5703_MaconCoMSW_5YrCAPEvaluation_DIN27586_20170217

1

February 17, 2017

Ms. Elizabeth Werner
North Carolina Department of Environmental Quality
217 West Jones Street
Raleigh, North Carolina 27603

RE: Five Year Groundwater Contaminant Trend Evaluation
Macon County MSW Landfill, Permit No. 57-03, Macon County, North Carolina

Ms. Werner;

REI Consultants, Inc., on behalf of Macon County, has performed an evaluation of groundwater
monitoring data collected from wells in the area where corrective action activities were conducted at
Macon County’s MSW Landfill, Permit No. 57-03. The evaluation was conducted in order to
evaluate the effectiveness of the corrective action remedies implemented at the facility. This letter
and attachments present the findings and conclusions of the evaluation.

INTRODUCTION

Detections of several Appendix I volatile organic compounds (VOCs) in monitoring wells MW-1A
and MW-1B northwest of the facility’s Phase 1/Phase 2 cell overlap triggered development of an
assessment monitoring plan in 2007 (Bunnell-Lammons Engineering (BLE), Groundwater
Contamination Assessment Plan, BLE Project Number J07-1101-03, September 13, 2007).
Assessment monitoring included the addition of wells MW-1D, MW-5D, and MW-23 to the
monitoring network. Well MW-1D was installed in the vicinity of wells MW-1A and MW-1B in
order to monitor vertical migration of VOCs. Well MW-23 was placed between wells MW-
1A/MW-1B and the Little Tennessee River to monitor horizontal migration of VOCs toward the
surface water body. Well MW-5D was installed in order to replace well MW-5, which lies to the
south of wells MW-1A/MW-1B and had been dry since 2000. These three wells have been
monitored for Appendix I parameters semiannually since the 2nd semiannual 2007 monitoring event.
Assessment monitoring also included analysis of samples collected from wells MW-1A and MW-1B
for all Appendix II parameters during the 2nd semiannual 2007 monitoring event. No additional
parameters beyond the Appendix I list were detected in either well. A map with well locations is
provided in Attachment A.

Due to continued detections of Appendix I VOCs, some of which exceeded North Carolina
groundwater standards promulgated under 15A NCAC 02L .0202 (NC 2L), Macon County
developed a corrective action plan in 2010 (BLE, Limited Elements of a Corrective Action Plan,
BLE Project Number J10-1101-05, August 23, 2010). Corrective action remedies were implemented
in 2011 and consisted of grading of the Phase I cell surface to reduce impoundment/infiltration of

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storm water and to promote positive runoff from the cell; and installation of a landfill gas cut-off
trench containing passive landfill gas vents along the northwest edge of the Phase I area. A map
prepared by McGill Associates, indicating the grading and trench locations, is included as
Attachment B.

The corrective action plan stipulated that an evaluation of the effectiveness of the remedies be
conducted every five years after implementation of the corrective action activities. The first of these
evaluations is this report.

SUMMARY OF MONITORING RESULTS

Detections of Appendix I VOCs have been limited to eight parameters, as discussed individually
below, in wells located west and northwest of the Phase 1/Phase 2 cell overlap area of the landfill.
These wells include MW-1A, MW-1B, MW-1D, MW-5D, and MW-23. VOCs have not been
detected in wells south (MW-3A), southwest (MW-2), or north (MW-22, MW-22A) of the corrective
action area, or in any other monitoring wells or surface water sample locations at the facility. A
summary of VOC results is included as Attachment C. A discussion of the VOC detections, relative
to current Solid Waste Section Limits (SWSLs) and current NC 2L groundwater standards, is as
follows:

Benzene (SWSL = 1 microgram per liter (µg/L), NC 2L = 1 µg/L)

Benzene was detected above the SWSL and groundwater standard in wells MW-1A and MW-1B
from 2001-2002 through 2009, but hasn’t been detected above the SWSL in either well since 2010.
Benzene was detected above the SWSL and groundwater standard in well MW-1D from 2008 to
2010 and in 2012-2013, but hasn’t been detected above the SWSL since the 1st semiannual 2013
monitoring event. Benzene has not been detected above the SWSL in wells MW-5D or MW-23.

Chlorobenzene (SWSL = 3 µg/L, NC 2L = 50 µg/L)

Chlorobenzene was intermittently detected above the SWSL in wells MW-1A and MW-1B from
2003 to 2013, and in well MW-1D intermittently from 2009 to 2013. Chlorobenzene was never
detected above the groundwater standard, and has not been detected above the SWSL in any well
since 2013.

1,4-Dichlorobenzene (SWSL = 1 µg/L, NC 2L = 6 µg/L)

This parameter was first detected above the SWSL in wells MW-1A and MW-1B in 2002, and has
continued to be detected since that time in these wells and in well MW-1D, where it has been
detected since its installation in 2007. In addition, 1,4-dichlorobenzene was detected above the
SWSL in well MW-23 from 2008 to 2010. However, the parameter was detected at concentrations
above the current groundwater standard only intermittently in wells MW-1A and MW-1B from 2003

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to 2008, and has not been detected above the groundwater standard in wells MW-1D or MW-23.
The parameter has not been detected above the SWSL in well MW-5D.

1,1-Dichloroethane (SWSL = 5 µg/L, NC 2L = 6 µg/L)

This parameter was detected above the SWSL in wells MW-1A and MW-1B consistently from 2003
through 2006, and in well MW-1D in 2008 and 2009. However, 1,1-dichloroethane has not been
detected above the SWSL in wells MW-1A and MW-1B since 2006 or in well MW-1D since 2009.
Several of the detections in wells MW-1A and MW-1B exceeded the groundwater standard. None of
the MW-1D detections exceeded the groundwater standard. The parameter has not been detected
above the SWSL in wells MW-5D or MW-23.

Ethylbenzene (SWSL = 1 µg/L, NC 2L = 600 µg/L)

Ethylbenzene was detected above the SWSL in wells MW-1A and MW-1B in 2001 and 2002 at
concentrations well below the groundwater standard. Ethylbenzene has not been detected above the
SWSL in wells MW-1D, MW-5D, or MW-23.

Methylene Chloride (SWSL = 1 µg/L, NC 2L = 5 µg/L)

Methylene chloride was detected above the SWSL once in well MW-1A and once in well MW-1B in
2003. Both concentrations were above the groundwater protection standard. In addition, the
parameter was detected above the SWSL but below the groundwater standard in well MW-5D from
the time of its installation in 2007 through 2010. Methylene chloride has not been detected above
the SWSL in wells MW-1D or MW-23.

Vinyl Chloride (SWSL = 1 µg/L, NC 2L = 0.03 µg/L)

Vinyl chloride was detected above the SWSL and above the groundwater standard in wells MW-1A
and MW-1B from 2001 to 2010. Vinyl chloride has not been detected above the SWSL in either of
these wells since 2010. Vinyl chloride has not been detected above the SWSL in wells MW-1D,
MW-5D, or MW-23.

Xylenes (SWSL = 5 µg/L, NC 2L = 500 µg/L)

Xylenes were detected above the SWSL in well MW-1A from 2000 to 2002 and in well MW-1B
from 2001 to 2003. These detections were all below the groundwater protection standard. Xylenes
were detected above the SWSL but below the groundwater standard in well MW-5D in 2007 and
2008. Xylenes have not been detected above the SWSL in wells MW-1D or MW-23.

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TREND EVALUATION

As indicated in the discussion above, only 1,4-dichlorobenzene continues to be detected above its
SWSL, in wells MW-1A, MW-1B, and MW-1D. All recent detections have been below the
groundwater standard. However, due to the continuing detections, an analysis was conducted in
order to identify potential trends in concentrations of 1,4-dichlorobenzene in wells MW-1A, MW-
1B, and MW-1D.

An initial trend analysis was conducted qualitatively by plotting 1,4-dichlorobenzene data in each
well, starting from when the parameter began being detected consistently, up to the most recent
monitoring event. The parameter has been detected consistently since the 2nd semiannual 2005 event
in wells MW-1A and MW-1B, and since the 2nd semiannual 2008 event in well MW-1D. The plots
are included in Attachment D. As indicated by the plots, concentrations of 1,4-dichlorobenzene
appear generally to be decreasing in wells MW-1A and MW-1B, and no apparent trend is discernable
in well MW-1D.

A more formal, quantitative trend analysis was then conducted using the same data as above. The
method utilized for trend analysis was the linear regression technique (United States Environmental
Protection Agency Office of Resource Conservation and Recovery, Statistical Analysis of
Groundwater Monitoring Data at RCRA Facilities, Unified Guidance, March 2009). This analysis is
included in Attachment E and indicates evidence of statistically significant decreasing trends in 1,4-
dichlorobenzene concentrations in wells MW-1A and MW-1B, and no evidence of an increasing or
decreasing trend in well MW-1D.

CONCLUSIONS

All VOCs that have been detected above SWSLs historically in the corrective action area of the
Macon County MSW Landfill are presently below NC 2L groundwater standards, and no results
have exceeded groundwater standards since the 1st semiannual 2013 monitoring event. Of the eight
VOCs detected historically, only 1,4-dichlorobenzene continues to be detected above the SWSL, in
wells MW-1A, MW-1B, and MW-1D. However, concentrations of 1,4-dichlorobenzene in wells
MW-1A and MW-1B appear to be decreasing, and no significant trend is apparent in well MW-1D.

The implemented corrective actions have been effective in reducing concentrations of VOCs to
below NC 2L groundwater standards. As such, contingency plan measures as proposed in the
Limited Elements of a Corrective Action Plan are not required to be implemented at this time.

RECOMMENDATIONS

We recommend continued sampling of well MW-1D, since 1,4-dichlorobenzene continues to be
detected above the SWSL in the well.

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We recommend that sampling of well MW-23 be discontinued, since no VOCs have been detected
above SWSLs in the well since the 2nd semiannual 2010 monitoring event. The well should be kept
in place, maintained, and utilized for water level monitoring, such that sampling could be resumed if
future monitoring results in wells MW-1A, MW-1B, and/or MW-1D indicate VOCs greater than
groundwater standards.

Should you have any questions or need additional information, please feel free to contact me at (304)
255-2500 or [e-mail].

Sincerely,

Michael Hofe, PE
REI Consultants, Inc.

cc: Chris Stahl, Macon County
Ervin Lane, North Carolina Department of Environmental Quality
Mark Cathey, McGill Associates
Andrew Alexander, BLE

Attachments (5)

ATTACHMENT A

Map of Well Locations in the Vicinity
of Corrective Action Activities
MW-1A
MW-1D
MW-1B
MW-2
MW-23
MONITORING WELL
TOPOGRAPHIC CONTOURS
SURFACE WATER
PROPERTY LINE
WASTE CELL LIMITS
STRUCTURES
ROADS - PAVED
ROADS - UNPAVED
PHASE I
(CLOSED)
PHASE II
(ACTIVE)
N
PREPARED BY: REI CONSULTANTS, INC.
JANUARY 2017
MW-5
MW-5D
MW-3A
MW-22A
MW-22
MW-21
MW-20
MW-17
MACON COUNTY MSW LANDFILL, PERMIT NO. 57-03
FRANKLIN, NORTH CAROLINA
WELLS IN THE VICINITY OF THE CORRECTIVE
ACTION AREA OF FACILITY
SCALE:
0'100'200'

ATTACHMENT B

McGill Associates Map
of Corrective Action Activities
C1
SHEET

ATTACHMENT C

Summary of VOC Data
Attachment C. Summary of VOC Data
Macon County MSW Landfill, Permit No. 57-03
Parameter
SWSL
NC 2L
Well MW-1AMW-1BMW-1DMW-5DMW-23MW-1AMW-1BMW-1DMW-5DMW-23MW-1AMW-1BMW-1DMW-5DMW-23MW-1AMW-1BMW-1DMW-5DMW-23
Feb-1995 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Mar-1995 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Nov-1995 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Apr-1996 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Oct-1996 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
May-1997 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Oct-1997 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
May-1998 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Oct-1998 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Apr-1999 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Oct-1999 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Apr-2000 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Oct-2000 <1 <1 ---<3 <3 ---<1 <1 ---<5 23 ---
Apr-2001 <1 <1 ---<3 <3 ---<1 <1 ---<5 <5 ---
Oct-2001 1.4 1.0 ---<3 <3 ---<1 <1 ---<5 <5 ---
Apr-2002 1.6 1.3 ---<3 <3 ---1 <1 ---<5 <5 ---
Oct-2002 2.4 1.7 ---<3 <3 ---2.2 1.2 ---<5 <5 ---
Apr-2003 <1 <1 ---<3 <3 ---<1 <1 ---7.6 5.3 ---
Oct-2003 <1 5.2 ---<3 6.3 ---<1 6.4 ---8.8 12 ---
Apr-2004 <1 <1 ---5.2 <3 ---<1 <1 ---6.9 6.5 ---
Dec-2004 4.2 3.1 ---5.3 <3 ---6.0 <1 ---7.6 5.8 ---
Apr-2005 3.5 3.2 ---<3 <3 ---<1 <1 ---6.1 5.8 ---
Oct-2005 3.8 3.6 ---5.6 5.0 ---6.7 5.7 ---7.1 6.7 ---
Apr-2006 2.5 2.8 ---<3 <3 ---5.8 5.3 ---5.6 5.3 ---
Oct-2006 2.1 3.0 ---5.3 5.1 ---6.5 6.0 ---6.4 6.4 ---
Apr-2007 2.3 2.2 ---4.6 4.0 ---5.4 4.9 ---<5 <5 ---
Oct-2007 2.2 2.3 <1 <1 <1 5.1 5.0 <3 <3 <3 5.9 5.7 1.3 <1 <1 <5 <5 <5 <5 <5
Apr-2008 1.8 1.9 2.6 <1 <1 3.5 3.6 <3 <3 <3 4.2 4.4 <1 <1 1.3 <5 <5 5.7 <5 <5
Oct-2008 1.4 1.5 1.5 <1 <1 4.9 3.9 <3 <3 <3 6.3 5.0 2.2 <1 1.1 <5 <5 <5 <5 <5
Apr-2009 1.1 1.2 2.6 <1 <1 <3 <3 3.0 <3 <3 3.2 3.6 2.6 <1 1.2 <5 <5 5.3 <5 <5
Oct-2009 <1 <1 2.7 <1 <1 3.2 <3 3.7 <3 <3 4.6 4.1 4.4 <1 1.3 <5 <5 5.8 <5 <5
Apr-2010 <1 <1 1.4 <1 <1 <3 <3 3.1 <3 <3 3.6 3.0 3.9 <1 1.1 <5 <5 <5 <5 <5
Oct-2010 <1 <1 <1 <1 <1 4.0 3.1 <3 <3 <3 5.2 4.2 3.4 <1 1.0 <5 <5 <5 <5 <5
Apr-2011 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 3.2 2.7 3.4 <1 <1 <5 <5 <5 <5 <5
Oct-2011 <1 <1 <1 <1 <1 3.5 <3 <3 <3 <3 4.3 4.0 3.3 <1 <1 <5 <5 <5 <5 <5
Apr-2012 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 3.0 2.7 3.4 <1 <1 <5 <5 <5 <5 <5
Oct-2012 <1 <1 1.4 <1 <1 4.0 <3 3.3 <3 <3 4.2 2.9 3.5 <1 <1 <5 <5 <5 <5 <5
Apr-2013 <1 <1 1.1 <1 <1 <3 <3 3.4 <3 <3 1.5 1.1 3.1 <1 <1 <5 <5 <5 <5 <5
Oct-2013 <1 <1 <1 <1 <1 3.2 <3 <3 <3 <3 3.7 2.8 3.5 <1 <1 <5 <5 <5 <5 <5
Apr-2014 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 1.9 1.6 3.5 <1 <1 <5 <5 <5 <5 <5
Oct-2014 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 2.0 2.0 3.4 <1 <1 <5 <5 <5 <5 <5
Apr-2015 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 2.6 1.9 3.3 <1 <1 <5 <5 <5 <5 <5
Oct-2015 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 2.6 1.5 2.0 <1 <1 <5 <5 <5 <5 <5
Apr-2016 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 1.8 1.4 3.1 <1 <1 <5 <5 <5 <5 <5
Oct-2016 <1 <1 <1 <1 <1 <3 <3 <3 <3 <3 2.7 1.5 3.7 <1 <1 <5 <5 <5 <5 <5
All data in micrograms per liter
SWSL - North Carolina Solid Waste Section Limit
NC 2L - current 15A NCAC 2L .0202 groundwater standard
Data presented relative to current SWSLs and NC 2L groundwater standards
Detections above SWSLs in BOLD; detections greater than NC 2L in RED
1,4-DichlorobenzeneBenzeneChlorobenzene
5
6
1,1-Dichloroethane
6150
113
REI Consultants, Inc. ** PO Box 286 ** Beaver, WV 25813
Attachment C. Summary of VOC Data
Macon County MSW Landfill, Permit No. 57-03
Parameter
SWSL
NC 2L
Well
Feb-1995
Mar-1995
Nov-1995
Apr-1996
Oct-1996
May-1997
Oct-1997
May-1998
Oct-1998
Apr-1999
Oct-1999
Apr-2000
Oct-2000
Apr-2001
Oct-2001
Apr-2002
Oct-2002
Apr-2003
Oct-2003
Apr-2004
Dec-2004
Apr-2005
Oct-2005
Apr-2006
Oct-2006
Apr-2007
Oct-2007
Apr-2008
Oct-2008
Apr-2009
Oct-2009
Apr-2010
Oct-2010
Apr-2011
Oct-2011
Apr-2012
Oct-2012
Apr-2013
Oct-2013
Apr-2014
Oct-2014
Apr-2015
Oct-2015
Apr-2016
Oct-2016
MW-1AMW-1BMW-1DMW-5DMW-23MW-1AMW-1BMW-1DMW-5DMW-23MW-1AMW-1BMW-1DMW-5DMW-23MW-1AMW-1BMW-1DMW-5DMW-23
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---<1 <1 ---6.3 <5 ---
6.4 <1 ---<1 <1 ---1.1 <1 ---8.2 <5 ---
5.8 3.7 ---<1 <1 ---1.7 1.0 ---13 8.9 ---
<1 <1 ---<1 <1 ---1.8 1.4 ---12 6.2 ---
<1 1.2 ---<1 <1 ---2.9 1.8 ---9.2 5.3 ---
<1 <1 ---5.8 <1 ---<1 <1 ---<5 6 ---
<1 <1 ---<1 6.1 ---<1 5.5 ---<5 8.4 ---
<1 <1 ---<1 <1 ---<1 <1 ---<5 <5 ---
<1 <1 ---<1 <1 ---3.9 2.7 ---<5 <5 ---
<1 <1 ---<1 <1 ---3.0 3.0 ---<5 <5 ---
<1 <1 ---<1 <1 ---4.6 3.9 ---<5 <5 ---
<1 <1 ---<1 <1 ---2.8 2.9 ---<5 <5 ---
<1 <1 ---<1 <1 ---2.7 3.0 ---<5 <5 ---
<1 <1 ---<1 <1 ---2.9 2.7 ---<5 <5 ---
<1 <1 <1 <1 <1 <1 <1 <1 1.2 <1 2.2 2.3 <1 <1 <1 <5 <5 <5 5.8 <5
<1 <1 <1 <1 <1 <1 <1 <1 1.7 <1 1.8 1.8 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 1.7 <1 1.8 1.6 <1 <1 <1 <5 <5 <5 6.1 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 1.3 1.3 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 1.2 <1 1.3 1.3 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 1.3 <1 1.2 1.1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 1.5 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
<1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <5 <5 <5 <5 <5
All data in micrograms per liter
SWSL - North Carolina Solid Waste Section Limit
NC 2L - current 15A NCAC 2L .0202 groundwater standard
Data presented relative to current SWSLs and NC 2L groundwater standards
Detections above SWSLs in BOLD; detections greater than NC 2L in RED
Ethylbenzene
1
Methylene Chloride Vinyl Chloride Xylenes, Total
1 1 5
600 5 0.03 500
REI Consultants, Inc. ** PO Box 286 ** Beaver, WV 25813

ATTACHMENT D

Time Series Plots
Attachment D. Time Series Plots of 1,4-Dichlorobenzene
Macon County MSW Landfill, Permit No. 57-03
0
1
2
3
4
5
6
7
20
05
20
06
20
07
20
08
20
09
20
10
20
11
20
12
20
13
20
14
20
15
20
16
20
17
u g /L
1,4-Dichlorobenzene, Well MW-1B
0
1
2
3
4
5
6
7
20
05
20
06
20
07
20
08
20
09
20
10
20
11
20
12
20
13
20
14
20
15
20
16
20
17
u g /L
1,4-Dichlorobenzene, Well MW-1A
0
1
2
3
4
5
6
7
2 0 05
2 0 06
2 0 07
2 0 08
2 0 09
2 0 10
2 0 11
2 0 12
2 0 13
2 0 14
2 0 15
2 0 16
2 0 17
u g /L
1,4-Dichlorobenzene, Well MW-1D
REI Consultants, Inc. ** PO Box 286 ** Beaver, WV 25813

ATTACHMENT E

Trend Calculations
Attachment E. Trend Calculations
Macon County MSW Landfill, Permit No. 57-03
Well MW-1A
Linear Regression Residuals Normality Test
ti xi bi x͆i ri ri2 (t-t̅)2 xi xn-i+1 xn-i+1-xi an-i+1 bi
Oct-2005 6.7 -0.000400182 6.2 0.5 0.25 4052519 -1.6 1.3 2.921 0.4542 1.3266
Apr-2006 5.8 -0.00031373 6.0 -0.2 0.03 3323646 -1.6 1.0 2.603 0.3126 0.8138
Oct-2006 6.5 -0.000316301 5.8 0.7 0.52 2689885 -1.0 1.0 1.965 0.2563 0.5036
Apr-2007 5.4 -0.000233773 5.6 -0.2 0.03 2128935 -0.9 0.9 1.740 0.2139 0.3722
Oct-2007 5.9 -0.000223734 5.4 0.5 0.27 1633506 -0.8 0.8 1.511 0.1787 0.2701
Apr-2008 4.2 -0.000136464 5.2 -1.0 0.95 1199215 -0.8 0.7 1.470 0.1480 0.2175
Oct-2008 6.3 -0.000170676 5.0 1.3 1.77 833728 -0.5 0.6 1.088 0.1201 0.1306
Apr-2009 3.2 -6.87481E-05 4.8 -1.6 2.43 524302 -0.5 0.5 1.053 0.0941 0.0991
Oct-2009 4.6 -7.49409E-05 4.6 0.0 0.00 301496 -0.2 0.5 0.688 0.0696 0.0479
Apr-2010 3.6 -3.92095E-05 4.4 -0.8 0.58 134753 -0.2 0.5 0.664 0.0459 0.0305
Oct-2010 5.2 -2.84018E-05 4.2 1.0 1.09 33888 -0.1 0.2 0.361 0.0228 0.0082
Apr-2011 3.2 -1.98145E-07 4.0 -0.8 0.56 4 0.0 0.0 0.000 0.0000 0.0000
Oct-2011 4.3 2.2826E-05 3.7 0.6 0.30 32010 0.2 -0.1 -0.361
Apr-2012 3.0 3.28371E-05 3.5 -0.5 0.29 136097 0.5 -0.2 -0.664 b=3.8201
Oct-2012 4.2 6.85273E-05 3.3 0.9 0.75 302404 0.5 -0.2 -0.688
Apr-2013 1.5 3.34883E-05 3.1 -1.6 2.53 537162 0.5 -0.5 -1.053
Oct-2013 3.7 9.97867E-05 2.9 0.8 0.57 835237 0.6 -0.5 -1.088
Apr-2014 1.9 6.01545E-05 2.7 -0.9 0.76 1201025 0.7 -0.8 -1.470
Oct-2014 2.0 7.55117E-05 2.5 -0.5 0.28 1635619 0.8 -0.8 -1.511
Apr-2015 2.6 0.000111169 2.3 0.2 0.06 2125510 0.9 -0.9 -1.740
Oct-2015 2.6 0.000126584 2.1 0.5 0.23 2692596 1.0 -1.0 -1.965
Apr-2016 1.8 9.74085E-05 1.9 -0.1 0.01 3326659 1.0 -1.6 -2.603
Oct-2016 2.7 0.000160693 1.7 1.0 0.98 4023687 1.3 -1.6 -2.921
b͆ =-0.001117372 sum ri2 sum (t-t̅)2 sx =0.83
15.26 33703884 W =0.956 greater than 0.881
t̅ =40649 normal assumption not rejected
s2t =1531994.719
x̅ =3.9
s2e =0.726760765
se(b͆) =0.000146844
tb =-7.609255425
tcp =2.518
tb < -tcp ==> assume a significant decreasing trend
Reference: USEPA Unified Guidance, 17.3.1
REI Consultants, Inc. ** PO Box 285 ** Beaver, WV 25813
Attachment E. Trend Calculations
Macon County MSW Landfill, Permit No. 57-03
Well MW-1B
Linear Regression Residuals Normality Test
ti xi bi x͆i ri ri2 (t-t̅)2 xi xn-i+1 xn-i+1-xi an-i+1 bi
Oct-2005 5.7 -0.000340453 5.8 -0.1 0.00 4052519 -1.4 0.8 2.217 0.4542 1.0069
Apr-2006 5.3 -0.000286684 5.5 -0.2 0.06 3323646 -0.8 0.8 1.626 0.3126 0.5083
Oct-2006 6.0 -0.00029197 5.3 0.7 0.46 2689885 -0.7 0.7 1.369 0.2563 0.3508
Apr-2007 4.9 -0.000212128 5.1 -0.2 0.04 2128935 -0.6 0.6 1.237 0.2139 0.2645
Oct-2007 5.7 -0.00021615 4.9 0.8 0.64 1633506 -0.5 0.5 1.021 0.1787 0.1825
Apr-2008 4.4 -0.000142962 4.7 -0.3 0.08 1199215 -0.3 0.5 0.756 0.1480 0.1119
Oct-2008 5.0 -0.000135457 4.5 0.5 0.28 833728 -0.3 0.5 0.713 0.1201 0.0856
Apr-2009 3.6 -7.73416E-05 4.2 -0.6 0.42 524302 -0.2 0.2 0.478 0.0941 0.0450
Oct-2009 4.1 -6.67952E-05 4.0 0.1 0.00 301496 -0.2 0.2 0.371 0.0696 0.0258
Apr-2010 3.0 -3.26746E-05 3.8 -0.8 0.68 134753 -0.1 0.2 0.222 0.0459 0.0102
Oct-2010 4.2 -2.29399E-05 3.6 0.6 0.35 33888 0.1 0.1 0.022 0.0228 0.0005
Apr-2011 2.7 -1.67185E-07 3.4 -0.7 0.48 4 0.1 0.1 0.000 0.0000 0.0000
Oct-2011 4.0 2.12335E-05 3.2 0.8 0.67 32010 0.1 0.1 -0.022
Apr-2012 2.7 2.95534E-05 3.0 -0.3 0.07 136097 0.2 -0.1 -0.222 b=2.5920
Oct-2012 2.9 4.73164E-05 2.7 0.2 0.02 302404 0.2 -0.2 -0.371
Apr-2013 1.1 2.45726E-05 2.5 -1.4 1.95 537162 0.2 -0.2 -0.478
Oct-2013 2.8 7.51112E-05 2.3 0.5 0.21 835237 0.5 -0.3 -0.713
Apr-2014 1.6 5.23506E-05 2.1 -0.5 0.24 1201025 0.5 -0.3 -0.756
Oct-2014 2.0 7.39939E-05 1.9 0.1 0.00 1635619 0.5 -0.5 -1.021
Apr-2015 1.9 8.262E-05 1.7 0.2 0.06 2125510 0.6 -0.6 -1.237
Oct-2015 1.5 7.49767E-05 1.5 0.1 0.01 2692596 0.7 -0.7 -1.369
Apr-2016 1.4 7.57621E-05 1.2 0.2 0.03 3326659 0.8 -0.8 -1.626
Oct-2016 1.5 8.92737E-05 1.0 0.5 0.22 4023687 0.8 -1.4 -2.217
b͆ =-0.001178959 sum ri2 sum (t-t̅)2 sx =0.56
6.98 33703884 W =0.963 greater than 0.881
t̅ =40649 normal assumption not rejected
s2t =1531994.719
x̅ =3.4
s2e =0.332287653
se(b͆) =9.92927E-05
tb =-11.87357295
tcp =2.518
tb < -tcp ==> assume a significant decreasing trend
Reference: USEPA Unified Guidance, 17.3.1
REI Consultants, Inc. ** PO Box 285 ** Beaver, WV 25813
Attachment E. Trend Calculations
Macon County MSW Landfill, Permit No. 57-03
Well MW-1D
Linear Regression Residuals Normality Test
ti xi bi x͆i ri ri2 (t-t̅)2 xi xn-i+1 xn-i+1-xi an-i+1 bi
Oct-2008 2.2 -0.000236643 3.3 -1.1 1.22 2133490 -1.2 1.1 2.327 0.4968 1.1562
Apr-2009 2.6 -0.000243481 3.3 -0.7 0.49 1617086 -1.1 0.6 1.711 0.3273 0.5599
Oct-2009 4.4 -0.000355341 3.3 1.1 1.21 1202635 -0.7 0.5 1.153 0.2540 0.2930
Apr-2010 3.9 -0.00026269 3.3 0.6 0.37 836579 -0.2 0.2 0.396 0.1988 0.0787
Oct-2010 3.4 -0.000183192 3.3 0.1 0.01 535307 -0.1 0.2 0.356 0.1524 0.0543
Apr-2011 3.4 -0.000137622 3.3 0.1 0.01 302112 0.0 0.2 0.174 0.1109 0.0193
Oct-2011 3.3 -8.95881E-05 3.3 0.0 0.00 135901 0.1 0.1 0.059 0.0725 0.0043
Apr-2012 3.4 -4.47302E-05 3.3 0.1 0.01 31915 0.1 0.1 0.025 0.0359 0.0009
Oct-2012 3.5 6.06464E-07 3.3 0.2 0.05 6 0.1 0.1 0.000
Apr-2013 3.1 4.28603E-05 3.3 -0.1 0.02 34356 0.1 0.1 -0.025 b=2.1665
Oct-2013 3.5 9.33473E-05 3.3 0.2 0.04 134214 0.1 0.1 -0.059
Apr-2014 3.5 0.00014174 3.3 0.2 0.06 300691 0.2 0.0 -0.174
Oct-2014 3.4 0.000180425 3.3 0.1 0.01 534877 0.2 -0.1 -0.356
Apr-2015 3.3 0.000222574 3.3 0.1 0.00 828742 0.2 -0.2 -0.396
Oct-2015 2.0 0.000163449 3.3 -1.2 1.50 1195421 0.5 -0.7 -1.153
Apr-2016 3.1 0.000291379 3.3 -0.2 0.02 1629077 0.6 -1.1 -1.711
Oct-2016 3.7 0.000397365 3.2 0.5 0.20 2126793 1.1 -1.2 -2.327
b͆ =-1.95415E-05 sum ri2 sum (t-t̅)2 sx =0.57
5.24 13579202 W =0.896 greater than 0.851
t̅ =41197 normal assumption not rejected
s2t =848700.1176
x̅ =3.3
s2e =0.349131164
se(b͆) =0.000160346
tb =-0.121870944
tcp =2.602
tcp > tb > -tcp ==> insufficient evidence of trend
Reference: USEPA Unified Guidance, 17.3.1
REI Consultants, Inc. ** PO Box 286 ** Beaver, WV 25813