B08_Attachment_8_Hydrogeologic_Assessment.pdf

107854-001

400 North 34th Street Suite 100 PO Box 300303 Seattle, Washington 98103-8636 206 632-8020 Fax 206 695-6777 www.shannonwilson.com

January 5, 2022

Mr. Darren Stewart, P.E.

SEH, Inc.

934 Main Ave, Unit C Durango, CO 81301

RE: DRAFT HYDROGEOLOGIC ASSESSMENT, NATIONAL PARK SERVICE WATER

SUPPLY WELL, ORGAN PIPE CACTUS NATIONAL MONUMENT, ARIZONA

Dear Mr. Stewart, Shannon & Wilson prepared this letter and participated in this project as a subconsultant to Short Elliott Hendrickson, Inc. (SEH). Our scope of services was specified in our Subcontract Agreement for Professional Services with SEH, dated August 6, 2021, SEH Contract No. 140P2019D0015. This Agreement is in support of water supply improvements at Organ Pipe Cactus National Monument (OPCNM) as specified by National Park Service (NPS) Contract No. 140P2019D0015. This letter presents our design and hydrogeologic assessment of a 48-hour pumping test and was prepared by the undersigned.

We appreciate the opportunity to be of service to you on this project. If you have questions concerning this letter, or we may be of further service, please contact us.

BACKGROUND

The NPS is the process of improving its aging water system, including supply, storage, and distribution components for visitor and staff facilities at and around the Kris Eggle Visitor Center and Twin Peaks Campground. In 2019, a new water supply well, the replacement North Well (Well 6), was installed to provide water to the park water system. The NPS plans to install a second new well to replace the existing failing Old South Well (Well 4) and secure a stable and reliable water supply for the future use of OPCNM.

We understand that the pumping test conducted in 2019 after construction of Well 6 to determine its well capacity was not adequate to provide insight into proper spacing for an additional well. We were requested to run a longer pumping test to determine the cone of influence of Well 6 and gain further understand of the hydraulic properties of the aquifer.

http://www.shannonwilson.com/

107854-001 Letter DRAFT JSB comments (002).docx 107854-001

We conducted a 48-hour constant rate pumping test on Well 6 and monitored water levels at two other wells to inform recommendations for the location and design of the new well.

Site Description

The Site is in the south part of OPCNM, in Pima County, Arizona. The Site is approximately five miles north of the town of Lukeville, about 22 miles south of the town of Why, and 200 yards west of State Route 85. The Site is accessible by a short dirt road spur from a park road, Twin Peaks Road, and is adjacent to an ephemeral stream in a dry wash, running North-South, just west of the Site.

The Site consists of three wells: Old South Well (Well 4), Old North Well (Well 5) and the replacement North Well (Well 6). The Well 6 location is approximately latitude 31.95032 North, longitude 112.8015 West, as shown in Figure 1. The other two wells, used as observation wells during the test, are approximately 83 feet to the southeast (Well 5) and 263 feet to the south (Well 4) from Well 6, the pumping well.

WELL ASSESSMENT AND PUMPING TEST

Shannon & Wilson completed our well assessment and pumping test between August 26, 2021 and November 19, 2021. The well assessment and test process consisted of:

1. Reviewing existing boring logs, construction records, and other well data;

2. Performing a site reconnaissance visit;

3. Coordinating with NPS to perform a constant rate pumping test;

4. Monitoring water levels and pumping rate during the pumping test; and

5. Analyzing the pumping test data.

Well Assessment and Site Reconnaissance

We visited the Site on August 26, 2021 along with representatives of NPS and SEH. We examined Wells 4, 5, and 6 and received reports including boring logs and construction logs for Well 6, and more limited information for Wells 4 and 5. We received further information from personal communications with NPS staff.

Well 6

The pumping well used for our test, Well 6, was drilled and installed in September 2019 to replace the failing Well 5. Well 6 is currently the primary active supply well for the OPCNM. The well was drilled using the mud rotary method and completed to a depth of 550 feet below ground surface (bgs). The upper 20 feet was drilled as an 18.5-inch diameter borehole. The borehole was then reduced to a 13.75-inch diameter for the remaining 530 feet of drilling.

According to the boring log, the upper 20 feet of the borehole comprised of sedimentary conglomerate. The remainder of the borehole was drilled through volcanic rocks of various composition, with broken volcanic rock encountered between 320 and 530 feet bgs. We assume the broken volcanic rock to be the water-bearing unit that comprises the aquifer.

Water was encountered during drilling at 340 feet. To a depth of 20 feet bgs, a 10-inch diameter outer steel casing was installed. To a depth of 330 feet bgs and from 530 to 550 feet bgs, an 8-inch diameter steel casing was installed. An 8-inch diameter 100-slot (0.100-inch perforation width) wire wrap screen was installed from 330 to 530 feet bgs.

A 0.25-inch gravel pack was installed in the annular space between the borehole wall and the steel casing or wire wrap screen from 300 to 550 feet bgs. A bentonite seal was installed between the borehole wall and the steel casing from 20 to 300 feet bgs, and a concrete surface seal installed between the outer and inner casing from the ground surface to 20 feet bgs. After well construction, the reported static water level was 346 feet bgs.

In October 2019, a 15-horsepower submersible electric pump was installed at 473 feet bgs and a pumping test was conducted. Prior to the test, the static water level was reported as 346 feet bgs. The well was pumped at 50 gallons per minute (gpm) for 11 hours and 5 minutes, with the water level during pumping stabilizing at a reported 347.5 feet bgs (1.5 inches of drawdown). No further water level measurements were recorded during recovery.

A copy of the Well Driller Report and Well Log, as well as the Well Test Report, referenced in this section are included in Appendix A.

Well 5

Well 5, used as an observation well for our pumping test, is currently used as a monitoring well by NPS. We understand the well has a total depth of 410 feet bgs. The entirety of the well has a 12-inch steel casing installed aside from two 10-foot screen sections: from 350 to 360 feet bgs and from 400 to 410 feet bgs.

A pumping test was conducted at Well 5 in August 1974. Prior to the test, the static water level was reported as 310.71 feet bgs. The well was pumped at approximately 114 gpm for 935 minutes, with a total reported drawdown of 6.78 feet. After 740 minutes of recovery, the water level had recovered to the pre-test static water level.

A copy of the Well Test Report referenced in this section is included in Appendix A.

Well 4

Well 4, used as an observation well for our pumping test, is currently used as a back-up water supply well by NPS. We understand that although currently active, the well is failing due to degradation of the casing and iron deposition. The borehole was drilled to a depth of 430 feet in November 1957. During drilling, water was encountered at 330 feet bgs, and was reported to have risen 20 feet in the boring during drilling.

A 12-inch diameter steel casing was installed to a depth of 428 feet bgs, with the bottom left open. The casing was installed with a section of ½-inch wide torch-cut perforations from 365 to 425 feet bgs. After well installation, the static water level was reported as 310 feet bgs.

During the 1974 Well 5 pumping test, water levels at Well 4 were monitored. No static water level was reported prior to the test, however after 125 minutes of pumping, the water level was reported as 307.60 feet bgs. After 929 minutes of pumping, the water level was reported as 307.78, a drawdown of 0.18 feet since the first water level measurement.

A copy of the Well Schedule and Driller Log, as well as the Well Test Report referenced in this section is included in Appendix A.

Pumping Test

Shannon & Wilson coordinated with NPS staff to conduct a 48-hour constant rate pumping test in November 2021. On November 14, NPS staff shut off the pump at Well 6 to allow water levels to return to static prior to the pumping test.

We arrived at the Site on November 15 and met NPS Regional Hydrologist, Salek Shafiqullah. Well 6 had a locked steel cover over the casing stick-up and was inaccessible until the following day when NPS staff opened it. The water level at Well 5 was measured with a manual water level indicator as 353.96 feet bgs. The water level at Well 4 was measured with a manual water level indicator as 352.65 feet bgs.

On November 16, NPS staff installed 1.5-inch fire hose from the well system connection point at the Well 5 wellhouse and ran the hose to the ground surface at the dry wash nearby.

We installed pressure dataloggers at Well 5 and Well 6, as well as a barometric pressure datalogger inside the Well 5 wellhouse. At Well 4, the sounding tube was too narrow to fit the pressure datalogger, so we attempted to install the datalogger into the well casing outside of the sounding tube. The datalogger became stuck in the pump wiring above the static water depth, at about 100 feet bgs, so as a result no datalogger data is available for Well 4. Pumping test and recovery water levels at Well 4 used for analysis are manual measurements that have been manually adjusted to compensate for barometric pressure.

Pumping test and recovery water levels at Wells 5 and 6 are derived from the pressure datalogger data and barometric compensation.

The static water level prior to the test at Well 4 was measured as 352.75 feet bgs. The static water level prior to the test at Well 5 was measured as 353.83 feet bgs. The static water level prior to the test at Well 6 was measured as 353.68 feet bgs.

On November 16, at 9:29:45, the Well 6 pump was turned on at full capacity, at which point the 48-hour constant rate pumping test began. Discharge water was routed to the dry wash and the flow rate was measured periodically by observing the NPS flow meter totalizer over one-minute intervals. The flow rate remained constant throughout the duration of the test and the average flow rate was approximately 55 gpm. The pump was shut off at 9:29:45 on November 18, after 2880 minutes of pumping, at which point the pumping test concluded and the recovery period began.

Water levels at each of the three wells were stable by the end of the pumping test. The drawdown at Well 6 after the 48 hours of pumping was 1.23 feet, resulting in a specific capacity of 44.7 gpm per foot of drawdown. The drawdown at Well 5 was 0.57 feet. The drawdown at Well 4 was 0.38 feet.

We continued to observe water levels at the wells for over 24 hours of recovery time. The water level at Well 6 recovered to within 0.07 feet of the static water level prior to the test.

The water level at Well 5 recovered to within 0.02 feet of the static water level prior to the test. The water level at Well 4 recovered to within 0.05 feet of the static water level prior to the test.

The observed drawdown and recovery for Wells 4, 5, and 6 are shown in Figures 2 through

4. Figure 5 shows the radial distance of each well to the pumping well plotted against the total drawdown.

Pumping Test Analysis

Based on our observations of the water levels at the pumping well and two observation wells during the pumping test, the aquifer can produce at least 55 gpm over a sustained period of time. All three wells stabilized with little drawdown after less than 48 hours of pumping. All three wells recovered to their respective pre-test static water levels within the 24 hours of observed recovery time.

We analyzed the pumping test data using the Theis (1935) and Cooper-Jacob (1946) solutions, assuming a confined aquifer. These methods assume the discharge from the pumping well comes only from the storage of the confined aquifer in which the screened portion of the pumping well is located. Our analysis also assumes the bottom of the aquifer at 530 feet bgs, along the unit boundary observed at the time of Well 6 drilling, and the top of the aquifer at the static water level we observed at Well 6 prior to the pumping test,

353.68 feet bgs. As a result, the assumed aquifer thickness is 176.32 feet. We analyzed the pumping test data using the solutions of drawdown and recovery data plotted against elapsed time and against radial distance from the pumping well. Based on our analysis of the pumping test data, we have estimated values for the following interpreted aquifer parameters:

Transmissivity (T) of the pumped aquifer ranges from 8205.4 to 11,830 ft2 /day based on Theis drawdown and recovery solutions; T ranges from 7347.3 to 13,650 ft2/day based on Cooper-Jacob solutions.

Storativity (S) of the pumped aquifer ranges from 0.00603 to 0.05391 based on Theis solutions; S ranges from 0.001433 to 0.03887 based on Cooper-Jacob solutions.

Analysis of the radial distance-drawdown data indicates a T value for the aquifer of 13,386 ft2/day and S value of 0.0015.

See Table 1 for complete pumping test results and interpreted aquifer parameters.

RECOMMENDATIONS AND CONCLUSIONS

Based on our assessment of the well data, and analysis of the pumping test data, Shannon & Wilson believes that the aquifer is suitable for construction and operation of an additional water supply well.

We understand that NPS does not plan to pump both the existing Well 6 supply well and the new supply well at the same time, so there is not likely to be a significant risk of interference between the wells’ zone of influence. Even if concurrent pumping was necessary, Well 4 experienced only minimal drawdown and subsequent rapid recovery from the pumping at Well 6. We believe installing and operating the new well in the vicinity of Well 4, with a pump intake of similar depth to that of Well 6 would produce similar pumping and discharge results as observed at Well 6. This location and intake depth would allow for sustained pumping at a rate sufficient for our understanding of OPCNM’s requirements. Assuming the same static water level and intake depth, there will be an available drawdown of greater than 100 feet, adequate for water supply in the long-term, even if there is a continued long-term decline in the water level of the aquifer. Figure 6 shows the recommended approximate location for the new replacement well.

Due to the lack of information of any potential aquifer boundaries or low permeability zones to the south of Well 4, we do not recommend constructing the new well significantly south of Well 4, unless further testing or exploration occurs.

We recommend that instead of using one well as the primary supply well and only using the other well as a contingency in case of issues with the primary well, each well is used relatively evenly in an alternating fashion.

LIMITATIONS

We have prepared the document "Important Information About Your Geotechnical/ Environmental Report" to assist you and others in understanding the use and limitations of this report. Please read this document to learn how you can lower your risks for this project.

This report was prepared for the exclusive use of SEH, the NPS, and their representatives for use in the design of water supply well at the Site. This report should be provided to prospective contractors for information of factual data only, and not as a warranty of subsurface conditions, such as those interpreted from the exploration log and discussions of subsurface conditions included in this report.

The analyses, conclusions, and recommendations contained in this report are based on Site conditions as they presently exist. We assume that the results of the exploration made for this project represent the subsurface conditions throughout the Site, i.e., the subsurface conditions everywhere are not significantly different from those disclosed by the explorations.

Within the limitations of the scope, schedule, and budget, the analyses, conclusions, and recommendations presented in this report were prepared in accordance with generally accepted professional hydrogeologic principles and practice in this area at the time this report was prepared. We make no other warranty, either express or implied.

Unanticipated subsurface conditions are commonly encountered and cannot be fully determined by merely taking soil or rock samples or completing subsurface explorations.

Such unexpected conditions frequently require that additional expenditures be made to attain a properly constructed project. There, some contingency fund is recommended to accommodate such potential extra costs.

The scope of our services for this report did not include any assessments or evaluations regarding the presence or absence of wetlands, cultural resources, or hazardous or toxic substances on or below the Site. If a service is not specifically indicated in this report, do not assume that it was performed.

REFERENCES

Cooper, H. H. and Jacob, C. E., 1946, A generalized graphical method for evaluating formation constants and summarizing well field history: American Geophysical Union Transactions, v. 27, p. 526-534.

Theis, C. V., 1935, The relation between the lowering of the piezometric surface and the rate and duration of discharge of a well using ground-water storage: Transactions of the American Geophysical Union, v. 16, p. 519-524.

Sincerely, SHANNON & WILSON

Nathan Cutler Jim Bailey, LHG Geology Staff Well Services Director

NAC:JSB/xxx:xxx

Enc. Table 1 – Summary of Pumping Test Results and Interpreted Aquifer Parameters Figure 1 – Wells Location Map Figure 2 – Well 6 Hydrograph Figure 3 – Well 5 Hydrograph Figure 4 – Well 4 Hydrograph Figure 5 – Distance-Drawdown Plot Figure 6 – New Well Recommended Location Map Appendix A – Well Drilling Logs, Construction Reports, Drawings, and Historical

Pumping Test Data Important Information About Your Geotechnical/Environmental Report c: National Park Service

Draft Hydrogeologic Assessment Organ Pipe Cactus National Monument, Arizona

Well No. Well Location

Well Designatio n During

Test

Radial Distance to Pumping

Well

Approx.

Grade

Elevation2

Static Groundwat er Level Depth

Approx.

Static

Groundwat er Level

Elevation

Screen(s)/P erforated

Casing Top Depth

Screen(s)/P erforated Casing Bottom Depth

Screen(s)/P erforated Casing Length

Screen(s)/P erforated

Casing Top Elevation

Screen(s)/P erforated Casing Bottom

Elevation Test Dates Pumping Duration

Approx.

Pumping

Rate

Drawdown at End of Pumping

Specific Capacity

Aquifer Model

Transmissivit y (Drawdown)

Transmissiv ity

(Recovery) Storativity

(Drawdown) Transmissiv ity Storativity

Transmissivit y (Distance-drawdown)

Storativity (Distance-drawdown)

(lat. dd, long.

dd) (feet) (feet

NAVD88) (feet bgs) (feet NAVD88) (feet bgs) (feet bgs) (feet) (feet

NAVD88)

(feet

NAVD88) (mm/dd/yy) (minutes) (gpm) (feet) gpm/ft (feet2/day) (feet2/day) (feet2/day) (feet2/day)

Well 4 31.949603, -112.8016193 Observation

Well 263.44 1661 352.75 1308.25 365 425 60 1296 1236 11/16/21- 11/19/21 2880 55 0.385 - Confined 9059.5 8205.4 0.00603 7347.3 0.002909 - -

Well 5 31.950481, -112.8016893 Observation

Well 82.87 1665 353.83 1311.17 350

11/16/21- 11/19/21 2880 55 0.57 - Confined 8857.2 8930.7 0.05179 10,010 0.03887 - -

Well 6 31.95032, -112.80154

Pumping Well 0.33 1664 353.68 1310.32 330 530 200 1334 1134 11/16/21-

11/19/21 2880 55 1.236 44.7 Confined 9404 11,830 0.05391 13,650 0.001433 - -

Combined (All) - - - - - - - - - - - 11/16/21-

11/19/21 2880 55 - - Confined - - - 10,790 0.007996 13,386 0.0015

NOTES:

lat. dd = latitude decimal degrees; long. dd = longitude decimal degrees; NAVD88 = North American Vertical Datum of 1988; bgs = below ground surface; gpm = gallons per minute

1. Well 4 has one section of torch-cut perforated steel casing; Well 5 has two sections of screen; Well 6 has one section of 100-slot wire wrap screen

2. Approximate grade elevations from Google Earth

3. Location estimated from Google Earth

4. Location from 'Well 6 Final As-Built' Drawings, Site Plan C1

5. Drawdown at end of pumping value for Well 4 is closest available data to end of pumping, at elapsed time = 2810 minutes

6. Drawdown is average of values over last 10 minutes of pumping

Table 1 - Summary of Pumping Test Results and Interpreted Aquifer Parameters

Approximate Well Construction Details1 Pumping Test Results Theis Solution

Interpreted Aquifer Parameters

General Well Information Cooper-Jacob Solution

107854-001 Page 1 of 1 Table_1.xlsx - 1/5/2022

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FIG. 1

WELLS LOCATION MAP

Hydrogeologic Assessment Organ Pipe Cactus National Monument, Arizona

January 2022

0 80 160

Scale in Feet

Well 4 Boring Designation and Approximate Location

LEGEND

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29.0

29.5

30.0

30.5

31.0

31.5

32.0

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1,309

1,310

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Date

Pumping Well 6 Manual Data

Pumping Well 6 Transducer Data

Pumping Well 6 Transducer Data (Adjusted for Barometric Efficiency)

48-Hour Pumping Test at Well 6

Barometric Pressure

FIG

. 2

Hydrogeologic Assessment Organ Pipe Cactus National Monument

PUMPING WELL 6

(NEW NORTH WELL)

HYDROGRAPH

December 2021 107854-001

FIG. 2SHANNON & WILSON, INC.

Geotechnical and Environmental Consultants

NOTES

1. The Well 6 pumping test was conducted between 11/16/21 09:30 and 11/18/21 09:30, average 55.0 gpm.

2. Well 6 is approximately 8 inches in diameter.

3. Well 6 grade elevation is approximately 1,664 feet.

4. gpm = gallons per minute; NAVD88 = North American Vertical Datum of 1988

5. Black and white reproduction of this color original may lead to incorrect interpretation.

I:\EF\SEA\107000s\107854 Organ Pipe NM\pumping test\Data\Analysis\OldNorthWell5_Hydrograph_pvh.xlsx Date:1/5/2022

30.0

30.5

31.0

31.5

32.0

32.5

33.0

33.5

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1,309

1,310

1,311

1,312

11/15/21 11/16/21 11/17/21 11/18/21 11/19/21 11/20/21

Ba ro m et ric P re ss ur e

(fe et o f w at er

Ap pr ox im at e

G ro un dw at er

E le va tio n (fe et N

AV

D

Date

Observation Well 5 Manual Data

Observation Well 5 Transducer Data

48-Hour Pumping Test at Well 6

Observation Well 5 Transducer Data (Adjusted for Barometric Efficiency) Barometric Pressure

FIG

. 3

Hydrogeologic Assessment Organ Pipe Cactus National Monument

OBSERVATION WELL 5

(OLD NORTH WELL)

HYDROGRAPH

December 2021 107854-001

FIG. 3SHANNON & WILSON, INC.

Geotechnical and Environmental Consultants

NOTES

1. The Well 6 pumping test was conducted between 11/16/21 09:30 and 11/18/21 09:30.

2. Well 5 is approximately 43 feet from Well 6.

3. Well 5 grade elevation is approximately 1,665 feet.

4. Transducer data collected prior to 11/16/21 8:47 were not barometrically compensated, and a different water level meter was used on 11/15/21 than for other measurements.

5. NAVD88 = North American Vertical Datum of 1988

6. Black and white reproduction of this color original may lead to incorrect interpretation.

I:\EF\SEA\107000s\107854 Organ Pipe NM\pumping test\Data\Analysis\OldSouthWell4_Hydrograph_pvh.xlsx Date:1/5/2022

29.0

29.5

30.0

30.5

31.0

31.5

32.0

32.5

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1,308

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1,310

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D

Date

Observation Well 4 Manual Data

Observation Well 4 Manual Data (Adjusted for Barometric Efficiency)

48-Hour Pumping Test at Well 6

Barometric Pressure

FIG

. 4

Hydrogeologic Assessment Organ Pipe Cactus National Monument

OBSERVATION WELL 4

(OLD SOUTH WELL)

HYDROGRAPH

December 2021 107854-001

FIG. 4SHANNON & WILSON, INC.

Geotechnical and Environmental Consultants

NOTES

1. The Well 6 pumping test was conducted between 11/16/21 09:30 and 11/18/21 09:30.

2. Well 4 is approximately 297 feet from Well 6.

3. Well 4 grade elevation is approximately 1,661 feet.

4. The transducer would not pass below about 100 feet deep, so only manual water levels were collected.

5. NAVD88 = North American Vertical Datum of 1988

6. Black and white reproduction of this color original may lead to incorrect interpretation.

I:\EF\SEA\107000s\107854 Organ Pipe NM\pumping test\Data\Analysis\Distance_DD_pvh.xlsx Date:1/5/2022

Pumping Well 6, 1.23

Observation Well 5, 0.57

Observation Well 4, 0.38

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0.1 1 10 100 1000

Ap pr ox im at e

D ra w do w n at E nd o f 4 8-

H ou r T es t ( fe et

Approximate Distance from Center of Well 6 (feet)

Drawdown, Adjusted for Estimated Barometric Efficiency

Log. (Drawdown, Adjusted for Estimated Barometric Efficiency)

FIG

. 5

Hydrogeologic Assessment Organ Pipe Cactus National Monument

DISTANCE-DRAWDOWN PLOT

WELL 6 PUMPING TEST

December 2021 107854-001

FIG. 5SHANNON & WILSON, INC.

Geotechnical and Environmental Consultants

NOTES

1. The Well 6 pumping test was conducted between 11/16/21 09:30 and 11/18/21 09:30.

2. Drawdown values measured at or near the end of the 48-hour Well 6 are provided here, adjusted for estimated barometric efficiencies.

3. Distances from calculations based on 'Final As Built Drawings' (Well 6) and Google Earth estimated locations (Wells 4 and 5).

Slope (s) = -0.29 ft / log cycle Q = 55 gpm T = 528Q/abs(s) = 528(55)/0.29 = 100,138 gpd/ft = 13,386 ft2/day

Log fit: y = -0.125ln(x) + 1.096 At y = 0, x = 6425 ro = 6425 ft S = 0.3Tt/r0

2 = 0.3(100,138)(2)/(6425)2 = 0.0015

Figure 6 – New Well Recommended Location Map

Organ Pipe Cactus National Monument Water Supply Well DRAFT Hydrogeologic Assessment

107854-001 January 2022 A-i

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Appendix A: Well Information

Appendix A

Well Drilling Logs, Construction Reports, Drawings, and Historical Pumping Test Data

CONTENTS

A-1: Well 6 Driller Report, Well Log, and Well Design

A-2: Well 6 2019 Well Test Report

A-3: Well 5 1974 Pumping Test Data

A-4: Well 4 Well Schedule and Driller Log

A-5: Well 4 1974 Pumping Test Data

II)

PUMP CURVE PUMP DIMENSIONS

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STEEL CASING EXTENDED A

MINIMUM OF 12" ABOVE TOP OF

CONCRETE SLAB.

SOUNDING TUBE 1.25" ID. MIN.

PVC SCH 40, BELL -END, GLUED

6'x6'x8" CONCRETE PAD

CONCRETE SURFACE SEAL

20' eaow GRADE MIN.

1 o• STEEL CASING

20' BELOW GRADE MIN. _____,,.,

1/4" THICK

2• PVC SCH 80

2• GALVANIZED STEEL PIPE, 5 LF

WRAP IN 20 MIL PVC TAPE

PITLESS ADAPTER

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1. ROCK FORMATIONS REQUIRED - ADDITIONAL WELL

DEPTH TO BE 550 FOOT.

2. THE BOREHOLE WAS ROUND, PLUMB AND TRUE TO

LINE. THE VERTICAL ALIGNMENT OF THE BOREHOLE AND

PERMANENT CASING SHALL PERMIT A 20-FOOT LENGTH OF PIPE,

HAVING A DIAMETER TWO INCHES SMALLER THAN THE

PERMANENT WELL CASING, WAS LOWERED AND RAISED IN THE

HOLE WITHOUT BINDING. THIS TEST WAS CONDUCTED WHILE

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SALVAGE IF POSSIBLE,

CLEAN AND REUSE

'I'. , .. !�;+----PIPE FROM WELL #5

�-----BENTONITE PELLEfS

1/8" TO 3/16" GRAVEL

PACK

SCREEN: 8" DIAMETER

JOHNSON SCREENS TYPE 304

STAINLESS STEEL CONTINUOUS

SLOT V-WlRE-WRAPPED WAS

INSTALLED, 100 SLOT, 0.100"

OPENING,

�!---�200

LF

.,A.._..A-...,_A-..._A-...-, 10-40 GPM PUMP,

GRUNDfOS 45S150-28 l-----

CENTRALIZERS WERE INSTALLED

ABOVE AND BELOW SCREEN

SECTION, WELD #4 REBAR HOOPS

TO El)GE OF BOREHOLE, 60'

APART, 6 PER UNIT. (TYP.)

T---,o· OF BLANK CASING 14 3/4"

BOREHOLE WITH WaDED END-CAP WAS INSTALLED

RECORD DRAWING PIPE BEDDING AND TRENCH BACKFILL

WARNING TAfE NATIVE BACKFILL

95% COMPACTION

2. THE PUMP SHALL WAS JOINED TO THE PIPE

COLUMN USING A STAINLESS STEEL NIPPLE CONNECTED TO

A HEAVY GALVANIZED COUPLING, WITH THE THREADS

BETWEEN THESE TAPED VERY WELL A TORQUE

ARRESTOR AND CHECK VALVE WAS INSTALLED ABOVE

THE PUMP. THIS WAS INSPECTED BY THE COR OR

PROJECT INSPECTOR PRIOR TO INSTALLATION IN WELL.

3. CHECK VALVE WAS INSTALLED AT THE TOP or COLUMN

PIPE AND AT EVERY 200' INTERVAL.

4. THE POWER CABLE AND SOUNDING TUBE WAS

SECURELY ATTACHED TO THE PUMP DISCHARGE PIPE AT

10-FOOT INTERVALS.

5. SCREEN USED WAS - JOHNSON SCREENS TYPE 304

STAINLESS STEEL CONTINUOUS SLOT V-WIRE-WRAPPED,

100 SLOT, 0.1 oo· OPENING. CENlRALIZERS WERE INSTALLED ABOVE AND BELOW SCREEN SECTION, wao f4

REBAR HOOPS TO CARBON STEEL CASE, TO EDGE OF

BOREHOLE, 60' AfART, 6 PER UNll

FINISHED GRADE

REVISION 1

FOR CONSTRUCTION

iG!'IQj £/l

66fl5@

VAO!M

RINBERG

ELECTRICAL CONDUIT

PVC SCH 40

:z :l!

�,�, a�ft

�ONA, \j. < ��he� Obj��, 100% ANAL

FOR CONSTRUCTION

Mork Sheet REVISION Dole Initial DESIGNED:

C 2 A �3/11 WG WG

C2 0 &/l.lftl WG !iiilstlE•18°•1 -I e----+---+--------+-c---+-------1 LN. WG r---+-C-2 �---1 ___ -+-lft4/'JD--+-W

-----1

G TECH. REVIEW:

G1 2 - RECORD DRAWING 2! GRC WG

□""'AT=-E,----tr---+---+-- - - - - --+---+-------1

1/14/2020

SUB SHEET NO.

C2

MAGNETIC LOCATOR TAfE

T

BEDDING SAND,

,\.... k. · ..,.,.· .• _., �

90% COMPACTION

TRACER

. ii :

. N /

WIRE

·_ .. •-�. -�·oH:�.·. . ' .

12" MIN

i--18" MIN-�

TITLE OF SHEET

WELL DESIGN

4" MIN.

2" PVC SCH 80

WATER LINE

DRAWING NO.

PKG, SHEET 2 NO.

-0 _ 01' ;R:6

REPLACE PRIMARY PARK WATER SUPPLY - WELL #6

CONSTRUCTION

ORGAN PIPE CACTUS NATIONAL MONUMENT

174955A

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N Important Information

Important Information About Your Geotechnical/Environmental Report

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CONSULTING SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES AND FOR

SPECIFIC CLIENTS.

Consultants prepare reports to meet the specific needs of specific individuals. A report prepared for a civil engineer may not be adequate for a construction contractor or even another civil engineer.

Unless indicated otherwise, your consultant prepared your report expressly for you and expressly for the purposes you indicated. No one other than you should apply this report for its intended purpose without first conferring with the consultant. No party should apply this report for any purpose other than that originally contemplated without first conferring with the consultant.

THE CONSULTANT’S REPORT IS BASED ON PROJECT-SPECIFIC FACTORS.

A geotechnical/environmental report is based on a subsurface exploration plan designed to consider a unique set of project-specific factors. Depending on the project, these may include the general nature of the structure and property involved; its size and configuration; its historical use and practice; the location of the structure on the site and its orientation; other improvements such as access roads, parking lots, and underground utilities; and the additional risk created by scope-of-service limitations imposed by the client. To help avoid costly problems, ask the consultant to evaluate how any factors that change subsequent to the date of the report may affect the recommendations. Unless your consultant indicates otherwise, your report should not be used

(1) when the nature of the proposed project is changed (for example, if an office building will be erected instead of a parking garage, or if a refrigerated warehouse will be built instead of an unrefrigerated one, or chemicals are discovered on or near the site); (2) when the size, elevation, or configuration of the proposed project is altered; (3) when the location or orientation of the proposed project is modified; (4) when there is a change of ownership; or (5) for application to an adjacent site.

Consultants cannot accept responsibility for problems that may occur if they are not consulted after factors that were considered in the development of the report have changed.

SUBSURFACE CONDITIONS CAN CHANGE.

Subsurface conditions may be affected as a result of natural processes or human activity. Because a geotechnical/environmental report is based on conditions that existed at the time of subsurface exploration, construction decisions should not be based on a report whose adequacy may have been affected by time. Ask the consultant to advise if additional tests are desirable before construction starts; for example, groundwater conditions commonly vary seasonally.

Construction operations at or adjacent to the site and natural events such as floods, earthquakes, or groundwater fluctuations may also affect subsurface conditions and, thus, the continuing adequacy of a geotechnical/environmental report. The consultant should be kept apprised of any such events and should be consulted to determine if additional tests are necessary.

MOST RECOMMENDATIONS ARE PROFESSIONAL JUDGMENTS.

Site exploration and testing identifies actual surface and subsurface conditions only at those points where samples are taken. The data were extrapolated by your consultant, who then applied judgment to render an opinion about overall subsurface conditions. The actual interface between materials may be far more gradual or abrupt than your report indicates. Actual conditions in areas not sampled may differ from those predicted in your report. While nothing can be done to prevent such situations, you and your consultant can work together to help reduce their impacts. Retaining

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N your consultant to observe subsurface construction operations can be particularly beneficial in this respect.

A REPORT’S CONCLUSIONS ARE PRELIMINARY.

The conclusions contained in your consultant’s report are preliminary, because they must be based on the assumption that conditions revealed through selective exploratory sampling are indicative of actual conditions throughout a site. Actual subsurface conditions can be discerned only during earthwork; therefore, you should retain your consultant to observe actual conditions and to provide conclusions. Only the consultant who prepared the report is fully familiar with the background information needed to determine whether or not the report’s recommendations based on those conclusions are valid and whether or not the contractor is abiding by applicable recommendations.

The consultant who developed your report cannot assume responsibility or liability for the adequacy of the report’s recommendations if another party is retained to observe construction.

THE CONSULTANT’S REPORT IS SUBJECT TO MISINTERPRETATION.

Costly problems can occur when other design professionals develop their plans based on misinterpretation of a geotechnical/environmental report. To help avoid these problems, the consultant should be retained to work with other project design professionals to explain relevant geotechnical, geological, hydrogeological, and environmental findings, and to review the adequacy of their plans and specifications relative to these issues.

BORING LOGS AND/OR MONITORING WELL DATA SHOULD NOT BE SEPARATED

FROM THE REPORT.

Final boring logs developed by the consultant are based upon interpretation of field logs (assembled by site personnel), field test results, and laboratory and/or office evaluation of field samples and data.

Only final boring logs and data are customarily included in geotechnical/environmental reports.

These final logs should not, under any circumstances, be redrawn for inclusion in architectural or other design drawings, because drafters may commit errors or omissions in the transfer process.

To reduce the likelihood of boring log or monitoring well misinterpretation, contractors should be given ready access to the complete geotechnical engineering/environmental report prepared or authorized for their use. If access is provided only to the report prepared for you, you should advise contractors of the report’s limitations, assuming that a contractor was not one of the specific persons for whom the report was prepared, and that developing construction cost estimates was not one of the specific purposes for which it was prepared. While a contractor may gain important knowledge from a report prepared for another party, the contractor should discuss the report with your consultant and perform the additional or alternative work believed necessary to obtain the data specifically appropriate for construction cost estimating purposes. Some clients hold the mistaken impression that simply disclaiming responsibility for the accuracy of subsurface information always insulates them from attendant liability. Providing the best available information to contractors helps prevent costly construction problems and the adversarial attitudes that aggravate them to a disproportionate scale.

READ RESPONSIBILITY CLAUSES CLOSELY.

Because geotechnical/environmental engineering is based extensively on judgment and opinion, it is far less exact than other design disciplines. This situation has resulted in wholly unwarranted claims

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N being lodged against consultants. To help prevent this problem, consultants have developed a number of clauses for use in their contracts, reports, and other documents. These responsibility clauses are not exculpatory clauses designed to transfer the consultant’s liabilities to other parties;

rather, they are definitive clauses that identify where the consultant’s responsibilities begin and end.

Their use helps all parties involved recognize their individual responsibilities and take appropriate action. Some of these definitive clauses are likely to appear in your report, and you are encouraged to read them closely. Your consultant will be pleased to give full and frank answers to your questions.

The preceding paragraphs are based on information provided by the ASFE/Association of Engineering Firms Practicing in the Geosciences, Silver Spring, Maryland