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    <ReturnTs>2025-03-28T08:50:54-05:00</ReturnTs>
    <TaxPeriodEndDt>2024-12-31</TaxPeriodEndDt>
    <ReturnTypeCd>990EZ</ReturnTypeCd>
    <TaxPeriodBeginDt>2024-01-01</TaxPeriodBeginDt>
    <Filer>
      <EIN>842489665</EIN>
      <BusinessName>
        <BusinessNameLine1Txt>Mills River Rescue and Sanctuary Inc</BusinessNameLine1Txt>
      </BusinessName>
      <InCareOfNm>% Marilyn O'Connell</InCareOfNm>
      <BusinessNameControlTxt>MILL</BusinessNameControlTxt>
      <PhoneNum>5082694323</PhoneNum>
      <USAddress>
        <AddressLine1Txt>240 River Road</AddressLine1Txt>
        <CityNm>Marstons Mills</CityNm>
        <StateAbbreviationCd>MA</StateAbbreviationCd>
        <ZIPCd>02648</ZIPCd>
      </USAddress>
    </Filer>
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      <PersonNm>MARILYN O'CONNELL</PersonNm>
      <PersonTitleTxt>Treasurer</PersonTitleTxt>
      <PhoneNum>5082694323</PhoneNum>
      <SignatureDt>2025-03-28</SignatureDt>
    </BusinessOfficerGrp>
    <IRSResponsiblePrtyInfoCurrInd>true</IRSResponsiblePrtyInfoCurrInd>
    <TaxYr>2024</TaxYr>
    <BuildTS>2025-03-06 01:10:19Z</BuildTS>
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      <GrossSalesOfInventoryAmt>6377</GrossSalesOfInventoryAmt>
      <CostOfGoodsSoldAmt>3398</CostOfGoodsSoldAmt>
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      <TotalRevenueAmt>135299</TotalRevenueAmt>
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      <NetAssetsOrFundBalancesBOYAmt>47092</NetAssetsOrFundBalancesBOYAmt>
      <NetAssetsOrFundBalancesEOYAmt>78006</NetAssetsOrFundBalancesEOYAmt>
      <CashSavingsAndInvestmentsGrp>
        <BOYAmt>26530</BOYAmt>
        <EOYAmt>44802</EOYAmt>
      </CashSavingsAndInvestmentsGrp>
      <LandAndBuildingsGrp>
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        <EOYAmt>33204</EOYAmt>
      </LandAndBuildingsGrp>
      <OtherAssetsTotalDetail>
        <BOYAmt>0</BOYAmt>
        <EOYAmt>0</EOYAmt>
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      <Form990TotalAssetsGrp>
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        <EOYAmt>78006</EOYAmt>
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      <SumOfTotalLiabilitiesGrp>
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        <EOYAmt>0</EOYAmt>
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      <NetAssetsOrFundBalancesGrp>
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        <EOYAmt>78006</EOYAmt>
      </NetAssetsOrFundBalancesGrp>
      <PrimaryExemptPurposeTxt>The care of the animals at the rescue.</PrimaryExemptPurposeTxt>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>Provide food and shelter; veterinarian, farrier, dental and training services for the various animals. Upkeep of the building and grounds Where they are sheltered.</DescriptionProgramSrvcAccomTxt>
        <ProgramServiceExpensesAmt>106338</ProgramServiceExpensesAmt>
      </ProgramSrvcAccomplishmentGrp>
      <TotalProgramServiceExpensesAmt>106338</TotalProgramServiceExpensesAmt>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>PATTI MARONEY</PersonNm>
        <TitleTxt>President clerk</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>0.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
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      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>MARILYN O'CONNELL</PersonNm>
        <TitleTxt>Treasurer</TitleTxt>
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        <CompensationAmt>0</CompensationAmt>
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        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>WENDY PARKER SMITH</PersonNm>
        <TitleTxt>Director</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>0.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>JANICE SCHOFIELD</PersonNm>
        <TitleTxt>Director</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>0.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <ActivitiesNotPreviouslyRptInd>false</ActivitiesNotPreviouslyRptInd>
      <ChgMadeToOrgnzngDocNotRptInd>false</ChgMadeToOrgnzngDocNotRptInd>
      <OrganizationHadUBIInd>false</OrganizationHadUBIInd>
      <SubjectToProxyTaxInd>false</SubjectToProxyTaxInd>
      <OrganizationDissolvedEtcInd>false</OrganizationDissolvedEtcInd>
      <Form1120PolFiledInd>false</Form1120PolFiledInd>
      <MadeLoansToFromOfficersInd>false</MadeLoansToFromOfficersInd>
      <EngagedInExcessBenefitTransInd>false</EngagedInExcessBenefitTransInd>
      <BooksInCareOfDetail>
        <PersonNm>MARILYN O'CONNELL</PersonNm>
        <USAddress>
          <AddressLine1Txt>312 Aegean Vista Way</AddressLine1Txt>
          <CityNm>Saint Augustine</CityNm>
          <StateAbbreviationCd>FL</StateAbbreviationCd>
          <ZIPCd>32080</ZIPCd>
        </USAddress>
        <PhoneNum>5082694323</PhoneNum>
      </BooksInCareOfDetail>
      <ForeignFinancialAccountInd>false</ForeignFinancialAccountInd>
      <ForeignOfficeInd>false</ForeignOfficeInd>
      <DonorAdvisedFndsInd>false</DonorAdvisedFndsInd>
      <OperateHospitalInd>false</OperateHospitalInd>
      <TanningServicesProvidedInd>false</TanningServicesProvidedInd>
      <RelatedOrganizationCtrlEntInd>false</RelatedOrganizationCtrlEntInd>
      <PoliticalCampaignActyInd>false</PoliticalCampaignActyInd>
      <LobbyingActivitiesInd>false</LobbyingActivitiesInd>
      <SchoolOperatingInd>false</SchoolOperatingInd>
      <TrnsfrExmptNonChrtblRltdOrgInd>false</TrnsfrExmptNonChrtblRltdOrgInd>
      <PartVIOfCompOfHghstPdEmplTxt>NONE</PartVIOfCompOfHghstPdEmplTxt>
      <PartVIHghstPdCntrctProfSrvcTxt>NONE</PartVIHghstPdCntrctProfSrvcTxt>
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        <CurrentTaxYearMinus2YearsAmt>94867</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>105897</CurrentTaxYearMinus1YearAmt>
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        <CurrentTaxYearAmt>21536</CurrentTaxYearAmt>
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        <CurrentTaxYearAmt>142378</CurrentTaxYearAmt>
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      <PublicSupportCY509Pct>1.00000</PublicSupportCY509Pct>
      <PublicSupportPY509Pct>1.00000</PublicSupportPY509Pct>
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      <InvestmentIncomePYPct>0.00000</InvestmentIncomePYPct>
      <ThirtyThrPctSuprtTestsCY509Ind>X</ThirtyThrPctSuprtTestsCY509Ind>
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          <BusinessNameLine1>RESTRICTED</BusinessNameLine1>
        </ContributorBusinessName>
        <ContributorUSAddress>
          <AddressLine1>RESTRICTED</AddressLine1>
          <AddressLine2>RESTRICTED</AddressLine2>
          <City>RESTRICTED</City>
          <State>RESTRICTED</State>
          <ZIPCode>RESTRICTED</ZIPCode>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I Line 16</FormAndLineReferenceDesc>
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      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I Line 16</FormAndLineReferenceDesc>
        <ExplanationTxt>Animal expenses $75060.00</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I Line 16</FormAndLineReferenceDesc>
        <ExplanationTxt>General office $1653.00</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I Line 16</FormAndLineReferenceDesc>
        <ExplanationTxt>gas $993.00</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part II Line 26</FormAndLineReferenceDesc>
        <ExplanationTxt>Accounts payable and accrued expenses. Beginning:$6700.00 Ending: $0.00</ExplanationTxt>
      </SupplementalInformationDetail>
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