2023 CCR Impoundment Annual Groundwater Report by cityofindepmo

Technical Memorandum To: Eric Holder, Independence Power & Light From: Andrea Collier and Tony Schroer, Barr Engineering Co. Subject: 2023 Blue Valley Facility CCR Impoundment Groundwater Monitoring Report Date: February 2024 Project: 25491019.01 c: James Barry, Independence Power & Light Rob Morrison, Barr Engineering Co.

1.0

Introduction

On behalf of the Independence Power and Light (IPL), Barr Engineering Co. (Barr) has prepared this 2023 Groundwater Monitoring Report for the IPL Blue Valley Power Plant Facility located at 21500 East Truman Road in Independence, Missouri (Site) (Figure 1 in Attachment A).

Project activities conducted in March and June 2023 included routine groundwater monitoring and well

inspections. This report presents the field data and analytical results for all Quarterly 2023 monitoring events. 1.1

Site Background

The Facility was constructed in 1958 as a tri-fuel steam electric power plant that burned coal, diesel, and natural gas until 2015, when it ceased power production from coal and diesel and was converted to a

natural gas facility. Two of the original CCR impoundments, the south fly ash pond, and bottom ash pond

were built in 1978. The north fly ash pond was constructed in 1989. The Facility sluiced bottom ash and fly ash into the ponds until 2015. Upon the discontinuation of ash sluicing into the CCR impoundments,

the former impoundments became “inactive surface impoundments” subject to the requirements of the Federal CCR Rule, 40 CFR 257.100, Subpart D. The Notice of Closure Completion for all three former

impoundments was submitted to MDNR on December 19, 2017.

The Site is located approximately seven miles south of the Missouri River in the north central portion of

Jackson County at 21500 East Truman Road in Independence, Missouri in Section 3, Township 49N, and Range 31W. Figure 2 displays the Site location and impoundment boundary. The Site is located within

the Central Irregular Plains Ecoregion of west central Missouri. Potential natural vegetation of this

ecoregion includes a mix of grassland and forest, with forested areas particularly located along streams

(Purdue, 2020). Land use adjacent to the Site, displayed on Figure 2 (Attachment A), is primarily industrial and agricultural, with industries located north, south, and west of the Site and agricultural land located to the east. An isolated residential area is also located north of the Site.

Regional topography is characterized by hills and associated dendritic drainage patterns with

approximately 150 feet of relief within one mile of the Site. Hills north and west of the Facility have

Barr Engineering Co. 1001 Diamond Ridge, Suite 1100, Jefferson City, MO 65109 573.638.5000 www.barr.com

To: Eric Holder, Independence Power & Light From: Andrea Collier and Andrea Collier and Tony Schroer, Barr Engineering Co. Subject: 2023 Blue Valley Facility CCR Impoundment Groundwater Monitoring Report Date: February 2024 Page: 2

elevations as high as 900 feet above mean sea level (MSL). The Site has features with elevations that

range from approximately 750 to 800 feet above MSL and slope from the northwest to southeast (Figure 1 in Attachment A). A topographic divide, located in the southwest portion of the Site, separates the Little Blue River and Burr Oak-Creek-Little Blue River subwatersheds (Hydrologic Unit Code 12). 1.2

Regional Geology

The surficial soils of the region and portions of the Site outside the former impoundments consist

primarily of unconsolidated alluvial sediments known as the Sibley Silt Loam series. According to the Soil Survey of Jackson County, Missouri (1984) developed by the United States Department of Agriculture

(USDA), the Sibley Silt Loam is a friable, moderate permeability soil with naturally high fertility (USDA,

1984). The surface layer is generally dark brown, the middle sections can be dark brown to grey, and the lower sections are generally more clayey and dark yellowish-brown with various mottles.

Based on the report, City of Independence, Missouri, Blue Valley Generating Station Ash Pond Addition and Other Improvements (Burns and McDonnell, 1977), the subsurface soil in the proximity of the former

impoundments consists primarily of silty clay with interbedded seams of fine-grained, uncompacted

sandy silt. The report provides descriptive logs for 27 borings drilled in a grid pattern encompassing the

area of the former fly ash and bottom ash ponds. The borings ranged in depth from 10 feet to 64 feet bgs.

The bedrock underlying the region and Site consists of Pennsylvanian aged shales, limestones, sandstone, and siltstones with interbedded coal seams. Naturally occurring crude oil was identified in upgradient

borings during the Site Characterization performed in 2020. The Pennsylvanian-aged shales overly older Mississippian aged formations (MDNR, 1997).

The Pennsylvanian-aged Pleasanton Group is the first bedrock unit encountered in the region, located

approximately 25 feet bgs. The Pleasanton Group is predominantly a thick unit of shale with limestone and a basal unit of siltstone or very fined-grained sandstone. Two additional sandstone units, which

combined are known as the Warrensburg Sandstone, are sometimes present in the upper half of the

group depending on the location. The base of the Pleasanton Group marks a break in the depositional

sequence occurring in the Pennsylvanian time. This break in the depositional sequence forms a regional disconformity. Underlying the Pleasanton Group bedrock unit is the Marmaton Group. The Marmaton Group is comprised mainly of thick shales with intervening thin layers of limestone and sandstone. 1.3

Regional Hydrogeology

The hydrogeology around the Site is represented by the Missouri River alluvium and Lake City alluvium,

two groundwater subprovinces of the West-Central groundwater province. The Site is primarily located

within the Missouri River alluvium, which borders the Lake City alluvium just east of the Site near the Little Blue River. Information describing the West-Central groundwater province and each subprovince is provided below.

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The West-Central groundwater province is bounded by the Missouri River to the north, the Springfield

Plateau groundwater province to the south and east, and the Kansas state boundary to the west. The greatest potential for groundwater yield within this province is from the alluvial deposits along the

northern edge of the province, which include the Missouri River alluvium and Lake City alluvium, further

described below. Pennsylvanian-aged formations comprise the bedrock surface units for most of this

groundwater province, specifically the Pleasanton and Marmaton Groups in the area of the Site. The

Pleasanton and Marmaton Groups in the region have low recharge potential due to their extremely low

horizontal and vertical permeabilities and are not considered to be water bearing; the Pleasanton Group is considered to be less productive than the Marmaton Group (MDNR, 2021). Of the small amounts of

groundwater that may potentially be drawn from these groups, the groundwater is expected to be of poor quality.

The Missouri River alluvium province is located at the northern portion of the West-Central groundwater

province and extends for the entire length of the Missouri River throughout the state with an aerial extent of approximately 440 square miles in the vicinity of the Site. The Missouri River alluvium formed from

glacial meltwater runoff during the Pleistocene epoch (Ice Age); the melt water transported a significant amount of sediments that ranged in size from clay particles to boulders, which carved a river channel

much wider than the channel occupied by the Missouri River today. Following the Pleistocene epoch, over-bank flooding of present-day rivers has deposited additional alluvium on river floodplains. The

Missouri River and the Missouri River alluvium province experience delayed recharge; studies of wells

within the alluvium indicated a delayed response of several days between river stages and groundwater levels. Under normal flow conditions in the Missouri River, groundwater gradients in the Missouri River alluvium are toward the river (MDNR, 1997).

In the report Groundwater Resources of Missouri (MDNR, 1997), the Missouri River alluvium is divided into

four segments from the Iowa border to St. Charles, prior to the Missouri River and Mississippi River

confluence. For the purpose of this project, the portion of the Missouri River alluvium province discussed

in this section is the Kansas City to Miami, Missouri segment. The Missouri River alluvium in this segment composed primarily of fine sand, silt, and clay with coarse sands and gravels comprising the deeper

portions of the alluvium. The alluvium has a maximum thickness of 140 feet and an average thickness of 85 to 90 feet. The average saturated thickness of the alluvium is approximately 75 feet for this area.

Groundwater from wells within the Missouri River alluvium supplies a majority of the potable water in the Kansas City area. Yields from the Missouri River alluvium may reach 1,000 to 1,500 gallons per minute (gpm) in the more permeable areas of the alluvium (MDNR, 1997).

The Lake City alluvium groundwater subprovince is a 16-mile-long, 1-2-mile-wide channel that begins at the southern edge of the Missouri River alluvium in central Jackson County near the town of Atherton,

extends southeast to Lake City, and then trends northeast until it again intersects with the Missouri River alluvium in northeastern Jackson County near the town of Levasy. The Lake City alluvial channel likely

formed as a result of an ice damming event on the ancestral Missouri River, which forced the river south

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of the existing channel and eroded the new channel, which currently serves as the river valley for the Little Blue River from Lake City to the Missouri River. The Site is located on the western edge of the Lake City alluvium channel. A study of this alluvium aquifer at the Lake City Army Ammunition Plant in the early

1940s estimated the alluvium’s thickness to 80 to 90 feet with a depth to water of 15 to 20 feet bgs. Well pumping rates during this study reached 300 to 400 gpm (MDNR, 1997).

2.0

Hydrogeologic Data and Monitoring

Hydrogeologic monitoring at the Site includes the collection of groundwater elevation data from Site

monitoring wells. The monitoring well locations at the Site are shown on Figure 3 (Attachment A) and well construction information is located in Table 1 (Attachment B). 2.1

Potentiometric Surface Measurements

During the two Quarterly 2023 monitoring events, water-levels were collected from the eight (8) routinely scheduled groundwater monitoring wells. The resultant elevation data were used to develop

potentiometric surface flow maps, assess flow direction, and calculate gradients for the shallow

groundwater. A summary of all groundwater elevation data is included as Table 2 (Attachment B). 2.2

Groundwater Flow Direction and Gradient

The groundwater elevation data from the Site’s shallow monitoring wells were contoured to construct potentiometric surface maps for each quarterly event. As graphically illustrated on Figures 4 and 5

groundwater flows generally towards the east which is consistent with historic water elevation data for the Site.

The calculated hydraulic gradient for each of the Quarterly 2023 monitoring events is provided below: Hydraulic Gradient North Side (West) (MW-6 to MW-8)

North Side (East) (MW-8 to MW-1)

March 2023

0.002

June 2023

0.003

0.004

Monitoring Event

East Side (MW-6 to MW-1)

Hydraulic gradients measured across the Site range from 0.002 to 0.004 (range for gradients from three

different areas of the Site) for the Quarterly 2023 groundwater elevation data (Table 2 -Attachment B). The hydraulic gradient measured across the northwestern portion of the Site (MW-6 to MW-8) was

calculated to be -0.002 for March 2023 and 0.003 for June 2023. The hydraulic gradient measured across

the northeastern portion of the Site (MW-1 to MW-8) was calculated to be 0.002 for March 2023 and

0.003 for June 2023. The hydraulic gradient measured across the central portion of the Site (MW-6 to

MW-1) was calculated to be -0.00009 for March 2023 and 0.004 for June 2023. It should be noted that

water levels measured in the upgradient wells may not be representative of actual static water levels since stabilization subsequent to purging can take several weeks. The water level measured for MW-6 during

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the March sampling event was not utilized for hydraulic gradient measurements because the water level had not fully re-stabilized and resulted in hydraulic gradients inconsistent with the general groundwater flow.

The average hydraulic gradient is towards the east with a slope of approximately 0.0008 for March and 0.003 for June across the entire Site. This slope is relatively shallow as compared to previous years

(particularly for the March event) likely due to the varying water elevations in the upgradient monitoring

wells. An approximate average interstitial velocity across the Site has been estimated to range from 1.3 x

10-3 feet/day to 3.6 x 10-4 feet/day (i.e. 0.48 to 0.13 feet/year) for March 2023 and 4.7 x 10-3 feet/day to 1.3

x 10-3 feet/day (i.e. 1.7 to 0.5 feet/year) for June 2023 as calculated by the following equation and input

data:

v = Ki/n, where v = average interstitial velocity K = hydraulic conductivity (ranges from 0.388 to 0.171 feet/day) i = average hydraulic gradient across the Site (0.0008 and 0.003) n = effective porosity (estimated to range from 0.25 to 0.4) 2.3

Groundwater Hydrographs

Overall, groundwater elevations measured in wells during the two Quarters of 2023 monitoring events were relatively consistent with the data from the measurements taken during the previous sampling

events (Barr, 2022). Hydrographs of the groundwater elevations are provided in Attachment C

Due to the relatively higher recharge rates the downgradient well groundwater elevations have not

changed significantly from previous monitoring periods. The greatest variance of water level elevations

observed in the downgradient wells during 2023 is 1.75 feet in monitoring well MW-1. This groundwater elevation change represents measurements with seasonal flux and significantly drier/wetter periods.

The groundwater elevation fluctuations in the upgradient wells are significantly more prominent than the

changes observed in the downgradient wells, however this may be primarily due to the slow recharge

times of the upgradient wells. During several monitoring events the water levels measured immediately prior to sampling in the upgradient wells did not appear to be stabilized subsequent to purging. The

groundwater elevations for the upgradient wells have been observed to change up to 5.35 feet (MW-7)

between groundwater sampling events in 2023. It should be noted that the groundwater levels observed in MW-8 over the last eight quarterly monitoring events differs from the levels of the other wells. The

hydrograph for MW-8 indicates that since the first quarterly monitoring event the water levels in MW-8 have potentially not completely recovered after purging. The water levels for MW-8 during the second

through eighth quarterly events are on average 10 feet lower than the water level measured during the

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first quarterly event. Either MW-8 has been experiencing significantly reduced recharge for that time

period or the well has not been completely recharging between the quarterly sampling events. Groundwater levels for active monitoring wells are presented in Table 2 (Attachment B). 2.4 Groundwater Monitoring Network No modifications have been made to the monitoring network since well installation in 2019.

3.0

Groundwater Sampling and Field Activities

The field methods for the collection of the samples are described in the Groundwater Monitoring Sampling and Analysis Plan (GMSAP) (Barr, 2021). 3.1

Well Inspections

During the 2023 monitoring events, the sampling crew measured the static water levels in each of the

eight active monitoring wells at the site and visually inspected each well’s condition. Any evidence of well damage was documented in the field documents (Attachment D). Table 1 (Attachment B) contains a

summary of the monitoring well construction including well number designation, measured total depth, elevation for top of screen, and the measured static water level for each well. 3.2

Sample Collection

Groundwater samples were collected at two quarterly sampling events (March 2023 and June 2023) from

the eight active monitoring wells at the Site. Groundwater sampling was conducted using bailers and low

stress (low flow) methodology in compliance with the GMSAP (Barr, 2021). For the wells sampled via low

stress (low flow) methodology, a submersible pump was lowered into the well screen and pumped at the lowest possible rate until measurements of temperature, pH, specific conductivity, dissolved oxygen,

turbidity, and ORP stabilized. These parameters can be found on the field logs in Attachment D. The low

flow sampling was performed in compliance with Section 3.0, Section 4.0, and Appendix D of the GMSAP. For the wells sampled via bailers, the wells were purged at least three weeks prior to the sampling events. During the sampling event the bailers were extracted from the wells and the samples collected. Water

quality parameters were collected via bailer immediately subsequent to the sample collection.

For quality control (QC) purposes duplicate samples were collected during each sampling event. During both sampling events, duplicate samples were collected from downgradient well MW-5 for the March sampling event and MW-3 for the June sampling event.

4.0

Groundwater Analytical Results

4.1

March 2023

Groundwater samples were collected at all monitoring wells installed at the Site. Table 3 (Attachment B)

summarizes the groundwater concentration data from the wells and compares the concentrations against

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EPA’s MCLs (40 CFR 141.62 and 257.95). Groundwater samples from the March 2023 sampling event that exceeded EPA’s MCLs are shown on Figure 6 (Attachment A).

Groundwater concentration exceedances of the EPA MCLs for total arsenic and total/dissolved lithium were identified in some of the samples. The following list summarizes the exceedances for each constituent: •

Total arsenic: Groundwater concentrations exceeded the arsenic MCL of 10 µg/L at downgradient

monitoring wells MW-3, and MW-4. Total arsenic concentrations at the wells ranged from 26.8 to 35.3 µg/L; however, dissolved concentrations in these wells were all below 5 ug/L •

Total and dissolved lithium: Groundwater concentrations exceed the lithium MCL of 40 µg/L at

upgradient monitoring wells MW-6, MW-7, and MW-8. Total lithium concentrations at the wells

ranged from 46.8 to 111 µg/L. Dissolved lithium concentrations at the wells ranged from 48.5 to 141

µg/L. 4.2

June 2023

During the June 2023 sampling event, groundwater samples were collected from all eight monitoring

wells installed at the Site. Groundwater samples from the June 2023 sampling event that exceeded EPA’s

MCLs on Figure 5 (Attachment A).

Groundwater concentration exceedances of the EPA MCLs for total arsenic, total lead, and dissolved/total

lithium were identified in some of the samples in upgradient and downgradient wells. The following list

summarizes the exceedances for each constituent: •

Total arsenic: groundwater concentrations exceeded the arsenic MCL of 10 µg/L at downgradient

monitoring wells MW-1, MW-3, and MW-4. Total arsenic concentrations at these three wells ranged from 10.2 to 40.9 µg/L and dissolved concentrations were all below 5 ug/L.

•

Total and dissolved lithium: Groundwater concentrations exceed the lithium MCL of 40 µg/L at

upgradient monitoring wells MW-6, MW-7, and MW-8. The total lithium concentrations for wells MW6, MW-7, and MW-8 were 52.4, 42.9, and 100 µg/L respectively. The dissolved lithium concentrations

for wells MW-6, MW-7, and MW-8 were 50, 44.4, and 93.0 µg/L respectively. •

Total Lead: Groundwater concentrations exceeded the lead MCL of 15 µg/L at upgradient monitoring

well MW-6. The total lead concentration detected in monitoring well MW-6 is 16.3 µg/L.

5.0

Conclusions and Recommendations

The results of the 2023 groundwater sampling events at the Site have been summarized in the previous

sections and the conclusions and recommendations based on those results are outlined in the following paragraphs.

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5.1

Site Groundwater

Upgradient and downgradient groundwater sample concentrations indicate that the groundwater

contains metals concentrations. The metals concentrations for arsenic, lead, and lithium exceed the MCLs

in some of the upgradient and downgradient wells. As discussed in the Site Characterization Report (Barr, 2020), the native materials at the Site contain concentrations of metals that exceed the MRBCA Default

Target Levels and are naturally occurring metals in the native materials that are typically associated with CCR material. Therefore, the native soil around the former impoundments is likely to be a source for metals in the groundwater.

As a result, groundwater monitoring in compliance with the proposed GMSAP will be utilized to continue monitoring these and other parameters to identify their potential source, concentrations trends, and representativeness in the shallow groundwater as needed. 5.2

Groundwater Flow

Results of the Site Characterization Report (Barr, 2020) indicates that the shallow groundwater underlying

the site migrates slowly due to the fine-grained nature/low permeability of the unconsolidated units underlying the former impoundments.

The groundwater data continues to be consistent with previous observations made regarding

groundwater flow and direction. The groundwater flow at the Site is primarily to the east/southeast and groundwater underlying the former impoundments migrates primarily through the sand layers in the unconsolidated units.

Since groundwater contact with the impoundment material is limited, it is unlikely that leaching of metals from CCR materials is occurring via lateral groundwater movement through the former impoundment. In addition, to date, groundwater elevations measured from groundwater wells do not indicate that

groundwater is migrating through CCR materials in the northwest corner of the impoundment area. Therefore, the potential for COCs to migrate is primarily via vertical leaching of the low volumes of meteoric water that have infiltrated through the engineered cap. 5.3

Groundwater Statistical Analyses

In accordance with the requirements of the Federal coal combustion residual CCR rule, in 40 Code of

Federal Regulations (CFR) Part 257, Subpart D the groundwater monitoring data collected over the last

eight quarters was evaluated using statistical analysis. The conclusions of the statistical analysis are

presented below and in the Baseline Monitoring Statistical Summary Report (Barr, 2024).

Eight baseline samples were collected quarterly from September 2021 to June 2023 at eight monitoring

wells (MW-1 to MW-8). Monitoring wells MW-1 through MW-5 were installed downgradient of the Blue Valley CCR impoundments and monitoring wells MW-6 through MW-8 were installed upgradient of the Blue Valley CCR impoundments. Each sample was analyzed for the COPCs listed in Table 2 to establish baseline concentrations at the Site. This sampling parameter list was determined by the MSOP and

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incidentally included all Appendix III and IV constituents. Had IPL determined their sampling parameter list according to 257 Subpart D requirements the baseline sampling would have included only the

Appendix III constituents as no SSIs were detected in these eight monitoring events. Furthermore, the detection monitoring constituent boron, a relatively soluble metal, was detected at elevated

concentrations upgradient and downgradient of the impoundments These detections provide further

evidence to support the idea that native soils surrounding the impoundments are the primary source of metals concentrations in the groundwater.

Each constituent well pair was statistically evaluated for percent detection, normality, outliers, and trends to determine the appropriate method for establishing a comparison limit. Either control limits or NPPLs were calculated for each constituent well pair and are recorded in Table 4 and shown graphically in

Appendix F. Control limits or PPLs will not be used on the significantly trending data. Four well constituent pairs had significant increasing trends, and two well constituent pairs had significant decreasing trends. These well-constituent pairs will be monitored by comparing the slope magnitudes and Mann Kendall Statistic for worsening trends. All increasing trends were in upgradient wells.

The four significantly increasing trends were: • • • •

Barium at MW-7

Chloride at MW-8

Specific Conductance at MW-6 Sulfate at MW-6

The source of the increasing trends is not likely related to the CCR impoundments because the monitoring

wells are upgradient of the impoundments. In regard to the barium concentrations in MW-7, this

monitoring well is far upgradient of the impoundments and the site characterization investigation

identified constituents in the soils and bedrock that are likely part of the native materials and not from the impoundments. In addition, groundwater variations in specific conductance and sulfates can occur often and although they indicate changes in the groundwater geochemistry their location upgradient of the impoundments reduces the likelihood that they are a result of potential water interaction with

impoundment materials. There is likely spatial variation and natural variability at these monitoring wells. The upper control limits for pH at MW-6, MW-7, and MW-8 exceed pH values of water (14 s.u.) and is a result of the low number of sample points and the software utilized for the statistical evaluation. The upper control limits for pH at these wells has been manually adjusted to 14 s.u.

Future groundwater monitoring results will be used to assess the rate and extent of potential constituent

migration by comparing future results to the control limits or NPPLs established in this report. In addition, the four significantly increasing trends will be monitored to identify if an SSI occurs.

As no increasing trends were identified in the downgradient wells the data will be monitored to identify

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the Site Characterization Report indicated that the metals detected in the groundwater at the site are

consistent with native materials surrounding the impoundments. Constituents that are typically associated with CCR impoundments have been detected in upgradient wells in concentrations that are consistent with detections in downgradient wells. As such, an alternative source demonstration (ASD) has been determined to be currently unnecessary.

6.0

References

Barr, 2024. Blue Valley Coal Combustion Residuals Impoundment Baseline Monitoring Statistical

Summary Report, Independence Power and Light Blue Valley Power Plant, Independence, Missouri. February 2024.

Barr, 2021. Blue Valley Coal Combustion Residuals Impoundment Groundwater Monitoring Sampling and Analysis Plan, Independence Power and Light Blue Valley Power Plant, Independence, Missouri. July 2021.

Barr, 2020. Blue Valley Coal Combustion Residuals Impoundment Site Characterization Report,

Independence Power and Light Blue Valley Power Plant, Independence, Missouri. May 2020.

Burns and McDonnell, 1977. City of Independence, Missouri, Blue Valley Generating Station Ash Pond

Addition and Other Improvements, May 1977.

Freeze, R. A. and J. A. Cherry, 1979. Groundwater, Prentice-Hall, Inc., Englewood Cliffs, New Jersey, 604p. Missouri Department of Natural Resources, 2021. Geosciences Technical Resources Assessment Tool Website, URL: https://dnr.mo.gov/geology/geostrat.htm. Accessed January 2020. Missouri Department of Natural Resources Division of Geology and Land Survey, 1997. Groundwater Resources of Missouri, Don E. Miller, 1997.

Purdue University, 2020. Primary Distinguishing Characteristics of Level III Ecoregions of the Continental United States Website, URL: https://hort.purdue.edu/newcrop/cropmap/ecoreg/descript.html#40. Accessed July – September, 2019.

US Department of Agriculture, 1984. Soil Survey of Jackson County, Missouri. September 1984 Attachments Attachment A – Figures

Attachment B – Tables

Attachment C – Hydrographs

Attachment D – Field Data

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Attachment A Figures

Ja c ks o n C o u n t y

£ ¤ Un

HUC8: Lower Missouri-Crooked 10300101

na m ed

b Tr i

HUC12: Little Blue River 103001010208

ar ut

Perennial Stream or River

Li ttl e

Ri v

Intermittent Stream, River, or Wash

es t

Little B l u e Riv e r

re ri ai Pr

Property Boundary

HUC12 Watershed Boundary

k ee Cr 78

Wetlands (NWI)

Freshwater Emergent Wetland

Barr Footer: ArcGIS 10.7.1, 2020-04-10 09:33 File: I:\Projects\25\49\1019\Maps\Reports\Characterization_Report\Figure 1-1 Site Location.mxd User: MRQ

Freshwater Forested/ Shrub Wetland Freshwater Pond Other

S pring Branch

Riverine Cree k

HUC12: Burr Oak Creek-Little Blue River 103001010207

reek kC a O Bur r

; ! N

1,000

2,000

3,000

Feet

FIGURE 1

Barr Footer: ArcGIS 10.8.1, 2022-01-18 12:17 File: I:\Projects\25\49\1019\Maps\Reports\Federal_Groundwater_Tech_Memo\Figure 2 Site Layout.mxd User: MRQ

4TH ST

Earley Machine LLC

POWELL RD

Continental Manufacturing

n Pa Unio

Bottom Ash Impoundment (Closed)

Independence School District Transportation Complex

Clos ed

South Fly Ash Impoundment (Closed)

HEMCO Corporation

cific R

ailro

? !

LITTLE BLUE PKWY

North Fly Ash Impoundment (Closed)

Bottom Ash Impoundment (Clean Closure and Converted to a Sedimentation Basin)

? !

Midwest Directional Services

TRUMAN RD POWELL RD

RANSON PL

RANSON ST

Watco Manufacturing Co.

T 13TH

Barbour Concrete Company

Metal Sale Manufacturing Corporation

Closed Railroad Property Boundary

; ! N

Feet

450

Note: Property boundary obtained from Jackson County parcel dataset, MO GIS Department. Imagery: Nearmap, February 2020

SITE LAYOUT Independence Power & Light Independence, Missouri

FIGURE 2

Barr Footer: ArcGIS 10.8.1, 2022-09-21 11:17 File: I:\Projects\25\49\1019\Maps\Reports\MDNR Baseline Summary Report_2022\Figure 3 Monitoring Well Locations.mxd User: kac2

4TH ST

MW-8

! ?

MW-1

MW-6

! >

! ?

MW-2

MW-3

! >

LITTLE BLUE PKWY

! >

MW-7

! ?

MW-4

POWELL RD

Clos ed

Un i

on P a

cific

Rail ro

! >

MW-5

! >

POWELL RD

TRUMAN RD

Note: Property boundary obtained from Jackson County parcel dataset, MO GIS Department.

Imagery: Nearmap, September 2021

! > ! ?

Downgradient Monitoring Well Upgradient Monitoring Well Property Boundary Closed Railroad

; ! N

175

350

Feet

525

MONITORING WELL LOCATIONS Independence Power & Light Independence, Missouri FIGURE 3

BOBBY AVE

VALEEN AVE

AVE

4TH ST

JR AVE

GARY

JENNA AVE

BARNES AVE

MANDY AVE

PAMELA AVE

SUE ELLEN AVE

3RD TER

ROSS AVE

KREBBS D

3RD ST

JENNA CT

Barr Footer: ArcGISPro 3.1.3, 2024-01-31 09:12 File: I:\Projects\25\49\1019\Maps\Reports\Federal_Groundwater_Tech_Memo_2023\2023 AMR Report Figures\2023 AMR Report Figures.aprx Layout: Figure 4 March 2023 Groundwater Contours User: MRQ

MW-08 752.53

752

MW-01 751.37

MW-06 751.27 751

MW-02 750.09

750

POWELL RD

749

748

MW-03 746.60

MW-07 734.89* 747

MW-04 746.92

749

MW-05 749.83

POWELL RD

TRUMAN RD

Note: Property boundary obtained from Jackson County parcel dataset, MO GIS Department. Imagery: Nearmap, September 2021

Property Boundary

Groundwater Contours

Downgradient Monitoring Well

Groundwater Flow Direction

Upgradient Monitoring Well

* MW-7 not contoured

175

350 Feet

525

GROUNDWATER CONTOURS MARCH 2023 Independence Power & Light Independence, Missouri FIGURE 4

BOBBY AVE

VALEEN AVE

AVE

4TH ST

JR AVE

GARY

JENNA AVE

BARNES AVE

MANDY AVE

PAMELA AVE

SUE ELLEN AVE

3RD TER

ROSS AVE

KREBBS D

3RD ST

JENNA CT

Barr Footer: ArcGISPro 3.1.3, 2024-01-31 09:26 File: I:\Projects\25\49\1019\Maps\Reports\Federal_Groundwater_Tech_Memo_2023\2023 AMR Report Figures\2023 AMR Report Figures.aprx Layout: Figure 5 June 2023 Groundwater Contours User: MRQ

MW-08 751.47

MW-01 749.62

MW-06 753.65 3

MW-02 749.69

MW-03 745.17 747

74 8

POWELL RD

0 75

746

MW-07 737.75*

MW-04 746

74 8

MW-05 748.57

POWELL RD

TRUMAN RD

Note: Property boundary obtained from Jackson County parcel dataset, MO GIS Department. Imagery: Nearmap, September 2021

Property Boundary

Groundwater Contours

Downgradient Monitoring Well

Groundwater Flow Direction

Upgradient Monitoring Well

* MW-07 not contoured

175

350 Feet

525

GROUNDWATER CONTOURS JUNE 2023 Independence Power & Light Independence, Missouri FIGURE 5

Barr Footer: ArcGISPro 3.1.3, 2024-01-30 13:49 File: I:\Projects\25\49\1019\Maps\Reports\Federal_Groundwater_Tech_Memo_2023\2023 AMR Report Figures\2023 AMR Report Figures.aprx Layout: Figure 6 March 2023 Groundwater Concentrations Map User: MRQ

Dissolved Lithium Total Arsenic

40 ug/l 10 ug/l

Total Lithium

40 ug/l

MW-8 Dissolved Lithium Total Lithium

MW-6 Dissolved Lithium Total Lithium

3/02/2023 98.2 ug/l 106 ug/l

3/02/2023 46.8 ug/l 48.5 ug/l

MW-1*

MW-2*

MW-7 Dissolved Lithium Total Lithium

LITTLE BLUE PKWY

Parameter

EPA 40 CFR EPA Maximum 257.95(h)(2) Contaminant Assessment Levels Monitoring

3/02/2023 111 ug/l 141 ug/l

MW-3 Total Arsenic

MW-4 Total Arsenic

3/02/2023 26.8 ug/l

3/02/2023 35.3 ug/l

MW-5*

Note: Property boundary obtained from Jackson County parcel dataset, MO GIS Department. Imagery: Nearmap, September 2021

Property Boundary Downgradient Monitoring Well Upgradient Monitoring Well

Notes: * No exceedances

175

350 Feet

525

MARCH 2023 GROUNDWATER CONCENTRATIONS Independence Power & Light Independence, Missouri FIGURE 6

Barr Footer: ArcGISPro 3.1.3, 2024-01-30 13:49 File: I:\Projects\25\49\1019\Maps\Reports\Federal_Groundwater_Tech_Memo_2023\2023 AMR Report Figures\2023 AMR Report Figures.aprx Layout: Figure 7 June 2023 Groundwater Concentrations Map User: MRQ

Dissolved Lithium

40 ug/l

Total Arsenic

10 ug/l

Total Lead

15 TT(12) ug/l

15 ug/l

Total Lithium

40 ug/l

MW-8 Dissolved Lithium Total Lithium

MW-6 Dissolved Lithium Total Lead Total Lithium

6/13/2023 93.0 ug/l 100 ug/l

MW-1 Total Arsenic

6/13/2023 50.0 ug/l 16.3 ug/l 52.4 ug/l

6/13/2023 10.2 ug/l

MW-2*

MW-3 Total Arsenic

KWY

6/13/2023 44.4ug/l 42.9 ug/l

LITTLE

MW-7 Dissolved Lithium Total Lithium

6/13/2023 40.9 ug/l

BLUE P

Parameter

EPA 40 CFR EPA Maximum 257.95(h)(2) Contaminant Assessment Levels Monitoring

MW-4 Total Arsenic

6/13/2023 36.3 ug/l

MW-5*

Note: Property boundary obtained from Jackson County parcel dataset, MO GIS Department. Imagery: Nearmap, September 2021

Property Boundary Downgradient Monitoring Well Upgradient Monitoring Well

Notes: * No exceedances

175

350 Feet

525

JUNE 2023 GROUNDWATER CONCENTRATIONS Independence Power & Light Independence, Missouri FIGURE 7

Attachment B Tables

TABLE 1 MONITORING WELL CONSTRUCTION SUMMARY Well ID

Installation Date

Well Type

Surface

Riser

Elevation

(Feet)

Riser

Borehole

Riser Pipe

Height

Diameter

(Inches)

MW-1

6/26/2019

Permanent

756.09

758.54

2.45

8.25

MW-2

6/25/2019

Permanent

752.94

755.45

2.51

8.25

MW-3

6/25/2019

Permanent

749.09

751.63

2.54

8.25

MW-4

6/25/2019

Permanent

749.49

751.17

1.68

8.25

MW-5

8/5/2019

Permanent

756.63

758.81

2.18

MW-6

8/2/2019

Permanent

774.29

776.01

1.72

MW-7

8/4/2019

Permanent

776.5

778.29

1.79

MW-8

8/2/2019

Permanent

770.69

772.61

1.92

Notes: (1) Elevations were surveyed on 5/5/2020.

Riser Pipe

Screened Interval (Feet) 1

Material Schedule 40 PVC Schedule 40 PVC Schedule 40 PVC Schedule 40 PVC Schedule 40 PVC Schedule 40 PVC Schedule 40 PVC Schedule 40 PVC

Top

Bottom

741.09

721.09

737.94

717.94

734.09

714.09

737.49

707.49

710.63

700.63

708.29

703.29

696.5

686.5

138.53

128.53

Table 2 Groundwater Elevation Summary

March 2023

Location

MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-7 MW-8

June 2023

Water Level Water Level Top of Riser Depth to Elevation (ft - Depth to Elevation (ft (ft-MSL) Water (ft) MSL) Water (ft) MSL)

758.54 755.45 751.63 751.17 758.81 776.01 778.29 772.61

7.17 5.36 5.03 4.25 8.98 24.74 16.16 20.08

751.37 750.09 746.60 746.92 749.83 751.27 734.89 752.53

8.92 5.76 6.46 5.17 10.24 22.36 21.51 21.14

749.62 749.69 745.17 746.00 748.57 753.65 737.75 751.47

Table 3 2023 Groundwater Analytical Summary

Location

MW-1

MW-2

MW-3

MW-4

MW-5

MW-6

MW-7

MW-8

6/13/2023

3/02/2023

6/13/2023

3/02/2023

6/13/2023

3/02/2023

6/13/2023

3/02/2023

6/13/2023

3/02/2023

6/13/2023

3/02/2023

6/13/2023

3/02/2023

6/13/2023

1800 12600 63800 < 200 U 500000 < 100 U < 100 U < 100 U 840000 342000

1700 17700 72900 < 200 U 437000 < 100 U < 100 U < 100 U 718000 186000

1000 < 10000 U 42600 200 649000 < 100 U < 100 U < 100 U 857000 301000

< 1000 U 17000 59200 < 200 U 621000 < 100 U < 100 U < 100 U 856000 303000

1600 1600 1600 < 10000 U 16300 < 10000 U 19200 20000 20000 320 < 200 U < 200 U 489000 536000 530000 < 100 U < 100 J- < 100 UJ< 100 U < 100 J- < 100 UJ< 100 U < 100 J- < 100 UJ680000 771000 763000 11900 52300 63500

6100 15900 2500 300 277000 < 100 U < 100 U < 100 U 507000 5500

5500 21100 2500 < 200 U 266000 < 100 U < 100 U < 100 U 470000 1100

5400 37400 77900 230 236000 < 100 U < 100 U < 100 U 943000 75500

4100 148000 101000 < 200 U 239000 < 100 U < 100 U < 100 U 1000000 89200

10400 78300 29100 440 72100 < 100 U < 100 U < 100 U 525000 16800

2300 3800 3400 < 10000 U < 10000 U < 10000 U 30000 133000 167000 740 < 200 U < 2000 U 76900 388000 294000 < 100 UJ< 100 U < 100 U < 100 U < 100 U < 100 U < 100 UJ< 100 U < 100 U 656000 752000 868000 17900 5300 12200

< 75.0 U < 1.0 U < 1.0 U 112 < 1.0 U 2770 < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 33.2 18600 6960 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 60600 < 1.0 U < 50.0 U < 75.0 U < 1.0 U 4.3 132 < 1.0 U 2980 < 0.50 U 168000 < 5.0 U < 10 U < 5.0 U < 10.0 U 2130 < 10.0 U 33.1 19800 7570 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 64200 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U < 1.0 U 121 < 1.0 U 2060 < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 14.3 18000 6340 < 0.20 UJ< 20.0 U < 5.0 U < 15.0 U < 7.0 U 44400 < 1.0 U < 50.0 U < 75.0 U < 1.0 U 10.2 168 < 1.0 U 2160 < 0.50 U 144000 < 5.0 U < 10 U < 5.0 U < 10.0 U 7300 < 10.0 U 14.1 18900 7260 < 0.20 UJ< 20.0 U < 5.0 U < 15.0 U < 7.0 U 47000 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U < 1.0 U 345 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 21.7 34400 4680 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 11500 < 1.0 U < 50.0 U < 75.0 U < 1.0 U 1.2 732 < 1.0 U < 100 U < 0.50 U 200000 < 5.0 U < 10 U < 5.0 U < 10.0 U 18300 < 10.0 U 19.8 36400 5160 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 11900 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U < 1.0 U 163 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U 210 < 10.0 U 19.2 34200 4390 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 10900 < 1.0 U < 50.0 U 303 < 1.0 U < 1.0 U 906 < 1.0 U < 100 U < 0.50 U 190000 < 5.0 U < 10 U < 5.0 U < 10.0 U 16900 < 10.0 U 19.6 35500 4810 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 11400 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U 3.7 490 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 10.8 35500 2260 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 72200 < 1.0 U < 50.0 U 79.3 < 1.0 U 26.8 639 < 1.0 U < 100 U < 0.50 U 140000 < 5.0 U < 10 U < 5.0 U < 10.0 U 10400 < 10.0 U 10.2 33800 2250 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 69500 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U 3.7 259 < 1.0 U 125 < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 16.5 17100 1120 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 66900 < 1.0 U < 50.0 U 98.9 < 1.0 U 35.3 487 < 1.0 U 133 < 0.50 U 81200 < 5.0 U < 10 U < 5.0 U < 10.0 U 19600 < 10.0 U 17.4 17900 1310 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 70500 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U 2.8 256 < 1.0 U 120 < 0.50 U < 5.0 U < 10 UJ< 5.0 U < 10.0 U < 50.0 U < 10.0 U 18.8 16600 918 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 64600 < 1.0 U < 50.0 U 153 < 1.0 U 36.3 564 < 1.0 U 121 < 0.50 U 77700 < 5.0 U < 10 UJ< 5.0 U < 10.0 U 23200 < 10.0 U 17.9 17400 1140 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 68100 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U < 1.0 U 473 < 1.0 U 948 < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 46.8 16000 342 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 260000 < 1.0 U < 50.0 U < 75.0 U < 1.0 U 2.1 560 < 1.0 U 998 < 0.50 U 66900 < 5.0 U < 10 U < 5.0 U < 10.0 U 3450 < 10.0 U 48.5 16600 375 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 268000 < 1.0 U < 50.0 U

< 75.0 U < 2.4 UB 1.8 442 < 1.0 U 959 < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U 383 < 10.0 U 50.0 16100 340 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 257000 < 1.0 U < 50.0 U 996 5.0 2.6 544 < 1.0 U 985 < 0.50 U 67700 < 5.0 U < 10 U < 5.0 U < 10.0 U 7990 16.3 52.4 17000 457 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 277000 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U 1.4 21.6 < 1.0 U 1190 < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 111 2550 < 5.0 U < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 187000 < 1.0 U < 50.0 U < 75.0 U 1.2 1.4 85.1 < 1.0 U 1250 < 0.50 U 24400 < 5.0 U < 10 U < 5.0 U < 10.0 U 117 < 10.0 U 141 2690 26.2 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 193000 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U 1.2 86.4 < 1.0 U 1420 < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 44.4 4370 8.3 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 205000 < 1.0 U < 50.0 U < 75.0 U < 1.0 U 1.2 114 < 1.0 U 1440 < 0.50 U 23300 < 5.0 U < 10 U < 5.0 U < 10.0 U 205 < 10.0 U 42.9 4540 89.7 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 220000 < 1.0 U < 50.0 U

MW-1

Date 3/02/2023 Sample Type

Parameter Last Updated Exceedance Key General Parameters Carbon, total organic Chemical Oxygen Demand Chloride Fluoride Hardness, as CaCO3 Nitrogen, nitrate + nitrite, as N Nitrogen, nitrate, as N Nitrogen, nitrite, as N Solids, total dissolved Sulfate, as SO4 Metals Aluminum Antimony Arsenic Barium Beryllium Boron Cadmium Chromium Chromium, hexavalent Cobalt Copper Iron Lead Lithium Magnesium Manganese Mercury Molybdenum Nickel Selenium Silver Sodium Thallium Zinc Aluminum Antimony Arsenic Barium Beryllium Boron Cadmium Calcium Chromium Chromium, hexavalent Cobalt Copper Iron Lead Lithium Magnesium Manganese Mercury Molybdenum Nickel Selenium Silver Sodium Thallium Zinc

Total or Dissolved Units

NA NA NA NA NA NA NA NA NA NA

ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l

Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total Total

ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l

EPA Maximum Contaminant Levels 03/01/2018 Bold

10000 10000 1000

6 10 2000 4 5 100 100 (14) 6 1300 TT(12) 15 40

2 100 50

6 10 2000 4 5 100 100 (14) 6 1300 TT(12) 15 TT(12)

15 40

2 100 50

40 CFR 257.95(h)(2) Groundwater Protection Standards 04/01/2012 Underline

4000

15 TT(12)

< 75.0 U < 1.0 U 3.2 443 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 10.1 36600 2490 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 81500 < 1.0 U < 50.0 U 152 < 1.0 U 40.9 682 < 1.0 U < 100 U < 0.50 U 153000 < 5.0 U < 10 U < 5.0 U < 10.0 U 14100 < 10.0 U 10.1 37200 2820 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 90900 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U 3.2 442 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 10.3 36900 2420 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 84300 < 1.0 U < 50.0 U 121 < 1.0 U 39.5 677 < 1.0 U < 100 U < 0.50 U 151000 < 5.0 U < 10 U < 5.0 U < 10.0 U 14100 < 10.0 U < 10.0 U 36800 2670 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 88500 < 1.0 U < 50.0 U

1400 1700 1300 < 10000 UJ- < 10000 U < 10000 U 47600 47300 72700 280 310 < 200 U 259000 262000 293000 < 100 U < 100 U < 100 U < 100 U < 100 U < 100 U < 100 U < 100 U < 100 U 402000 396000 431000 2100 1400 1200 < 75.0 U < 1.0 U < 1.0 U 202 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U < 10.0 U 17500 87.7 J < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 43600 < 1.0 U < 50.0 U 190 < 1.0 U < 1.0 U 219 < 1.0 U < 100 U < 0.50 U 75900 < 5.0 U < 10 U < 5.0 U < 10.0 U 603 < 10.0 U < 10.0 U 16800 1010 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 41900 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U < 1.0 U 217 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U < 10.0 U 17700 1090 J < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 44100 < 1.0 U < 50.0 U 179 < 1.0 U < 1.0 U 226 < 1.0 U < 100 U < 0.50 U 76900 < 5.0 U < 10 U < 5.0 U < 10.0 U 667 < 10.0 U < 10.0 U 16900 1130 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 42700 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U < 1.0 U 224 < 1.0 U < 100 U < 0.50 U < 5.0 U < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U < 10.0 U 17900 1050 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 42000 < 1.0 U < 50.0 U 1090 < 1.0 U 1.2 278 < 1.0 U < 100 U < 0.50 U 85500 < 5.0 U < 10 U < 5.0 U < 10.0 U 1990 < 10.0 U < 10.0 U 19300 1570 < 0.20 U < 20.0 U < 5.0 U < 15.0 U < 7.0 U 45500 < 1.0 U < 50.0 U

< 75.0 U < 1.0 U 1.9 167 < 1.0 U 646 < 0.50 U 5.5 < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 98.2 < 50.0 U < 5.0 U < 0.20 U < 20.0 U 11.9 < 15.0 U < 7.0 U 181000 < 1.0 U < 50.0 U 344 < 1.0 U 2.1 243 < 1.0 U 701 < 0.50 U 155000 6.4 < 10 U < 5.0 U < 10.0 U 353 < 10.0 U 106 179 5.3 < 0.20 U < 20.0 U 13.9 < 15.0 U < 7.0 U 191000 < 1.0 U < 50.0 U

114 < 1.0 U 1.9 190 < 1.0 U 609 < 0.50 U 6.3 < 10 U < 5.0 U < 10.0 U < 50.0 U < 10.0 U 93.0 < 50.0 U < 5.0 U < 0.20 U < 20.0 U 11.3 < 15.0 U < 7.0 U 166000 < 1.0 U < 50.0 U 156 1.0 1.9 215 < 1.0 U 635 < 0.50 U 118000 7.4 < 10 U < 5.0 U < 10.0 U 84.3 < 10.0 U 100 57.9 < 5.0 U < 0.20 U < 20.0 U 12.3 < 15.0 U < 7.0 U 182000 < 1.0 U < 50.0 U

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Data Footnotes and Qualifiers Barr Standard Footnotes and Qualifiers N

Sample Type: Normal

Sample Type: Field Duplicate

Recommended sample preservation, extraction or analysis holding time was exceeded. Estimated detected value. Either certain QC criteria were not met or the concentration is between the laboratory's detection and quantitation limits. The result is an estimated quantity and may be biased high.

J J+ J-

The result is an estimated quantity and may be biased low.

The analyte was analyzed for, but was not detected. The analyte was analyzed for, but was not detected. The recommended sample preservation, extraction or analysis holding time was exceeded.

UH UJ

The analyte was analzyed for, but was not detected. The reported value is approximate and may be inaccurate or imprecise.

(19)

At no time can turbidity go above 5 NTU.

(14)

Based on the criteria for chromium, total.

TT(12)

Treatment technique; Copper action level 1.3 mg/l; lead action level 0.015 mg/l.

EPA Maximum Contaminant Levels

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Attachment C Hydrographs

MW-1 GROUNDWATER ELEVATION HYDROGRAPH 752

Groundwater Elevation (ft-msl)

751

750

749

748

747

746

745

Date

MW-2 GROUNDWATER ELEVATION HYDROGRAPH 750

750

Groundwater Elevation (ft-msl)

750

749

748

Date

MW-3 GROUNDWATER ELEVATION HYDROGRAPH 747

747

Groundwater Elevation (ft-msl)

746

745

744

743

Date

MW-4 GROUNDWATER ELEVATION HYDROGRAPH 748

748

Groundwater Elevation (ft-msl)

747

746

745

744

Date

MW-5 GROUNDWATER ELEVATION HYDROGRAPH 752

751

Groundwater Elevation (ft-msl)

750

749

748

747

746

745

744

Date

MW-6 GROUNDWATER ELEVATION HYDROGRAPH 755

Groundwater Elevation (ft-msl)

754

753

752

751

750

749

Date

MW-7 GROUNDWATER ELEVATION HYDROGRAPH 765

Groundwater Elevation (ft-msl)

760

755

750

745

740

735

730

Date

MW-8 GROUNDWATER ELEVATION HYDROGRAPH 764

762

Groundwater Elevation (ft-msl)

760

758

756

754

752

750

748

Date

Attachment D Field Data