Summit Waller Community Association v. Pierce County ( 2019 )


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  •                                                                                           Filed
    Washington State
    Court of Appeals
    Division Two
    February 6, 2019
    IN THE COURT OF APPEALS OF THE STATE OF WASHINGTON
    DIVISION II
    SUMMIT-WALLER COMMUNITY                                         No. 50363-8-II
    ASSOCIATION, NORTH CLOVER
    CREEK/COLLINS COMMUNITY
    COUNCIL,
    Appellants,
    v.
    PIERCE COUNTY                                             UNPUBLISHED OPINION
    Respondent,
    and
    BETHEL SCHOOL DISTRICT, SUMNER
    SCHOOL DISTRICT, PENINSULA
    SCHOOL DISTRICT, EATONVILLE
    SCHOOL DISTRICT, and GRAHAM MC,
    LLC and APOGEE CAPITAL, LLC and
    HIGH VALLEY INVESTMENT, LLC and
    TACOMA SCHOOL DISTRICT,
    Respondents.
    JOHANSON, J. — Summit-Waller Community Association, North Clover Creek, and the
    Collins Community Council (collectively the “Communities”) appeal an order of the Central Puget
    Sound Region Growth Management Hearings Board (Board). The Board upheld Pierce County’s
    No. 50363-8-II
    approval of an area-wide map amendment M-2 to a land use designation map in the Pierce County
    Comprehensive Plan (Comprehensive Plan),1 which redesignated eight parcels of land within the
    County. The Communities argue that the Board erred as a matter of law that its order was
    unsupported by substantial evidence and that the Board’s decision was arbitrary and capricious.
    The Communities also contend that the Board erred when it concluded that their timeliness
    challenge to amendment M-2 was moot. Finally, the Communities raise some arguments here that
    they did not raise before the Board, thus we do not consider them. Finding no error, we affirm.
    FACTS
    The Communities challenge the redesignation of eight parcels of land2 located in an area
    covered by the Comprehensive Plan. The County redesignated the land use of the eight parcels
    from “Employment Center” (EC) to “High Density Residential” (HRD). Clerk’s Papers (CP) at
    12. The Pierce County Council (Council) approved the redesignation in amendment M-2 by
    passing Ordinance No. 2015-40.
    Amendment M-2 allowed an HRD land use designation for the eight parcels, which in turn
    allowed “multifamily and high density single-family and two-family housing” development with
    up to “25 dwelling units per acre.” Administrative Record (AR) at 1894, 1892. An HRD land use
    designation allows for “limited neighborhood commercial retail and service uses.” AR at 1892.
    1
    Amendment M-2 was an amendment to the Mid-County Community Plan, which is part of the
    Comprehensive Plan. A community plan is a local development plan that adds to, but cannot
    conflict with, “the Countywide Comprehensive Plan.” For ease of reference, we describe
    amendment M-2 as an amendment to the Comprehensive Plan, rather than as an amendment to the
    Mid-County Community Plan.
    2
    The eight parcels cover approximately 34 acres in Pierce County between Tacoma and Puyallup.
    The parcels are within an Urban Growth Area (UGA) boundary.
    2
    No. 50363-8-II
    Before the amendment, the eight parcels consisted of mostly vacant property. The Communities
    were located in a rural separator land use designated area south of the eight parcels.
    I. 2014 AMENDMENTS TO THE PIERCE COUNTY CODE (PCC)
    In 2014, the Council amended chapter 19C.10 PCC, titled “Procedures for Amendments to
    the Comprehensive Plan.” AR at 1675. The Council adopted former PCC 19C.10.050(F) (2014),
    which provided that applications for amendments to the Comprehensive Plan proposed as part of
    the periodic update under GMA provision RCW 36.70A.130(5)(a) “shall not be subject to the
    application requirements of [former PCC] 19C.10.050 E [(2014)] or [former PCC] 19C.10.055
    [(2009)] but shall include an analysis and recommendation pursuant to [former] PCC 19C.10.065
    [(2014)].” AR at 1678. As part of the amendment to chapter 19C.10 PCC, the Council adopted
    former PCC 19C.10.065(A), which provided that
    [d]uring a required [Growth Management Act (GMA), ch. 36.70A RCW,] periodic
    update, the Planning and Land Services [(PALS)] Department shall evaluate
    Council-Initiated amendments based upon [a list of factors].
    CP at 214. The amendments to chapter 19C.10 PCC were approved in Ordinance 2014-31s, which
    became effective on July 1.
    II. AMENDMENT M-2 TO THE COMPREHENSIVE PLAN
    A. APPLICATION FOR AMENDMENT M-2
    On July 30, Scott Edwards, the managing member of Apogee Capital LLC and High Valley
    Investment LLC (collectively “Intervenors”), filed an application for amendment M-2.
    Amendment M-2 was an area-wide map amendment, which the County defined as “a proposed
    change or revision to the Comprehensive Plan Generalized Land Use Map.” Former PCC
    19C.10.030(A) (2005). “An Area-Wide Map amendment, unlike a parcel or site-specific land use
    3
    No. 50363-8-II
    reclassification proposal, is of area-wide significance and includes many separate properties under
    various ownerships.” Former PCC 19C.10.030(A).
    As proposed in the application, amendment M-2 sought to amend the land use designation
    and zone classification for the eight parcels at issue. The application suggested that the Council
    approve an “Urban Center”3 land use designation with an implementing “Community Center”
    (CC) zone classification. CP at 155. A CC land use designation “has as its focus a significant
    traffic generator around which develops a concentration of other commercial office, services, and
    some high-density residential development.” AR at 1892.
    At the time of the application, the eight parcels had an EC land use designation with an
    implementing Community Employment (CE) zone classification.
    B. RESOLUTION R2014-94S
    In September, the Council initiated a number of proposed amendments to the
    Comprehensive Plan as part of the “continuing review and evaluation” required under GMA
    provision RCW 36.70A.130. CP at 147. One such Council-initiated amendment was amendment
    M-2.4 In Resolution No. R2014-94s, the resolution initiating amendment M-2, the Council
    directed PALS to “evaluate Council initiated amendments pursuant to [former PCC] 19C.10.065.”
    CP at 148. The Council also noted that “all applications received for Council initiation by July 31,
    3
    There was no Urban Center land use designation at the time, but there was an Urban Center
    zoning category in the Zone Classifications Table, which included a CC zone classification.
    Former PCC 18A.27.010 (2014).
    4
    The Council initially referred to amendment M-2 as Map Amendment PA-21.
    4
    No. 50363-8-II
    2014, were reviewed against the acceptance criteria adopted in [former PCC] 19C.10.050[(F)]”
    and that “applications that did not meet the criteria were removed from consideration.” CP at 148.
    C. PALS INITIAL STAFF REPORT
    PALS submitted a staff report to the Pierce County Planning Commission (Planning
    Commission) analyzing amendment M-2 based on the criteria enumerated under former PCC
    19C.10.065(A). PALS (1) answered “[u]ndetermined” in response to whether there was “a
    community or countywide need” for amendment M-2 and whether the amendment would “provide
    public benefits”; (2) noted that there was infrastructure available and summarized the nearby
    sewers, water utilities, roads, schools, and fire district; (3) noted a physical constraint on the eight
    parcels that “development regulations address[ed]”; (4) noted an environmental constraint that
    “could generate noise impacts to adjacent properties”; (5) listed the land uses and activities on the
    eight parcels; (6) listed the land uses and activities on neighboring properties; and (7) concluded
    that amendment M-2 was “not consistent with the policies in the Comprehensive Plan for
    expanding an existing area designated as [CC].” CP at 130-31.
    PALS also concluded that the eight parcels “may have been inappropriately [re]designated
    as EC” from a Mixed Use District in 2006, because the land did “not meet [Comprehensive Plan]
    policies for locating [EC] designations.” CP at 130. Instead, PALS “question[ed] whether a higher
    density residential designation may be more appropriate as a transition into the surrounding
    neighborhood.” CP at 130 (emphasis added). PALS’ staff report indicates it recommended that
    the County address the “area as part of the more extensive 2015 Comprehensive Plan update.” CP
    at 130.
    5
    No. 50363-8-II
    D. MID-COUNTY LAND USE ADVISORY COMMISSION MEETING
    The Mid-County Land Use Advisory Commission (MCAC) considered amendment M-2
    at a public meeting on November 4. At the meeting, MCAC noted that the eight parcels “may
    have been inappropriately designated as EC” because they did “not meet the standards for a
    concentration of commercial uses” or “criteria for [an EC].” CP at 144. Because the proposed CC
    designation and the existing EC designation were inappropriate, “staff was open to consideration
    of an alternate designation” for the eight parcels. CP at 144.
    During public testimony on amendment M-2, Brynn Brady spoke as representative of the
    Intervenors and indicated that a land use designation permitting “multi-family development”
    would be satisfactory. CP at 144. Brady also noted that the Intervenors had vested applications
    for multi-family development that expired due to inactivity during the recession.
    MCAC passed a motion to support PALS’ recommendation discussed above.
    E. PLANNING COMMISSION MEETING
    The Planning Commission considered amendment M-2 at a public meeting on December
    4. The Planning Commission noted that the eight parcels did “not meet criteria for [a CC]” and
    did “not meet [the criteria for an EC] designation.” CP at 168.
    The Planning Commission noted that PALS would work with MCAC “as part of the
    Comprehensive Plan update if they want to see [the eight parcels] redesignated to a different [land
    use] designation more appropriate for the site, such as [HRD] . . . implemented with a[] Moderate
    High Density Residential (MHR) [zone] classification.” CP at 168. The Planning Commission
    noted that the addition of an HRD land use designation and implementing MHR zone classification
    6
    No. 50363-8-II
    “was vetted with [the] Economic Development Department[,] which agreed that [the eight parcels]
    may not be appropriately designated” as an EC. CP at 168.
    One of the planning commissioners asked if the “additional property owners were notified
    of the public meeting” and “staff” responded “yes”.           CP at 169.   However, the Planning
    Commission noted that neighboring property owners were notified of amendment M-2 as proposed
    in the application, but not that the proposal could change.
    The agenda for the meeting noted that the Planning Commission would hear testimony on
    amendment M-2. The agenda also noted that the County would post staff reports detailing
    “individual proposed amendments” on its website. AR at 1699.
    The Planning Commission approved a motion to have PALS “prepare an alternative
    recommendation to accommodate high density residential development.” CP at 169.
    F. PALS’ MODIFIED RECOMMENDATION
    PALS noted that it “reviewed [additional] information and modified its recommendation
    for [amendment] M-2” in errata to its initial staff report. CP at 172. PALS recommended
    redesignation from an EC to an HRD land use designation, along with an implementing MHR
    zoning classification, “as it would be more appropriate as a transition into the surrounding
    neighborhood.” CP at 173.
    PALS also recommended text amendments to the Comprehensive Plan adding the HRD
    designation and MHR zone. The text amendments explained that the proposed HRD designation
    was “intended to be composed of multi-family and high density single-family and two-family
    housing and limited neighborhood retail and service commercial uses” and that the proposed
    7
    No. 50363-8-II
    “MHR zone differ[ed] from Pierce County’s current HRD zone in that it d[id] not allow for
    commercial uses.” CP at 173.
    G. PLANNING COMMISSION HEARINGS
    The Communities participated in a public hearing before the Planning Commission on
    April 21, 2015, through their representative, Dan Haire. Haire asked the Planning Commission to
    reconsider its recommendation that the Council should adopt amendment M-2 with an HRD
    redesignation of the eight parcels. The meeting minutes do not reflect any argument by Haire that
    the County denied him the required public notice of the proposed redesignation from an EC to an
    HRD in amendment M-2.
    The Planning Commission held several other public meetings on the periodic review of the
    Comprehensive Plan, of which amendment M-2 was a part.              Although members of the
    Communities appeared at some of these meetings, there is no indication that the Planning
    Commission specifically addressed amendment M-2 at those meetings.
    H. COMMUNITIES’ LETTERS
    On April 28 and June 2, the Communities sent letters to the Planning Commission and the
    Council arguing that PALS failed to properly evaluate the criteria under former PCC
    19C.10.065(A) in considering amendment M-2 and failed to adhere to the “no net loss policy” for
    ECs. AR at 65. The Communities did not argue that the County failed to provide them notice of
    amendment M-2 or denied them an opportunity to participate in the County’s consideration of
    amendment M-2. In the letters, they mentioned that they had historically opposed an EC land use
    designation for the eight parcels as an inappropriate land use.
    8
    No. 50363-8-II
    I. ORDINANCE 2015-33S
    If adopted, Ordinance No. 2015-33s5 would have completed the County’s periodic review
    of and revisions to the Comprehensive Plan under GMA provision RCW 36.70A.130. As
    proposed, Ordinance No. 2015-33s (1) would have repealed and replaced the County’s
    Comprehensive Plan,6 (2) repealed the County’s Community Plans,7 (3) amended the County’s
    development regulations,8 and (4) incorporated the required regulatory periodic updates.9
    The Council’s Community Development Committee held several public meetings on
    Ordinance No. 2015-33s during June 2015. Members of the Communities gave public testimony
    during some of these meetings.
    The Council adopted Ordinance 2015-33s on June 30 as part of its periodic review of the
    Comprehensive Plan. The Pierce County Executive vetoed Ordinance 2015-33s on July 14.
    J. ORDINANCE 2015-40
    The Council then passed Ordinance No. 2015-40 on August 11. Ordinance No. 2015-40
    approved similar changes rejected in Ordinance No. 2015-33s, including approval of amendment
    5
    The record does not include a copy of Ordinance No. 2015-33s. This description comes from
    the meeting minutes for the Council’s public meeting on June 30. It is reasonable to infer that
    Ordinance No. 2015-33s included amendment M-2 because the ordinance covered the periodic
    update of which amendment M-2 was a part. The timing of this ordinance is relevant to the
    Communities’ timeliness challenge under the RCW 36.70A.130(5)(a) deadline of June 30, 2015
    for periodic update revisions.
    6
    Title 19A PCC.
    7
    Title 19B PCC.
    8
    Titles 18, 18A, 18B, 18F, 18G, and 18J PCC.
    9
    RCW 36.70A.130(1)(a).
    9
    No. 50363-8-II
    M-2. The Council approved amendment M-2 as part of its periodic review and revision to the
    Comprehensive Plan under Ordinance No. 2015-40.
    The Council made findings of fact and incorporated them into Ordinance No. 2015-40. In
    relation to amendment M-2, the Council found that the eight parcels were “inappropriately
    designated as EC” because the area was “(1) not large enough to accommodate rail spurs or heavy
    transportation infrastructure; (2) not connected with the business pattern of EC along 112th Street
    East; (3) encumbered by critical areas; and (4) surrounding incompatible uses and zoning which
    could limit EC use.” CP at 201. The Council found that because the EC land use designation was
    inappropriate, the area could “be evaluated for re-designation.” CP at 201.
    The Comprehensive Plan amendments under Ordinance No. 2015-40 became effective on
    February 1, 2016.
    III. GROWTH MANAGEMENT BOARD PROCEEDINGS
    The Communities challenged amendment M-2 in an administrative proceeding before the
    Board. They sought to invalidate Ordinance 2015-40 as inconsistent with the GMA. Apogee and
    High Valley intervened.
    The Board consolidated the Communities’ petition for review with other challenges to
    Ordinance No. 2015-40. James L. Halmo represented the other petitioners in the two cases the
    Board consolidated with the Communities’ case.
    A. THE COMMUNITIES’ ARGUMENTS BEFORE THE BOARD
    The Communities argued that the County’s approval of amendment M-2 did not comply
    with the following GMA provisions: RCW 36.70A.010, .020(5), and .130(1)(d) and (2). The
    Communities also argued that the County’s approval of amendment M-2 was inconsistent with
    10
    No. 50363-8-II
    certain local land use goals and PCC provisions. They did not clearly state why a violation of local
    policies or procedures for amendments to the comprehensive plan was a GMA violation. The
    thrust of their argument seemed to be that either the Comprehensive Plan or amendment M-2 was
    “internally inconsistent” and that amounted to a violation of RCW 36.70A.130(1)(d).10 AR at 53.
    The Communities did not argue that the County failed to provide public notice of
    amendment M-2 or that the County denied them the opportunity to participate in the proceedings
    related to amendment M-2. They also did not argue that the County’s approval of amendment M-
    2 substantially prejudiced them.
    B. THE COUNTY’S AND INTERVENORS’ ARGUMENTS BEFORE THE BOARD
    The County responded that the approval of amendment M-2 was consistent with the GMA
    and PCC provisions cited by the Communities. It argued that the “no net loss requirement” did
    not apply to amendment M-2 because it “was adopted as part of the County’s periodic update
    cycle” and because the County “evaluat[ed] the amendment using the factors identified in [former]
    PCC 19C.10.065[(A)].” AR at 1610. Additionally, it argued that amendment M-2 furthered the
    GMA’s “goal of promoting a variety of residential densities and housing types . . . under RCW
    36.70A.020(4).” AR at 1610. During oral argument before the Board, the following exchange
    occurred:
    [Intervenors’ Attorney]: . . . [T]he very first time [amendment M-2] saw
    the light of day, the staff recommended apartments only. That then went to the
    planning commission in December of 2014. They agreed. And that same proposal
    continued until it was adopted by the council in the . . . middle of 2015. So I think
    10
    RCW 36.70A.130(1)(d) provides that amendments and revisions to a county’s comprehensive
    plan must conform to the GMA and that amendments or revisions to a county’s development
    regulations must be consistent with and implement that county’s comprehensive plan.
    11
    No. 50363-8-II
    it’s fair to say from the very first outing, this proposal was changed by everybody
    who looked at it to apartments instead of the commercial center.
    [Board Member]: And “by everybody,” did that include public notice?
    [Intervenors’ Attorney]: Yes . . . well, the staff reports and everything that
    would have been done in conjunction with the --
    [Board Member]: Were published as part of a comment period?
    [Intervenors’ Attorney]: Yes, yes.
    AR Transcript of Proceedings at 57. The Communities did not contradict the Intervenors’
    comments about public notice and did not argue that the County failed to provide public notice of
    the staff reports related to amendment M-2.
    C. THE BOARD’S FINDING OF FACTS
    The Board entered the following relevant findings.
    “Applications for zoning amendments received by the July 31, 2014, deadline were . . .
    reviewed by [PALS] against the acceptance criteria in [former] PCC 19C.10.050F.” CP at 15.
    The Council “screened the PALS-accepted plan amendments through the public hearing process”
    before the Council initiated the amendments. CP at 15. Amendment M-2 “was ‘initiated’ by the
    Council in Resolution 2014-94s.” CP at 15.
    MCAC considered amendment M-2 at the November 4 public meeting. PALS advised
    MCAC “that the properties did not fit the proposed CC or existing EC designation and proposed
    an alternate designation.” CP at 15. “PALS staff evaluated the [amendment] M-2 proposal ‘based
    on’ the eight criteria identified in [former PCC 19C.10.065(A)].” CP at 23. MCAC voted to move
    forward on amendment M-2 “with the expectation that [PALS] would work toward an appropriate
    designation” to “accommodate multi-family development” on the eight parcels. CP at 15.
    PALS provided the Planning Commission with an analysis of amendment M-2 “using the
    factors in [former] PCC 19C.19.065[(A)].” CP at 16. PALS advised the Planning Commission
    12
    No. 50363-8-II
    that the eight parcels “may have been inappropriately designated EC as it did not meet the criteria,
    nor was the proposal consistent with the [Comprehensive] Plan policies for expanding CC
    designation.” CP at 16. PALS “suggested a ‘higher density residential designation’” as an
    alternative for amendment M-2. CP at 16. The Planning Commission directed PALS to prepare
    an alternative recommendation on amendment M-2 that would “accommodate high density
    residential development.” CP at 16.
    PALS prepared a modified staff report on amendment M-2 that “included text amendments
    [to the Comprehensive Plan]” adding “Moderate High Density Residential designations . . . and
    recommended its adoption.” CP at 16.
    The modified version of amendment M-2 “was adopted as part of the 2015
    [Comprehensive] Plan Update” in Ordinance 2015-40. CP at 16. The Council’s findings of fact
    attached to Ordinance 2015-40 related to the approval of amendment M-2 “indicate the proposal
    was reviewed and that attention was given to ensuring consistency with [Comprehensive] Plan
    policies.” CP at 24.
    D. THE BOARD’S CONCLUSIONS OF LAW
    The Board entered the following relevant conclusions of law.
    The plain meaning of Comprehensive Plan Policy LU-56.3.1 provides an exception to the
    “no net loss requirement” under former PCC 19A.30.030(H) (2007) and Comprehensive Plan
    Policy LU-56. CP at 18. The exception to the no net loss requirement “allows the Council to
    redesignate EC land without replacing it with ‘developable acreage’” if the County has determined
    that the land was “unsuitable for industrial use in the first place.” CP at 18. Additionally, former
    13
    No. 50363-8-II
    PCC 19C.10.055(C) “seeks to prevent the net loss of ‘developable acreage’” as opposed to “‘total
    acreage.’” CP at 19.
    The Communities “failed to show an inconsistency between the County’s development
    regulations and its [Comprehensive] Plan in violation of RCW 36.70A.130[(1)](d).” CP at 19.
    Moreover, review of Council-initiated amendments to the Comprehensive Plan under RCW
    36.70A.130(5)(a), former PCC 19C.10.055(C), and former PCC 19C.10.050(E)(3) do not require
    that a proposed amendment “be accepted as is or rejected.” CP at 23.
    The plain meaning of former PCC 19C.10.065(A) did not “require[] more than a
    recommendation based on the review” and did not require that a “proposal must necessarily
    ‘satisfy’ each and every criterion.” CP at 23. The Communities failed to show that the County
    did not evaluate amendment M-2 as required under former PCC 19C.10.065(A).
    The Communities abandoned their arguments based on alleged violations of RCW
    36.70A.010, .020(5), .130(2). The Communities also “did not allege a violation of [RCW]
    36.70A.130(5)(a).” CP at 24. Even if they had alleged a violation of RCW 36.70A.130(5)(a), it
    would “essentially [have been] a failure to act challenge and moot” because “the County ha[d]
    completed its update.” CP at 24.
    The Communities failed to show that the Board’s approval of amendment M-2 was
    inconsistent with the Comprehensive Plan, violated RCW 36.70A.130(1)(d), or violated the GMA
    generally. There was “no basis for an order of invalidity” related to amendment M-2. CP at 27.
    The Board “dismissed” all of the issues raised by the Communities. CP at 27-28.
    14
    No. 50363-8-II
    IV. THURSTON COUNTY SUPERIOR COURT PROCEEDINGS
    The Communities petitioned the Thurston County Superior Court for review of the Board’s
    decision. The superior court affirmed.
    ANALYSIS
    The Communities argue that (1) the Board erroneously interpreted or applied the law, (2)
    substantial evidence did not support the Board’s order, and (3) the Board’s order was arbitrary and
    capricious. Br. of Appellant at 6-7. We disagree.
    I. STANDARDS OF REVIEW
    Washington’s Administrative Procedure Act (APA), ch. 34.05 RCW, governs our review
    of the Board’s final decision. Whatcom County v. W. Wash. Growth Mgmt. Hr’gs Bd., 
    186 Wn.2d 648
    , 666, 
    381 P.3d 1
     (2016). “On appeal, we review ‘the Board’s decision, not the decision of the
    superior court.’” Feil v. E. Wash. Growth Mgmt. Hr’gs Bd., 
    172 Wn.2d 367
    , 376, 
    259 P.3d 227
    (2011) (quoting King County v. Cent. Puget Sound Growth Mgmt. Hr’gs Bd., 
    142 Wn.2d 543
    , 553,
    
    14 P.3d 133
     (2000). Our review is limited to “‘the record made before the Board.’” Feil, 
    172 Wn.2d at 376
     (quoting King County, 142 Wn.2d at 553).
    Under the APA, we review “the Board’s legal conclusions de novo.” Whatcom County,
    186 Wn.2d at 667. However, we give “substantial weight to the Board’s interpretation of the
    GMA.” Whatcom County, 186 Wn.2d at 667. The challenging party bears the “burden of
    establishing that the Board’s decision is based on an erroneous interpretation of the law.” Whatcom
    County, 186 Wn.2d at 667; King County, 142 Wn.2d at 553; RCW 34.05.570(3)(d).
    “Unchallenged conclusions of law become the law of the case.” Rush v. Blackburn, 
    190 Wn. App. 945
    , 956, 
    361 P.3d 217
     (2015).
    15
    No. 50363-8-II
    We review the Board’s factual findings for “substantial evidence.” Kittitas County v. E.
    Wash. Growth Mgmt. Hr’gs Bd., 
    172 Wn.2d 144
    , 155, 
    256 P.3d 1193
     (2011); City of Redmond v.
    Cent. Puget Sound Growth Mgmt. Hr’gs Bd., 
    136 Wn.2d 38
    , 46, 
    959 P.2d 1091
     (1998). Evidence
    is substantial if, “when viewed in light of the whole record,” RCW 34.05.570(3)(e), there is “‘a
    sufficient quantity of evidence to persuade a fair-minded person of the truth or correctness”’ of the
    finding. Kittitas County, 172 Wn.2d at 155 (quoting Thurston County v. W. Wash. Growth Mgmt.
    Hr’gs Bd., 
    164 Wn.2d 329
    , 341, 
    189 P.3d 38
     (2008)); see also City of Redmond, 136 Wn.2d at 46.
    The challenging party has the burden of showing that the Board’s decision is unsupported by
    substantial evidence. RCW 34.05.570(1)(a).
    “‘On mixed questions of law and fact, we determine the law independently, then apply it
    to the facts as found by the [Board.]’” Thurston County, 
    164 Wn.2d at 341
     (internal quotation
    marks omitted) (quoting Lewis County v. W. Wash. Growth Mgmt. Hr’gs Bd., 
    157 Wn.2d 488
    ,
    498, 
    139 P.3d 1096
     (2006)). We consider whether the Board’s factual findings support its
    conclusions. Kittitas County v. Kittitas County Conserv. Coal., 
    176 Wn. App. 38
    , 55 n.3, 
    308 P.3d 745
     (2013).
    We determine whether a Board’s order is arbitrary and capricious by reviewing “whether
    the order represents ‘willful and unreasoning action, taken without regard to or consideration of
    the facts and circumstances surrounding the action.”’ Kittitas County, 172 Wn.2d at 155 (quoting
    City of Redmond, 136 Wn.2d at 46-47). “‘Where there is room for two opinions, an action taken
    after due consideration is not arbitrary and capricious even though a reviewing court may believe
    it to be erroneous.’” City of Redmond, 136 Wn.2d at 47 (quoting Kendall v. Douglas, Grant,
    Lincoln & Okanogan Counties Pub. Hosp. Dist. No. 6, 
    118 Wn.2d 1
    , 14, 
    820 P.2d 497
     (1991)).
    16
    No. 50363-8-II
    II. LEGAL PRINCIPLES
    A. THE GROWTH MANAGEMENT ACT
    A purpose of the GMA is to reduce “uncoordinated and unplanned growth.” RCW
    36.70A.010. Under the GMA provision, Pierce County had to, among other things, (1) “adopt a
    countywide planning policy,” (2) “adopt a comprehensive plan,” and (3) adopt “development
    regulations that [we]re consistent with and implement[ed] the comprehensive plan.” RCW
    36.70A.040(3)(a), (d).
    A comprehensive plan is a county’s “generalized coordinated land use policy statement.”
    RCW 36.70A.030(4). “[A] comprehensive plan serves as ‘guide[s]’ or ‘blueprint[s]’ to be used in
    making land use decisions.” Feil, 172 Wn.2d at 382 (internal quotation marks omitted) (alterations
    in original) (quoting Woods v. Kittitas County, 
    162 Wn.2d 597
    , 613, 
    174 P.3d 25
     (2007)).
    “Development regulations” are a county’s “controls placed on development or land use activities,
    . . . including, but not limited to, zoning ordinances, critical areas ordinances, shoreline master
    programs, official controls, planned unit development ordinances, subdivision ordinances, and
    binding site plan ordinances,” but excluding “a decision to approve a project permit application.”
    RCW 36.70A.030(7). Development regulations need not “‘strictly conform’ to the GMA.” Feil,
    172 Wn.2d at 382 (quoting Woods, 
    162 Wn.2d at 613
    ).
    The GMA requires that a county’s comprehensive plan and development regulations
    comply with the GMA’s requirements. RCW 36.70A.130(1)(a), (d). It also requires that a
    county’s development regulations be consistent with its comprehensive plan.                  RCW
    36.70A.130(1)(a), (d).
    17
    No. 50363-8-II
    B. GROWTH MANAGEMENT HEARINGS BOARD
    1.     JURISDICTION
    A growth management hearings board has “limited jurisdiction and may decide only
    challenges to or amendments of comprehensive plans or development regulations.” Schnitzer W.,
    LLC v. City of Puyallup, 
    190 Wn.2d 568
    , 575, 
    416 P.3d 1172
     (2018). As relevant here, a Board
    may only determine whether the comprehensive plans or development regulations and
    amendments thereto comply with the GMA. Feil, 
    172 Wn.2d at 382
    ; RCW 36.70A.280(1)(a).
    2.     PRESUMPTION OF VALIDITY AND BURDEN OF PROOF
    The GMA establishes “a presumption of validity for comprehensive plans and development
    regulations,” Kittitas County, 172 Wn.2d at 155, “and amendments thereto.” RCW 36.70A.320(1).
    “[B]oards must consider anecdotal evidence provided by counties and defer to local planning
    decisions as between different planning choices that are compliant with the GMA.” Kittitas
    County, 172 Wn.2d at 157.
    A party challenging the validity of a county’s comprehensive plan or development
    regulations may rebut the presumption of validity with “evidence that persuades a board that the
    action is clearly erroneous.” Kittitas County, 172 Wn.2d at 156. The Board will review whether
    the county clearly erred “in view of the entire record . . . and in light of the goals and requirements
    of [the GMA].” Whatcom County, 186 Wn.2d at 667 (quoting RCW 36.70A.320(1), (3)). “To
    find an action clearly erroneous, the Board must be ‘left with the firm and definite conviction that
    a mistake has been committed.’” Whatcom County, 186 Wn.2d at 667 (internal quotation marks
    omitted) (quoting King County, 142 Wn.2d at 552). The challenging party has the burden of
    18
    No. 50363-8-II
    “demonstrate[ing] that any action taken by . . . a county . . . under [the GMA] is not in compliance
    with the requirements of [the GMA].” RCW 36.70A.320(2).
    III. ERRORS OF LAW
    The Communities assign error to the Board’s conclusions related to the County’s
    evaluation of amendment M-2 against the criteria for comprehensive plan amendments set forth
    under former PCC 19C.10.065(A).
    A. ARGUMENTS WAIVED OR ABANDONED BELOW REGARDING COUNTY’S EVALUATION OF
    AMENDMENT M-2
    1.     RCW 36.70A.020(5) – GMA GOALS
    The Communities argue that the Board erred in concluding that the County’s approval of
    amendment M-2 complied with GMA planning goal of encouraging economic development under
    RCW 36.70A.020(5). The Board made no such conclusion. Instead, the Board concluded that the
    Communities abandoned their argument on this issue. The Communities did not assign error to
    that conclusion.
    RCW 34.05.554(1) provides that “[i]ssues not raised before [the Board] may not be raised
    on appeal.” “Unchallenged conclusions of law become the law of the case.” Rush, 190 Wn. App.
    at 956. Thus, we do not reach the Communities’ argument based on RCW 36.70A.020(5).
    2.     OTHER GMA PROVISIONS THE COMMUNITIES CITED WITHOUT AN ASSIGNMENT OF ERROR
    The Communities also cite to several GMA provisions when discussing the County’s
    evaluation of amendment M-2.11          We address these provisions separately from RCW
    11
    RCW 36.70A.010 (“Legislative findings” on the GMA, including the public interest in
    coordinating comprehensive land use planning and economic development.); RCW 36.70A.011
    (Legislative findings on the GMA’s rural lands provisions.); RCW 36.70A.020(1), (4), and (12)
    (GMA planning goals for urban growth, housing, and public facilities and services); RCW
    19
    No. 50363-8-II
    36.70A.020(5) because the Communities did not include these provisions in their assignments of
    error, but they raise them in conclusory fashion.
    “Issues not raised before [the Board] may not be raised on appeal.” RCW 34.05.554(1).
    Additionally, a party “is deemed to have waived any issues that are not raised as assignments of
    error and argued by brief.” State v. Sims, 
    171 Wn.2d 436
    , 441, 
    256 P.3d 285
     (2011); RAP
    10.3(a)(4), (g)-(h)
    The Board concluded that the Communities abandoned their argument based on RCW
    36.70A.010, and the Communities do not assign error based on RCW 36.70A.010. Additionally,
    the Communities did not raise arguments before the Board based on RCW 36.70A.011, .020(1),
    (4), (12), .040(5)(d), or .070(2)-(4), (6). Thus, we do not reach the Communities’ argument based
    on these GMA provisions.
    B. RCW 36.70A.130(1)(D) – CONFORMANCE WITH THE GMA REQUIREMENTS AND CONSISTENCY
    WITH THE COMPREHENSIVE PLAN
    The Communities assign error to the Board’s conclusion that the Communities failed to
    show that the County violated RCW 36.70A.130(1)(d). The Communities argue that because the
    County allegedly failed to evaluate amendment M-2 as required by former PCC 19C.10.065(A),
    the County violated RCW 36.70A.130(1)(d). We disagree.
    36.70A.040(5)(d) (counties “shall adopt a comprehensive land use plan and development
    regulations that are consistent with and implement the comprehensive plan”); RCW
    36.70A.070(2)-(4), (6) (comprehensive plan mandatory elements, specifically housing, capital
    facilities, utilities, and transportation).
    20
    No. 50363-8-II
    RCW 36.70A.130(1)(d) is the only GMA provision under which the Communities
    preserved an argument related to the County’s evaluation of amendment M-2 under former PCC
    19C.10.065(A). RCW 36.70A.130(1)(d) provides that
    [a]ny amendment of or revision to a comprehensive land use plan shall conform to
    [the GMA]. Any amendment of or revision to development regulations shall be
    consistent with and implement the comprehensive plan.
    However, the GMA establishes “a presumption of validity for comprehensive plans and
    development regulations,” Kittitas County, 172 Wn.2d at 155, “and amendments thereto.” RCW
    36.70A.320(1). The party challenging an amendment to a comprehensive plan or to development
    regulations has the burden of proving that the County clearly erred. Kittitas County, 172 Wn.2d
    at 156; RCW 36.70A.130(1)(d). Therefore, to establish a violation of RCW 36.70A.130(1)(d), the
    challenging party must clearly show either that (1) an amendment or revision to the comprehensive
    plan did not conform to the GMA or (2) an amendment or revision to development regulations was
    inconsistent with or did not implement the comprehensive plan. Kittitas County, 172 Wn.2d at
    156; RCW 36.70A.130(1)(d).
    Amendment M-2 was an area-wide amendment to the Comprehensive Plan. As such, the
    second sentence of RCW 36.70A.130(1)(d) does not apply to this case because the Communities
    do not challenge a development regulation amendment. Instead, the Communities challenge a
    comprehensive plan amendment and must show that amendment M-2 did not conform to the GMA.
    RCW 36.70A.130(1)(d).
    The Communities cite no authority to support the proposition that a County’s alleged
    failure to adhere to its procedures for amendments to the comprehensive plan violates RCW
    36.70A.130(1)(d). It is the Communities’ burden to show that the amendment did not conform to
    21
    No. 50363-8-II
    the GMA. Kittitas County, 172 Wn.2d at 156; RCW 36.70A.320(2), .130(1)(d). “[B]oards must
    . . . defer to local planning decisions as between different planning choices that are compliant with
    the GMA.” Kittitas County, 172 Wn.2d at 157.
    The GMA does not require an evaluation of the eight factors enumerated under former
    PCC 19C.10.065(A).       And the Board concluded that the plain meaning of former PCC
    19C.10.065(A) did not “require[] more than a recommendation based on the review” and did not
    require that a “proposal must necessarily ‘satisfy’ each and every criterion.” CP at 23. The
    Communities failed to show that the County did not evaluate amendment M-2 as required under
    former PCC 19C.10.065(A).
    Even if the County failed to evaluate amendment M-2 as required by former PCC
    19C.10.065(A), the Communities have failed to show that alleged failure means that amendment
    M-2 to the Comprehensive Plan does not conform to the GMA.
    We give “substantial weight to the Board’s interpretation of the GMA.” Whatcom County,
    186 Wn.2d at 667. Here, the Board concluded that the Communities failed to show a violation of
    RCW 36.70A.130(1)(d). We hold that the Board did not err.12
    IV. SUBSTANTIAL EVIDENCE
    The Communities argue that substantial evidence does not support the Board’s conclusion
    that the County evaluated amendment M-2 as required under former PCC 19C.10.065(A). The
    Communities seem to argue that there is no evidence that PALS evaluated the HRD redesignation
    12
    As a result, we do not reach the Communities’ specific arguments that the County failed to
    properly evaluate the amendment under former PCC 19C.10.065(A). In any event, the
    Communities waived their argument on the Board’s interpretation of former PCC 19C.10.065(A)
    by failing to support it with analysis or authority. RAP 10.3(a)(6).
    22
    No. 50363-8-II
    or “facts and evidence” related to the factors under former PCC 19C.10.065(A)(1)-(3), (5), and
    (7)-(8). Br. of Communities at 17.
    A. BURDEN OF PROOF
    The Board concluded that the Communities did not show by clear error “that the County
    failed to evaluate . . . amendment [M-2] as required by [former] PCC 19C.10.065[(A)].” CP at 24;
    Kittitas County, 172 Wn.2d at 156 (parties challenging a comprehensive plan amendment may
    rebut the presumption of validity with “evidence that persuades a board that the action is clearly
    erroneous”).
    The Communities seem to suggest that the County has the burden of demonstrating that
    substantial evidence supports the Board’s decision. However, the Communities have the burden
    of showing that substantial evidence did not support the Board’s decision. RCW 34.05.570(1)(a).
    B. EVALUATION OF THE AMENDMENT
    The Communities argue that substantial evidence does not support the Board’s decision
    because there is no evidence that PALS evaluated the HRD redesignation. They argue that PALS’
    evaluation of the CC redesignation was insufficient because “the answers to the eight questions
    provided under [former] PCC 19C.10.065(A)[] would be substantively different depending on
    whether EC was being redesignated to CC . . . or to [HRD].” Br. of Communities at 22-23. We
    hold that the Communities’ argument fails.
    The following evidence indicates that PALS evaluated the HRD redesignation. PALS
    initial staff report “question[ed] whether a higher density residential designation may be more
    appropriate as a transition into the surrounding neighborhood.” CP at 130 (emphasis added).
    Importantly, that report discussed the eight factors under former PCC 19C.10.065(A). The
    23
    No. 50363-8-II
    Planning Commission noted that PALS would work with MCAC “as part of the Comprehensive
    Plan update if they want to see [the eight parcels] redesignated to a different designation more
    appropriate for the site, such as High Density Residential (HRD) . . . implemented with a[]
    Moderate High Density Residential (MHR) [zone] classification.” CP at 168. The Planning
    Commission noted that the addition of an HRD land use designation and implementing MHR zone
    classification “was vetted with [the] Economic Development Department.” CP at 168. The
    Planning Commission approved a motion to have PALS “prepare an alternative recommendation
    to accommodate high density residential development.” CP at 169.
    PALS then “reviewed [additional] information and modified its recommendation for
    [amendment] M-2” in an errata to its initial staff report. CP at 172 (emphasis added). PALS’
    modified recommendation was for redesignation of the eight parcels from an EC to an HRD land
    use designation, along with an implementing MHR zoning classification, “as it would be more
    appropriate as a transition into the surrounding neighborhood.” CP at 173. PALS did not modify
    the discussion of the eight factors under former PCC 19C.10.065(A) in the errata.
    We reject the Communities’ challenge because substantial evidence shows that PALS
    evaluated the HRD designation.
    C.     USE OF THE FACTORS TO DEVELOP AN EVALUATION OF THE AMENDMENT
    The Communities argue that there is no evidence that the County evaluated the factors
    under former PCC 19C.10.065(A)(1) or (3). They also argue that there is no evidence that the
    County evaluated “facts and evidence” related to the factors under former PCC 19C.10.065(A)(2),
    (5), and (7)-(8). Br. of Communities at 17. We hold that the Communities’ argument fails.
    24
    No. 50363-8-II
    Former PCC 19C.10.065(A) provides the following factors shall be considered when
    evaluating an amendment:
    1.      Is there a community or countywide need for the proposed amendment? If
    so, what is that need?
    2.      Is the infrastructure available to support the requested amendment, such as
    sewer, water, roads, schools, fire support?
    3.      Would the requested amendment provide public benefits? If so, what sorts
    of public benefits?
    4.      Are there physical constraints on the property?
    5.      Are there environmental constraints, such as noise, access, traffic, hazard
    areas on or adjacent to the proposed amendment?
    6.      What types of land use or activities are located on the property?
    7.      What types of land use or activities are located on neighboring properties?
    8.      Is the proposed amendment consistent with all applicable state and local
    planning policies?
    The Board concluded that the plain meaning of former PCC 19C.10.065(A) did not
    “require[] more than a recommendation based on the review” and did not require that a “proposal
    must necessarily ‘satisfy’ each and every criterion.” CP at 23. And the plain language of former
    PCC 19C.10.065(A) requires that PALS evaluate a Council-initiated amendment, not the factors
    or facts related to those factors. Additionally, no one factor is determinative.
    Moreover, we do not consider the Communities’ argument under each of the factors
    because they failed to raise those arguments before the Board and thus waived them or they do not
    support the arguments with authority here. RCW 34.05.554(1) (waiver of arguments not raised
    before the Board); RAP 10.3(a)(6) (“citations to legal authority” must support an argument).
    Based on the foregoing, we hold that the Communities failed to meet their burden of
    showing that substantial evidence did not support the Board’s decision.
    25
    No. 50363-8-II
    V. ARBITRARY AND CAPRICIOUS ARGUMENT
    The Communities assign error to the Board’s alleged failure to consider the fact that the
    eight parcels redesignated by amendment M-2 are adjacent to rural separator designated lands and
    argue that the Board’s decision was arbitrary and capricious as a result. Again, we disagree.
    The Board’s order is arbitrary and capricious if it “represents ‘willful and unreasoning
    action, taken without regard to or consideration of the facts and circumstances surrounding the
    action.”’ Kittitas County, 172 Wn.2d at 155 (quoting City of Redmond, 136 Wn.2d at 46-47).
    “‘Where there is room for two opinions, an action taken after due consideration is not arbitrary
    and capricious even though a reviewing court may believe it to be erroneous.’” City of Redmond,
    136 Wn.2d at 47 (quoting Kendall, 
    118 Wn.2d at 14
    ).
    A petitioner challenging a Board decision must include “argument in support of the issues
    presented for review, together with citations to legal authority and references to relevant parts of
    the record.” RAP 10.3(a)(6). “Unsubstantiated assignments of error are deemed abandoned.”
    Kittitas County, 176 Wn. App. at 54. “[R]equiring an actual challenge prior to undertaking
    appellate review avoids ‘the danger of an erroneous decision caused by the failure of parties . . . to
    zealously advocate their position.’” Clark County v. W. Wash. Growth Mgmt. Hr’gs Bd., 
    177 Wn.2d 136
    , 144, 
    298 P.3d 704
     (2013) (alteration in original) (quoting Orwick v. City of Seattle,
    
    103 Wn.2d 249
    , 253, 
    692 P.2d 793
     (1984)).
    Here, the Communities did not set out a separate section in their brief devoted to the
    arbitrary and capricious argument. Instead, the Communities merely mention the Board’s alleged
    failure to “consider the Rural Separator community to the south” of the eight parcels in the portion
    26
    No. 50363-8-II
    of their brief addressing PALS’ evaluation of former PCC 19C.10.065(A)(7) and (8). Br. of
    Communities at 25.
    The Communities do not allege any facts showing that any failure of the Board to consider
    the rural separator to the south of the eight parcels was willful. They state only that “[t]o the extent
    that the Board’s decision constitutes a ‘willful and unreasoning action’ to not consider the Rural
    Separator community to the south, the Board’s decision would also appear arbitrary and
    capricious.” Br. of Communities at 25. The Communities also do not support the argument with
    authority.
    Moreover, the Board did consider the land use south of the eight parcels when it determined
    that PALS properly evaluated amendment M-2. The Board included a finding in its order that the
    eight parcels “are immediately north of 121st [Street] E[ast], within the UGA.” CP at 14. In the
    portion of its order discussing other adjacent land uses, the Board cited to the application for
    amendment M-2, which included a map showing the abbreviations for the rural separator
    designation and zone classification. During oral argument before the Board, the County also
    mentioned that a rural separator designated lands abutted the eight parcels to the south.
    We hold that the Communities abandoned their arbitrary and capricious argument and they
    failed to meet their burden of proof on the argument.
    In sum, the Board did not err when it concluded that the Communities failed to show that
    the County did not evaluate amendment M-2 as required by former PCC 19C.10.065(A), and
    therefore the Communities failed to show that amendment M-2 violated the GMA. Substantial
    evidence supports the Board’s conclusion and its decision was not arbitrary nor capricious.
    27
    No. 50363-8-II
    VI. PUBLIC NOTICE AND PARTICIPATION
    The Communities assign error to the Board’s conclusion that the County’s approval of
    amendment M-2 complied with the GMA’s public notice and participation requirements under
    RCW 36.70A.020(11), .140, and .035.13 However, the Board made no such conclusion. Because
    the Communities’ argument rests on an incorrect assumption that the Board made a conclusion it
    did not make, the Communities’ argument fails.
    The County argues that the Communities waived the issues of public notice and public
    participation by failing to raise them before the Board. It argues that it did not have a chance to
    develop the record to demonstrate that it provided the required public notice and opportunity for
    public participation.
    The Communities reply that interests of justice would be served by reviewing the issue of
    public notice as provided under RCW 34.05.554(1)(d)(ii). Alternatively, the Communities argue
    that this court should review the issue of public notice because they raised it before the Thurston
    County Superior Court. They also argue that the issues of public notice and public participation
    warrant review based on City of Seattle v. McCready, 
    123 Wn.2d 260
    , 269, 
    868 P.2d 134
     (1994),
    Maynard Invest. Co. v. McCann, 
    77 Wn.2d 616
    , 623, 
    465 P.2d 657
     (1970), or RAP 10.6(c) and
    12.1(b).
    We agree with the County.
    13
    They also assign error to alleged public notice and participation requirements under RCW
    36.70A.130(1)(d), but that provision does not discuss public notice and participation.
    28
    No. 50363-8-II
    A. RCW 34.05.554(1)(d)(ii)
    “Issues not raised before [the Board] may not be raised on appeal.” RCW 34.05.554(1).
    An exception exists if “[t]he interests of justice would be served by resolution of an issue arising
    from: . . . [a]gency action occurring after the person exhausted the last feasible opportunity for
    seeking relief from the agency.” RCW 34.05.554(1)(d)(ii).
    Here, the Communities seem to argue that the Board’s one question about public notice
    during argument satisfied the requirements of RCW 34.05.554(1)(d)(ii). It did not. The County’s
    alleged failure to provide notice, happened before the Communities filed their petition with the
    Board. Thus we cannot conclude that the public notice issue arose from an action after the
    Communities had “exhausted the last feasible opportunity for seeking relief” from the Board.
    RCW 34.05.554(1)(d)(ii).
    Therefore, we decline to extend the exception to the general rule under RCW
    35.05.554(1)(d)(ii) to this case.
    B. ISSUES RAISED BEFORE THE THURSTON COUNTY SUPERIOR COURT
    “On appeal, we review ‘the Board’s decision, not the decision of the superior court.’” Feil,
    172 Wn.2d at 376 (quoting King County, 142 Wn.2d at 553). Our review is limited to “‘the record
    made before the Board.’” Feil, 
    172 Wn.2d at 376
     (internal quotation marks omitted) (quoting
    King County, 142 Wn.2d at 553). We hold that the Communities’ argument that they preserved
    the issue of public notice by raising it before the Thurston County Superior Court is meritless.
    29
    No. 50363-8-II
    C. ISSUES NECESSARY TO A DECISION
    The Communities rely on McCready, 
    123 Wn.2d at 269
    ,14 to argue that this court should
    review the otherwise waived issues of public notice and public participation because they are
    necessary. In McCready, our Supreme Court noted that “[o]rdinarily, the failure of the parties to
    raise an issue would preclude its examination.” 
    123 Wn.2d at 269
    . However, the court recognized
    that appellate courts have “discretionary authority to reach” such issues “if the parties ignore a
    constitutional mandate, a statutory commandment, or an established precedent” that is “necessary
    for decision.” McCready, 
    123 Wn.2d at 269
    . The Communities do not analyze whether “the
    parties ignore[d] a constitutional mandate, a statutory commandment, or an established precedent.”
    McCready, 
    123 Wn.2d at 269
    . Therefore, we decline to extend the exception to the general rule
    announced in McCready to this case.
    D. ISSUES AFFECTING THE PUBLIC INTEREST
    The Communities also cite to Maynard, 
    77 Wn.2d at 622-23
    , for the proposition that this
    court may review the issues of public notice and public participation because they “‘affect[ ] the
    public interest.’” Amended Reply Br. of Communities at 18 (quoting Maynard, 
    77 Wn.2d at 622
    ).
    In Maynard, our Supreme Court stated that the “ordinary rule” is that “errors not raised below will
    not be considered on appeal.” 
    77 Wn.2d at 621
    . The court recognized an exception to that rule,
    where the issue “affects the public interest” and involves “the present welfare of the people at
    14
    The Communities also cite to Hall v. American National Plastics, Inc., 
    73 Wn.2d 203
    , 205, 
    437 P.2d 693
     (1968) (permitting courts to reach otherwise waived issues that are “determinative” and
    “crucial”), and Conrad v. University of Washington, 
    119 Wn.2d 519
    , 527-28, 
    834 P.2d 17
     (1992)
    (permitting otherwise waived due process claims). However, the Communities fail to explain how
    those cases are analogous to this case.
    30
    No. 50363-8-II
    large, or a substantial portion thereof.” 
    77 Wn.2d at 622
    . The Communities do not argue that the
    issues of public notice and the opportunity for public participation in this case involve the public
    interest and present welfare of the public at large. Therefore, we decline to extend the exception
    to the general rule announced in Maynard to this case.
    E. RULES OF APPELLATE PROCEDURE
    The Communities rely on RAP 10.6(c) and 12.1(b) to argue that this court should review
    the otherwise waived issues of public notice and public participation because they are “important
    to proper adjudication.” Amended Reply Br. of Communities at 18.
    RAP 10.6(c) provides that appellate courts “may ask for an amicus brief at any stage of
    review.” The rule does not apply to this case.
    RAP 12.1(b) provides that an appellate court may provide an opportunity for supplemental
    briefing if the court “concludes that an issue which is not set forth in the briefs should be considered
    to properly decide a case.” We do not consider the issues of public notice and public participation
    to be necessary to properly decide this case because even with supplemental briefing, our review
    is limited to “‘the record made before the Board.’” Feil, 
    172 Wn.2d at 376
     (internal quotation
    marks omitted) (quoting King County, 142 Wn.2d at 553). Because the County did not have an
    opportunity to develop the record made before the Board on those issues, we decline to request
    supplemental briefing.
    In conclusion, because the Communities have failed to demonstrate that an exception to
    the general rule of waiver applies, we hold that the Communities have waived the issues of public
    notice and public participation by failing to raise them below.
    31
    No. 50363-8-II
    VII. TIMELINESS OF COMPREHENSIVE PLAN AMENDMENTS
    The Communities assign error to the Board’s conclusions that the County’s approval of
    amendment M-2 complied with the statutory deadline under RCW 36.70A.130(5)(a). However,
    the Board made no such conclusion.
    The Board concluded that (1) the Communities “did not allege a violation of [RCW]
    36.70A.130(5)(a)”15 and (2) if they had, “the allegation [wa]s essentially a failure to act challenge
    and moot at [the] time as the County ha[d] completed its update.” CP at 24. Again, because the
    Communities’ argument rests on a conclusion that the Board did not make, their argument fails.
    As to the conclusion that the Board did make, the Communities argue that the failure to act
    challenge was not moot because the County did not provide public notice or an opportunity for
    public participation as required under the GMA. The Communities did not assign error to the
    Board’s conclusions that (1) the Communities failed to state a RCW 36.70A.130(5)(a) claim or (2)
    the Communities were instead raising a failure to act challenge. The Communities also argue that
    substantial evidence did not support the Board’s decision on RCW 36.70A.130(5)(a) because the
    County did not revise the Comprehensive Plan before the June 30 deadline. These arguments fail.
    “A case is moot if a court can no longer provide effective relief.” Orwick, 
    103 Wn.2d at 253
    . Under the GMA, the only relief the Board may provide is “a finding of noncompliance’” or
    “‘a finding of invalidity.’” Whatcom County, 186 Wn.2d at 694 (quoting Town of Woodway v.
    Snohomish County, 
    180 Wn.2d 165
    , 174, 
    322 P.3d 1219
     (2014)); RCW 36.70A.300(3)(b), .302.
    15
    To state a claim for a County’s failure to review and revise a comprehensive plan before the
    June 30, 2015 deadline under RCW 36.70A.130(5)(a), a party must allege that the legislature
    “adopted or substantively amended [an underlying GMA provision] since the previous [version of
    the] comprehensive plan was adopted or updated.” Thurston County, 
    164 Wn.2d at 344
    ; see Save
    Our Scenic Area v. Skamania County, 
    183 Wn.2d 455
    , 466-67, 
    352 P.3d 177
     (2015).
    32
    No. 50363-8-II
    The County had to review and, if necessary, update its comprehensive plan and development
    regulations by June 30, 2015. RCW 36.70A.130(5)(a). A party must support its assignments of
    error with argument and authority. RAP 10.3(a)(6). “Unsubstantiated assignments of error are
    deemed abandoned.” Kittitas County, 176 Wn. App. at 54.
    The Communities do not argue that the Board can still provide effective relief for the
    County’s failure to review and revise its Comprehensive Plan by the deadline.              And the
    Communities waived any argument based on public notice or an opportunity for public
    participation by failing to raise those issues before the Board. RCW 34.05.554(1). Even if the
    Communities had preserved those arguments, they provide no argument or authority explaining
    how the Board could provide effective relief for the County’s alleged failure to make revisions by
    the June 30 deadline. Therefore, we hold that the Board did not err when it concluded that the
    Communities’ challenge under RCW 36.70A.130(5)(a) was moot.
    VIII. SUBSTANTIAL PREJUDICE
    The Communities assign error to the Board’s conclusion that the County’s approval of
    amendment M-2 did not substantially prejudice them. This assignment of error fails.
    A petitioner challenging a Board decision must include “argument in support of the issues
    presented for review, together with citations to legal authority and references to relevant parts of
    the record.” RAP 10.3(a)(6). “Unsubstantiated assignments of error are deemed abandoned.”
    Kittitas County, 176 Wn. App. at 54.
    The portion of the Communities’ brief addressing prejudice does not explain why they are
    addressing the issue of prejudice and does not cite to any authority. We hold that the Communities
    have abandoned the assignment of error based on substantial prejudice.
    33
    No. 50363-8-II
    IX. CONCLUSION
    We presume that local planning actions are valid under the GMA. The Communities failed
    to show that the County’s alleged failure to adhere to former PCC 19C.10.065(A) resulted in an
    amendment M-2 that was inconsistent with the GMA. We hold that the Board did not err as a
    matter of law, that its order was supported by substantial evidence, and that the Board’s decision
    was not arbitrary nor capricious.
    Further, we hold that the Communities waived their public notice and public participation
    arguments by failing to raise them before the Board. They did not show that any exception to the
    waiver rule applies. The Communities also did not show that the Board erred in concluding that
    the Communities’ claim regarding the County’s alleged failure to review and revise the
    Comprehensive Plan by the GMA deadline was moot. Finally, the Communities failed to support
    their substantial prejudice argument with authority or facts. For these reasons, we affirm.
    A majority of the panel having determined that this opinion will not be printed in the
    Washington Appellate Reports, but will be filed for public record in accordance with RCW 2.06.040,
    it is so ordered.
    JOHANSON, J.
    We concur:
    WORSWICK, P.J.
    MELNICK, J.
    34