monitoring & Laboratory Analysis 

# IA31I

110 Technology Parkway Norcross, GA 30092 (770) 734-4200 FAX (770) 734-4201


### laboratory Report

Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Mark WyzaJek February 5, 2008 Report No. 254514-2 Macon Water Authority Sample Description: Wastewafer. Composite, Rocky Creek PPL-GA 129, Rocky Creek Effluent, 01/24/2008, 00:00, received 01/25/2008

Report. Analytical Preparation Oil. Results Preparation Analytical Analyte Result Limit Units Qual. Method Method Factor CAS# Source 10 Batch# Date Time Date Time !nit.

129 Priority**Pollutants~** Georgia

General Chemistry
Total Phosphorus (P) 0.37 0.02 mg/L SM 4500-P B.E SM 4500-P B.E 1 7723-14-0 254514-2 148966 1/28/08 1130 1/29/08 1400 YM

Inorganic Anions

Nitrate-Nitrite Nitrogen (N) 4.9 0.1 mg/L EPA300.0 1 E-10128 254514-2 149166 2/1/08 1346 LMH

Metals
Total Antimony (Sb) ND 5 ug/L EPA200.8 EPA 200.8 1 7440-36-0 254514-2 148689 1/28/08 0840 1/28/08 1829 CKE Total Arsenic (As) ND 5 ug/L EPA200.8 EPA200.8 1 7440-38-2 254514-2 148689 1/28/08 0840 1/28/08 1829 CKE Total Beryllium (Be) ND 1 ug/L EPA200.8 EPA 200.8 1 7440-41-7 254514-2 148689 1/28108 0840 1/28/08 1829 CKE Total Cadmium (Cd) ND 0.7 ug!L EPA200.8 EPA200.8 1 7440-43-9 254514-2 148689 1/28/08 0840 1/28/08 1829 CKE Total Chromium (Cr) ND 5 ug/L EPA200.8 EPA200.8 1 7440-47-3 254514-2 148689 1/28/08 0840 1/28/08 1829 CKE Total Copper (Cu) 6 5 ug/L EPA200.8 EPA200.8 1 7440-50-8 254514-2 148689 1/28/08 0840 1/28108 1829 CKE Total Lead (Pb) ND 1 ug!L EPA200.8 EPA200.8 1 7439-92-1 254514-2 148689 1/28/08 0840 1/28108 1829 CKE Total Mercury (Hg) ND 0.5 ug/L EPA 245.1 EPA245.1 1 7439-97-6 254514-2 148917 1/29/08 0940 1/29/08 1650 csw Total Nickel (Ni) ND 5 ug/L EPA200.8 EPA200.8 1 7440-02-0 254514-2 148689 1/28/08 0840 1/28108 1829 CKE Total Selenium (Se) ND 5 ug/L EPA 200.8 EPA200.8 1 7782-49-2 254514-2 148689 1/28/08 0840 1/28/08 1829 CKE Total Silver (Ag) ND 5 ug/L EPA200.8 EPA200.8 1 7440-22-4 254514-2 148689 1/28/08 0840 1/28108 1829 CKE Total Thallium (TI) ND 1 ug/L EPA200.8 EPA200.8 1 7440-28-0 254514-2 148689 1/28108 0840 1/28/08 1829 CKE Total Zinc (Zn) 19 10 ug!L EPA200.8 EPA200.8 1 7440-66-6 254514-2 148689 1/28/08 0840 1/28/08 1829 CKE

Paae 1 of 1

## ANALYUCAL E R_V I C E S. I N C .
Environmental Monitoring & Laboratory Analysis

# IJ~stl 110 Technology Parkway Norcross, GA30092 (770) 734-4200 FAX (770) 734-4201 

### laboratory Report

Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek July 18. 2006 Report No. 230497-1 Macon Water Authority Sample Description: Wastewater, Composite, Rocky Creek PPL, RC Effluent, 06/28-06/29/2006, 00:00- 00:00, received 06/30/2006

Report. Analytical Preparation Oil. Results Preparation Analytical Analyte Result Limit Units Qual. Method Method Factor CAS# Source ID Batch# Date Time Date Time I nit.

129 Priority Pollutants- Georgia

General Chemistry
Total Cyanide (CN) Total Phosphorus (P) NO
0.56 20 0.02 ug/L mg/L EPA335.2 SM 4500-P B ,E EPA335.2 SM 4500-P B,E 1 1 57-12-5 7723-14-0 230497-1 230497-1 130401 130429 7/3/06 7/5/06 1830 1800 7/5/06 7/6/06 1845 2330 OMB OMB

Inorganic Anions

Nitrate-Nitrite Nitrogen (N) 2.7 0.1 mg/L EPA300.0 1 E-10128 230497-1 130469 7/4/06 0800 HE

Metals
Total Antimony (Sb) NO 5 ug/L EPA200.8 EPA200.8 1 7440-36-0 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Arsenic (As) NO 5 ug/L EPA200.8 EPA200.8 1 7440-38-2 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Beryllium (Be) NO 1 ug/L EPA200.8 EPA200.8 1 7440-41-7 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Cadmium (Cd) NO 0.7 ug/L EPA200.8 EPA200.8 1 7440-43-9 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Chromium (Cr) NO 5 ug/L EPA200.8 EPA200.8 1 7440-47-3 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Copper (Cu) 6 5 ugll EPA200.8 EPA200.8 1 7440-50-8 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Lead (Pb) ND 1 ug/L EPA200.8 EPA200.8 1 7439-92-1 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Mercury (Hg) NO 0.5 ug/L EPA245.1 EPA245.1 1 7439-97-6 230497-1 129730 713106 0535 7/3/06 1534 MCJ Total Nickel (Ni) NO 5 ugll EPA200.8 EPA200.8 1 7440-02-0 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Selenium (Se) NO 5 ug/L EPA200.8 EPA200.8 1 7782-49-2 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Silver (Ag) ND 5 ug/L EPA200.8 EPA200.8 1 7440-22-4 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Thallium (TI) NO 1 ug/L EPA200.8 EPA200.8 1 7440-28-0 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ Total Zinc (Zn) 33 10 ug/L EPA200.8 EPA200.8 1 7440-66-6 230497-1 130298 7/3/06 0625 7/5/06 1902 MCJ

D

............. -I

.... &-<

# I AA 

# s 

# II A N A L 

# y T I 

# c A L 

# s E R 

# v I 

# G E 

# s, I N 

# c**--------~E~n~vi~ro~n~1n~e~n~t~a~IM~o~n~ito-r~in~g-&~L-a~bo_r_a~to-~~A-n~a~ly-s~is** 

# ______ ___ 110 Technology Parkway Norcross, GA 30092 (770) 734-4200 FAX (770) 734-4201 

## Laboratory Report Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek Report No. 224948-1 March 8, 2006 Sample Description Macon Water Authority Wastewater, Composite, Rocky Creek PPL, RC Effluent, 02/22-02/23/2006, 06:5(-06:57, received 02/24/2006

Analytical Methoct. Analyte

_ Resl!lt Detection. Umit Units

129 Priority Pollutants- Georgia

General Chemistry EPA 335.2 Total Cyanide (CN) BDL 20 ug/L SM 4500-P B,E Total Phosphorus (P) 1.3

. 0.2 mg/L
Inorganic Anions EPA300.0 Nitrate-Nitrit.e Nitrogen (N) 4.1 0.1 mg/L

Metals EPA200.8 Total Antimony (Sb) BDL 5 ug/L EPA200.8 Total Arsenic (As) BDL 5 ug/L EPA200.8 Total Beryllium (Be) BDL 1 ug/L EPA200.8 Total Cadmium (Cd) BDL 0.7 ug/L EPA200.8 Total Chromium (Cr) BDL 5 ug/L EPA200.8 Total Copper (Cu) 6 5 ug/L EPA 200.8 Total Lead (Pb) BDL 1 ug/L EPA 245.1 Total Mercury (Hg) BDL 0.5 ug/L EPA200.8 Total Nickel (Ni) BDL 5 ug/L EPA200.8 Total Selenium (Se) BDL 5 ug/L EPA200.8 Total Silver (Ag) BDL 5 ug/L EPA 200.8 Total Thallium (TI) BDL 1 ug/L EPA 200.8 Total Zinc (Zn) 33 10 ug/L

SOL

- Below Detection Limit Page 1 of 1

# A N A L Y T I C A L S E R V I C E S, I N C 

# Sl Environmental Monitoring 

## & Laboratory Analysis 110 Technology Parkway Norcross, GA 30092 (770) 734-4200 FAX (770) 734-4201 

## Laboratory Report
Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Marl< Wyzalek Report No

.. 219930·1 November 14, 2005 Sample Description Macon Water Authority Wastewater, Composite, Rocky Creek PPL, RC Effluent, 11/01-11/02/2005, 06:00- 06:00, received 11/03/2005

Analytical Method Analyte Result Detection Limit Units

Priority Pollutant Metals

Metals EPA200.7 Total Antimony (Sb) BDL 0.005 mg/L EPA200.8 Total Arsenic (As) BDL 0.005 mg/L EPA200.7 Total Beryllium (Be) BDL 0.001 mg/L EPA200.8 Total Cadmium (Cd) BDL 0.0007 mg/L EPA200.7 Total Chromium (Cr) BDL 0.005 mg/L EPA200.7 Total Copper (Cu) 0.006 0.005 mg/L EPA200.8 Total Lead (Pb) 0.001 0.001 mg/L EPA245.1 Total Mercury (Hg) BDL 0.0005 mg/L EPA200.7 Total Nickel (Ni) · BDL 0.005 mg/L EPA200.8 Total Selenium (Se) BDL 0.005 mg/L EPA200.7 Total Silver (Ag) BDL 0.005 mg/L EPA200.8 Total Thallium (TI) BDL 0.001 mg/L EPA200.7 Total Zinc (Zn) 0.04 0.01 mg/L

BDL

- Below Detection Limit Page 1 of 1

# As~ 

# A N A l 

# y T I 

# c A l 

# s E R 

# v , c E 

# s, I N 

# c . I**~~~~~E~n~v~ir~o~n~m~e-n~ta~I~M~o-n~ito~r in-g~&~L~a~b~o~ra~t~o~ry~A-n~a~ly-s~is~~~~~**  1 1 

### 110 Technology Parkway Norcross, GA 30092 (770) 734-4200 FAX (770) 734-4201 

## Laboratory Report
Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek Report No. 206502-3 January 27, 2005 Sample Description Macon Water Authority Wastewater, Composite, PPL GA 129, Rocky Creek Effluent, 01/11-01/12/2005, 11:50, received 01/13/2005

Analytical Method

EPA 200.7 EPA206.2 EPA 200.7 EPA 213.2 EPA200.7 EPA 200.7 EPA239.2 EPA 245.1 EPA200.7 EPA270.2 EPA 200.7 EPA279.2 EPA200.7 Analyte Result Detection Limit Units

Metals Total Antimony (Sb) Total Arsenic (As) Total Beryllium (Be) Total Cadmium (Cd) Total Chromium (Cr) Total Copper (Cu) Total Lead (Pb) Total Mercury (Hg) Total Nickel (Ni) Total Selenium (Se) Total Silver (Ag) Total Thallium (TI) Total Zinc (Zn) 129 Priority Pollutants -Georgia

BDL 5 BDL 5 BDL 1 BDL 0.7 BDL 5 BDL 5 BDL 1 BDL 0.5 BDL 5 BDL 5 BDL 5 BDL 1 29 10 ug/L ug/L ug/L ug/L ug/L ug/L ug/L ug/l ug/L ug/L ug/L ug/L ug/L

BDL- Below Detection Limit Page 1 of 1

# A N A L Y T I C A L S E R V I C E S, I N C . 

# Sl Environmental Monitoring & Laboratory Analysis 110 Technology Parkway Norcross, GA 30092 {770) 734-4200 FAX (770) 734-4201 

## Laboratory Report
Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek Report No. 188691·1 February 3, 2004 Sample Description Macon Water Aulhority Wastewaler, Composile, PPL GA 129, Rocky Creek Effluent, 01/20-01/21/2004, 13:02, received 01/22/2004

Analytical Method Analyte Result Detection Limit Units

EPA 200.7 EPA206.2 EPA200.7 EPA 213.2 EPA 200.7 EPA200.7 EPA239.2 EPA 245.1 EPA200.7 EPA270.2 EPA200.7 EPA279.2 EPA200.7 Metals Total Antimony {Sb) Total Arsenic {As) Total Beryllium (Be) Total Cadmium {Cd) Total Chromium {Cr) Total Copper (Cu) Total Lead {Pb) Total Mercury (Hg) Total Nickel (Ni) Total Selenium (Se) Total Silver (Ag) Total Thallium (TI) Total Zinc (Zn) Priority Pollutant Metals

BDL BDL BDL BDL BDL 0.005 BDL BDL BDL BDL BDL BDL 0.04 0.005 mg/L 0.005 mg/L 0.001 mg/L 0.0007 mg/L 0.005 mg/L 0.005 mg/L 0.001 mg/L 0.0005 mg/L 0.005 mg/L 0.005 mg/L 0.005 mg/L 0.001 mg/L 0.01 mg/L

BDL • Below Detection Limit Page 1 of 1

# A N A L Y T I C A L S E R V I C E S, I N C
Environmental Monitoring & 

### Laboratory Analysis 110 Technology Parkway Norcross, GA 30092 

# Sl

(770) 734-4200 FAX (770) 734-4201 

### Laboratory Report
Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek Report No. 169451-1 January 30, 2003 Sample Description Macon Water Authority Wastewater, Composite, PPL GA 129, Rocky Creek Effluent, 01/13-01/14/2003, 09:44, received 01/15/2003

Analytical Method Analyte Result Detection Limit Units

EPA 204.2 EPA206.2 EPA 200.7 EPA 213.2 :PA 200.7 EPA 200.7 EPA 239.2 EPA 245.1 EPA 200.7 EPA270.2 EPA 200.7 EPA279.2 EPA 200.7 Metals Total Antimony (Sb) Total Arsenic (As) Total Beryllium (Be) Total Cadmium (Cd) Total Chromium (Cr) Total Copper (Cu) Total Lead (Pb) Total Mercury (Hg) Total Nickel (Ni) Total Selenium (Se) Total Silver (Ag) Total Thallium (TI) Total Zinc (Zn) Priority Pollutant Metals

BDL BDL BDL BDL BDL 0.009 BDL BDL BDL BOL BDL BDL 0.05 0.005 mg/L 0.005 mg/L 0.001 mg/L 0.0007 mg/L 0.005 mg/L 0.005 mg/L 0.001 mg/L 0.0005 mg/L 0.005 mg/L 0.005 mg/L 0.005 mg/L 0.001 mg/L 0.01 mg/L

BDL

- Below Detection Limit Page 1 of 1

# A N A l Y T I C A l S E R V I C E S, I N C 

# Sl Environmental Monitoring & 

## Laboratory Analysis 110 Technology Parkway Norcross, GA 30092 (770) 734-4200 FAX (770) 734-4201 

## Laboratory Report Macon Water Authority PO Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek Report No. 150600-1 March 12, 2002 Sample Description Macon Water Authority

Wastewater, Composite, Priority Pollutants GA 129, Rocky Creek Eff., 01/22-01/23/2002, 10:49, received 01/24/2002

Analytical Method Ana lyle Result Detection Limit Units

EPA204.2 EPA 206.2 oPA 200.7 EPA 213.2 EPA 200.7 EPA200.7 EPA239.2 EPA 245.1 EPA 200.7 EPA 270.2 EPA 200.7 EPA 279.2 EPA 200.7 Metals Total Antimony (Sb) Total Arsenic (As) Total Beryllium (Be) Total Cadmium (Cd} Total Chromium (Cr) Total Copper (Cu) Total Lead (Pb} Total Mercury (Hg) Total Nickel (Ni) Total Selenium (Se) Total Silver (Ag) Total Thallium (TI} Total Zinc (Zn) Priority Pollutant Metals

BDL BDL BDL BDL BDL 0.013 BDL BDL BDL BDL BDL BDL 0.05 0.005 0.005 0.001 0.0007 0.005 0.005 0.001 0.0005 0.005 0.005 0.005 0.001 0.01 mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L

BDL

- Below Detection Limit Page 1 of 1

# A N A L Y T I C A L S E R V I C E S, I N C 

# 51 Environmental Monitoring & Laboratory Analysis 110 Technology Parkway Norcross, GA 30092 (770) 734-4200 FAX {770) 734-4201 

## Laboratory Report
Macon Water Authority P.O. Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek Report No.131164-1 January 15, 20 Sample Description Macon Water Authority Wastewater, composite, Rocky Creek Effluent, 12/12-13/2000, 12:50pm, received 12/15/2000

Analytical Method

EPA200.7 EPA 200.7 EPA 200.7 EPA 200.7 EPA 200.7 EPA 200.7 EPA 200.7 EPA 245.1 EPA 200.7 EPA 200.7 EPA 200.7 EPA 200.7 EPA 200.7 Ana lyte

Metals
Total Antimony {Sb) Total Arsenic (As) Total Beryllium (Be) Total Cadmium (Cd) Total Chromium (Cr) Total Copper (Cu) Total Lead (Pb) Total Mercury (Hg) Total Nickel (Ni) Total Selenium (Se) Total Silver (Ag) Total Thallium (TI) Total Zinc (Zn) Result

Priority Pollutant Metals

BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.04 Detection Limit

0.05 0.03 0.01 0.01 0.01 0.02 0.025 0.0005

0.02 0.04 0.01 0.05 0.02 Units

mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L

BDL

- Below Detection Limit Page 1 of 1

# A N A L Y T I C A l S E R V I C E S, 

# ! N C 

# Sl Environmental Monitoring & 

### Laboratory Analysis 110 Technology Parkway Norcross, GA 30092 (770) 734-4200 FAX (770) 734-4201 

## Laboratory Report
Macon Water Authority P.O. Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek Report No. 

### 117078-1 February 1, 2000 Sample Description Macon Water Authority Wastewater, composite, EPD 129 PP, RC Effluent, 01/12-13/2000, 13:29-13:36, received 01/14/2000

Analytical Method Analyte Result Detection Limit Units

129 Priority Pollutants- Georgia

General Chemistry SM 3500-Cr D Hexavalent Chromium (Cr ' 6 ) BDL 10 ug/L

Metals
EPA 200.7 Total Antimony (Sb) BDL 50 ug/L EPA200.7 Total Arsenic {As) BDL 30 ug/L EPA 200.7 Total Beryllium (Be) BDL 10 ug/L EPA 200.7 Total Cadmium (Cd) BDL 10 ug/L EPA 200.7 Total Chromium (Cr) BDL 10 ug/L EPA 200.7 Total Copper (Cu) BDL 20 ug/L EPA 200.7 Total Lead {Pb) BDL 25 ug/L EPA 245.1 Total Mercury (Hg) BDL 0.5 ug/L EPA 200.7 Total Nickel (Ni) BDL 20 ug/L EPA 200.7 Total Selenium (Se) BDL 40 ug/L EPA 200.7 Total Silver (Ag) BDL 10 ug/L EPA 200.7 Total Thallium {TI) BDL 50 ug/L EPA 200.7 Total Zinc (Zn) 110 20 ug/L

BDL

- Below Detection Limit Page 1 of 1

# Sl ANALYTICAL SERVICES, INC,

ENVIRONMENTAL MONITORING & LABORATORY ANALYSIS

110 TECHNOLOGY PARKWAY • NORCROSS, GA 30092 (770) 734·4200 • FAX (770) 734-4201



### LABORATORY REPORT

Macon Water Authority March 

### 3, 1999 P. 0. Box 

### 108 Macon, GA 

### 31202

Attention: Mr. Mark Wyzalek Report No. 

### 104553-1


### Sample Description

Water, composite, Rocky Creek, 

### 02/09-10/99, 3:10-3:10, received 

### 02/11/99



### RESULTS

129 Priority Pollutants

- Georgia

Result Detection Limit Metals (ug/1) (ug/1)

Total Antimony (Sb) (EPA 

### 200. 7)

.............. . Total Arsenic (As) (EPA 

### 200.7)

............... . Total Beryllium (Be) (EPA 

### 200. 7)

............. . Total Cadmium (Cd) (EPA 

### 200.7)

............... . Total Chromium (Cr) (EPA 

### 200. 7)

.............. . Total Copper (Cu) (EPA 

### 200. 7)

................ . Total Lead (Pb) (EPA 

### 200. 7)

.................. . Total Mercury (Hg) (EPA 

### 245 .1)

............... . Total Nickel (Ni) (EPA 

### 200. 7)

................ . Total Selenium (Se) (EPA 

### 200. 7)

.............. . Total Silver (Ag) (EPA 

### 200.7)

................ . Total Thallium (Tl) (EPA 

### 200. 7)

.............. . Total Zinc (Zn) (EPA 

### 200.7)

.................. . BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 

### 100 50 30 10 10 10 20 25

0.5 20 40 10 50 20

BDL

- Below Detection Limit



# -

A Unit of American Analytical Services, Inc.

# I ANALYTICAL SERVICES, INC.

ENVIRONMENTAL MONITORING & LABORATORY ANALYSIS

110 TECHNOLOGY PARKWAY • NORCROSS, GA 30092 (770) 734-4200 • FAX (770) 734-4201



### LABORATORY REPORT

Macon Water Authority P.O. Box 108 Macon, GA 31202

Attention: Mr. Mark Wyzalek


### Sample Description

Wastewater, composite, RC 129PP, Final Effluent, received 02/27/98



### RESULTS

Priority Pollutant Metals

Metals

Total Antimony (Sb) (EPA 200.7)

.............. . Total Arsenic (As) (EPA 200. 7)

............... . Total Beryllium (Be) (EPA 200. 7)

............. . Total Cadmium (Cd) (EPA 200. 7)

............... . Total Chromium (Cr) (EPA 200. 7)

.............. . Total Copper (Cu) (EPA 200. 7)

................ . Total Lead (Pb) (EPA 200.7)

.................. . Total Mercury (Hg) (EPA 245.1)

............... . Total Nickel (Ni) (EPA 200. 7)

................ . Total Selenium (Se) (EPA 200. 7)

.............. . Total Silver (Ag) (EPA 200.7)

................ . Total Thallium (Tl) (EPA 200. 7)

.............. . Total Zinc (Zn) (EPA 200.7)

.................. . March 16,

Report No.

02/25-26/98,

Result

(ug/1)



### BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 1998

92392-1

12:50-12:46,

Detection Limit

(ug/1)



### 50 30 10 10 10 20 25

0.5 20 40 10 50 20

BDL

- Below Detection Limit

A Unit of American Analytical Services, Inc.HARBOR BRANCH ENVIRONMENTAL LABORATORY



### Trace Metals Analysis



## - Client: Macon Water Authority Station ID: Rocky Creek Effluent Comp. Project!HPN NO.: Priority Pollutant Scan/62195 HSN ID: 62195003 HRS Certification No.: E96080 and 96230 Work Order No.: 2195

Sampled: [ 0/09/96 Received: I 0/10/96

Data Released By: N. Myron Gunsalus Matrix: Enviromental Water

Metal Method Date Digested Date Analyzed Results (mg/L) Qualil1e1· Detection Limit (mg/L)
Antimony 200.7 I 0/16/96 10/17/96 ND 0.050 

### v
Arsenic 200.7 I 0/16/96 10117/96 ND 0.030 ../
Beryllium 200.7 10/16/96 10/17/96 ND 0.010
_,
Cadmium 200.7 I 0/16/96 10/17/96 ND 0.010 ./

Chromium 200.7 10/16/96 10/17/96 ND 0.010 

# "
Copper 200.7 I 0/16/96 10/17/96 ND 0.020 ./

Lead 200.7 10/16/96 10117/96 ND 0.025 o/

Mercury 245.1 10/14/96 I 0/15/96 ND 0.00050 

### J

Nickel 200.7 10/16/96 10/17/96 ND 0.020 ..J

Selenium 200.7 10/16/96 10/17/96 ND 0.040 ..;

Silver 200.7 10/16/96 10/17/96 ND 0.010 

## v

Thallium 279.2 I 0/16/96 I 0/17/96 ND 0.050 1/

Zinc 200.7 10/16/96 10/17/96 0.074 0.020 ;/

ND

- Not Detectable

# Attachment 2: Macon Water Authority, Rocky Creek Biosolids Mercury Data, Undated00.511.522.533.5400.511.522.533.54Mercury (total) Biosolids RC_BIOSOLIDS Plot 1 of 1MWA's Rocky Creek WRF Biosolids bi-monthlyanalyses; mercury is one of the metals tested.Units are mg/kg dry weight. Mercury is one ofthe metals known to be captured by theextended aeration activated sludge process. Alldata submitted annually to Georgia EPD andUS EPA in annual biosolids report and meetsrequirements of 40 CFR 503.

# Attachment 3: Macon Water Authority, Status of MWA lines to Ocmulgee River from Rocky Creek POTW, January 24, 2003AN AFFIRMATIVE ACTION/EQUAL OPPORTUNITY EMPLOYER 

## Macon Water Authority
790 Second Street

– P.O. Box 108 Macon, GA 31202

- 0108 (478) 464

- 5620

 Members Frank C. Ame rson Jr., Chair Javors J. Lucas, Vice

- Chair Dorothy “Dot” C. Black Joe Allen Barbara Knight Charles W. Bishop Henry C. Ficklin R.A. “Tony” Rojas Executive Director



### January 24, 2003

VIA MAIL & FAX 404 362-2691

Je ff Larson Program Manager Georgia EPD 4220 International Parkway Suite 101 Atlanta GA, 30354

Dear Mr. Larson:
Subject: Status of MWA lines to Ocmulgee River from Rocky Creek POTW
This letter is being submitted as per your request concerning the status of MWA lines to the Ocmulgee River from Rocky Creek POTW.

1. Until 1975 a MWA 30” gravity sewer line discharged to the Ocmulgee River.

a. The MWA 30” line clos ely parallels two lines owned by Riverwood International along the service road from Riverwood International to the Ocmulgee. The MWA 30” line lies south of the two Riverwood lines and terminates in the Ocmulgee River next to Riverwood’s discharge line and it is north of the current Rocky Creek NPDES discharge point by about 100 ft. b. When the Rocky Creek POTW came into service in 1975 the 30” line was abandoned and made inactive. A small MWA lift station was built to service only the sanitary sewer from Macon Kraft (now Riverwood International) and what was the Inland Container company; the lift station discharges into the force main from Riverwood International to Rocky Creek POTW. The 30” sewer line was terminated in the wet well of the lift station and bricked in so that no sewer discharge could flow to the Ocmulgee River. The first manhole just downstream of the lift station was filled with grout to further ensure no sewer discharge could occur through the abandoned line.

c. Inspections of this 30” line confirm that it is abandoned and inactive. A break in the line near a creek crossing has been observed, at times of higher groundwater level due to higher Ocmulgee River level, to discharge groundwater inflow and infiltration. Inspection of the broken line on January 23, when the groundwater and Oc mulgee river level was lower showed no water in the line. Today (January 24), when collection system personnel were going to repair the break for aesthetic

### Page 2 of 2 Ja nuary 24, 2003

reasons, groundwater was found to be discharging due to higher river and ground water levels. Collection system personnel will repair the break using brick and grout on the first day that the pipe is again dry.

2. From 1975 to 1991 Rocky Creek POTW discharged to an area immediately adjacent to the facility.

3. In 1991 a 54” line was put into service that conveys the Rocky Creek facility’s discharge to the Ocmulgee. This 54” line for most of its length parallels the abandoned 30” MWA line and lies south of it. Inspections of this line showed no discharge except for the permitt ed NPDES discharge.
It is my understanding that Riverwood International will be submitting their own information to you concerning the water line and discharge line owned by them.
If any further information is required concerning this matter please do not hesitate to contact me.

Sincerely,

Mark Wyzalek Manager, Laboratory & Industrial Monitoring Services Office 478 464-5678, fax 478 745-9531

cc: Ton y Rojas, Terry Forrest, Frank Sanders, and Winton Evans - MWA Mar ion Bard - Riverwood International, via mail and fax 784-4444