HomeMy WebLinkAbout106 MA 23 Lost Creek Packet
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LINCOLN COUNTY PLANNING & ZONING COMMISSION
STAFF REPORT
Major Subdivision Preliminary Plat
HEARING TIME AND DATE: 6:00 p.m. June 21, 2023
LOCATION: Lincoln County Courthouse, Commissioner Boardroom 3rd Floor, Kemmerer,
Wyoming & Afton Planning & Development Office, 61 E. 5th Ave., Afton, Wyoming
FILE # 106 MA 23
APPLICANTS: WSP Partners, LLC
PROJECT NAME: Lost Creek Meadows Subdivision – Preliminary Plat
COMMUNITY PLAN AREA: Thayne
ZONING: Rural
PIN: 3418-172-00-038 & 3418-171-00-002
SURVEYOR: Surveyor Scherbel, Ltd.
PLANNER: Robert C. Davis
_____________________________________________________________________________________
PROPOSAL: To subdivide approximately 128.43 acres into 25 residential lots in the Rural zone at a
potential density of .389 units/acre. Each lot will have individual wells, and individual septic systems that
meet Wyoming DEQ Standards.
The site is adjacent to single family residential uses to the north, west and south and agricultural uses
directly to the east. A 25-foot agricultural buffer has been provided on the east boundary. The site will be
accessed from County Road # 12-419 Ross County Road. The subdivision provides two ingress and
egress points and meets International Fire Code standards.
LOCATION: Property is just 1.12 miles south of the municipal boundary of the Town of Star Valley
Ranch and 1.06 miles northeast of the Town of Thayne in Section 19, Township 34 North, Range 118
West.
_____________________________________________________________________________________
EXHIBITS:
1. Application
2. Preliminary Plat
3. Vicinity Map
4. Draft Development Agreement
5. Agency Correspondence
_____________________________________________________________________________________
PLANNING STAFF RECOMMENDATION:
Planning staff recommends that the Planning and Zoning Commission send a recommendation of
APPROVAL to the Board of County Commissioners for File # 101 MA 23 a Major Subdivision
Preliminary Plat, with:
● Findings of Approval A thru C.
● Conditions of Approval 1 thru 8.
● A Recommendation for the Board Chairman to sign the Development Agreement.
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Relevant Issues - Lost Creek
Lots 1-6 have Lost Creek running through the North end. The Preliminary Plat reflects a 50-foot setback
from the creek for Lots 1- 6.
Ross Road
The subdivision will require Ross Road to be improved. The north 600 feet of Ross Road (County Road
12-419) right-of-way is only 30 feet wide. The developer has title to the 30 feet east of the county right-
of-way and is willing to convey title to Lincoln County in order to complete the county road. The
conveyance would be completed simultaneously with the filing of the final plat. The category of Ross
Road was changed from Primitive to Standard at a May 16, 2023 Public Hearing.
As per a Public Hearing on May 16, 2023, the Commissioners moved to amend Ross County Road 12-
419 with options for Category # 1, to change the category of the road from a primitive road to a standard
road.
Option #1. Change the Category of Ross Road from Primitive to a Standard Road
a. Rights-of-way for County Roads shall not be less than sixty (60) feet in width
and all proper easements, deeds or dedications shall be secured before the
road will be accepted and the category changed. WSP Partners, LLC will work
with Lincoln County to secure a sixty (60) foot easement for the County Road.
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b. The County will maintain the County Road to the end of the Lost Creek
Subdivision. The reason for this is there is not a sixty (60) foot right-of-way
south of the development.
c. The County continues to work on connectivity from Lost Creek County
Road 12-120 to Thayne Bedford County Road 12-122. This is as per the
Master Transportation Plan. Work to continue to obtain 60’ ROW for the
entire length of the County Road.
Upgrades for Ross Road will be necessary. The road will need to be 26 feet on top with 8" Subgrade and
4" Crushed Base. The existing culvert may need an extension due to the widening of the road. The
County will accept a "Hammerhead" for a turnaround.
It was observed the conduit placed in the County Right-of-Way was exposed and not at the minimum
depth of 36", as required. A license is required for the conduit to be placed in the Right-Of-Way and
since a license was not granted, the applicant should be fined.
Subdivision Road
Ross Loop Road was constructed without a
permit and according to LUR 6.28 (D)
Enforcement, the applicant should be fined for
this as well. The road will need to be
improved to a 26-foot width with two 12-foot
lanes with 1 (one) foot shoulders. In addition,
the right angle 90-degree curves will be
permitted but there must be consideration for
adequate sight distance.
The applicant was required to adjust the
frontage to the loop road of Lot 1 in order to
meet the 38 feet frontage requirement when a
lot abuts a street as per LUR 6.11 Lot Design
Specifications. Lot 1 is a flag lot and the
access creates effectively a T-intersection.
The plat will show a shared easement for Lots
1 and 13 in order to accommodate better
access for those lots. Staff is recommending
giving a portion of the Lot 13 easement to Lot
1 and to also provide Lot 25 with the ability to
have access for a better driveway design.
As per LUR 6.9 Driveway Access, adequate
site distance shall be provided for all lots. The
County Engineer’s graphic on the left depicts
a site triangle which shall be placed on the
plat as an inset to help ensure that no
vegetation is to be planted within that triangle.
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Traffic Study
The applicant provided a traffic flow analysis for the proposed subdivision. For the north entrance to
Ross Road, the ADT at build out is projected to be 293 trips, the south entrance to Ross Road would
provide approximately 270 ADT trips and for a total of 563 average daily trips. This equates to roughly
34 to 56 trips during the peak hour.
Ground Water and Septic Systems
The proposed water system will consist of individual wells on each lot. The WDEQ studied the analysis
performed by Sunrise Engineering and required adjustments to the design in order to grant a non-adverse
recommendation which means the proposed subdivision meets the safety and adequacy requirements of
the WDEQ Chapter 23 Rules. Chapter 23 provides for the required analyses for nitrate loading, minimum
isolation distances and impacts on public drinking water supply wells in subdivisions. The proposed water
system has been found to be safe and adequate provided the water is treated and constructed to Wyoming
State Engineer’s Office standards.
The proposed sewer system will be comprised of on-site septic tanks and leach field. Notes have been
added to the Preliminary Plat for both the groundwater and septic concerns.
PLANNING STAFF RECOMMENDATION FINDINGS:
A. The proposed subdivision, with conditions, is consistent with the provisions W.S. 18-5-301 through
W.S. 18-5-315.
B. The proposed subdivision is consistent with goals and objectives of the Lincoln County
Comprehensive Plan, including Section IV Land Use Objective 1. Create Land Use Regulations that
promote the responsible and orderly development of Lincoln County.
C. The proposed subdivision, with conditions, is consistent with the standards and procedures of these
Lincoln County Land Use Regulations, including:
a. Residential Density Standards; Chapter 6 Table: 6.1 for Major Subdivisions in the Rural
Zone.
CONDITIONS OF APPROVAL:
1. Significant alteration of the project shall require additional permitting.
2. A Weed Control Plan shall be developed in conjunction with Lincoln County Weed & Pest.
3. The conveyance the Ross Road easement to Lincoln County shall be completed simultaneously
with the filing of the Final Plat.
4. Ross Road shall:
a. Be 26 feet wide with 8-inch sub-base aggregate and 4 inches of crushed coarse aggregate
WYDOT Grading W.
b. Establish a drainage ditch on the west side.
c. Establish a Hammerhead turnaround.
d. Magnesium Chloride shall be applied to Ross Road for dust abatement.
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e. Obtain a Right-of-Way License for the conduit and the conduit shall meet a minimum 36”
deep.
5. Show on the Final Plat a shared easement for Lots 1 and 13 and also provide for Lot 25 the ability
for better access to a driveway through an easement.
6. Developer and County shall enter into a Development Agreement to ensure installation of
subdivision improvements and preparation of documents, including:
a. Construct Ross Road approved subdivision road with the minimum 26’ width travel lane
from County Road 12-419 with 8" Subgrade and 4" Crushed Base.
b. Extend the existing culvert at Ross Road along with the widening of the road.
c. Establish a drainage ditch on the west side.
d. Provide an acceptable turnaround preferably a Hammerhead turnaround at the southern end
of Ross Road near the project’s southern boundary.
e. Improved the existing conduit at Ross Road by placing it at the required 36-inch depth.
f. Install electrical power and communication lines.
g. Submittal of Water Distribution Plan to the State Engineer’s Office.
h. The Developer to purchase private road name signs and stop signs through Lincoln
County, Wyoming Planning and Development Office to assure standardization throughout
the County and developer will install after completion of improvements and subdivision
final approval.
i. Completion of irrigation lines and valves; enabling the development to shut off their
system for needed repairs without interruption of water delivery through Lost Creeks
Irrigation Main Line.
j. Survey monumentation; and
k. Development of either, a HOA, CCRs, Road Maintenance Agreement, Special
Improvement District, or Mutual Benefit Corporations that at a minimum:
i. Provide an entity for ongoing road maintenance including the collection of road
maintenance fees.
ii. Provides for a Water Master position to be in charge of maintenance and repair of
any irrigation line within the development with the exception of the Lost Creek
Irrigation Main Line which crosses the property in a north/south direction.
iii. Collects dues and fees per the Lost Creek Irrigation Company dues and fee
structure.
iv. Provide an entity for ongoing snow removal including the collection of snow
removal fees;
v. Ensure road maintenance and snow removal are maintained indefinitely.
vi. Be filed at the time of final plat filing, and bind all current and future owners to the
agreement.
7. Prior to Final Plat Application the improvements shall be installed and inspected by County
personnel.
a. Provide for final plat approval upon satisfaction of Development Agreement terms;
b. Developer Agreement shall be signed by all parties and filed with the Lincoln County
Clerk’s Office no later than 30 days after approval of the Preliminary Plat or the
application and approval shall be voided.
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8. A Plat Warning be included for sewage and water systems.
AGENCY CORRESPONDENCE:
The following agencies have provided comment:
Lincoln County Weed & Pest: Musk Thistle and Black Henbane has been found in the area. These
weeds are on the State noxious list and needs to be treated. The area also has a high probability of Leafy
Spurge. The applicant is expected to treat this. A weed management plan is required by the Development
Agreement.
Star Valley Conservation District: Due to large variation of groundwater levels in this area, SVCD
recommends soil cuts to determine groundwater levels. In areas in which groundwater is high, we
recommend an enhanced septic system. We also recommend that soil cuts be taken in the spring/early
summer when groundwater is highest. If soil cuts are done at other times know that static water level
fluctuates according to the amount of high-water runoff from year to year.
They also stated the degree of limitations for dwellings with and without basements is low is some areas
and not limited within the proposed subdivision. With regard to sewage disposal, they found that degree
for limitation for areas with Greyback Gravelly Loam Soil is very limited due to seepage which means
that the soil has one or more features that are unfavorable for the specified use. The WDEQ also
recognizes this limitation which has been reflected in the required Plat Warnings #2 and #3.
State Engineer's Office: No correspondence has been received at this time.
County Engineer: The County Engineer’s Office has contributed to this report.
The Lost Creek Irrigation Company (see next page)
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Wyoming DEQ: DEQ Recommend a Plat Warning with the following text:
1.6 miles northeast of Thayne, Wyoming
5± acres
4.65± acres 9.66 acres
3/2/2023
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DEVELOPMENT AGREEMENT
LOST CREEK SUBDIVISION
FILE NO. #106 MA 23
THIS AGREEMENT is made and entered into as of the ____ day of ______________, 2023 by
and between Lincoln County, Wyoming, hereinafter referred to as “County”, whose address is
421 Jefferson St., Suite 701, Afton, Wyoming, 83110, specifically Lincoln County Planning and
Development and WSP Partners, LLC., hereinafter referred to as OWNER/DEVELOPER”,
whose address is P.O. Box 725, Jackson, WY 83001.
WHEREAS, it is the intent and purpose of the OWNER/DEVELOPER to meet the conditions of
approval for File No.# 106 MA 23 Subdivision to subdivide approximately 128.43 acres into 25
lots as set forth in the Preliminary Plat; and
WHEREAS, the OWNER/DEVELOPER is the sole owner of the identified certain Property (see
Exhibit A) located in the County; and
WHEREAS, it is the intent and purpose of the OWNER/DEVELOPER and the County to enter
into this Agreement that will guarantee the full and satisfactory completion of the required
Improvements on the Property described in this Agreement and it is the intent of this Agreement
and the parties to satisfy the Improvement requirements and to provide for the approval of the
final plat application by the Lincoln County Board of County Commissioners and the final plat
recordation in the Office of the Lincoln County Clerk of Lost Creek Subdivision;
NOW THEREFORE, in consideration of the mutual covenants and conditions contained herein,
the parties agree:
Section 1. Definitions
1.1 SUBDIVISION: The subject of this Agreement, which is designated and identified as
File No. #106 MA 23 Lost Creek Subdivision on the Property described in Exhibit A in the
jurisdiction of Lincoln County, Wyoming. This definition shall include any and all future
mention to the term SUBDIVISION.
1.2 IMPROVEMENT: Any alteration to the land or other physical construction located on or
off the Property that is associated with this subdivision, building site, or development.
1.3 OWNER//DEVELOPER: means and refers to WSP Partners, LLC, whose address is P.O.
Box 725, Jackson, WY 83001, the party that owns and is developing the Property and shall
include and subsequent owner(s) or OWNER/DEVELOPER(s) of the Property.
1.4 PROPERTY: means and refers to the identified approximately 128.4300+/- acres of a
certain parcel(s) of Property located in Lincoln County, Wyoming, as described in Exhibit A.
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Section 2. Planned Improvements.
The OWNER/DEVELOPER shall, at its sole cost and expense, properly install and complete the
following required improvements:
● Subdivision Road:
o Construct Ross Road approved subdivision road with the minimum 26’ width
travel lane from County Road 12-419 with 8" Subgrade and 4" Crushed Base.
o Extend the existing culvert at Ross Road along with the widening of the road.
o Establish a drainage ditch on the west side of Ross Road.
o Provide an acceptable turnaround preferably a Hammerhead turnaround at the
southern end of Ross Road near the project’s southern boundary.
o Improved the existing conduit at Ross Road by placing it at the required 36-inch
depth.
● Submittal of Water Distribution Plan to the State Engineer’s Office
● Utilities:
o Install Electrical Power to each identified lot.
o Install Communication lines to each identified lot.
● Surveyor’s lot monuments as set forth in the Preliminary Plat attached hereto as Exhibit B.
● Disturbed areas shall be reseeded to avoid weed infestation and erosion.
● Road Signs: The Developer to purchase private road name signs and stop signs through
Lincoln County, Wyoming Planning and Development Office to assure standardization
throughout the County and developer will install after completion of improvements and
subdivision final approval.
OWNER/DEVELOPER agrees that these Improvements shall be installed in compliance with
Lincoln County Land Use Regulations Chapter 6 adopted by the County or other agencies
responsible for providing services to the Development.
Section 3. Sales or building permits. No lot shall be sold prior to final plat approval by the
Lincoln County Board of County Commissioners and recording by the Lincoln County Clerk.
Also, no building permits shall be issued by the County until final plat approval and recording.
Section 4. Schedule for Commencement and Completion of the Improvements. The
OWNER/DEVELOPER shall commence construction of the Improvements for SUBDIVISION
within two (2) years after the SUBDIVISION Preliminary Plat approval by the Lincoln County
Board of County Commissioners. The OWNER/DEVELOPER will complete construction of the
Improvements within three (3) years after approval of the Preliminary Plat. If
OWNER/DEVELOPER does not commence construction of the Improvements within two (2)
years or complete Improvements within three (3) years of the date of SUBDIVISION
Preliminary Plat approval by the Lincoln County Board of County Commissioners, the
preliminary plat approval for SUBDIVISION will be automatically revoked. At such time, the
OWNER/DEVELOPER must reapply for approval of SUBDIVISION under the then current
County subdivision regulations. If OWNER/DEVELOPER timely completes the Improvements
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and meets all of the conditions of approval set out in the Final Determination approving the
Preliminary Plat and improvements as outlined in this SUBDIVISION Agreement, a Final Plat
shall be signed and recorded.
Section 5. Control of trash, weeds, dust, erosion, and sedimentation. The
OWNER/DEVELOPER shall be fully responsible for all dust abatement, erosion, sedimentation,
weed, and trash control on the Property required by any County, State or Federal regulations.
OWNER/DEVELOPER shall use best management practices and industry standards for control.
Trash shall be contained at all times. The responsibilities in this Section shall run with the land
and shall therefore apply before, during, and until completion of Improvements.
Section 6. Permits. The OWNER/DEVELOPER is responsible for obtaining all 60’ right-of-
way, easements, access, excavation, and other permits and approvals required by local, State, or
Federal regulations.
Section 7. Inspections. The OWNER/DEVELOPER’s representatives shall make regular
inspections and maintain control of SUBDIVISION while it is under construction.
Representatives of the County shall have the right to enter upon the Property at any reasonable
time to inspect and to determine whether the OWNER/DEVELOPER is in compliance with this
Agreement. The OWNER/DEVELOPER shall permit the County and its representatives to enter
upon and inspect the Property at reasonable times. The OWNER/DEVELOPER will not
materially deviate from the Improvements required herein without the prior written approval of
the County, which approval will not be unreasonably withheld.
Section 8. Final Inspection and Approval of Improvements. The OWNER/DEVELOPER
shall notify the County when it believes that the Improvements have been fully and properly
completed and shall request final inspection and approval and acceptance of the Improvements
by the County. At the time of such notification to the County, OWNER/DEVELOPER shall
submit to County a set of “as built” plans and specifications, prepared by its engineer. The
County will provide interim and final inspection of the Improvements within a reasonable time
period after notification by the OWNER/DEVELOPER of completion and submission of “as
built” plans and specifications. Upon inspection, the County shall give written acceptance of the
Improvements or a written checklist of material deficiencies, such noted deficiencies shall be
specific as to location and shall specify, in detail, the necessary corrective action to be taken by
the OWNER/DEVELOPER. Upon approval of the final inspection, the County shall notify
OWNER/DEVELOPER of its acceptance of the Improvements.
Section 9. Warranty of the Improvements. The OWNER/DEVELOPER warrants the prompt
and satisfactory correction of all defects and deficiencies, for both materials and workmanship,
in the Improvements that occur or become evident within one year. If such defect or deficiency
occurs or becomes evident during such period, then the OWNER/DEVELOPER shall, within
thirty (30) days after written demand by the County to do so, correct it or cause it to be corrected.
If the defect or deficiency cannot be reasonably corrected within thirty (30) days after written
demand from the County, the OWNER/DEVELOPER shall commence the correction of the
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deficiency within the thirty (30) day period and proceed with reasonable diligence to correct the
same or cause it to be corrected.
Section 10. Remedies. In the event the OWNER/DEVELOPER fails to perform any of the
terms, conditions or obligations in this Agreement or has not resolved a defect or deficiency
under this Agreement, the County, at its option, may exercise any rights and remedies it may
have under law. Furthermore, the County reserves the right, in its absolute discretion, to revoke
the OWNER/DEVELOPER’s approvals for SUBDIVISION. In the event of said revocation,
OWNER/DEVELOPER must reapply for approval of SUBDIVISION under the then current
County subdivision regulations.
Section 11. Default. If the OWNER/DEVELOPER fails to fully perform any of its obligations in
accordance with this Agreement, or fails or refuses to correct any defect or deficiency in the
Improvements required by this Agreement, then the OWNER/DEVELOPER shall be in Default
of this Agreement. Lincoln County shall notify the OWNER/DEVELOPER of the specific
Default or failing. If Default occurs, then Lincoln County shall be entitled to use any of the
Remedies in the preceding paragraph at its own discretion.
Section 12. Maintenance of Lots. OWNER/DEVELOPER hereby agrees that all unsold lots
shall be maintained by the OWNER/DEVELOPER at the OWNER/DEVELOPER’s sole
expense.
Section 13. Maintenance of Roads and Irrigation Lines. OWNER/DEVELOPER hereby
agrees that they will create a binding document either a HOA, CCRs, Road Maintenance
Agreement, Special Improvement District, or Mutual Benefit Corporations that at a minimum:
a) Provide an entity for ongoing road maintenance including the collection of road
maintenance fees.
b) Provides for a Water Master position to be in charge of maintenance and repair of any
irrigation line within the development with the exception of the Lost Creek Irrigation
Main Line which crosses the property in a north/south direction.
c) Provides for completion of irrigation lines and valves; enabling the development to shut
off their system for needed repairs without interruption of water delivery through Lost
Creeks Irrigation Main Line.
d) Collects dues and fees per the Lost Creek Irrigation Company dues and fee structure.
e) Provide an entity for ongoing snow removal including the collection of snow removal
fees.
f) Ensure road maintenance and snow removal are maintained indefinitely.
g) Be filed at the time of final plat filing, and bind all current and future owners to the
agreement.
Section 14. Binding Upon Successors. This Development Agreement shall be binding upon and
inure to the benefit of the parties’ respective heirs, successors, assigns and personal
representatives.
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Section 15. Notices. Any written notices required herein shall be deemed delivered to the
addressee when delivered in person on a business day at the address set forth below or on the
third day after being deposited in the United States mail, for delivery by properly addressed,
postage prepaid, certified or registered mail, return receipt requested, to the address set forth
below.
Notices to the County shall be addressed to, or delivered at, the following address:
Lincoln County Board of County Commissioners
ATTN: Planning Director
Planning and Development Office
421 Jefferson St., Suite 701
Afton, Wyoming, 83110
Notices to the OWNER/DEVELOPER shall be addressed to, or delivered at, the following
address:
WSP Partners, LLC
P.O. Box 725
Jackson, WY 83001
Section 16. Indemnification.
A. No Liability for County Approval or Denial. The OWNER/DEVELOPER acknowledges
and agrees (1) that the County is not, and shall not be, in any way liable for any damages, loss or
injuries whatsoever, including attorney fees, that may be sustained as the result of the County’s
issuance or denial of any permits, inspections, approvals or acceptances of the Improvements or
use of any portion of the Improvements, and (2) that the County’s issuance or denial of any
permits, inspections, approvals or acceptances does not, and shall not, in any way be deemed to
insure the OWNER/DEVELOPER, or any of its heirs, successors, assigns, tenants, or licensees
or any third party, against damage or injury of any kind.
B. Indemnification. Except as provided below, the OWNER/DEVELOPER agrees to, and
does hereby, indemnify the County, and all of its elected and appointed officials, officers,
employees, agents and representatives from any and all claims, costs and liability of every kind
and nature that may be asserted at any time against any such parties for injury or damage
received or sustained by any person or entity in connection with (1) the County’s review of,
denial, or approval of any plans, including those for the Improvements, (2) the inspection or
issuance of any approval or acceptance of Improvements, (3) the SUBDIVISION, construction,
maintenance or use of any portion of the Improvements and (4) the performance by the
OWNER/DEVELOPER of its obligations under this Agreement and all related Agreements. The
indemnification required herein shall include, but not be limited to, any costs of defense incurred
by the indemnified parties including attorney fees and expert witness fees.
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Section 17. Amendments or Alterations. Any changes, omissions, modifications, revisions,
additions or amendments to this Development Agreement shall be incorporated by written
instrument, executed and signed by all parties.
Section 18. Severability. The invalidity or unenforceability of any provision of this Agreement
shall not affect the other provisions hereof and this Agreement shall be construed in all respects
as if such invalid or unenforceable provisions were omitted.
Section 19. Filing. The County shall have this Agreement recorded in the Office of the Lincoln
County Clerk.
Section 20. Authority to Execute. The County hereby warrants and represents to the
OWNER/DEVELOPER that the persons executing this Agreement on its behalf have been
properly authorized to do so by the Board of County Commissioners. The
OWNER/DEVELOPER hereby warrants and represents to the County (1) that it is the owner of
record of the Property or the owner’s authorized representative, (2) that it has the right, power,
and authority to enter into this Agreement and to agree to the terms, provisions, and conditions
set forth herein and to bind the subdivision as set forth herein, (3) that all legal action needed to
authorize the execution, delivery, and performance of this Agreement have been taken, and (4)
that neither the execution of this Agreement nor the performance of the obligations assumed by
the OWNER/DEVELOPER hereunder will (i) result in a breach or default under any Agreement
to which the OWNER/DEVELOPER is a party or to which it or the subdivision is bound or (ii)
violate any statute, law restriction, court order, or Agreement to which the
OWNER/DEVELOPER or the subdivision is subject.
Section 21. Regulations. The OWNER/DEVELOPER agrees to abide by all regulations, laws
and codes of Lincoln County, the State of Wyoming, and the Federal Government.
Section 22. Applicable Law/Venue. The construction, interpretation, and enforcement of this
Agreement shall be governed by the laws of the State of Wyoming. The Courts of the State of
Wyoming shall have jurisdiction over this Agreement and the parties, and the venue shall be the
Third Judicial District, Lincoln County, Wyoming.
Section 23. Insurance. OWNER/DEVELOPER shall procure, and at all times maintain, general
liability insurance to protect from claims for damages because of negligence or bodily injury,
including but not limited to death and damages to property, all with coverage limits of no less
than one million dollars ($1,000,000.00). Said insurance will also provide coverage to fulfill the
OWNER/DEVELOPER’s indemnification requirements set forth herein and be obtained before
beginning construction. Upon request, OWNER/DEVELOPER agrees to provide a certificate of
liability insurance to County evidencing said limit.
Section 24. Entirety of Agreement. This Agreement sets forth all promises, inducements,
agreements, condition and understandings between OWNER/DEVELOPER and County relative
to the subject matter hereof, and there are no promises, agreements, conditions or understanding,
either oral or written, express or implied, between OWNER/DEVELOPER and County, other
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than as are stated herein. All Exhibits referenced herein are incorporated in this Agreement as if
set forth in full including all text information in the Exhibits. In the event of any conflict of
terms in this Agreement and any Exhibits, the terms of this Agreement shall control. Except as
herein otherwise provided, no subsequent alteration, amendment, change or addition to this
Agreement shall be binding upon the parties hereto unless reduced to writing and signed by them
or their successors in interest or their assigns.
Section 25. No Waiver of County Rights. No waiver of any provision of this Agreement will be
deemed to constitute a waiver of any other provision nor will it be deemed to constitute a
continuity waiver unless expressly provided for; nor will the waiver of any default under this
Agreement be deemed a waiver of any subsequent default or defaults of the same type. The
County’s failure to exercise any obligation under this Agreement will not constitute the approval
of any wrongful act by the OWNER/DEVELOPER or the acceptance of any Improvement.
OWNER/DEVELOPER acknowledges that Lincoln County reserves the right to revoke all
approvals for SUBDIVISION upon failure to comply with SUBDIVISION conditions of
approval, upon any of the violations of Lincoln County Land Use Regulations, or for
misrepresentations or material omissions made to the Lincoln County Planning and Development
Office or Board of County Commissioners.
Section 26. Sovereign Immunity. The County does not waive sovereign immunity by entering
into this Agreement and specifically retains immunity and all defenses available to it pursuant to
law, including government immunity.
Section 27. Effective Date. This Agreement shall become valid and binding only upon its
approval by the Lincoln County Board of County Commissioners and shall be effective on the
date first written above.
IN WITNESS WHEREOF, the parties to this Agreement through their duly authorized
representatives have executed this Agreement on the days and dates set out below and certify
that they have read, understood, and agreed to the terms and conditions of this Agreement.
LINCOLN COUNTY
________________________________ Date: ______________________
_________________________, Chair
Board of Lincoln County Commissioners
Attest:
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________________________________
April Brunski
Lincoln County Clerk
OWNER/DEVELOPER
________________________________ Date: ______________________
Joey Parker
of WSP Partners, LLC, a Wyoming limited liability company
STATE OF WYOMING )
) ss
COUNTY OF LINCOLN )
The foregoing instrument was acknowledged before me by Joey Parker, Managing Members of
WSP Partners, LLC, a Wyoming limited liability company this ____ day of ______________
2023.
Witness my hand and official seal.
(SEAL)
_____________________________________
Notary Public
My Commission expires: ________________
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EXHIBIT A
DESCRIPTION OF PROPERTY
Lost Creek Subdivision
128.43+/- acres within Section 19, Township 34 North, Range 118 West, in, Lincoln County,
Wyoming.
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EXHIBIT B
APPROVED PRELIMINARY PLAT
See Attached
LOST CREEK MEADOWS SUBDIVISION
WATER & WASTEWATER SYSTEM ADEQUACY STUDY
October 2022
LOST CREEK MEADOWS SUBDIVISION
WATER & WASTEWATER SYSTEM ADEQUACY STUDY
October 2022
______________
Chris McDowell, P.G.Ryan J. Erickson, P.E.
WWC Engineering Sunrise Engineering, Inc.
1849 Terra Ave.47 E. 4th Avenue
Sheridan, WY 82801 Afton, WY 83110
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
i
WATER & WASTEWATER SYSTEM ADEQUACY STUDY
LOST CREEK MEADOWS SUBDIVISION
1.0 INTRODUCTION ....................................................................................... 1
1.1 General Information ............................................................................ 1
1.2 Study Process .................................................................................... 1
2.0 SITE INFORMATION .................................................................................. 2
2.1 Site Location and Topography .............................................................. 2
2.2 Hydrogeologic Setting ......................................................................... 2
2.3 Soil Types .......................................................................................... 5
2.4 Aquifer Characteristics......................................................................... 6
2.4.1 Depth to Groundwater, Aquifer Material and Flow Type ............... 6
2.4.2 Aquifer Thickness, Confinement, and Surface Interaction ............ 7
2.4.3 Transmissivity/Hydraulic Conductivity/Gradient/Porosity ............. 7
2.5 Existing Water Rights .......................................................................... 9
2.5.1 Surface Water ......................................................................... 9
2.5.2 Groundwater ........................................................................... 9
3.0 ON-SITE WASTEWATER SYSTEM ADEQUACY ................................................ 10
3.1 Percolation Rates .............................................................................. 10
3.2 Leach Field Size ................................................................................ 10
3.3 Separation Distances......................................................................... 11
3.4 Shallow Impermeable Layer ............................................................... 11
3.5 Slope of Ground Surface .................................................................... 11
3.6 Depth to Ground Water ..................................................................... 12
3.7 Aquifer Impacts ................................................................................ 12
3.8 Wastewater Conclusions and Recommendations ................................... 15
4.0 ON-LOT WATER WELL ADEQUACY ............................................................... 17
4.1 Water Quantity ................................................................................. 17
4.2 Water Quality ................................................................................... 17
4.3 Water System Conclusions and Recommendations ................................ 18
5.0 REFERENCES ............................................................................................ 19
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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FIGURES
APPENDIX A Water Quality Data
APPENDIX B Percolation Test Data
APPENDIX C Well Statements of Completion
APPENDIX D Water Rights Data
APPENDIX E Well Permits Within One Mile
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1.0 INTRODUCTION
1.1 General Information
The purpose of this study is to evaluate the impact, safety and adequacy of the proposed
wastewater treatment systems and water systems for the Lost Creek Meadows Subdivision. The
proposed subdivision is located approximately 1 mile south of the Town of Star Valley Ranch in
Lincoln County, Wyoming. The project area is located on the valley floor just east of Ross
County Road #12-419 within Section 17, Township 34 North, Range 118 West, 6th P.M. Lincoln
County, Wyoming.
The proposed subdivision consists of twenty-five (25) parcels totaling over approximately 129
acres, with a gross density of 5.14 acres each. Actual lot sizes will range from roughly 4.77 to
9.64 acres. The lots will be utilized for single-family residential use. A vicinity map of the project
area is shown as Figure 1,and a draft Preliminary Plat is shown as Figure 5.
Under the subdivision rules for the State of Wyoming and Lincoln County, studies must be
conducted to determine if the water and wastewater facilities for the proposed subdivision will
be safe and adequate. Individual on-site wastewater treatment systems are proposed for the
development. Also, individual wells for each lot are proposed for the Lost Creek Meadows
Subdivision.
1.2 Study Process
This study follows the requirements set forth in Sections 7 and 8 of the Wyoming Department
of Environmental Quality (WDEQ) Water Quality Rules and Regulations Chapter 23 (July
2012). This study will determine whether the proposed wastewater systems will be safe for the
surrounding environment and will be adequate for treatment of the anticipated wastewater
flows. This study will also determine whether the proposed individual wells will provide safe
water in adequate quantity and quality.
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2.0 SITE INFORMATION
2.1 Site Location and Topography
The Lost Creek Meadows Subdivision is located in the Lost Creek area south of Star Valley
Ranch near the east bench on the valley floor of Star Valley. The area has relatively flat
topography with an average grade of 3% generally draining west toward the Salt River. The
project area has no development and was previously used for agricultural purposes as irrigated
farmland. There are other single-family residences in the surrounding area, generally on lots of
similar size. The Salt River is roughly 3 miles to the west. The northern 6 lots of the proposed
subdivision are crossed by Lost Creek which is ephemeral and flows east to west.
2.2 Hydrogeologic Setting
As shown on Figure 2, the proposed subdivision is located on an area of coalescing alluvial fans
off the Salt River Range to the east and the alluvial deposits associated with the floodplain of the
Salt River. The Quaternary-age alluvium in this area is generally composed of unconsolidated
sand and gravel interbedded with clay and silt (Forsgren Associates & Weston Engineering
2009). The bedrock beneath these unconsolidated deposits is the Tertiary-age Salt Lake
Formation. The Salt Lake Formation is a complex stack of sedimentary rocks – sandstone, shale,
and conglomerate – of widely variable hydrogeologic characteristics, up to 1,000 feet thick
(Miller et al., 1996).Figure 2 also shows the locations of all wells within one mile of the
proposed subdivision.
The Wyoming Water Development Commission (WWDC) funded groundwater study for the
Town of Star Valley Ranch includes details on a test boring located in the SENE Sec 6 T34N,
R118W approximately 1.8 miles north of the proposed subdivision. In the WWDC test boring
the unconsolidated alluvial deposits were judged to be 100 ft. thick (Forsgren Associates &
Weston Engineering, 2009). Underlying the alluvium, the boring penetrated the underlying Salt
Lake Formation to a depth of 492 ft. The degree of consolidation appears to have been the
primary distinction between the two units. The WWDC test boring is one of the best described
penetrations near the proposed subdivision and is used as a reference for the general stratigraphy
and approximate thickness of formations in the region.
There are nearby water wells with lithologic logs that are located approximately 0.2 miles
southeast (P175293.0W), 0.2 miles southeast (P154393.0W), 0.75 miles southeast (P30432.0W),
and 0.3 miles (P96625.0W) to the northeast of the proposed subdivision. The lithologic log from
P175293.0W identifies gravel and clay layers consistent with descriptions of alluvial material in
the region from 0 to 240 ft which is the total depth of the well. The lithologic log of
P154393.0W identifies clay and gravel consistent with descriptions of alluvial material in the
region until 187 ft where they encountered “limestone ledging”. The lithologic log of
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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P30432.0W identifies gravel and clay layers consistent with descriptions of alluvial material in the
region until 240 ft where the driller encountered a layer of “solid rock”. The lithologic log of
P96625.0W identified clay and gravel and broken limestone and clay to a depth of 197 ft where
the driller encountered a “limestone ledge”. Well P175293.0W did not fully penetrate the
alluvium; however, in the other three wells the drillers all identified a rock layer that is likely the
base of the alluvium. These wells are further from the basin margin than the WWDC test boring
which may explain the thicker alluvial deposits at that location. Due to their proximity to the
proposed subdivision these wells have been used as analogs for the thickness of the alluvium in
the proposed subdivision.
Table 1 is a list of wells within half a mile of the proposed subdivision while a summary of all
permitted groundwater rights within one mile of the proposed subdivision is located in
Appendix E. A total of 77 active groundwater permits are within one mile of the proposed
subdivision and 28 active groundwater permits are within half a mile of the proposed
subdivision.
The contact between the alluvial deposits and the underlying Salt Lake Formation is indistinct in
this area as none of the lithologic logs for the wells in Table 1 include explicit reference to the
Salt Lake Formation. For the present report, we assume the unconsolidated aquifer extends to a
depth of approximately 200 ft beneath the proposed subdivision. (Detailed distinction between
the two units is not critical for the purposes of assessing water / wastewater suitability for this
project.)
In summary, the aquifer to serve as the water supply for the proposed subdivision consists of
the unconsolidated alluvial fan deposits off the mountains to the east, interlayered with the
alluvial deposits of the Salt River, which flows from south to north, west of the proposed
development. The underlying Salt Lake Formation provides a potential deeper aquifer should
the production of the overlying strata prove unsuitable at a specific location. The unconsolidated
deposits would also constitute the receiving strata for wastewater effluent from individual septic
systems.
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY 4
Table 1. Water Wells Within Half a Mile
Permit
Number
WR
Number
Priority
Date
Summary WR
Status Last Name Facility Name Uses Twn Rng Sec Qtr-Qtr
Total Flow
(CFS)/
Appropriation
(GPM)
Total
depth
(Ft)
Static
Water
Level
(Ft)
Well
Log
(Y/N)
Depth
Of
Pump
Principal
Water Bearing
Formation
Depth Top
Principal Water
Bearing
Formation
Depth Bottom
Latitude Longitude
167762.0 P167762.0W 05/20/2005 Complete CAPPS 4-C RANCH DOM_GW;
STK 034N 118W 18 NW1/4NE1/4 25 100 60 N 90 90 100 42.93795 -110.962317
61107.0 P61107.0W 06/01/1982 Complete HEINER HEINER #2 DOM_GW 034N 118W 07 SE1/4SE1/4 10 107 50 68 107 42.94081 -110.95577
72334.0 P72334.0W 04/21/1986 Complete QUINN QUINN #1 DOM_GW 034N 118W 17 NE1/4NE1/4 10 115 58 -1 -1 42.93725 -110.93644
98330.0 P98330.0W 02/08/1995 Complete ROBERTSON V=2 DOM_GW;
STK 034N 118W 18 SW1/4NE1/4 15 120 100 100 120 42.9335 -110.96066
170580.0 P170580.0W 11/09/2005 Complete SHANNONS WAY DOM_GW 034N 118W 18 NE1/4NW1/4 25 120 90 N 105 100 120 42.937883 -110.963467
75547.0 P75547.0W 09/11/1987 Complete ELLIS ELLIS #1 DOM_GW 034N 118W 17 NE1/4NE1/4 5 134 70 70 90 42.93725 -110.93644
147046.0 P147046.0W 09/17/2002 Complete ROBERTSON FLYING J DOM_GW 034N 118W 18 SW1/4NE1/4 15 135 80 130 135 42.9335 -110.96066
103204.0 P103204.0W 08/05/1996 Complete B&B #1 DOM_GW 034N 118W 17 SW1/4SW1/4 22 140 80 100 140 42.92628 -110.95098
168154.0 P168154.0W 06/08/2005 Complete BARKER ECHO DOM_GW 034N 118W 18 NE1/4NE1/4 20 140 100 N 135 135 140 42.937169 -110.955789
180975.0 P180975.0W 03/14/2007 Complete KUNZ #0501 DOM_GW 034N 118W 18 SE1/4NE1/4 15 140 80 N 135 139 140 42.9352 -110.9564
206788.0 P206788.0W 02/21/2017 Complete JOHNSON JOHNSON #1 DOM_GW;STK 034N 118W 18 SE1/4NE1/4 25 143 85 N 130 85 143 42.932549 -110.958089
204201.0 P204201.0W 07/21/2015 Complete JANSEN SNAPPY 1 DOM_GW 034N 118W 18 NE1/4NE1/4 18 158 95 N 158 95 158 42.93611 -110.95583
204545.0 P204545.0W 09/14/2015 Complete AUSTIN AUSTIN #1 DOM_GW;STK 034N 118W 17 SW1/4SW1/4 10 160 103 N 136 120 147 42.926667 -110.952778
175012.0 P175012.0W 05/22/2006 Complete EDWARDS E #1 DOM_GW 034N 118W 18 NE1/4NE1/4 25 180 60 N 170 140 180 42.936366 -110.954217
157203.0 P157203.0W 03/25/2004 Complete BARBER LOVEY 1 DOM_GW 034N 118W 17 NW1/4SW1/4 15 200 140 180 200 42.92992 -110.95096
159511.0 P159511.0W 06/14/2004 Complete BARFUSS BARFUSS #1 DOM_GW 034N 118W 17 NE1/4SW1/4 25 200 75 163 200 42.92993 -110.94613
212180.0 P212180.0W 04/22/2020 Complete HEINER Q & D HEINER #1 DOM_GW 034N 118W 17 NW1/4SW1/4 20 220 170 N 205 200 220 42.930833 -110.948889
172831.0 P172831.0W 01/23/2006 Complete BUTTERFIELD BUTTERFIELD #1 DOM_GW 034N 118W 17 NW1/4SW1/4 20 230 150 N 220 220 230 42.9291 -110.9493
96625.0 P96625.0W 08/08/1994 Complete JONES CHERIE'S WELL #1 DOM_GW 034N 118W 08 SW1/4SE1/4 10 240 170 210 240 42.94087 -110.94125
150302.0 P150302.0W 04/10/2003 Complete HOLCOMB 1 DOM_GW 034N 118W 17 NE1/4SW1/4 15 240 180 220 240 42.92993 -110.94613
175293.0 P175293.0W 06/16/2006 Complete LOWERY LOWERY #1 DOM_GW 034N 118W 17 NE1/4SW1/4 20 240 180 N 235 235 240 42.9312 -110.9449
183764.0 P183764.0W 11/13/2007 Complete HINTZE HINTZE #1 DOM_GW 034N 118W 17 NW1/4SE1/4 20 240 180 N 235 235 240 42.9303 -110.942117
204831.0 P204831.0W 11/06/2015 Complete BALK BALK #1 DOM_GW 034N 118W 17 NE1/4SW1/4 20 242 180 N 227 220 242 42.928819 -110.943831
206280.0 P206280.0W 09/27/2016 Complete BURNETT LOST CREEK RD 179 DOM_GW;STK 034N 118W 08 NE1/4SE1/4 20 260 190 N 0 220 260 42.943919 -110.938619
46038.0 P46038.0W 12/11/1978 Complete MCNINCH
TRUST J F WAGNER #1 DOM_GW 034N 118W 08 SE1/4SE1/4 22 280 240 240 280 42.94089 -110.93644
183709.0 P183709.0W 11/13/2007 Complete BERGSTROM R & C #1 DOM_GW 034N 118W 08 SW1/4SE1/4 25 280 221 N 270 260 280 42.940567 -110.9394
154393.0 P154393.0W 10/10/2003 Complete HILL HILL #1 DOM_GW 034N 118W 17 NW1/4SE1/4 25 300 187 240 300 42.92995 -110.94129
22468.0 P22468.0W 06/19/1973 Fully
Adjudicated
LOST CREEK
RANCHETTES SUB
WELL #1
MIS 034N 118W 08 SE1/4SE1/4 45 344 219 219 344 42.94089 -110.93644
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2.3 Soil Types
There are four major soil types present in the project area according to the NRCS Web Soil
Survey (https://websoilsurvey.nrcs.usda.gov) and Soil Survey of Star Valley (Soil Conservation
Service, 1976). The major soil types are Greyback Gravelly Loam (Gg); Huffline Silt Loam, 0 to
3 percent slopes (HuA); Thayne Gravelly Loam, 0 to 3 percent slopes (ThA); and Thayne
Gravelly Loam, 3 to 6 percent slopes (ThB). See Figure 3 for the soils map of the project area.
The soils survey contains the following information regarding these soils.
Greyback Gravelly Loam (Gg). The Greyback series consists of somewhat excessively
drained soils that formed in alluvium on alluvial fans and foot slopes. In a representative
profile the surface layer is grayish-brown gravelly loam about 7 inches thick. The subsoil
is brown gravelly loam about 11 inches thick. The substratum is light yellowish-brown
very gravelly sandy loam and very gravelly loamy sand or sand to a depth of 60 inches or
more. This nearly level to gently sloping soil is on alluvial fans, mainly in the lower valley
(the location of this project). Slopes are 0 to 6 percent. Permeability is moderate. Runoff
is slow and the hazard of erosion is slight. This soil is used for irrigated crops, for range,
as wildlife habitat, and for townsites. Approximately 19% of the project area is located in
this soil type.
Huffine Silt Loam, 0 to 3 percent slopes (HuA). The Huffine series consists of well-
drained soils that formed in wind-deposited silt or alluvium on alluvial fans. In a
representative profile the surface layer is brown silt loam about 7 inches thick. The upper
part of the subsoil is brown silt loam about 4 inches thick. The lower part of the subsoil
is brown silty clay loam about 20 inches thick. The substratum is brown very gravelly
loamy sand to a depth of 60 inches or more. This nearly level soil is on alluvial fans.
Permeability is moderate. Runoff is slow, and the hazard of erosion is slight. This soil is
used for irrigated crops, for range, and as wildlife habitat. Approximately 14% of the
project area is located in this soil type.
Thayne Gravelly Loam, 0 to 3 percent slopes (ThA). The Thayne series consists of
well-drained soils that formed in alluvium on alluvial fans. In a representative profile the
surface layer is dark grayish-brown loam about 12 inches thick. The subsoil is light olive-
brown gravelly loam about 12 inches thick. The substratum is pale-yellow very gravelly
loam to a depth of 60 inches or more. This nearly level soil is on alluvial fans.
Permeability is moderate. Runoff is slow, and the hazard of erosion is slight. This soil is
used for irrigated and dryland crops, for range, and for wildlife habitat. Approximately
36% of the project area is located in this soil type.
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Thayne Gravelly Loam, 3 to 6 percent slopes (ThB). This gently sloping soil is on
alluvial fans. The soil profile is similar to the one described as representative of the series
(listed previously), but the surface layer is gravelly loam. Permeability is moderate.
Runoff is slow, and the hazard of erosion is slight. This soil is used for irrigated and
dryland crops, for range, and for wildlife habitat. Approximately 31% of the project area
is located in this soil type.
No other soil types are mapped in the project area.
2.4 Aquifer Characteristics
2.4.1 Depth to Groundwater, Aquifer Material and Flow Type
There are 28 active groundwater permits within half a mile of the proposed subdivision
(Table 1). The depths to water reported for wells within a half a mile that are likely completed in
the alluvium (wells with a total depth of less than 200 ft) in the study area vary from 10 to 200 ft,
with an average depth to water of 83 ft.
Water flows westward towards the Salt River and the center of the basin. To some extent, the
depth to water in the alluvium is a function of proximity to the river, which is presumably the
base elevation for the local alluvial groundwater flow system. But the reported depths to water
can vary greatly depending on the depth at which the well is completed, the conditions under
which the measurement was taken (e.g. less than full recovery following testing), the season, and
simple errors. These are not quality-controlled data.
No information on seasonal variations of groundwater levels have been developed in the study
area. Given the normal cycles of recharge (including that provided by local flood irrigation),
groundwater highs are expected to occur in late summer and groundwater lows in late winter.
The elevation of the adjacent Salt River, 5,860 feet (i.e. 340 feet lower than the ground surface in
the middle of the proposed subdivision) likely provides a lower bound on the groundwater
elevation beneath the project area. (As discussed above, the variations in depth to water reported
with domestic well completions are likely the result of a combination of aquifer hydraulics and
seasonal fluctuations.)
The age and genesis of the alluvial deposits are consistent with the absence of known structures
of interest to the present study (e.g. faults, fracture zones, etc.). Nor are these deposits
conducive to the development of karst features. Groundwater flow will occur as flow through
porous media, although the permeability and porosity of individual strata will vary substantially.
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2.4.2 Aquifer Thickness, Confinement, and Surface Interaction
Subtraction of depths-to-water from total well depths calculate an average saturated interval of
60 feet for the wells likely completed in the alluvium (with a total depth of less than 200 feet)
within one half mile of the proposed subdivision as shown in Table 1. As many of these wells
do not fully penetrate the alluvium, the full saturated thickness of the alluvial aquifer is likely
greater than the calculated average, depending on local conditions. Additionally, the underlying
Salt Lake Formation is saturated in the area as well.
The clay and clay-rich layers discussed above likely serve as many local confining layers in the
alluvial aquifer. The alluvial deposits consist of a complex interbedding of sands, gravels and
clays and stratigraphic detail is insufficient to identify the lateral extent of such features. Pending
more detailed investigations, the overall aquifer is considered to be “semi-unconfined”. Surface
recharge infiltrates downward to eventually enter strata with useful water-bearing properties, but
that process is likely complex.
The vadose zone, through which recharge travels downward to reach the water table, is a mix of
gravel, sand, and clay strata, likely varying substantially in composition from place-to-place. The
average thickness of the unsaturated zone is 83 feet for the alluvial wells (less than 200 feet deep)
listed in Table 1.
Interaction between surface and groundwater consists of the infiltration of local precipitation,
snowmelt, and irrigation water to recharge the aquifer, general groundwater flow direction is
from east to west, and discharges from the aquifer to the Salt River (including supplying riparian
zone evapotranspiration).
2.4.3 Transmissivity/Hydraulic Conductivity/Gradient/Porosity
In general, “permit yield” may or may not reflect actual measured production for domestic wells
as many domestic wells are limited to 25 gpm by the Wyoming State Engineer’s Office (WSEO),
but most of the values on Table 1 are reported as “amount of water being pumped” on the
Statements of Completion. The average of these values is 19 gpm.
Some of the wells reviewed for which completion details were reported are simply completed as
open-ended casings, rather than providing opportunity for groundwater to enter the well
through perforations or screen sections. This is an inexpensive approach that has proven
adequate. It indicates relatively high permeability in the final stratum in that sufficient water
enters through the bottom of the well.
Table 2 compiles the scarce test data reported for which specific discharge rates and drawdown
values were reported with well completion forms. There were no reported pump test data for
the wells completed in the alluvium within 0.5 miles of the proposed subdivision therefore data
from the two pump tests conducted at the high flow irrigation well P2649.0W (approximately
0.75 miles to the north) were used. Transmissivity values are estimated using the pumping rate,
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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pumping time, and drawdown from the well completion reports. Driscoll (1986) developed
formulas to approximate the transmissivity for both confined and unconfined aquifers that are
based on generic assumptions about the aquifer and well test. Due to the quality of the data
reported on the well completion forms it is reasonable to use these assumptions and formulas to
approximate the transmissivity for these wells.
Table 2. Aquifer Test Data Extracted from WSEO Permit Files
Permit
Number
Rate
(gpm)
Drawdown
(ft)
Time
(hrs)
Specific
Capacity
(gpm/ft)
Transmissivity
(gpd/ft)
Aquifer
Thickness
(ft)
Hydraulic
Conductivity
(ft/day)
2649.0
(Test 1)1,190 45 3 26.44 39,600 135 39.2
2649.0
(Test 2)1,275 28 5 45.54 68,000 135 67.7
The “aquifer thickness” is poorly determined because the well does not fully penetrate the
alluvial aquifer. Listed in Table 2 is the total thickness of the specific water-bearing stratum in
which the well was screened as reported in the WSEO permit files. Due to the quality of the test
data, and in the interest of conservatism, the parameters calculated in Table 2 are the minimums
possible to produce the reported results.
In terms of productivity, these tests confirm that the alluvial aquifer is abundantly capable of
meeting the needs of individual residential lots. In terms of specific aquifer parameters, a
hydraulic conductivity of at least 39.2 ft/day is indicated, and the true value is probably
considerably larger.
Figure 4 is a potentiometric surface based on approximate groundwater elevations for select
wells for which the depth to water was reported upon well completion (dates and circumstances
vary) and for which the well has been located with sufficient accuracy to support estimation of
surface elevation. The former come from individual well Statements of Completion filed with
the WSEO; the latter are taken from topography maps.
Overall consideration of recharge/discharge relationships require that the groundwater gradient
be generally from east-to-west as precipitation and irrigation provide recharge across the aquifer
and regional groundwater discharge is to the Salt River. However, quantification of a meaningful
gradient is complicated by disparities in the reported data and the likely presence of multiple
water-bearing zones that are not fully integrated hydraulically. (There are both horizontal and
vertical gradients in the aquifer; lateral flow is being estimated using a composite horizontal
gradient.)
A groundwater gradient is approximated by calculating an average gradient between sets of wells
shown on Figure 4. The average gradient from eight sets of wells at various locations on
Figure 4 was calculated to be 0.018 ft/ft.
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Porosity of the saturated zone has not been directly assessed. An approximate value of 0.25 is
suggested based on the nature of the alluvial deposits (e.g. Sterrett, 2007).
2.5 Existing Water Rights
2.5.1 Surface Water
A water right search was conducted for the development area. The entire development area has
irrigation rights from Lost Creek or Baxter Creek through the Lost Creek Pipeline under Permit
No. 525 and Permit No. 16113. The lands are irrigated by a center pivot and wheel line systems.
A map and Certificates of Appropriation for these rights can be found in Appendix D.
A water right distribution map will be created to retain water rights within the development. The
rights for areas within the roadways will be either detached or abandoned. The distribution map
will be filed with the WSEO.
2.5.2 Groundwater
There are no existing wells located within the project boundaries.Appendix E lists all
groundwater rights of record within one mile of the proposed subdivision.
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3.0 ON-SITE WASTEWATER SYSTEM ADEQUACY
3.1 Percolation Rates
Five percolation tests were performed in the proposed project area in November 2021, one in
each soil type. Refer to Figure 3 and Appendix B for the location of the test holes and
percolation test data. The results from the five tests ranged from 2 to 13 min/inch. A “worst-
case” percolation rate of 13 min/inch will be used for this study.
The maximum allowable percolation rate for Lincoln County is 1 minute per inch and the
minimum allowable percolation rate is 60 minutes per inch. The percolation rates from the tests
are within Lincoln County and DEQ regulations. Pits dug for percolation tests were at depths
ranging from 3.2 feet to 4.3 feet. Also, a test pit was dug to a depth of 8 feet. No signs of
groundwater were detected at these depths. With minimum lot sizes of nearly 5 acres, there
should be no issue in finding a location with acceptable percolation qualities on each lot.
3.2 Leach Field Size
The size of leach field required for an on-site wastewater system depends upon the type of
buildings it will serve, the number of buildings, and the size of those buildings. It is anticipated
the Lost Creek Meadows Subdivision will be used for single-family residences. Lincoln County
and WDEQ regulations call for domestic sewage flows of 150 gallons per day per bedroom for a
single-family dwelling, with the flow declining slightly for each additional bedroom. Also, the
absorption system loading rate of 0.56 gallons per square foot per day is given for the
percolation rate of 13 min/inch.Table 3 shows the required leach field area for a 2-, 3-, or 4-
bedroom system using this loading rate.
Table 3. Required Leach Field Size
# of Bedrooms Peak Flow Rate (gpd)Req’d Leach Field Size (ft2)
2 280 500
3 390 696
4 470 839
Proposed lot sizes will range from 4.77 to 9.64 acres, with an average of just over 5 acres per lot
(including roads). Each lot will have an individual standard septic tank with leach field. The
minimum sized lot will be large enough to accommodate the required leach field area as well as a
replacement drain field area.
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3.3 Separation Distances
Lincoln County and Wyoming DEQ requires the following separation distances:
From To Septic Tank To Absorption System
Wells (including neighbors)50 100
Public Water Supply Well 100 200
Property Lines 10 10
Building Foundation (w/o foundation drains) 5 10
Building Foundation (w/ foundation drains) 5 25
Potable Water Pipes 25 25
Septic Tank --10
Stream or Surface Water (incl. intermittent) 50 50
Also, systems shall not be located beneath buildings, parking lots, roadways, or similarly
compacted areas.
Each lot in the Lost Creek Meadows Subdivision will have an on-lot individual standard septic
system. This subdivision will have an average lot size of roughly 5 acres and a minimum lot size
of about 4.77 acres, thereby meeting County requirements.
3.4 Shallow Impermeable Layer
Lincoln County regulations state an on-site small wastewater facility must be at least four feet
above any impermeable layer. Form U.W. 6 drill cutting logs were obtained from the WSEO for
wells in the vicinity of the subdivision, and the data reviewed to determine if any impermeable
layers were present. While there are layers of clay at various depths, there are no indications of a
shallow impermeable layer according to the well logs.
Soil percolation rate tests were performed within subdivision boundaries, resulting in a rate of 2
to 13 minutes per inch. A test pit was dug and observed in the project area to a depth of 8 feet.
No impermeable layers were observed.
Review of nearby well logs, percolation test data, and the development site shows no apparent
shallow impermeable layer which will cause problems with leach field effluent.
3.5 Slope of Ground Surface
The proposed development is located on the valley floor of the lower Star Valley and was
previously used as irrigated cropland. The slopes across the project area range from roughly 3%
to 4% from east to west. There will be no issues with siting of wastewater tanks and leach fields
due to ground slope.
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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3.6 Depth to Ground Water
Lincoln County and WDEQ regulations state that an on-site small wastewater facility must be at
least four feet above seasonally high ground water. No water was observed in the test pit to a
depth of 8 feet. As mentioned in Section 2.4.1, the average depth to groundwater from alluvial
wells in Table 1 is 83 feet.
3.7 Aquifer Impacts
Water quality data for the aquifer receiving septic system effluent are provided in Appendix A,
along with EPA Drinking Water Standards for reference (these standards are promulgated only
for public water supplies). Both the laboratory analysis and the widespread use of the alluvial
aquifer for area drinking water identify the aquifer as Class I under WDEQ regulations.
The impact of proposed individual wastewater disposal systems on the receiving aquifer has
been evaluated as per WDEQ Chapter 23, Appendices A, B and C:
Appendix A Calculations. The DEQ Chapter 23 Appendix A cumulative nitrate loading analysis
uses the following nitrogen mass balance equation (Wehrmann Model):
Co = (VbCb + ViCi + VsCs - VpCp) / (Vb + Vi + Vs - Vp)
where,
Co = diluted concentration of NO3- as N leaving the subdivision
Vb = volume of groundwater entering the subdivision from up gradient area
Cb = ambient concentration of NO3- as N contained in the groundwater entering the
subdivision
Vi = volume of precipitation infiltrating beneath the subdivision
Ci = concentration of NO3- as N contained in the infiltrating precipitation
Vs = volume of septic effluent introduced beneath the subdivision
Cs = concentration of NO3- as N contained in the septic effluent
Vp = volume of groundwater pumped by wells beneath the subdivision
Cp = concentration of nitrate-nitrogen contained in the pumped groundwater
This analysis estimates the average nitrate concentration of groundwater following acceptance of
septic system leachate and subdivision precipitation recharge. The nitrate concentration of the
septic system effluent is diluted by infiltrating precipitation and groundwater flow beneath the
proposed subdivision to produce a lower nitrate concentration at the subdivision boundary.
Vb is calculated using a hydraulic conductivity of 39.2 ft/day (294 gpd/ft2) (estimated above), an
aquifer width measured as the cross-section perpendicular to east-to-west groundwater flow
(2,000 ft.), an effective aquifer thickness of 60 ft. (saturated thickness in Section 2.4.2), and an
aquifer gradient of 0.018 ft/ft. Thus, Vb is:
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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Vb = 294 gpd/ft2 x 2,000 ft x 60 ft x 0.018 = 635,040 gpd
A value for ambient nitrate concentration (Cb) is taken from the sample presented in
Appendix A, from the Allred Well, i.e. 0.27 mg/L.
Precipitation also dilutes the concentration of nitrate from the septic system effluent.
Precipitation input is estimated as the infiltration rate (ft/day) of precipitation multiplied by the
subdivision area (ft2). The proposed subdivision is approximately 129 acres, or 5,612,000 ft2.
The mean annual precipitation is 23.57 inches. The percentage of total precipitation that reaches
the aquifer varies widely, as a function of precipitation patterns (both spatial and temporal), the
characteristics of the surface, competition from vegetation, evaporation, and runoff, etc.
Estimates commonly fall in the 5 - 10% range. Assuming a generic 5% of precipitation infiltrates
the aquifer to be conservative, Vi is:
Vi = (0.05 x 23.57 in / 12 in / 365 days) x 5,612,000 ft2 x 7.48 gal/ft3 = 11,295 gpd
The concentration of nitrate in the precipitation infiltrating the aquifer, Ci, is assumed to be
0.05 mg/L (WDEQ Chapter 23 default worksheet value).
The volume of septic effluent introduced beneath the subdivision, Vs, is the product of the
effluent recharge per lot and the number of lots. The effluent recharge is calculated as
300 gpd/unit (WDEQ Chapter 23 default value for three-bedroom homes) x 25 lots =
7,500 gpd.
For this analysis, the nitrate concentration of the septic system effluent, Cs, is assumed to be 40
mg/L (WDEQ Chapter 23 default value for conventional septic systems).
The daily volume of groundwater pumped by wells beneath the subdivision is calculated in Table
4 and we assume landscape water will be provided from the domestic-supply wells. Vp = 22,500
gpd at the ambient nitrate concentration of Cp = 0.27 mg/L.
Thus, the estimated groundwater nitrate concentration leaving the subdivision area at the down-
gradient property boundary estimated by this method is:
Co = (635,040 gpd x 0.27 mg/L + 11,295 gpd x 0.05 mg/L + 7,500 gpd x 40 mg/L –
22,500 gpd x 0.27 mg/L) / (635,040 gpd + 11,295 gpd + 7,500 gpd – 22,500 gpd) = 0.74 mg/L
Sensitivity Analysis. The calculated nitrate concentration is obviously sensitive to the accuracy
of the input parameters. While we have developed our estimates based on the available
information, as detailed above, many of the relevant parameters are only approximately known
for this site. The following sensitivity analysis indicates that the conclusion that the diluted
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
14
nitrate concentration will be less than the 10 mg/L limit at the down-gradient boundary is
robust.
The nitrate balance is dominated by the calculated groundwater flux through the alluvial aquifer.
The least well-constrained parameter in that calculation is the permeability of the portion of the
aquifer into which septic system effluent will be introduced. Application of a 50% lower
hydraulic conductivity value (147 gpd/ft2) increases the calculated Co to 1.21 mg/L.
The percentage of precipitation that infiltrates to recharge groundwater is rarely well
constrained. Increasing that percentage to 10% (all other parameters as in the base case)
produces a small net effect, i.e. a calculated Co value of 0.73 mg/L.
Appendix B calculations. The calculations presented in WDEQ Chapter 23, Appendix B provide
an estimate of vertical travel time from a leach field to the water table, and the distance leachate
arriving at the groundwater table will travel horizontally over any remaining time within a total
time period of two years.
The Appendix B analysis uses the following equation to calculate vertical travel time:
t1 =d *
.*
q
a05
where, t1 = vertical travel time in years,
d = depth to groundwater in cm,
θ = volumetric soil moisture
α = total recharge (effluent + precipitation in cm/yr)
The average depth to groundwater from Table 1, discussed above, is 83 feet (2,530 cm).
The moisture content of the unsaturated zone (θ) is assumed to be 0.321 mL/cm3 from Chapter
23, Appendix B, for “sandy clay”, the default value, the description for which is reasonably
consistent with the driller logs of the alluvial deposits (see attached Statements of Completion in
Appendix C).
The required soil absorption infiltration area is 696 ft2, as presented in Table 3 for a 3-bedroom
house.
The total annual effluent discharge per individual system is estimated as:
3 bedrooms x 100 gpd/bedroom x 365 days/year x 1 ft3/7.48 gal = 14,600 ft3
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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Across the area of the individual leach field, the effluent recharge to the aquifer in inches per
year is thus:
14,600 ft3 / 696 ft2 x 12 = 252 inches
To calculate total flux into the aquifer through the leach field footprint, 5% of the average
annual precipitation is added to the effluent volume. The average annual precipitation is
23.57 inches (discussed above). Thus, α, the total annual recharge to the aquifer is
253 inches/year (252 in. + .05*23.75 in.), or 643 cm/year.
The average estimated vertical travel time to the water table is thus:
t1 = 2,530 cm x 0.321 mL/cm3 / (0.5 x 643 cm/year) = 2.53 years
Because the vertical travel time is greater than two years, the horizontal distance that the leachate
will migrate need not be calculated, nor is the location of individual septic system leach fields
within the footprint of the subdivision relevant.
Sensitivity Analysis. As the ground surface slopes downward to the west, the depth to
groundwater decreases. Thus, the above calculation based on average conditions may
overestimate the vertical travel time for the western portion of the subdivision. To prevent
outliers, the median depth to water (80 feet) was input into the calculation for this sensitivity
analysis. At a depth to water of 80 feet the vertical travel time estimated by this method is
2.43 years.
Appendix C calculations. WDEQ Chapter 23 Appendix C calculations are provided to assess
potential impacts to public drinking water supply wells. Based on data from the U.S.
Environmental Protection Agency (EPA) Drinking Water Watch website, there are no public
water supply wells completed in the alluvial aquifer within 1.5 miles or downgradient of the
proposed subdivision. Thus, Appendix C calculations are not required.
3.8 Wastewater Conclusions and Recommendations
The proposed Lost Creek Meadows Subdivision consists of 25 single-family residential lots. The
lots will have a minimum acreage of approximately 4.77 acres, and will average 5.13 acres each.
Each lot will utilize an on-lot wastewater system (standard septic system and leach field) and
individual on-lot wells. The Lincoln County regulations for minimum lot size will be met. Also,
there will be adequate building space available at each site for construction of a leach field and
replacement leach field while still meeting the required separation distances and slope
requirements.
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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The soils in this subdivision have percolation rates that suggest wastewater will receive adequate
treatment and will not create surfacing problems. It is not anticipated that shallow impermeable
layers or groundwater depth will cause any problems with individual on-site wastewater systems.
The topography is generally flat.
The cumulative nitrate loading analysis indicated that the impact due to the subdivision will be
under the threshold set by WDEQ. Use of individual on-lot standard septic systems will be
allowed. No off-site public water wells are located where there is any potential for contamination
from the proposed subdivision. Effluent generally will not travel beyond lot lines within a two-
year travel time.
Risk of groundwater contamination appears to be low due to the low density of the
development and soils that will allow for adequate treatment of the wastewater with adequate
setbacks. The groundwater flux through the alluvial aquifer will extensively dilute any impact
from the wastewater systems. The geology of the area and characteristics of the aquifer indicate
that use of individual on-lot wastewater systems would be appropriate.
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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4.0 ON-LOT WATER WELL ADEQUACY
4.1 Water Quantity
The Lost Creek Meadows Subdivision will have a build-out of 25 lots for single-family
residential use. Water demands for the subdivision will be served by individual on-lot wells with
design flows of 10 gpm or 900 gpd per lot. Details for estimated water usage are found in
Table 4.
Table 4. On-Lot Water Requirements
Lot #’s Type Water System Average Day
Use (gpd)
Peak Day
Use (gpd)
1 - 25 Single-Family
Residential
Individual On-Lot
Wells
22,500 61,200
There are no existing wells located within the proposed subdivision area. However, as listed in
Table 1 and compiled in Appendix E, domestic-supply wells in the immediate area are
commonly permitted for flows in excess of 10 gpm. Reported yields for the Table 1 wells less
than 200 feet deep (i.e. presumably completed in the alluvial aquifer) average 17 gpm. The
highest reported yield is 25 gpm. (The peak-day demand per lot listed in Table 4 is
approximately 1.7 gpm.)
4.2 Water Quality
Owner-reported assessments of the water quality from the aquifer available to host individual
domestic wells for the proposed subdivision are uniformly “good” (which is the highest ranking
available on the reporting form). Specific water quality data are provided for a 2022 sample from
the nearby Allred Well in Appendix A. Both the laboratory analysis and the widespread use of
the alluvial aquifer for area drinking water demonstrate its suitability.
Potential sources of contamination of the aquifer consist of on-site septic systems and the
inherent exposure to surface application and accidental release of the various chemicals
associated with residential living. In addition, the area is in the midst of agricultural lands,
exposing the shallow aquifer to recharge potentially including agricultural chemicals. The
potential impact of local wastewater disposal facilities with respect to nitrate concentrations is
evaluated in Section 3.0.
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
18
4.3 Water System Conclusions and Recommendations
The proposed Lost Creek Meadows Subdivision consists of 25 lots, with an average lot size of
5.13 acres and a minimum lot size of roughly 4.77 acres. Single-family residential lots will utilize
individual on-lot wells. Lincoln County regulations for minimum lot size for subdivisions will be
met.
Water quality testing indicates that the water is safe for domestic purposes. Data from area wells
indicate that adequate water will likely be available from the on-site wells. The results of this
study indicate that the use of individual on-lot wells to serve the Lost Creek Meadows
Subdivision is appropriate.
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
19
5.0 REFERENCES
Driscoll, F.G., 1986. Groundwater and Wells, Second Edition, p 1021. Empirical equations used
to estimate specific capacity and transmissivity.
Forsgren Associates & Weston Engineering 2009. Star Valley Ranch Groundwater Level II
Study; consultant report for Wyoming Water Development Commission.
Johnson, I. A., 1967. Specific Yield – Compilation of Specific Yields for Various Materials. U.S.
Geological Survey Water Supply Paper 1662-D.
Larsen, M.C., LaForge, J.S., and Wittke, S.J., 2015, Surficial geologic map of the Afton 30' x 60'
quadrangle, Sublette and Lincoln counties, Wyoming: Wyoming State Geological Survey
Open File Report 15-9, scale 1:100,000.
Lincoln County, Wyoming. 2019 Revision. Land Use Regulations, Chapter 6, Development
Standards.
Lincoln County Office of Planning and Development, 1986, Lincoln County Regulations for a
Permit to Construct, Install, or Modify Small Wastewater Facilities and Related Design
Standards, 36 pp.
Miller, Cheryl A., Maria Plafcan, and Melanie L. Clark. 1996. Water Resources of Lincoln
County, Wyoming; U.S. Geological Survey Water-Resources Investigations Report 96-
4246.
Natural Resources Conservation Service, U.S. Department of Agriculture. Web Soil Survey.
<http://websoilsurvey.nrcs.usda.gov/>.
Soil Conservation Service, U.S. Department of Agriculture. March 1976. Soil Survey of Star
Valley Area, Wyoming-Idaho.
Sterrett, Robert. 2007. Groundwater & Wells; Johnson Screens, third edition, p. 19 (approximate
average value from Table 2.1 for “sand & gravel mix”).
U.S. Environmental Protection Agency. 2022. Drinking Water Watch, Public Water Supply
Systems Search. EPA Region 8. <
https://sdwisr8.epa.gov/Region8DWWPUB/index.jsp>
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
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U.S. Geological Survey. 2015. USGS 7.5 Minute Series Topographic Quadrangle Map for Etna,
Wyoming-Idaho.
Wyoming Department of Environmental Quality. July 2012. Water Quality Rules and
Regulations Chapter 23.
Wyoming Department of Environmental Quality. July 2012. Water Quality Rules and
Regulations Chapter 25.
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
FIGURES
www.sunrise-eng.com
AFTON, WYOMING 83110
47 EAST 4TH AVENUE
TEL 307.885.8500 Z FAX 307.885.8501
ENGINEERING
ORTHN
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
APPENDIX A
Water Quality Data
LABORATORY ANALYTICAL REPORT
Client:Sunrise Engineering Inc
Project:Self Subdivision
Lab ID:C22010603-001
Client Sample ID:Allred Well
Collection Date:01/18/22 10:30
Matrix:Drinking Water
Report Date:02/23/22
DateReceived:01/19/22
Prepared by Casper, WY Branch
Analyses Result Units Analysis Date / ByRLMethod
MCL/
QCLQualifiers
MAJOR IONS
01/22/22 02:47 / dmb1mg/LNDChloride E300.0
01/21/22 16:36 / kjp0.1mg/LNDFluoride A4500-F C
01/22/22 02:47 / dmb1mg/L4Sulfate E300.0
PHYSICAL PROPERTIES
H 01/20/22 11:58 / mnm0.1s.u.7.9pH A4500-H B
01/20/22 11:58 / mnm°C15.6pH Measurement Temp A4500-H B
01/20/22 13:16 / mnm20mg/L180Solids, Total Dissolved TDS @ 180 C A2540 C
NUTRIENTS
01/20/22 13:20 / nts0.05mg/L0.27Nitrogen, Nitrate+Nitrite as N E353.210
METALS, TOTAL
02/01/22 05:00 / jcg0.001mg/LNDAntimony E200.80.006
02/02/22 06:21 / jcg0.005mg/LNDArsenic E200.80.01
02/02/22 06:21 / jcg0.05mg/LNDBarium E200.82
02/01/22 05:00 / jcg0.001mg/LNDBeryllium E200.80.004
02/01/22 05:00 / jcg0.001mg/LNDCadmium E200.80.005
01/25/22 22:17 / srm1mg/L47Calcium E200.7
02/02/22 06:21 / jcg0.005mg/LNDChromium E200.80.1
02/01/22 05:00 / jcg0.01mg/LNDCopper E200.81.3
D 02/04/22 17:35 / srm0.05mg/L0.34Iron E200.7
02/02/22 06:21 / jcg0.001mg/LNDLead E200.80.015
01/25/22 22:17 / srm1mg/L18Magnesium E200.7
D 02/01/22 05:00 / jcg0.003mg/L0.005Manganese E200.8
01/26/22 13:00 / eli-b0.0001mg/LNDMercury E245.10.002
02/01/22 05:00 / jcg0.01mg/LNDNickel E200.8
D 02/02/22 06:21 / jcg0.002mg/LNDSelenium E200.80.05
02/04/22 17:35 / srm1mg/LNDSodium E200.7
02/17/22 19:13 / jcg0.0005mg/LNDThallium E200.80.002
02/01/22 05:00 / jcg0.01mg/LNDZinc E200.8
RADIONUCLIDES, TOTAL
U 02/03/22 02:33 / hatpCi/L-0.4Gross Alpha E900.0
02/03/22 02:33 / hatpCi/L1.9Gross Alpha precision (±)E900.0
02/03/22 02:33 / hatpCi/L2.0Gross Alpha MDC E900.0
U 02/18/22 15:02 / dmfpCi/L-0.4Gross Alpha - Adjusted E900.015
02/18/22 15:02 / dmfpCi/L1.9Gross Alpha - Adjusted precision (±)E900.0
02/18/22 15:02 / dmfpCi/L2.0Gross Alpha - Adjusted MDC E900.0
Report
Definitions:
RL - Analyte Reporting Limit MCL - Maximum Contaminant Level
QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)
D - Reporting Limit (RL) increased due to sample matrix H - Analysis performed past the method holding time
U - Not detected at Minimum Detectable Concentration
(MDC)
Page 3 of 17
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
APPENDIX B
Percolation Test Data
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
APPENDIX C
Well Statements of Completion
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
APPENDIX D
Water Rights Data
SUNRISE ENGINEERING • LOST CREEK MEADOWS SUBDIVISION WATER & WW SYSTEM ADEQUACY STUDY
APPENDIX E
Well Permits Within One Mile
P. O. Box 1162 Afton, WY 83110
June 14, 2023
The Office of Planning and Development Attention Kemmerer Office 925 Sage Ave. Suite 201 Kemmerer, WY 83101 SUBJECT: LOST CREEK MEADOWS DEVELOPMENT
Dear Members of the Office of Planning and Development
Star Valley has been my home for over 40 years. I live in Afton but spend a great
deal of time with friends living in the Lost Creek area. Over the years I have hiked
the trails in the area almost every day during the summer months, helped move irrigation pipes during the fall months and for over two decades cross country skied with my Lost Creek friends. Without doubt Lost Creek is a very special place! There are many legitimate concerns dealing with the development of the LDS
Church Farm Land that is now called the “Meadows Development”.
1. Septic Tank Issues Placing the Drinking Water at Risk
Teton County Example: Flat Creek and Fish Creek—impaired due to excessive and unsafe concentrations of E. coli, harmful bacteria found in domestic waste water. The residents of Hoback Junction had to investigate the cause of their ground water contamination. There have also been serious problems at other Teton County locations as well.
Over the past three years, Teton County has spent thousands and thousands of dollars dealing with ground water vs. septic systems.
Residents have been harmed. Why does Lincoln County have to
duplicate Teton County’s mistakes?
2. Lost Creek Water District Lost Creek residents have been dealing with water issues for several years. Adding more and more homes to the system isn’t helping. Once again the residents of Lost Creek and Lincoln County will be dealing with this issue in
the future.
3. Lost Creek Road
The road is dangerous for it is not designed to handle a lot of traffic and as a result the drive can be stressful, especially during the winter months. Increasing the number of vehicles (not to mention joggers, bike riders walkers and school buses) using this road will only make it more dangerous. Once again Lincoln County will be dealing with this issue in the future. 4. Has There Already Been an Agreement?
Dump trucks were observed most of last summer hauling dirt and gravel to
the Meadows Development. The cost to developers had to be exorbitant.
Why would a developer spend that kind of money unless they had some kind of reassurance to do so? Star Valley is a special place. Lost Creek is a special place. Surely there is a solution for a development that plans to build too many houses—instead there should be fewer homes, fewer septic tanks, fewer water wells, fewer homes
hooking up to the Lost Creek Water District and fewer vehicles using the road.
Most of all protect the residents of Lost Creek. Protect Lincoln County Tax
Payers from having to pay for mistakes that should have never happened, while the
developers make a fortune. Sincerely
Kent Eberspacher
Reference is made to the proposed Lost Creek Meadows Subdivision
Being a long time resident of the lost Creek area (53 years) I have witnessed the effects of residential development in Star Valley and on lands in the vicinity of the Lost Creek Meadows proposal. It goes without saying that people are moving to Star Valley to enjoy the many life
style benefits the area has to offer. Sadly, the qualities that people are moving here to enjoy are rapidly diminishing with population expansion and associated impacts to resources and infrastructure (roads, utilities, etc.). Proposed developments such as the Lost Creek meadows proposal greatly exacerbate the problems. At this point, little is known how the project proponent plans to mitigate obvious impacts to the existing infrastructure such as water, sewer, roads, utilities, etc., so it is difficult to provide any meaningful comment except to one precious commodity - water! All developments approved in the Star Valley area to date seem to have one common denominator: There apparently will be no long term irreversible and irretrievable impacts to the water and soil resources! This is patently not true! Wells within the valley are showing signs of contamination from both industrial
(North Lincoln Land Fill) and commercial development! Unlike roads which can be repaired or power utilities that can be expanded or replaced, damaging impacts to the water and soil resources are virtually permanent in our life time.
Star Valley is not a huge land mass that can absorb land use impacts forever. Space is limited and any impacts are, in my opinion, significant. With these thoughts in mind, I feel it is the duty
and responsibility of Lincoln County to bring a halt to this somewhat rampant development and complete a detailed environmental analysis of impacts that are occurring in the valley and prepare a coherent land use plan that addresses these obvious impacts!
6/9/23, 1:08 PM LINCOLN COUNTY WYOMING Mail - Lost Creek Subdivision
https://mail.google.com/mail/u/0/?ik=f1e3f38f9b&view=pt&search=all&permthid=thread-f:1767705278571716443&simpl=msg-f:1767705278571716443 1/1
Robert Davis <robert.davis@lincolncountywy.gov>
Lost Creek Subdivision
1 message
Rick Johnson <ricklj@silverstar.com>Sat, Jun 3, 2023 at 11:58 AM
To: planning@lincolncountywy.gov
We are concerned about the impact that 25 new domestic wells and 25 new leach fields will have on our existing
domestic water supply. Have any studies been done? I assume that the ground water flows directly from the
development to our property. We are located southwest of the proposed development. We would be in favor of studies
being done BEFORE the subdivision application is approved. Thanks!
Fredrick and Megan Johnson
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6/9/23, 1:07 PM LINCOLN COUNTY WYOMING Mail - Lost Creek Meadows Comments
https://mail.google.com/mail/u/0/?ik=f1e3f38f9b&view=pt&search=all&permthid=thread-f:1767780779856345236&simpl=msg-f:1767780779856345236 1/1
Robert Davis <robert.davis@lincolncountywy.gov>
Lost Creek Meadows Comments
1 message
robert gonet <gonetr7@gmail.com>Sun, Jun 4, 2023 at 7:58 AM
To: planning@lincolncountywy.gov
I have comments and questions on the proposed Lost Creek Meadows Subdivision. I am assuming that these
comments will be considered and presented to the commissioners for action prior to any approvals for the subdivision.
The developer released a preliminary platt showing two roads leading to cul de sacs, yet has built roads and
infrastructure for a loop connecting to Ross Road in two places. Had there been any consideration or approvals based on
the first release of the platt that would not have been issued for the as built infrastructure? If so, what were they?
What questions and considerations have, or will be, addressed concerning increased traffic on Lost Creek and
Muddy String roads? The addition of twenty-five housing units using both Lost Creek and Muddy String Roads raises
safety concerns for those living along those roads, especially Muddy string road which is already experiencing heavy
summer and winter increased traffic, with an unenforced 45 mph speed limit.
What will the effect be on the Lost Creek drainage by adding surface run off from infrastructure and potential
drainage of twenty five new septic systems? How will the developer deal with mandated set backs from the stream?
How will culinary water be supplied to the twenty-five new structures? If by wells, what protections will be provided
to those having older water well rights, if the development negatively impacts their wells? If the development is to
become part of the Bedford Sewer and Water, how will hook up be accomplished.
Has there been a surface and subsurface water study to examine the real or potential impacts on those resources?
Who will ultimately sign off on those considerations?
Has the developer submitted an acceptable plan to the Lost Creek Irrigation Company for distribution of irrigation
water and have they contacted the canals transecting the proposed development with any sort of plan?
Please acknowledge receipt of these comments.
Robert Gonet
Bedford