Staff Report re Appeal of MDNS Conditions~ ~,~~ Tip Sta f f Report c~<.~.
City of Yelm
ELM Community Development Department ~`
W4SNINOTON l
To: Stephen K. Causseaux, Jr., Hearing Examiner l~,
From: Grant Beck, Director of Community Development (~. ~ 6
Date: October 17, 2005 L~'
Subject: Appeal of Mitigated Determination of Non-Significance BSP-05-0197-YL
Appellant: 3B&C, LLC
Location: 10336 West Road SE, Yelm, WA.
Proposal: Appeal Mitigation Measure 3(a, b, c, & d) of the MDNS issued for the
proposed West Road Professional Park.
I. INTRODUCTION
Erling Birkland, 36&C LLC appeals mitigation measures attached to a Mitigated
Determination of Non-significance for a proposed binding site plan to create commercial
spaces for and site plan review to construct a 5,600 square foot commercial building.
II. BACKGROUND
3B&C LLC has applied for a binding site plan and site plan review to create a
professional business park on West Road in the City of Yelm.
The City of Yelm reviewed the SEPA checklist and issued an MDNS on August 12,
2005. The MDNS included the following mitigating measures being appealed:
3. Civil plan submission shall include an updated preliminary stormwater plan
that meets or exceeds the standards in the 1992 stormwater Manual as
adopted by the City of Yelm. The stormwater plan shall include the
following elements:
a. Alternative technologies are not accepted.
b. The elevation of the bottom of the infiltration gallery shall be a
minimum of six feet above the elevation of the high groundwater
area as identified by Thurston County (approximate elevation 335),
and must be 50 feet horizontally, or 2 feet vertically away from the
High Ground water area; which ever distance is less.
c. Separate water quality treatment for roof runoff shall be provided.
d. The stormwater system shall be designed to accommodate
stormwater generated by required frontage improvements.
III. ISSUES
The applicant appealed the City's issuance of the Mitigated Determination, specifically.
conditions relating to the use of emerging stormwater treatment technologies and the
requirementthat the bottom of the infiltration gallery be no less than 6 feet above the
high groundwater area.
The basis for the appeal is that some of the conditions of the MDNS were not disclosed
during the pre-submission meeting, that the Salmon Creek Standards have not been
adopted by the City of Yelm, that that the proposed stormwater system design meets
the 1992 stormwater Manual, and that the City has approved emerging stormwater
treatment technologies in the past.
IV. ANALYSIS
The Yelm Municipal Code does not contemplate that the pre-submission review
requires the City to identify all standards, provisions, and policies which will
apply to the proposed plan.
The Hearing Examiner previously found as part of the Rothwell appeal of the approval
of a site plan review application (APL-03-8361-YL) that pre-submission notes are not
binding. To reinforce this concept, it is the unbroken practice of the Community
Development Department place at the top of all pre-submission comments the following
language:
These comments are preliminary in nature and are not intended to
represent final comments and or requirements for the City of Yelm.
Until a complete application is made, the Community Development
Department can only attempt to inform the applicant of general
requirements as they appear in the form presented by the applicant
at the time of pre-submission.
This note was included on both the Planning and Civil Engineering notes for the
proposed business park.
The State Environmental Policy Act does not limit the Responsible Official to
adopted codes and regulations to mitigate potential environmental impacts.
The appellant notes that the 1992 stormwater manual only requires three feet of vertical
separation between the bottom of a infiltration gallery and groundwater and that the City
has not adopted the Interim Site Development Standards for New Development in
Salmon Creek Basin.
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As noted in the findings of the MDNS, however, the City identified that the proposed
development is located in a critical aquifer recharge area and adjacent to a potential
high groundwater flooding area. If, during a high groundwater event, the groundwater
elevation is higher than the required three feet of vertical separation as required by the
1992 stormwater Manual, the strong possibility exists of untreated stormwater entering
the groundwater, which is also a critical aquifer recharge area.
In order to mitigate this potential significant impact, the City looked to the standards in
the Interim Site Development Standards for New Development in Salmon Creek Basin,
adopted by Thurston County after high groundwater events in the mid 1990's. Adjacent
to an area of known high groundwater, this document establishes a screening threshold
for all development of 6 feet to known high groundwater. If the bottom of the infiltration
gallery is less than 6 feet above groundwater, over winter monitoring and additional
engineering analysis is required. If the bottom of the infiltration gallery is greater than 6
feet above groundwater, no other special standard need be met in order to protect the
aquifer.
In this instance, as with the updated Yelm Critical Areas Code, which was adopted by
the City Council on September 28, 2005, the City chose to require the 6 feet of
separation rather than having the project go through a years worth of ground water
monitoring before designing the stormwater system.
These conditions are reasonable and are designed to appropriately mitigate identified
probable significant impacts to the environment.
Allowing the use of emerging stormwater treatment technologies is discretionary
on the part of the City and is not always appropriate.
The appellant wishes to utilize a vortechs system by Stormwater360, Inc. as part of the
stormwater quality treatment component at the site. As noted in the appeal, the City
has rarely allowed an emerging stormwater treatment technology system to be used
within the City. Also as noted in the appeal, one of the few entities that the City has
allowed to utilize these technologies is Yelm Community Schools.
The City approved the use of emerging technologies for the School District because the
District has the maintenance staff and financial resources to maintain the system and
complete status reports on the operation of the system pursuant to the General Use
Designation issued by the Washington State Department of Ecology for the vortechs
system.
A small development such as the proposed business park, where the stormwater
system is likely'to be owned and maintained by a condominium owners association, is
not the appropriate situation to test emerging stormwater technologies.
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Certain clarifications to fhe Mitigated Determination of Non-significance to
address questions raised by the appellant are appropriate.
Condition 3b indicates that the groundwater elevation is approximately 335 feet. This
elevation is approximate and was only cited in order to provide some indication. of the
groundwater elevation to the application.. The key requirement is that the bottom of the
infiltration gallery must be 6 feet above the high groundwater. The high groundwater
area will be established by the appellants surveyor, most likely through the use of the
high groundwater maps and aerial photographs of the high groundwater areas provided
by Thurston County.
Condition 3c requires separate water quality treatment for roof run-off. The intent of this
condition is to separate, the.roof run-off, which is assumed to be clean pursuant to the
1992 Stormwater Manual, be directed to a drywell and not through the stormwater
. system, in order to reduce the size of the stormwater system.
Condition 3d requires the development to accommodate storm drainage from frontage
improvements. There is no publicly owned stormwater system in the area of this
proposed development. The system the appellant refers to as being available to direct
stormwater from frontage improvements towards is a private system installed to
,accommodate stormwater treatment from that development:
VI. CONCLUSION
The Mitigated Determination of Non-significance should be upheld.
LIST OF EXHIBITS
Appeal Notice and Letter
Mitigated Determination of Non-significance
Hearing Examiner Decision - RothwelLAppeal
Pre-submission notes -Civil
Pre-submission notes -Planning
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