~NATURAL

".RESOURCE

~TECHNOLOGY

Mr.

John Pozza

Ameren Services

One Ameren Plaza

190

I

Chouteau Avenue

St. Louis,

MO 63103

RE:

Groundwater Monitoring Program - Hutsonville Ash Impoundment Pond D

Dear John:

May 5, 2008

(1375-6.2)

This letter outlines a program to monitor groundwater at the above-mentioned facility. included

are

background materials, completion details for the monitoring wells, and a description of a conceptual plan

for monitoring groundwater at this facility that includes proposed adjusted standards.

Upon closure of Pond

D, a formal monitoring plan will be prepared

in accordance with conditions stipulated by the !PCB in

response to the requested variance. The anticipated plan would likely include: listing procedures

for

groundwater sampling, sample preservation and shipment, analytical methods, quality assurance and quality

control, recordkeeping and reporting

of results.

BACKGROUND

Ameren Energy Generating Company (ABG) operates an impoundment system with five ponds at the

Hutsonville generating station (Figure I-Site Plan). Ponds A and B are lined impoundments that currently

receive coal combustion by-product (CCB), Pond C

is a lined impoundment that receives stormwater runoff

and other flows from the plant, and Pond D is an unlined impoundment that formerly received CCB and is

now removed from service.

The fifth pond receives bottom ash. Ponds A, B, C, and the bottom ash pond

are permitted under the IEPA Bureau

of Water's Water Pollution Control program. Pond D, which was

formerly permitted under the Water Pollution Control program, will

be closed under the Bureau ofLand's

Solid Waste program.

Site Hydrogeology

The impoundments are underlain by two water-bearing units separated by materials that have low hydraulic

conductivity (shale bedrock

or silts and clays). The upland portion of the power plant property (the site),

and the western portion

of Pond D, are underlain by a thin (less than 20 feet thick) layer of sand-rich soil,

which is underlain

by Pennsylvanian-age sandstone and then shale (Figure 2, Cross-Section A-A'). The

lowland portion of the site and eastern portion of Pond D are underlain by 90 feet of alluvium in the

Wabash River bedrock valley. The upper 20 feet of alluvium is fine-grained, primarily composed of silt and

clay with thin sand lenses, while the lower

70 feet is coarse-grained, consisting of sand and gravel. Every

boring drilled over the alluvium encountered the fine-grained deposits, and on-site borings that extended to

the underlying sand and gravel (SBlOI, SBI02, MW7D, MW14, MW115, and MW12l) encountered 19 to

25 feet

of these deposits (Figure 2, Cross-Section B-B'). Pennsylvanian-age shale underlies the alluvium.

The shallow upland sand and sandstone, and sand lenses in the fine-grained alluvium are referred to at the

upper migration zone, and constitute the uppermost aquifer at this site. The coarse-grained

alluvium is

referred to as the deep alluvial aquifer. The shale underlying the upland sandstone and the silts

and clays of

the fine grained alluvium separate the upper migration zone from the deep alluvial aquifer.

23713 W, Paul Rd., Ste, 0 • Pewaukee, WI 53072 • Phone, 262.523.9000 . Fa'" 262.523.9001 • www.naturalrt.com

---

Mr.

John Pozzo

May 5, 2008

Page 2

Groundwater flow was mapped for four consecutive quarters during the period used to calculate

background statistics, described later

in this document, and for which complete sample sets were available.

Unfortunately, depth to water readings for all

ofthe upper migration zone and one ofthe deep alluvial

aquifer maps were not collected on the same day. While this discrepancy did not appear to change

map

depictions of the overall direction of groundwater flow, it affected relative readings between wells.

Therefore, a second set

of drawings was produced using data collected after the plant initiated same-date

measurements beginning

in 2006. All maps show that groundwater flow in the upper migration zone and

the deep alluvial aquifer is eastward toward the Wabash River (Figures 3 and 4).

Groundwater Quality

AEG has performed groundwater monitoring at this facility and found elevated concentrations of horon and

sulfate in Pond D monitoring wells screened

in the upper migration zone (Figure Sa and 5b).

In

addition,

there are slightly elevated (higher than background, lower than Class I standards) concentrations

of boron

and sulfate in one monitoring well

in the deep alluvial aquifer (Figure 6a and 6b). Sulfate and boron are

mobile indicator parameters for coal ash leachate.

Impacted Pond D monitoring wells in

the upper migration zone are MW-6, MW-7, MW-8, and MW-IIR.

Concentrations of boron and sulfate have recently' been as high as 16 mgIL and 960

mglL,

respectively

(Figures Sa and 5b). The impacted well within the deep alluvial aquifer is MW-14, where boron and sulfate

concentrations were as high as 1.5 mgIL and 230

mglL,

respectively (Figures 6a and 6b). The fme-grained

alluvial deposits overlying the deep alluvial aquifer occur over an elevation range that overlaps

the upland

shale (Figure 2, Cross-Section

A-A'),combining to form a confining layer that restricts vertical migration of

groundwater. The efficacy of the confining layer is supported by the concentration data, because the only

ash leachate impacts observed in the deep alluvial aquifer are highly localized, and

at concentrations lower

than Class 1 standards and much lower than in

the upper migration zone, despite the fact that Pond D was

first placed in service 40 years ago.

AEG currently has a groundwater monitoring program for Pond A. The Pond A monitoring program is

designed for detection

of a release from that lined pond.

It

consists of five monitoring wells completed in

the upper migration zone', and five parameters with listed limitations, on a monthly basis (Table I).

The

Pond A monitoring program is in compliance with monitoring regulations under 35111. Adm. Code 620, as

evidenced by a permit to operate this facility issued on June 14,2005 (Permit No. 2005-EO-3689).

POND D MONITORING PROGRAM

This monitoring plan was prepared in anticipation of Pond D closure and groundwater monitoring under

35 TIl. Adm. Code 811.318 and 319. Some of the regulatory requirements for that program are designed for

detection monitoring at new sites, where groundwater quality has not been affected

by prior releases. The

situation at Pond D differs because it was constructed prior to modem regulatory requirements, and a

release has already occurred.

Relief from certain monitoring requirements will be sought in a petition to the

I

Based on data collected between September 2002 and March 2005, the period when consecutive quarterly samples were

collected. Boron concentrations as high as 50 mgIL were observed

in

the mid-to-early 1980s.

, Tbe deep alluvial aquifer does not extend beneath

the zone of attenuation at Pond A.

•

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Mr.

John Pozzo

May 5, 2008

Page 3

Pollution Control Board. The following monitoring program (Table 2)

is proposed assuming a positive

decision

on the petition.

Objective

of Pond D Monitoring Program

The objectives of the monitoring program for Pond Dare:

•

To verilY that concentrations in the upper migration zone near this closed facility decrease or

are maintained at levels below adjusted standards. Groundwater flow and transport

modeling suggests that concentrations south

of Pond D (wells MW-6 and MW-llR) will

decrease over time. However, significant concentration decreases are not expected to the

east (MW-7 and MW-8), because these monitoring wells are downgradient

of saturated ash

areas within Pond D, and leachate will continue to be generated by groundwater flowing

through tbis ash, even after the impoundment is capped.

•

To verilY that concentrations

in the deep alluvial aquifer do not increase to levels higher

than background or adjusted grouudwater quality standards as appropriate.

Monitoring Wells

Tables 3 and 4 list monitoring well completion details; boring and well completion logs are provided

in

Attachment E. The existing wells are compliant with 35 TIl. Adm. Code 811.318 with the exception that

well nest MW-7/MW-7D is not within the I

OO-foot zone of attenuation. However these wells are as close

as possible witbout interfering with facility operations, and are capable

of detecting a release from Pond D

as demonstrated by observed concentrations

of coal ash indicator parameters (boron and sulfate) in MW-7.

Furthermore, Ameren is seeking

an adjusted standard to extend the zone of attenuation eastward to the

property boundary, which will cause MW-7 to be within the zone

of attenuation.

Monitoring wells

MW-l and MW-IO provide background data for the upper migration zone. There are no

suitable locations for deep alluvial aquifer background monitoring points, because the Wabash River

overlays the western edge

of the deep alluvial aquifer north of Pond D. Therefore, historic data from MW-

7D and MW-J21 (formerly MW-TW) were used to calculate background for this aquifer. Comparison of

analytical results from tbe proposed deep alluvial aquifer background wells (MW-7D and MW-121) to the

upper migration zone background wells (MW-I and MW-10) shows similar ranges

of groundwater quality

for all parameters except manganese (Figures 7a through 7g). Manganese is released to groundwater from

manganese oxides under reducing conditions, and the concentrations observed at MW-7D and TW-121

(which are higher than those observed

in MW-14) suggest greater manganese dissolution in the confined,

deep alluvial aquifer than

in the unconfmed, upper migration zone background wells. Concentrations for

the ash indicator constituents (boron and sulfate) will be inspected at MW-7D and

MW-12l annually, and if

concentrations increase for two consecutive years, an investigation will be performed to determine whether

these wells are still representative

of background conditions or if they should be reclassified as AGQS

wells, as defined below. All wells used for calculating background will be monitored on the same schedule

as the downgradient wells as provided

in Table 2.

Wells MW-6, MW-7, MW-8, and MW-IIR will be used to monitor downgradient groundwater quality in

the upper migration zone. Wells MW-14, MW-115S, and MW-115D will be used to monitor downgradient

rfII

•

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Mr.

John Pozzo

May 5, 2008

Page 4

groundwater quality

in the deep alluvial aquifer. All of these monitoring wells will serve as AGQS wells as

required by 35 Ill. Adm. Code 81 1.3 I 8(b)(5)3

Analytical

Parnmeter.;

Boron and sulfate are the primary indicators of coal ash leachate. These parameters are persistent, mobile,

and always present

in elevated concentrations in coal ash leachate' Additional monitoring of pH,

temperature, specific conductance, groundwater elevation, and monitoring well depth are required under 35

Ill. Adm. Code 8 I 1.318(e). Biannual monitoring of organic compounds is required under 35 Ill. Adm.

Code 811.319(a)(3); however, there

is no expectation that organics will leach in detectable concentrations

from a CCB management facility because the fly ash and boltom ash have passed through a

power plant

boiler at temperatures

of nearly 3,000"F, which is holter than high-temperature thermal desorption units

(I

,OOO°F) used to volatilize organic compounds from contaminated soils, and equivalent to the holtest-

burning incinerators that degrade organic compounds into hase elements.

As a result, organic compounds

are not expected to be present in fly and boltom ash produced during the combustion process.

In

addition to the field parameters and ash indicator parameters, total dissolved solids

(IDS) and manganese

will be monitored. Each

ofthese parameters had concentrations higher than Class I groundwater quality

standards in some upper migration zone monitoring wells.

IDS concentrations reflect major ion chemistry

(e.g., sulfate)

in the groundwater. Manganese concentrations may, in some cases, be naturally occurring, as

evidenced by concentrations in exceedance of the Class I standard in upper migration zone background

wells

MW-1 and MW-I OD. The monitoring parameters proposed for Pond D are the same as those with

listed limitations in the State operating permit issued for Pond A.

Schedule

Groundwater samples will be obtained upon approval of this petition and for a period of

at least

five years

after

closure' Monitoring will be on a quarterly basis for the first five years after closure. After this five-

year period, Ameren

may request a reduction to semi-annual sample frequency when conditions meet the

criteria

of Title 35, Part 811.319(a)(I )(A), specifically when monitoring effectiveness will not be

compromised, when sufficient quarterly data have been collected to characterize groundwater, and when

concentrations

of monitored constituents at the AGQS wells are below the appropriate AGQS.

6

Beginning 15 years after closure, or five years after concentrations of monitored constituents at AGQS wells

are below the appropriate AGQS, Ameren may request a reduction to annual sampling

if the conditions of

Title 35, Part 811.319(a)(1)(B) are met; specifically when all constituents monitored at the AGQS wells are

3 As noted in the paragraph above, MW-7D and/or MW-121 may in the future be converted to AGQS wells if it becomes

apparent that concentrations are increasing due

to leachate migration from Pond D.

4 Reference:

Chemical Characterization ofFossil Fuel Combustion Wastes.

EPRI Final Report EA-5321, August 1987.

l

The five-year period is appropriate according to Title35, Part 81 I(a)(I)(C) because this is an on-site facility that is not a

municipal solid waste landfill, and has only accepted wastes generated

at the site.

6 Specifically, when concentrations are below the AGQS as defined under Title 35, Part 811.320 or the adjusted standard

as set forth later in this monitoring plan and approved by the Illinois Pollution Control Board if such an adjusted standard

exists for the particular well-constituent combination.

•

NATURAL

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_TECHNOLOGY

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Mr.

John Pozzo

May 5, 2008

Page 5

less than or equal to their appropriate AGQS for eight consecutive quarters and there are no statistically

significant increasing trends

in the monitoring data.

Monitoring will be discontinued when no statistically significant increase

is detected in the concentration of

any constituent above that measured and recorded during the immediately preceding scheduled sampling for

three consecutive years after changing to

an annual monitoring frequency.

Calculation of Bac!q:round

Background concentrations were determined based on analytical data compiled for monitoring wells MW-I

and MWlO

in the upper migration zone, and MW-7D and MW-12l in the deep alluvial aquifer (Appendix D).

As previously noted, comparison

of analytical results from MW-7D and MW-121 to the upper migration zone

background wells (MW-I and MW-l 0) shows similar ranges

of groundwater quality for all parameters except

manganese (Figures 7a through 7g). Furthermore, there are

no trends or seasonality in the concentrations of

the mobile ash indicator constituents, boron and sulfate (Figure 8a and 8b).

The background period consists

of consecutive quarterly sample events from September 2002 through March

2005. Consecutive quarterly data

do not exist prior to or after this period. MW-I has been sampled monthly as

part

of the Pond A monitoring program, while MW-10 was sampled quarterly over the background sample

period. In order to avoid biasing the background data with the large number

of samples from MW-I, only the

samples collected from MW-I during tbe same month

as the MW-10 samples were used in the background

calculation. A Wilcoxon Rank-Sum statistical comparison

of the monthly MW-I data record during the

background data period to the subset

ofMW-l quarterly samples collected during this period demonstrated that

the quarterly and monthly data are statistically similar (Attachment A).

Background concentrations were calculated for the quarterly data according to the following procedure:

I)

Data were reviewed for outliers using Dixon'sOutlier test. One potential outlier was

identified, but was not excluded from the dataset because there was no additional evidence to

suggest that it was

in error (Attachment BI).

2)

Background data were pooled.

3)

Detection frequency was determined (Attachments B2 and B3).

4)

Data normality was determined using the Shapiro-Wi!k W test for normality (Attachments B2

and B3).

5)

Tolerance Intervals were calculated based on the following criteria (Attachments B2 and B3):

•

99 percent confidence level, 95 percent coverage.

•

Data were log-transformed

if necessary to meet the parametric distribution requirement of

the test.

•

Non-detects were replaced with

Y,

the PQL if the percentage of non-detects was less than or

equal to 15%, and Cohen'sadjustment was used for datasets where the detection frequency

was between

15 and 50%. (There were no no-detects in the background data set)

•

A parametric tolerance interval was calculated for parametric or log-parametric datasets.

•

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Mr.

John Pozzo

May 5, 2008

Page 6

•

A non-parametric tolerance interval was determined for non-parametric datasets.

6)

The background concentrations presented

in Table 5 are:

•

The upper tolerance interval for all constituents except for pH.

•

The range between the upper and lower tolerance intervals for pH.

Adjusted

Standards

Adjusted stalldards were determined individually for boron, sulfate, manganese, TDS, and pH at selected

AGQS monitoring well (Table 6) using tolerance intervals.' The tolerance intervals were calculated using

data from consecutive quarterly sample events from September 2002 through March 2005. Consecutive

quarterly data do not exist prior to or after this period. Time series plots were prepared for tbese data

(Figures 9 and 10). The only constituent with

an apparent trend was boron at MW14, and that trend leveled

off over the last five quarters of sampling (Figure lOa). Otherwise, the data showed no appal.ent trends or

seasonality.

The statistical procedure outlined below was followed for each weIVparameter combination to calculate the

tolerance intervals:

1) Data were reviewed for outliers using Dixon'sOutlier test. Two potential outliers were identified,

but not excluded from the dataset because there was no additional evidence to suggest

that tbe

values were

in error (Attachment Cl).

2) Detection frequency was determined (Attachment C2).

3) Data normality was determined using the Shapiro-Wilk W test for normality (Attachment C2).

4) Tolerarlce Intervals were calculated based on the following criteria (Attachment C2):

•

99 percent confidence level,

95 percent coverage.

•

Data were log-transformed

if necessary to meet the parametric distribution requirement of

the test.

•

Non-detects were replaced with

y,

the PQL ifthe percentage of non-detects was less than or

equal to 15%, and Cohen'sadjustroent was used for datasets where the detection frequency

was between

15 and 50%. (There were no no-detects)

•

A parametric tolerance interval was calculated for parametric or log-parametric datasets.

•

A non-parametric tolerance interval was determined for non-parametric datasets.

5) Adjusted standards (Table 6) are proposed for any welVconstituent combination where

the tolerance

interval is outside the lower

of the background data range or Class 1 standard.

7 Adjusted standards were not calculated for MW-115s and MW-115d because concentrations of ash indicator

constituents

were lower than background (in limited sampling).

•

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_TE.CHNOLOGY

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Mr. John Pozzo

May 5, 2008

Page 7

CLOSING

Please do not hesitate to contact me if you have any questions concerning this or other issues associated

with this facility.

Sincerely,

LOGY, INC.

Encs: Figures I through 10

Tables 1 through 6

Attachment

A: Statistical Comparison of Upper Migration Zone and Deep Alluvial Aquifer

Background Well Data

Attachment B: Background Statistical Calculations

Attachment

C: Statistical Calculations for Adjusted Standards

Attachment D: Data used

in Statistical Calculations

Attachment E: Boring Logs and Well Completion Reports

[p:\1300\1375\6_2 Petition Support 2007IMonitoring PlanlExhibit I I Hutsonville Pond D Monitoring Program 200S.doc

CH2\2470697.J

•

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Table 1

Hutsonville Pond

A

Monitoring Program

Wells

Position

Parameters

Frequency

MW-1

Background

!

!

MW-2

Sidegradient

-------

pH, TDS, Boron,

MW-3

Downgradient

Manganese, Sulfate

Monthly

MW-4

Downgradient

MW-5

Downgradient

Notes:

Per Permit No. 2005-EO-3689

2470805JXLS

Resource

Technology

---

Table 2

Hutsonville Pond D Monitoring Program Summary

a. Monitoring Wells

Upper

Mi ration Zone

Purpose/Position

Deep Alluvial A uifer*

Purpose/Position

MW-1

Background/Upgradient

MW-7D

Background /Downgradient

......

_.....~YY.:.~g

_.

__

I?;;ls:~.IlE?!!.~.~!.y.eIlE~.9.i~.~~...

_~YY.:).?~.(!\'I.YY.:I'!YJ._

'?;;ls:~fJE?!!D5!

..

!.'?g'!".~fJ!~9.i.E:.~!.

MW-6

AGQS/Sidegradient

MW-14

AGQS/Downgradient

MW-7

AGQS/Downgradient

MW-115D (TW-115D)

AGQS/Downgradient

MW-8

AGQS/Downgradient

MW-115S (TW-115S)

AGQS/Downgradient

MW-11 R

AGQS/Sidegradient

Note:

* Notations in parentheses are former names of deep alluvial aquifer monitoring points,

# MW-7D and MW-121 may be converted to AGOS wells jffuture monitoring and investigation determines that these

wells are impacted

by

ash leachate impacts from Pond D.

b. Parameters

Parameter

pH

Temperature

Specific Conductance

Groundwater Depth

Well Depth

Boron

Sulfate

Manganese

TDS

c.

Schedule

Period

Schedule

every sample

every sample

every sample

every sample

every sample

every sample

every sample

every sample

every sample

Notes

field parameter

field parameter

field parameter

field parameter

field parameter

CCB indicator parameter

CCB indicator parameter

elevated concentrations near Pond D

eievated concentrations near Pond D

Sample Frequency

o

to 5 years after closure

After 5 years

quarterly

see monitoring plan text

Resource

Technology

---

Table 3

Hutsonville Monitoring Well Elevations, Depth to Bedrock, and Screened Formation

Sunace

TOC'

BOring

Total

Depth to

Bedrock

Bedrock

Hydraulic

Elevation

Elevation

Depth

Depth

Bedrock

Elevation Penetration

Screened

Conductivity

Well

Date Drilled

(ft,

MSL')

(ft,

MSL)

(ft,

BGS')

(ft,

BGS)

(ft,

BGS)

(ft,

MSL)

(ft)

Formation

J

(cm/s)

Pond A

Monitoring Wells

MW-1

2/14/1984

456.4

459.12

9.1

8.9

6.3

450.1

2.7

U - sand,

S5

4.1 E-05

MW-2

2/10/1984

453.4

456.03

21.5

18.1

>21

<431.8

0

U

-s&g

n/a

MW-3

2/9/1984

453.5

455.16

9.4

10.8

10.3

443.2

0.5

U

-s&g

2.7E-02

MW-4

2/13/1984

454.2

457.07

13.4

12.3

10.7

443.5

2.5

U - s&g,

55

n/a

MW-5

2/13/1984

452.2

454.89

19.2

17.9

17.7

434.5

1.4

U - 5&g,

55

8.0E-03

Pond D

Monitoring Wells

MW-1

2/14/1984

456.4

459.12

9.1

8.9

6.3

450.1

2.7

U - sand,

S5

4.1E-05

MW-6

2/9/1984

439.0

443.66

11.4

11.5

8.5

430.5

3.0

U - 5&g,

55

3.2E-02

MW-7

2/8/1984

438.0

442.70

25.0

25.1

>25

<394

0

U - 5i 5&g

2.6E-04

MW-7D

10/5/1998

437.5

438.45

45.0

44.3

>44

<394

0

A-5i5&g

4.8E-02

MW-8

2/7/1984

440.4

444.25

21.5

22.5

>21.5

<419

0

U -

5i 5and

-4-

MW-10

10/7/1998

452.9

454.23

11.0

10.7

7.5

445.4

3.5

U -

5i 5&g, 55

6.2E-04

MW-11R

10/3/2001

440.9

443.55

16.0

15.5

16.0

424.9

0.0

U-5&g

-5-

MW-14

10/3/2001

440.9

443.35

39.0

33.0

>39

<401.9

0.0

A- 5&g

-5-

MW-115D (TW-115D)

5/1/2004

438.4

440.80

105.0

105.0

90.0

348.4

15.0

A- 5&g

1.2E-02

MW-115S (TW-115S)

51112004

438.4

440.89

35.0

35.0

90.0

348.4

0.0

A- 5&g

9.3E-02

MW-121 (MW-TW)

101212001

437.8

440.59

39.5

39.0

>39.5

<398.3

0.0

A-5&g

2.4E-02

Notes:

1. TOe = top of casing

2.

BGS = below ground surface; MSL = mean sea level.

3. U

= upper migration zone, A = deep alluvial aquifer; 5&9 = sand and gravel, si = silty, 55 = sandstone

4. Aquifer test not performed because well

was still recovering from prior sampling.

5. Aquifer test yielded recovery curve that could

not be interpreted.

6. Notations in parentheses are former names

of deep alluvial aquifer monitoring points,

2470805_1XLS

Natural

Resource

Technology

---

Table 4

Monitoring Well Pos itions: Hutsonville Pond D Monitoring Wells

Well

MW-1

MW-6

MW-7

MW-7D

MW-8

MW-10

MW-11R

MW-14

MW-115D (TW-115D)

MW-115S (TW-115S)

MW-121 (MW-TW)

Position Relative

to Pond D

(Background)

Sidegradient

Downgradient

(Background)

Downgradient

(Background)

Sidegradient

Downgradient

Downgradient

Downgradient

(Background)

Distance from

Pond D

>2000

70

140

140

20

>2000

60

80

80

80

30

Within Pond D

Zone

of Attenuation?

no - more than 100

ft

distant

Yes

no - more than 100

ft

distant

no - not uppermost aquifer

Yes

no - more than 100

ft

distant

Yes

no - not uppermost aquifer

no - not uppermost aquifer

no - not uppermost aquifer

no - not uppermost aquifer

Notes:

Distance measurements from base of berm provided

by

Resource

Technology

---

Table Sa

Background Calculation: Hutsonville Pond 0 Monitoring Program

~

Upper Migration Zone

Wells

Parameter

% Non-

Units

Detects

Normal?

log-

normal?

tolerance

Interval

Method

1

Confidence

level

Background

MW1,MW10

MW1, MW1Q

MW1,MW10

MW1,MW10

MW1,MW10

Boron, total

Manganese, total

pH (field)

Sulfate, lotal

Total Filterable Residue (TDS)

mgIL

mgll

,'d

mgll

m,ll

o

o

o

o

o

Ye,

No

Ye'

No

Ye,

Ye,

Ye,

Ye,

Ye,

No

PTI

TTl

PTI

TTl

pn

0.99

0.99

0.99

0.99

0.99

0.22

1,9

6.7 -7.7

'7

566

Table Notes:

1. PTt = parametric tolerance interval, TIl = tolerance interval on log-transformed data, NTI = non-parametric tolerance interval

2. No standards are proposed for field parameters other than pH

Table 5b

Background Calculation: Hutsonville Pond 0 Monitoring Program. Deep Alluvial Aquifer

Wells

Parameter

%Non~

Units

Detects

Normal?

Log-

normal?

TOfefanee

Interval

Method'

Confidence

Level

Background

MW7D,MW121

MW7D,MW121

MW7D,MW121

MW7D,MW121

MW7D,MW121

Boron, lotal

Manganese, total

pH (field)

Sulfate, total

Total Filterable Residue (TDS)

mg/L

mg/L

"d

mgll

mg/L

o

o

o

o

o

No

No

Ye,

Ye,

Ye,

Ye'

Ye,

Y"

Ye,

Ye'

TTl

TTl

PTI

PTI

PTI

0.99

0.99

0.99

0.99

0.99

0.27

2.4

7.0 -7.8

84

500

Table Notes:

1. PTI = parametric tolerance interval, TTl = tolerance interval on log-transformed data, NTI = non-parametric tolerance interval

2. No standards are proposed for field parameters other than pH

2470805_1 XLS

Natural

Resource

Technology

---

Table 6a

Proposed Adjusted Standards: Hutsonville Pond D Monitoring Program - Upper Migration Zone

lolerance

TolerancQ

Log-

% Non-

Interval

Confidence

Interval

Adjusted

Well

Parameter

Units Normal?

normal?

Detects

Method

1

Level

Limit

Background

Class I

Standard

MW-6

Boron, tolal

mg/L

Ye,

Ye,

0.0

PTI

0.99

21.5

0.22

2.0

21.5

MW-6

Manganese, total

mg/L

No

No

0.0

NTI

0.43

3.6

1.9

0.15

3.6

MW-6

pH (field)

std

Ye,

Ye,

0.0

PTI

0.99

6.1-7.9

6.7 - 7.7

6.5 -g.O

6.1 -7.9

MW-6

Sulfate, total

mg/L

Ye,

Ye,

0.0

PTI

0.99

576

97

400

576

MW-6

Total Filterable Residue (TDS)

mg/L

Ye,

Ye,

0.0

PTI

0.99

1128

566

1200

1128

MW-7

Boron,lotal

mg/L

No

No

0.0

NTI

0.43

2.6

0.22

2.0

2.6

MW-7

Manganese, lotal

mglL

No

Ye,

0.0

TTl

0.99

1.8

1.9

0.15

1.9

MW-7

pH (field)

std

Ye,

Ye,

0.0

PTI

0.99

6.4-7.5

6,7 - 7.7

6.5 -g.O

6.4-7.7

MW-7

Sulfate, total

mg/L

Ye,

Ye,

0.0

PTI

0.99

416

97

400

416

MW-7

Tolal Filterable Residue (TDS)

mg/L

Ye,

Ye,

0.0

PTI

0.99

1262

566

1200

1262

MW-8

Boron, total

mglL

Ye,

Ye,

0.0

PTI

0.99

16.2

0.22

2.0

16.2

MW-6

Manganese, total

mg/L

Ye'

Ye'

0.0

PTI

0.99

6.1

1.9

0.15

6.1

MW-8

pH (field)

old

No

No

0.0

NTI

0,43

6.9.7.4

6.7 -7.7

6.S-9.0

none

MW-6

Sulfate. tolal

mg/L

Ye,

Ye,

0.0

PTI

0.99

1241

97

400

1241

MW-8

Tolal Filterable Residue (TDS)

mg/L

No

No

0.0

NTI

0.43

1800

566

1200

1800

MW-11R

Boron, total

mg/L

Ye,

Ye,

0.0

PTI

0.99

11.6

0.22

2.0

11.6

MW-11R

Manganese, total

mg/L

No

Ye,

0.0

TTl

0.99

9.5

1.9

0.15

9.5

MW-11R

pH (field)

,ld

No

No

0.0

NTI

DAD

6.0 -7.2

6,7 - 7.7

6.5- 9.0

6.0-7.7

MW-11R

Sulfate. total

mg/L

No

No

0.0

NTI

0.43

720

97

400

720

MW-11R

Total Filterable Residue (TDS)

mglL

No

No

0.0

NTI

0.43

1300

566

1200

1300

Table Notes:

1. PTI = tolerance interval, TTl = tolerance interval on log-transformed data, NT! = larger of non-parametric tolerance interval or mean+sldev.2

2. No standards are proposed for field parameters other than pH

2470805~

1XLS

Natural

Resource

Technology

---

Table 6b

Proposed Adjusted Standards: Hutsonville Pond 0 Monitoring Program. Deep Alluvial Aquifer

lolerance

Tolerance

Log-

%

Non.

Interval

Confidence

Intarva!

Adjusted

Well

Parameter

Units Normal?

normal?

Detects

Method

1

Level

Limit

Background

Class.

Standard

MW-14

Boron, total

mg/l

Ye,

Ye,

0.0

PTI

0.99

2.3

0.27

2.0

2.3

MW-14

Manganese, total

mg/L

Ye,

Ye,

0.0

PTI

0.99

0.67

2.4

0.15

2.4

MW-14

pH (field)

,td

No

No

0.0

NTI

0.43

6.8-7.3

7.0.7.8

6.5 - 9.0

6.8-7.8

MW-14

Sulfate, lotal

mg/L

Ye,

No

0.0

PTI

0.99

305

84

400

305

MW.14

Total Fillerable Residue (TDS)

mg/l

No

No

0.0

NTI

0.43

830

500

1200

830

Table Notes:

1. PTI "" tolerance interval, TTl == tolerance interval on log-transformed data, NTI

='

larger of non-parametric tolerance interval or mean+stdev"2

2. No standards are proposed for field parameters other than pH

2470805_1.XLS

Natural

Resource

Technology

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

Box Whisker Plot - 1 Parameter, Multi Location

Boron, total mg/L

Locations

0.0

3.2

6.4

9.6

12.8

16.0

MW1

MW10

MW11R

MW6

MW7

MW8

Figure 5a. Box-whisker plot showing boron concentrations from September 2002 through

March 2005. MW1 and MW10 are background wells.

Box Whisker Plot - 1 Parameter, Multi Location

Sulfate, total mg/L

Locations

0

200

400

600

800

1000

MW1

MW10

MW11R

MW6

MW7

MW8

Figure 5b. Box-whisker plot showing sulfate concentrations from September 2002 through

March 2005. MW1 and MW10 are background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Manganese, total mg/L

Locations

0

1

2

3

4

5

MW1

MW10

MW11R

MW6

MW7

MW8

Figure 5e. Box-whisker plot showing manganese concentrations from September 2002

through March 2005. MW1 and MW10 are background wells.

Box Whisker Plot - 1 Parameter, Multi Location

pH (field) std

Locations

5.5

6.0

6.5

7.0

7.5

8.0

MW1

MW10

MW11R

MW6

MW7

MW8

Figure 5f. Box-whisker plot showing pH values from September 2002 through March 2005.

MW1 and MW10 are background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Total Filterable Residue (TDS) mg/L

Locations

0

400

800

1200

1600

2000

MW1

MW10

MW11R

MW6

MW7

MW8

Figure 5g. Box-whisker plot showing TDS concentrations from September 2002 through

March 2005. MW1 and MW10 are background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Boron, total mg/L

Locations

0

4

8

12

16

MW121

MW14

MW7D

Figure 6a. Box-whisker plot showing boron concentrations from September 2002 through

March 2005. MW121 and MW7D are background wells.

Box Whisker Plot - 1 Parameter, Multi Location

Sulfate, total mg/L

Locations

0

200

400

600

800

1000

MW121

MW14

MW7D

Figure 6b. Box-whisker plot showing sulfate concentrations from September 2002 through

March 2005. MW121 and MW7D are background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Manganese, total mg/L

Locations

0

1

2

3

4

5

MW121

MW14

MW7D

Figure 6e. Box-whisker plot showing manganese concentrations from September 2002

through March 2005. MW121 and MW7D are background wells.

Box Whisker Plot - 1 Parameter, Multi Location

pH (field) std

Locations

5.5

6.0

6.5

7.0

7.5

8.0

MW121

MW14

MW7D

Figure 6f. Box-whisker plot showing pH values from September 2002 through March 2005.

MW121 and MW7D are background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Total Filterable Residue (TDS) mg/L

Locations

0

400

800

1200

1600

2000

MW121

MW14

MW7D

Figure 6g. Box-whisker plot showing TDS concentrations from September 2002 through

March 2005. MW121 and MW7D are background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Boron, total mg/L

Locations

0

4

8

12

16

MW1

MW10

MW121

MW7D

Figure 7a. Box-whisker plot showing background boron concentrations from September

2002 through March 2005. MW1 and MW10 are upper migration zone background wells,

and MW121 and MW7D are deep alluvial aquifer background wells.

Box Whisker Plot - 1 Parameter, Multi Location

Sulfate, total mg/L

Locations

0

200

400

600

800

1000

MW1

MW10

MW121

MW7D

Figure 7b. Box-whisker plot showing background sulfate concentrations from September

2002 through March 2005. MW1 and MW10 are upper migration zone background wells,

and MW121 and MW7D are deep alluvial aquifer background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Manganese, total mg/L

Locations

0

1

2

3

4

5

MW1

MW10

MW121

MW7D

Figure 7e. Box-whisker plot showing background manganese concentrations from

September 2002 through March 2005. MW1 and MW10 are upper migration zone

background wells, and MW121 and MW7D are deep alluvial aquifer background wells.

Box Whisker Plot - 1 Parameter, Multi Location

pH (field) std

Locations

5.5

6.0

6.5

7.0

7.5

8.0

MW1

MW10

MW121

MW7D

Figure 7f. Box-whisker plot showing background pH values from September 2002 through

March 2005. MW1 and MW10 are upper migration zone background wells, and MW121 and

MW7D are deep alluvial aquifer background wells.

---

Box Whisker Plot - 1 Parameter, Multi Location

Total Filterable Residue (TDS) mg/L

Locations

0

400

800

1200

1600

2000

MW1

MW10

MW121

MW7D

Figure 7g. Box-whisker plot showing background TDS concentrations from September

2002 through March 2005. MW1 and MW10 are upper migration zone background wells,

and MW121 and MW7D are deep alluvial aquifer background wells.

---

B, tot (mg/L)

MW1

MW10

MW7D

Analysis Result

Sample Date

Class I

0.0

0.4

0.8

1.2

1.6

2.0

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

SO4, tot (mg/L)

MW1

MW10

MW7D

Analysis Result

Sample Date

Class I

0

100

200

300

400

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 8a. Time series plots comparing boron (top) and sulfate (bottom) concentrations in

deep alluvial aquifer background well MW7D to upper migration zone background wells

MW1 and MW10.

---

B, tot (mg/L)

MW1

MW10

MW121

Analysis Result

Sample Date

Class I

0.0

0.4

0.8

1.2

1.6

2.0

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

SO4, tot (mg/L)

MW1

MW10

MW121

Analysis Result

Sample Date

Class I

0

50

100

150

200

250

300

350

400

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 8b. Time series plots comparing boron (top) and sulfate (bottom) concentrations in

deep alluvial aquifer background well MW121 to upper migration zone background wells

MW1 and MW10.

---

B, tot (mg/L)

MW1 MW10 MW11R MW6 MW7 MW8

Analysis Result

Sample Date

Class I

0

5

10

15

20

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 9a. Time series plots showing boron concentrations in upper migration zone

monitoring wells

SO4, tot (mg/L)

MW1 MW10 MW11R MW6 MW7 MW8

Analysis Result

Sample Date

Class I

0

200

400

600

800

1000

1200

1400

1600

1800

2000

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 9b. Time series plots showing sulfate concentrations in upper migration zone

monitoring wells

---

Mn, tot (mg/L)

MW1 MW10 MW11R MW6 MW7 MW8

Analysis Result

Sample Date

Class I

0

1

2

3

4

5

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 9c. Time series plots showing manganese concentrations in upper migration zone

monitoring wells

pH (field) (std)

MW1 MW10 MW11R MW6 MW7 MW8

Analysis Result

Sample Date

5.5

6.0

6.5

7.0

7.5

8.0

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 9d. Time series plots showing pH values in upper migration zone monitoring wells

---

TDS (mg/L)

MW1 MW10 MW11R MW6 MW7 MW8

Analysis Result

Sample Date

Class I

0

500

1000

1500

2000

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 9e. Time series plots showing TDS concentrations in upper migration zone

monitoring wells

---

B, tot (mg/L)

MW121

MW14

MW7D

Analysis Result

Sample Date

Class I

0.0

0.5

1.0

1.5

2.0

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 10a. Time series plots showing boron concentrations in deep alluvial aquifer

monitoring wells (MW115s and MW115d not monitored during this period)

SO4, tot (mg/L)

MW121

MW14

MW7D

Analysis Result

Sample Date

Class I

0

400

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 10b. Time series plots showing sulfate concentrations in deep alluvial aquifer

monitoring wells (MW115s and MW115d not monitored during this period)

---

Mn, tot (mg/L)

MW121

MW14

MW7D

Analysis Result

Sample Date

Class I

0

1

2

3

4

5

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 10c. Time series plots showing manganese concentrations in deep alluvial aquifer

monitoring wells (MW115s and MW115d not monitored during this period)

pH (field) (std)

MW121

MW14

MW7D

Analysis Result

Sample Date

5.5

6.0

6.5

7.0

7.5

8.0

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 10d. Time series plots showing pH values in deep alluvial aquifer monitoring wells

(MW115s and MW115d not monitored during this period)

---

TDS (mg/L)

MW121

MW14

MW7D

Analysis Result

Sample Date

Class I

0

200

400

600

800

1000

1200

1400

1600

1800

2000

1/1/2002

1/1/2003

1/1/2004

1/1/2005

1/1/2006

Figure 10e. Time series plots showing TDS concentrations in deep alluvial aquifer

monitoring wells (MW115s and MW115d not monitored during this period)

---

March 3, 2008

3:51:11 PM

Hutsonville Ash Impoundment

User Supplied Information

Data Deseasonalization:

Option for LT Pts:

x 0.5

Confidence level:

Period Length, mn:

3

Data Averaged?

No

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

09/01/2002 to 03/31/2005

Compliance Locations:

Wilcoxon Rank Sum Test for Two Group Comparison

99.00%

No

Background Locations:

MW1(Monthly)

Parameter:

Code

Name

Units

00400

pH (field)

std

Compliance Location:

Location ID

Location Type

MW1

Upper Zone

Background Location(s):

MW1(Monthly)

Upper Zone

W test (background):

Data is Normal

(At a significance level of 0.010)

W test (Compliance) :

Data is Normal

(At a significance level of 0.010)

Compliance Statistics (One-Sided Test):

Test Statistic

Avg Pts.

Less Than Pts.

Expected Value

Std Dev

Z-Value

Z-Critical

Null Hypothesis, Ho: All locations are from the same population.

Accept the Null Hypothesis, Ho.

11

0

231.000

33.800

0.370

2.326

MANAGES

1

---

March 3, 2008

3:51:11 PM

Hutsonville Ash Impoundment

User Supplied Information

Data Deseasonalization:

Option for LT Pts:

x 0.5

Confidence level:

Period Length, mn:

3

Data Averaged?

No

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

09/01/2002 to 03/31/2005

Compliance Locations:

Wilcoxon Rank Sum Test for Two Group Comparison

99.00%

No

Background Locations:

MW1(Monthly)

Parameter:

Code

Name

Units

00945

Sulfate, total

mg/L

Compliance Location:

Location ID

Location Type

MW1

Upper Zone

Background Location(s):

MW1(Monthly)

Upper Zone

W test (background):

Data is Not Normal

(At a significance level of 0.010)

W test (Compliance) :

Data is Normal

(At a significance level of 0.010)

Compliance Statistics (One-Sided Test):

Test Statistic

Avg Pts.

Less Than Pts.

Expected Value

Std Dev

Z-Value

Z-Critical

Null Hypothesis, Ho: All locations are from the same population.

Accept the Null Hypothesis, Ho.

11

0

231.000

33.941

-0.412

2.326

MANAGES

2

---

March 3, 2008

3:51:11 PM

Hutsonville Ash Impoundment

User Supplied Information

Data Deseasonalization:

Option for LT Pts:

x 0.5

Confidence level:

Period Length, mn:

3

Data Averaged?

No

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

09/01/2002 to 03/31/2005

Compliance Locations:

Wilcoxon Rank Sum Test for Two Group Comparison

99.00%

No

Background Locations:

MW1(Monthly)

Parameter:

Code

Name

Units

01022

Boron, total

mg/L

Compliance Location:

Location ID

Location Type

MW1

Upper Zone

Background Location(s):

MW1(Monthly)

Upper Zone

W test (background):

Data is Not Normal

(At a significance level of 0.010)

W test (Compliance) :

Data is Normal

(At a significance level of 0.010)

Compliance Statistics (One-Sided Test):

Test Statistic

Avg Pts.

Less Than Pts.

Expected Value

Std Dev

Z-Value

Z-Critical

Null Hypothesis, Ho: All locations are from the same population.

Accept the Null Hypothesis, Ho.

11

0

231.000

33.685

-0.045

2.326

MANAGES

3

---

March 3, 2008

3:51:11 PM

Hutsonville Ash Impoundment

User Supplied Information

Data Deseasonalization:

Option for LT Pts:

x 0.5

Confidence level:

Period Length, mn:

3

Data Averaged?

No

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

09/01/2002 to 03/31/2005

Compliance Locations:

Wilcoxon Rank Sum Test for Two Group Comparison

99.00%

No

Background Locations:

MW1(Monthly)

Parameter:

Code

Name

Units

01055

Manganese, total

mg/L

Compliance Location:

Location ID

Location Type

MW1

Upper Zone

Background Location(s):

MW1(Monthly)

Upper Zone

W test (background):

Data is Not Normal

(At a significance level of 0.010)

W test (Compliance) :

Data is Normal

(At a significance level of 0.010)

Compliance Statistics (One-Sided Test):

Test Statistic

Avg Pts.

Less Than Pts.

Expected Value

Std Dev

Z-Value

Z-Critical

Null Hypothesis, Ho: All locations are from the same population.

Accept the Null Hypothesis, Ho.

11

0

231.000

33.963

0.294

2.326

MANAGES

4

---

March 3, 2008

3:51:11 PM

Hutsonville Ash Impoundment

User Supplied Information

Data Deseasonalization:

Option for LT Pts:

x 0.5

Confidence level:

Period Length, mn:

3

Data Averaged?

No

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

09/01/2002 to 03/31/2005

Compliance Locations:

Wilcoxon Rank Sum Test for Two Group Comparison

99.00%

No

Background Locations:

MW1(Monthly)

Parameter:

Code

Name

Units

70300

Total Filterable Residue (TDS)

mg/L

Compliance Location:

Location ID

Location Type

MW1

Upper Zone

Background Location(s):

MW1(Monthly)

Upper Zone

W test (background):

Data is Normal

(At a significance level of 0.010)

W test (Compliance) :

Data is Normal

(At a significance level of 0.010)

Compliance Statistics (One-Sided Test):

Test Statistic

Avg Pts.

Less Than Pts.

Expected Value

Std Dev

Z-Value

Z-Critical

Null Hypothesis, Ho: All locations are from the same population.

Accept the Null Hypothesis, Ho.

11

0

231.000

33.890

0.044

2.326

MANAGES

5

---

03/03/2008

3:55:51PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Background Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW1

pH (field), std

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.182

Test Statistic, low extreme of all data: T1 = 0.268

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW10

pH (field), std

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.048

Test Statistic, low extreme of all data: T1 = 0.300

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW121

pH (field), std

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.387

Test Statistic, low extreme of all data: T1 = 0.000

No Outliers

1

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:55:51PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Background Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7D

pH (field), std

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.425

Test Statistic, low extreme of all data: T1 = 0.566

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW1

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.686

Test Statistic, low extreme of all data: T1 = 0.057

02/05/2003

87.000

False

1

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW10

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.400

Test Statistic, low extreme of all data: T1 = 0.222

No Outliers

2

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:55:51PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Background Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW121

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.310

Test Statistic, low extreme of all data: T1 = 0.116

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7D

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.250

Test Statistic, low extreme of all data: T1 = 0.367

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW1

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.460

Test Statistic, low extreme of all data: T1 = 0.121

No Outliers

3

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:55:51PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Background Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW10

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.403

Test Statistic, low extreme of all data: T1 = 0.156

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW121

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.497

Test Statistic, low extreme of all data: T1 = 0.204

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7D

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.490

Test Statistic, low extreme of all data: T1 = 0.269

No Outliers

4

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:55:51PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Background Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW1

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.100

Test Statistic, low extreme of all data: T1 = 0.371

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW10

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.614

Test Statistic, low extreme of all data: T1 = 0.061

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW121

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.522

Test Statistic, low extreme of all data: T1 = 0.237

No Outliers

5

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:55:51PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Background Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7D

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.269

Test Statistic, low extreme of all data: T1 = 0.594

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW1

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.417

Test Statistic, low extreme of all data: T1 = 0.158

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW10

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.125

Test Statistic, low extreme of all data: T1 = 0.333

No Outliers

6

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:55:51PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Background Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW121

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.569

Test Statistic, low extreme of all data: T1 = 0.549

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7D

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.167

Test Statistic, low extreme of all data: T1 = 0.267

No Outliers

7

MANAGES

Based on Dixons one-sided outlier test

---

March 3, 2008

Appendix B2: Tolerance Interval Calculation Background (Upper)

Compliance Date Range: 01/01/2008 to 01/01/2008

0.01

0

95%

Interwell

Background Locations:

MW1,MW10

Background Date Range: 09/01/2002 to 03/31/2005

4:04:21 PM

Comparison Method if all Background Results are Non-Detect:

STmdl = Last MDL

Statistical Test for Parametric Background Data Distributions:

STpar = Parametric Tolerance Interval on Background

Statistical Test for Cases with High Percentage of Non-Detect Background Data:

Statistical Test for Cases with High Percentage of Non-Detect Background Data:

STnon = Non-Parametric Tolerance Interval on background

STlow1 = Non-Parametric Tolerance Interval on background (ND Frequency > 50%)

Background Comparison:

Number of Verification Samples:

Default Type 1 Individual Comparison Error Level

(False Positive Rate) for tests other than Prediction Interval

Non-Detect Processing (Parametric Tests):

Tolerance Interval Coverage:

Compliance Locations:

Null

Non-Detect Processing (All Other):

<=15% using 1/2 PQL (MDL * 10/3)

>15% using Cohen's Adj.

<=50% using MDL * 1.0

>50% using MDL * 1.0

Statistical Test for Non-Parametric Background Data Distributions:

STlow2 = Non-Parametric Tolerance Interval on background (ND Frequency > 50%)

---

Compliance

Normal /

Percent

of Non

detects

Count

Of Bkg

Results

Confidence

Location

Parameter

Sample Date

Lognormal

Test

Level

Upper Limit

Lower Limit

Analysis Result Exceedance Trend

01/01/2008

Null

Boron, Tot, mg/L

22

0.00

Yes/Yes

STpar

99.00

0.216

0.000

No

01/01/2008

Null

Manganese, Tot,

22

0.00

No/Yes

STpar

0.000

No

mg/L

99.00

1.869

01/01/2008

Null

pH (field), std

22

0.00

Yes/Yes

STpar

99.00

7.685

6.739

0.000

Yes

01/01/2008

Null

Sulfate, Tot, mg/L

22

0.00

No/Yes

STpar

99.00

97.460

0.000

No

01/01/2008

Null

TDS, mg/L

22

0.00

Yes/No

STpar

99.00

566.259

0.000

No

MANAGES

2

---

March 3, 2008

4:04:20

PM

Hutsonville Ash Impoundment

Normal Tolerance Interval on Background

Compliance Analysis

User Supplied Information

Background Date Range:

Compliauce Date Range:

Compliance Locations:

Background Locations:

COMPLIANCE

Location

Null

09/0112002 to 03/3112005

0110112008 to 0110112008

Null

MW1,MWI0

Tolerance Coverage (Gamma): 95%

Parameter Code;

00400

Parameter Name;

pH (field)

.!1.ni.U..;.

std

TL CUllller) value

7.7

Sample

Sample

Greater than

Date

Result

IL (Upper)

1/112008

0.000

N

Parameter Code;

00945

Parameter Name;

Sulfate, Tot

.lin..it1;.

mglL

II, (lJIlller) value

97.5

Sample

Sample

Greater than

Date

Result

IL (Upper)

11112008

0.000

N

Parameter Code;

01022

Parameter Name;

Boron, Tot

.!1.ni.U..;.

mglL

TL (lJllller) value

0.2

Sample

Sample

Greater than

Date

Result

IL (Upperl

1/1/2008

0.000

N

Data Transformation:

Confidence Leyel;

Option for I.T Pts,:

TL (Lower) value

6.7

Lower than

IL (Lower)

y

Data Transformation;

Confidence Level:

Option for I.T Pts.;

Data Transformation:

Confidence Level;

Option for LT Pts.;

None

0,99%

1/2 PQL (MOL

*

10/3)

Natural Log

0.99%

112

PQL (MOL

*

10/3)

None

0.99%

1/2 PQL (MOL

*

10/3)

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than

TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

Lower Limit only listed

for two sided test.

MANAGES

---

March 3, 2008

4:04:20

PM

Hutsonville Ash Impoundment

Normal Tolerance Interval on Background

Compliance Analysis

User Supplied Information

Background Date Range:

Compliance Date Range:

Compliance Locations:

Background Locations:

09/0112002 to 03/3112005

0110112008

to 0110112008

Null

MWI,MWIO

Tolerance Coverage (Gamma):

95%

--~~~--~~~~-

----

-~~~

...

_--

COMPLIANCE

Parameter Code:

01055

Parameter Name:

Manganese, Tot

.I..1ai.ti;.

mglL

TL (Upper) value

1.9

Sample

Sample

Greater than

Date

Result

TL (Upper)

1/1/2008

0.000

N

Parameter Code:

70300

Parameter Name:

TDS

!In.i.ts.;.

mglL

TL (lJpper) value

566.3

Sample

Sample

Greater than

Date

Result

TL (Upper)

111/2008

0.000

N

Data Transformation:

Confidence Leyel:

Option for itT Pts,;

Data Transformation:

Confidence Leyel:

Option for itT Pts.:

Natural Log

0.99%

112 PQL (MOL

*

10/3)

None

0.99%

112 PQL (MOL

*

10/3)

Note: Confidence Level is sometimes referred to as Tolerance Coefficient

When "Greater than TL (Upper)" is Y, this indicates statistical evidence ofexceedance of the upper tolerance limit.

Lower

Limit only listed for two sided test

MANAGES

2

---

March 3, 2008

4:04:20

PM

Hutsonville Ash Impoundment

Normal Tolerance Interval on Background

Background Data Pool

Background Date Range:

Compliance Date Range:

Compliance Locations:

Background Locations:

BACKGROUND

Location

Pooled

09/0112002 to 03/3112005

01101/2008 to 0110112008

Null

MWI,MWIO

~

Upper Zone

Tolerance Coverage (Gamma):

Option for LT Pts:

Total Pts

22

95%

112 PQL (MDL

*

10/3)

% LT Pts

o

Parameter Code:

00400

Parameter Name;

pH (field)

std

Pooled Results:

Data Transformation;

COnfidence Leyel;

None

0.99%

Normal

Yes

Mean

7.212

StdDev

0.154

K

Value

3.078

TL (Lower)

6.739

TU (Upper)

7.685

Parameter Code;

00945

Parameter Name;

Sulfate, Tot

lin..i.t1;,

mg/L

Pooled Results:

Normal

Mean

StdDev

K

Value

Yes

35.091

15.997

2.729

Data Transformation;

COnfidence LeYel;

TU (Upper)

97.460

Natural Log

0.99%

Parameter Code;

01022

Data Transformation:

None

Parameter Name;

Boron, Tot

Confidence Level:

0.99%

~

mg/L

Pooled Results:

Normal

Mean

StdDev

K

Value

TU (Upper)

Yes

0.120

0.035

2.729

0.216

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

MANAGES

---

March 3, 2008

4:04:20 PM

Hutsonville Ash Impoundment

Normal Tolerance Interval on Background

Background Data Pool

Background Date Range:

Compliance Date Range:

Compliance Locations:

Background Locations:

09/0112002

to

03/3112005

0110112008

to

0110112008

Null

MWI,MWIO

Tolerance Coverage (Gamma):

Option for LT Pts:

95%

112

PQL (MOL

* 10/3)

BACKGROUND

Parameter Code;

01055

Parameter Name:

Manganese, Tot

mglL

Pooled Results:

~~----~~-.-

Data Transformation;

Confidence Leyel:

Natural Log

0.99%

Normal

Yes

0.071

StdDev

0.090

K Value

2.729

TU (Upper)

1.869

Parameter Code;

70300

Data Transformation;

None

Parameter Name;

TDS

Confidence Level;

0.99%

!lJlin;.

mglL

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

340.909

82.572

2.729

566.259

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

MANAGES

2

---

Hutsonville Ash Impoundment

Normal Tolerance Interval on Background

Background Data Pool

March 3, 2008

4:04:20 PM

Background Date Range:

Compliance Date Range:

Compliance Locations:

Background Locations:

BACKGROUND

09/0112002 to

03/3112005

0110112008 to 0110112008

Null

MW1,MWI0

Tolerance Coverage (Gamma):

Option for LT Pts:

95%

112 PQL (MOL

*

10/3)

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

MANAGES

3

---

March 3, 2008

Appendix B3: Tolerance Interval Calculation Background (Deep)

Compliance Date Range: 01/01/2008 to 01/01/2008

0.01

0

95%

Interwell

Background Locations:

MW121,MW7D

Background Date Range: 09/01/2002 to 03/31/2005

4:07:51 PM

Comparison Method if all Background Results are Non-Detect:

STmdl = Last MDL

Statistical Test for Parametric Background Data Distributions:

STpar = Parametric Tolerance Interval on Background

Statistical Test for Cases with High Percentage of Non-Detect Background Data:

Statistical Test for Cases with High Percentage of Non-Detect Background Data:

STnon = Non-Parametric Tolerance Interval on background

STlow1 = Non-Parametric Tolerance Interval on background (ND Frequency > 50%)

Background Comparison:

Number of Verification Samples:

Default Type 1 Individual Comparison Error Level

(False Positive Rate) for tests other than Prediction Interval

Non-Detect Processing (Parametric Tests):

Tolerance Interval Coverage:

Compliance Locations:

Null

Non-Detect Processing (All Other):

<=15% using 1/2 PQL (MDL * 10/3)

>15% using Cohen's Adj.

<=50% using MDL * 1.0

>50% using MDL * 1.0

Statistical Test for Non-Parametric Background Data Distributions:

STlow2 = Non-Parametric Tolerance Interval on background (ND Frequency > 50%)

---

Compliance

Normal /

Percent

of Non

detects

Count

Of Bkg

Results

Confidence

Location

Parameter

Sample Date

Lognormal

Test

Level

Upper Limit

Lower Limit

Analysis Result Exceedance Trend

01/01/2008

Null

Boron, Tot, mg/L

22

0.00

No/Yes

STpar

99.00

0.274

0.000

No

01/01/2008

Null

Manganese, Tot,

22

0.00

No/Yes

STpar

0.000

No

mg/L

99.00

2.369

01/01/2008

Null

pH (field), std

22

0.00

Yes/Yes

STpar

99.00

7.845

6.974

0.000

Yes

01/01/2008

Null

Sulfate, Tot, mg/L

22

0.00

Yes/Yes

STpar

99.00

84.303

0.000

No

01/01/2008

Null

TDS, mg/L

22

0.00

Yes/Yes

STpar

99.00

499.886

0.000

No

MANAGES

2

---

March 3, 2008

4:07:51 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW121,MW7D

COMPLIANCE

Location

Type

Class

Null

Parameter Name:

Parameter Code:

Units:

00400

pH (field)

Sample

Sample

Greater than

Lower than

Date

Result

TL (Upper)

TL (Lower)

Data Transformation:

None

Confidence Level:

0.99%

std

TL (Upper) Value

TL (Lower) Value

7.8

7.0

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Y

Parameter Name:

Parameter Code:

Units:

00945

Sulfate, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

84.3

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

01022

Boron, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

Natural Log

Confidence Level:

0.99%

mg/L

TL (Upper) Value

0.3

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

1

Lower Limit only listed for two sided test.

---

March 3, 2008

4:07:51 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW121,MW7D

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

01055

Manganese, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

Natural Log

Confidence Level:

0.99%

mg/L

TL (Upper) Value

2.4

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

70300

TDS

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

499.9

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

2

Lower Limit only listed for two sided test.

---

March 3, 2008

4:07:51 PM

Hutsonville Ash Impoundment

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Background Data Pool

Option for LT Pts:

1/2 PQL (MDL * 10/3)

95%

Background Locations:

MW121,MW7D

BACKGROUND

Location

Type

Total Pts

LT Pts

% LT Pts

Pooled

Alluvial Aq.

22

0

0

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TL (Lower)

TU (Upper)

Yes

7.410

0.141

00400

pH (field)

std

3.078

6.974

7.845

Data Transformation:

None

Confidence Level:

0.99%

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

43.818

14.834

00945

Sulfate, Tot

mg/L

2.729

84.303

Data Transformation:

None

Confidence Level:

0.99%

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

0.104

0.044

01022

Boron, Tot

mg/L

2.729

0.274

Data Transformation:

Natural Log

Confidence Level:

0.99%

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

MANAGES

1

---

March 3, 2008

4:07:51 PM

Hutsonville Ash Impoundment

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Background Data Pool

Option for LT Pts:

1/2 PQL (MDL * 10/3)

95%

Background Locations:

MW121,MW7D

BACKGROUND

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

0.930

0.385

01055

Manganese, Tot

mg/L

2.729

2.369

Data Transformation:

Natural Log

Confidence Level:

0.99%

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

354.091

53.422

70300

TDS

mg/L

2.729

499.886

Data Transformation:

None

Confidence Level:

0.99%

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

MANAGES

2

---

March 3, 2008

4:07:51 PM

Hutsonville Ash Impoundment

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Background Data Pool

Option for LT Pts:

1/2 PQL (MDL * 10/3)

95%

Background Locations:

MW121,MW7D

BACKGROUND

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

MANAGES

3

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW11R

pH (field), std

Data passed the W-test for normality

T Critical of all data: Tcr = 0.597

Test Statistic, high extreme of all data: Tn = 0.000

Test Statistic, low extreme of all data: T1 = 0.583

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW14

pH (field), std

Data failed to pass the W-test as either a normal or a lognormally distributed data set

Data is neither normally or lognormally distributed.

T Critical of all data: Tcr = 0.000

Test Statistic, high extreme of all data: Tn = 0.000

Test Statistic, low extreme of all data: T1 = 0.000

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW6

pH (field), std

Data passed the W-test for normality

T Critical of all data: Tcr = 0.597

Test Statistic, high extreme of all data: Tn = 0.286

Test Statistic, low extreme of all data: T1 = 0.000

No Outliers

1

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7

pH (field), std

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.560

Test Statistic, low extreme of all data: T1 = 0.360

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW8

pH (field), std

Data failed to pass the W-test as either a normal or a lognormally distributed data set

Data is neither normally or lognormally distributed.

T Critical of all data: Tcr = 0.000

Test Statistic, high extreme of all data: Tn = 0.000

Test Statistic, low extreme of all data: T1 = 0.000

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW11R

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.308

Test Statistic, low extreme of all data: T1 = 0.667

No Outliers

2

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW14

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.200

Test Statistic, low extreme of all data: T1 = 0.545

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW6

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.333

Test Statistic, low extreme of all data: T1 = 0.556

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.111

Test Statistic, low extreme of all data: T1 = 0.400

No Outliers

3

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW8

Sulfate, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.091

Test Statistic, low extreme of all data: T1 = 0.500

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW11R

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.269

Test Statistic, low extreme of all data: T1 = 0.045

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW14

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.364

Test Statistic, low extreme of all data: T1 = 0.314

No Outliers

4

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW6

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.200

Test Statistic, low extreme of all data: T1 = 0.412

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.333

Test Statistic, low extreme of all data: T1 = 0.650

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW8

Boron, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.333

Test Statistic, low extreme of all data: T1 = 0.333

No Outliers

5

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW11R

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.805

Test Statistic, low extreme of all data: T1 = 0.083

09/19/2002

3.400

False

1

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW14

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.154

Test Statistic, low extreme of all data: T1 = 0.375

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW6

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.640

Test Statistic, low extreme of all data: T1 = 0.045

No Outliers

6

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.495

Test Statistic, low extreme of all data: T1 = 0.054

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW8

Manganese, total, mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.423

Test Statistic, low extreme of all data: T1 = 0.360

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW11R

Total Filterable Residue (TDS), mg/L

Data failed to pass the W-test as either a normal or a lognormally distributed data set

Data is neither normally or lognormally distributed.

T Critical of all data: Tcr = 0.000

Test Statistic, high extreme of all data: Tn = 0.000

Test Statistic, low extreme of all data: T1 = 0.000

No Outliers

7

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW14

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.222

Test Statistic, low extreme of all data: T1 = 0.708

03/18/2003

570.000

False

-1

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW6

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.048

Test Statistic, low extreme of all data: T1 = 0.500

No Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW7

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.185

Test Statistic, low extreme of all data: T1 = 0.475

No Outliers

8

MANAGES

Based on Dixons one-sided outlier test

---

03/03/2008

3:52:06PM

Hutsonville Ash Impoundment

Date Range: 09/01/2002 to 03/31/2005

Confidence Level: 99%

LT Multiplier: x 1.0

Dixons Outlier Analysis Results - Downgradient Wells

Number of Outliers: First 10% Outliers

Sample Date

Value

LT_Value

Outlier

Low Side

Outlier

High Side

Location: MW8

Total Filterable Residue (TDS), mg/L

Data passed the W-test for normality

T Critical of all data: Tcr = 0.679

Test Statistic, high extreme of all data: Tn = 0.000

Test Statistic, low extreme of all data: T1 = 0.500

No Outliers

9

MANAGES

Based on Dixons one-sided outlier test

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Compliance Locations:

MW11R,MW14,MW6,MW7,MW8

Background Locations:

Compliance Analysis

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

00400

pH (field)

std

Two-Sided Interval

Confidence Level, %

One-Sided

TU (Upper) Value

TL (Lower) Value

Confidence Level, %

40.13

8.61

7.200

6.000

Background Sample Count:

10

Location

Sample

Sample

Greater than Lower than

Type

Class

Date

Result

TU (Upper)

TL (Lower)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW11R

Upper Zone

Downgradient

01/01/2008

7.000

N

N

Parameter Name:

Parameter Code:

Units:

00945

Sulfate, Tot

mg/L

One-Sided

TU (Upper) Value

Confidence Level, %

43.12

720.000

Background Sample Count:

11

Location

Sample

Sample

Greater than

Type

Class

Date

Result

TU (Upper)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW11R

Upper Zone

Downgradient

01/01/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

70300

TDS

mg/L

One-Sided

TU (Upper) Value

Confidence Level, %

43.12

1,300.000

Background Sample Count:

11

Location

Sample

Sample

Greater than

Type

Class

Date

Result

TU (Upper)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW11R

Upper Zone

Downgradient

01/01/2008

0.000

N

MANAGES

1

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Compliance Locations:

MW11R,MW14,MW6,MW7,MW8

Background Locations:

Compliance Analysis

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

00400

pH (field)

std

Two-Sided Interval

Confidence Level, %

One-Sided

TU (Upper) Value

TL (Lower) Value

Confidence Level, %

43.12

10.19

7.345

6.800

Background Sample Count:

11

Location

Sample

Sample

Greater than Lower than

Type

Class

Date

Result

TU (Upper)

TL (Lower)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW14

Alluvial Aq.

Downgradient

01/01/2008

7.000

N

N

Parameter Name:

Parameter Code:

Units:

70300

TDS

mg/L

One-Sided

TU (Upper) Value

Confidence Level, %

43.12

830.000

Background Sample Count:

11

Location

Sample

Sample

Greater than

Type

Class

Date

Result

TU (Upper)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW14

Alluvial Aq.

Downgradient

01/01/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

01055

Manganese, Tot

mg/L

One-Sided

TU (Upper) Value

Confidence Level, %

43.12

3.600

Background Sample Count:

11

Location

Sample

Sample

Greater than

Type

Class

Date

Result

TU (Upper)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW6

Upper Zone

Downgradient

01/01/2008

0.000

N

MANAGES

2

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Compliance Locations:

MW11R,MW14,MW6,MW7,MW8

Background Locations:

Compliance Analysis

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

01022

Boron, Tot

mg/L

One-Sided

TU (Upper) Value

Confidence Level, %

43.12

2.600

Background Sample Count:

11

Location

Sample

Sample

Greater than

Type

Class

Date

Result

TU (Upper)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW7

Upper Zone

Downgradient

01/01/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

00400

pH (field)

std

Two-Sided Interval

Confidence Level, %

One-Sided

TU (Upper) Value

TL (Lower) Value

Confidence Level, %

43.12

10.19

7.440

6.900

Background Sample Count:

11

Location

Sample

Sample

Greater than Lower than

Type

Class

Date

Result

TU (Upper)

TL (Lower)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW8

Upper Zone

Downgradient

01/01/2008

7.000

N

N

Parameter Name:

Parameter Code:

Units:

70300

TDS

mg/L

One-Sided

TU (Upper) Value

Confidence Level, %

43.12

1,800.000

Background Sample Count:

11

Location

Sample

Sample

Greater than

Type

Class

Date

Result

TU (Upper)

Tolerance Coverage Gamma:

95%

Option for LT Pts.:

MDL * 1.0

MW8

Upper Zone

Downgradient

01/01/2008

0.000

N

MANAGES

3

---

March 3, 2008

Appendix C2: Tolerance Interval Calculation

Compliance Date Range: 01/01/2008 to 01/01/2008

0.01

0

95%

Intrawell

Background Locations:

MW11R,MW14,MW6,MW7,MW8

Background Date Range: 09/01/2002 to 03/31/2005

3:57:52 PM

Comparison Method if all Background Results are Non-Detect:

STmdl = Last MDL

Statistical Test for Parametric Background Data Distributions:

STpar = Parametric Tolerance Interval on Background

Statistical Test for Cases with High Percentage of Non-Detect Background Data:

Statistical Test for Cases with High Percentage of Non-Detect Background Data:

STnon = Non-Parametric Tolerance Interval on background

STlow1 = Non-Parametric Tolerance Interval on background (ND Frequency > 50%)

Background Comparison:

Number of Verification Samples:

Default Type 1 Individual Comparison Error Level

(False Positive Rate) for tests other than Prediction Interval

Non-Detect Processing (Parametric Tests):

Tolerance Interval Coverage:

Compliance Locations:

MW11R,MW14,MW6,MW7,MW8

Non-Detect Processing (All Other):

<=15% using 1/2 PQL (MDL * 10/3)

>15% using Cohen's Adj.

<=50% using MDL * 1.0

>50% using MDL * 1.0

Statistical Test for Non-Parametric Background Data Distributions:

STlow2 = Non-Parametric Tolerance Interval on background (ND Frequency > 50%)

---

Compliance

Normal /

Percent

of Non

detects

Count

Of Bkg

Results

Confidence

Location

Parameter

Sample Date

Lognormal

Test

Level

Upper Limit

Lower Limit

Analysis Result Exceedance Trend

01/01/2008

MW11R

Boron, Tot, mg/L

11

0.00

Yes/Yes

STpar

99.00

11.582

0.000

No

01/01/2008

MW11R

Manganese, Tot,

11

0.00

No/Yes

STpar

0.000

No

mg/L

99.00

9.499

01/01/2008

MW11R

pH (field), std

10

0.00

No/No

STnon

40.13

7.200

6.000

7.000

No

01/01/2008

MW11R

Sulfate, Tot, mg/L

11

0.00

No/No

STnon

43.12

720.000

0.000

No

01/01/2008

MW11R

TDS, mg/L

11

0.00

No/No

STnon

43.12

1,300.000

0.000

No

MANAGES

2

---

Compliance

Normal /

Percent

of Non

detects

Count

Of Bkg

Results

Confidence

Location

Parameter

Sample Date

Lognormal

Test

Level

Upper Limit

Lower Limit

Analysis Result Exceedance Trend

01/01/2008

MW14

Boron, Tot, mg/L

11

0.00

Yes/Yes

STpar

99.00

2.285

0.000

No

01/01/2008

MW14

Manganese, Tot,

11

0.00

Yes/Yes

STpar

0.000

No

mg/L

99.00

0.668

01/01/2008

MW14

pH (field), std

11

0.00

No/No

STnon

43.12

7.345

6.800

7.000

No

01/01/2008

MW14

Sulfate, Tot, mg/L

11

0.00

Yes/No

STpar

99.00

305.104

0.000

No

01/01/2008

MW14

TDS, mg/L

11

0.00

No/No

STnon

43.12

830.000

0.000

No

MANAGES

3

---

Compliance

Normal /

Percent

of Non

detects

Count

Of Bkg

Results

Confidence

Location

Parameter

Sample Date

Lognormal

Test

Level

Upper Limit

Lower Limit

Analysis Result Exceedance Trend

01/01/2008

MW6

Boron, Tot, mg/L

11

0.00

Yes/Yes

STpar

99.00

21.457

0.000

No

01/01/2008

MW6

Manganese, Tot,

11

0.00

No/No

STnon

0.000

No

mg/L

43.12

3.600

01/01/2008

MW6

pH (field), std

10

0.00

Yes/Yes

STpar

99.00

7.870

6.072

7.000

No

01/01/2008

MW6

Sulfate, Tot, mg/L

11

0.00

Yes/Yes

STpar

99.00

575.634

0.000

No

01/01/2008

MW6

TDS, mg/L

11

0.00

Yes/Yes

STpar

99.00

1,127.593

0.000

No

MANAGES

4

---

Compliance

Normal /

Percent

of Non

detects

Count

Of Bkg

Results

Confidence

Location

Parameter

Sample Date

Lognormal

Test

Level

Upper Limit

Lower Limit

Analysis Result Exceedance Trend

01/01/2008

MW7

Boron, Tot, mg/L

11

0.00

No/No

STnon

43.12

2.600

0.000

No

01/01/2008

MW7

Manganese, Tot,

11

0.00

No/Yes

STpar

0.000

No

mg/L

99.00

1.749

01/01/2008

MW7

pH (field), std

11

0.00

Yes/Yes

STpar

99.00

7.528

6.394

7.000

No

01/01/2008

MW7

Sulfate, Tot, mg/L

11

0.00

Yes/Yes

STpar

99.00

415.575

0.000

No

01/01/2008

MW7

TDS, mg/L

11

0.00

Yes/Yes

STpar

99.00

1,262.269

0.000

No

MANAGES

5

---

Compliance

Normal /

Percent

of Non

detects

Count

Of Bkg

Results

Confidence

Location

Parameter

Sample Date

Lognormal

Test

Level

Upper Limit

Lower Limit

Analysis Result Exceedance Trend

01/01/2008

MW8

Boron, Tot, mg/L

11

0.00

Yes/Yes

STpar

99.00

16.215

0.000

No

01/01/2008

MW8

Manganese, Tot,

11

0.00

Yes/Yes

STpar

0.000

No

mg/L

99.00

6.136

01/01/2008

MW8

pH (field), std

11

0.00

No/No

STnon

43.12

7.440

6.900

7.000

No

01/01/2008

MW8

Sulfate, Tot, mg/L

11

0.00

Yes/Yes

STpar

99.00

1,240.719

0.000

No

01/01/2008

MW8

TDS, mg/L

11

0.00

No/No

STnon

43.12

1,800.000

0.000

No

MANAGES

6

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

COMPLIANCE

Location

Type

Class

MW11R

Upper Zone

Downgradient

Parameter Name:

Parameter Code:

Units:

01022

Boron, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

11.6

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

01055

Manganese, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

Natural Log

Confidence Level:

0.99%

mg/L

TL (Upper) Value

9.5

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Location

Type

Class

MW14

Alluvial Aq.

Downgradient

Parameter Name:

Parameter Code:

Units:

00945

Sulfate, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

305.1

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

1

Lower Limit only listed for two sided test.

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

01022

Boron, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

2.3

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

01055

Manganese, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

0.7

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Location

Type

Class

MW6

Upper Zone

Downgradient

Parameter Name:

Parameter Code:

Units:

00400

pH (field)

Sample

Sample

Greater than

Lower than

Date

Result

TL (Upper)

TL (Lower)

Data Transformation:

None

Confidence Level:

0.99%

std

TL (Upper) Value

TL (Lower) Value

7.9

6.1

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

7.000

N

N

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

2

Lower Limit only listed for two sided test.

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

00945

Sulfate, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

575.6

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

01022

Boron, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

21.5

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

70300

TDS

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

1,127.6

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Location

Type

Class

MW7

Upper Zone

Downgradient

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

3

Lower Limit only listed for two sided test.

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

00400

pH (field)

Sample

Sample

Greater than

Lower than

Date

Result

TL (Upper)

TL (Lower)

Data Transformation:

None

Confidence Level:

0.99%

std

TL (Upper) Value

TL (Lower) Value

7.5

6.4

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

7.000

N

N

Parameter Name:

Parameter Code:

Units:

00945

Sulfate, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

415.6

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

01055

Manganese, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

Natural Log

Confidence Level:

0.99%

mg/L

TL (Upper) Value

1.7

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

4

Lower Limit only listed for two sided test.

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

70300

TDS

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

1,262.3

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Location

Type

Class

MW8

Upper Zone

Downgradient

Parameter Name:

Parameter Code:

Units:

00945

Sulfate, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

1,240.7

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Parameter Name:

Parameter Code:

Units:

01022

Boron, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

16.2

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

5

Lower Limit only listed for two sided test.

---

March 3, 2008

3:57:52 PM

Hutsonville Ash Impoundment

User Supplied Information

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Compliance Analysis

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

COMPLIANCE

Parameter Name:

Parameter Code:

Units:

01055

Manganese, Tot

Sample

Sample

Greater than

Date

Result

TL (Upper)

Data Transformation:

None

Confidence Level:

0.99%

mg/L

TL (Upper) Value

6.1

Option for LT Pts.:

1/2 PQL (MDL *

10/3)

1/1/2008

0.000

N

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

When "Greater than TL (Upper)" is Y, this indicates statistical evidence of exceedance of the upper tolerance limit.

MANAGES

6

Lower Limit only listed for two sided test.

---

March 3, 2008

3:57:51 PM

Hutsonville Ash Impoundment

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Background Data Pool

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

BACKGROUND

Location

Type

MW11R

Upper Zone

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

5.109

1.817

01022

Boron, Tot

mg/L

3.563

11.582

Data Transformation:

None

Confidence Level:

0.99%

Total Pts LT Pts % LT Pts

11

0

0

Option for LT Pts.:

1/2 PQL (MDL * 10/3)

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

0.850

0.896

01055

Manganese, Tot

mg/L

3.563

9.499

Data Transformation:

Natural Log

Confidence Level:

0.99%

Total Pts LT Pts % LT Pts

11

0

0

Option for LT Pts.:

1/2 PQL (MDL * 10/3)

Note: Confidence Level is sometimes referred to as Tolerance Coefficient.

MANAGES

1

---

March 3, 2008

3:57:51 PM

Hutsonville Ash Impoundment

Background Date Range:

09/01/2002 to 03/31/2005

Compliance Date Range:

01/01/2008 to 01/01/2008

Tolerance Coverage (Gamma):

Compliance Locations:

Background Data Pool

95%

Background Locations:

MW11R,MW14,MW6,MW7,MW8

BACKGROUND

Location

Type

MW14

Alluvial Aq.

Parameter Code:

Parameter Name:

Units:

Pooled Results:

Normal

Mean

StdDev

K Value

TU (Upper)

Yes

195.455

30.778