diff --git a/src/Utilities/Idm/SourceContext.f90 b/src/Utilities/Idm/SourceContext.f90
index b833f31e6ec..3f25ef7d75f 100644
--- a/src/Utilities/Idm/SourceContext.f90
+++ b/src/Utilities/Idm/SourceContext.f90
@@ -23,7 +23,7 @@ module InputModelContextModule
 
   !> @brief type for storing model context
   !!
-  !! This type is used to store a list of context objects
+  !! This type is used to store a set of context objects
   !! associated with a model. Add additional context types as
   !! appropriate.
   !!
@@ -31,7 +31,7 @@ module InputModelContextModule
   type :: ModelContextType
     character(len=LENMODELNAME) :: modelname !< name of model
     character(len=LINELENGTH) :: modelfname !< name of model input file
-    type(NC4ModelInputsType), pointer :: nc4_context
+    type(NC4ModelInputsType), pointer :: nc4_context !< model netcdf context
   contains
     procedure :: init => modelctx_init
     procedure :: destroy => modelctx_destroy
@@ -148,7 +148,11 @@ subroutine ModelContextDestroy()
     return
   end subroutine ModelContextDestroy
 
-  !> @brief get model context object from list
+  !> @brief add netcdf context to model context object
+  !!
+  !! Add netcdf context to a model on the model context list.
+  !! If model context object does not exist, create and add
+  !! to the model context list.
   !!
   !<
   subroutine AddModelNC4Context(modelname, modelfname, nc4_context)
@@ -177,7 +181,10 @@ subroutine AddModelNC4Context(modelname, modelfname, nc4_context)
     return
   end subroutine AddModelNC4Context
 
-  !> @brief get model context object from list
+  !> @brief get netcdf context associated with model
+  !!
+  !! Retrieve and return netcdf context associated with a model
+  !! context object on the model context list.
   !!
   !<
   function GetModelNC4Context(modelname) result(nc4_context)
diff --git a/src/Utilities/Idm/mf6blockfile/AsciiInputLoadType.f90 b/src/Utilities/Idm/mf6blockfile/AsciiInputLoadType.f90
index 081f31f1579..978559b83c9 100644
--- a/src/Utilities/Idm/mf6blockfile/AsciiInputLoadType.f90
+++ b/src/Utilities/Idm/mf6blockfile/AsciiInputLoadType.f90
@@ -8,8 +8,10 @@
 module AsciiInputLoadTypeModule
 
   use KindModule, only: DP, I4B, LGP
+  use ConstantsModule, only: LENVARNAME
   use InputLoadTypeModule, only: DynamicPkgLoadType
   use BlockParserModule, only: BlockParserType
+  use BoundInputContextModule, only: BoundInputContextType
 
   implicit none
   private
@@ -19,6 +21,10 @@ module AsciiInputLoadTypeModule
   !!
   !<
   type, abstract, extends(DynamicPkgLoadType) :: AsciiDynamicPkgLoadBaseType
+    integer(I4B) :: nparam
+    character(len=LENVARNAME), dimension(:), &
+      allocatable :: param_names !< dynamic param names
+    type(BoundInputContextType) :: bndctx
   contains
     procedure(ascii_period_load_if), deferred :: rp
   end type AsciiDynamicPkgLoadBaseType
diff --git a/src/Utilities/Idm/mf6blockfile/IdmMf6File.f90 b/src/Utilities/Idm/mf6blockfile/IdmMf6File.f90
index b2845e1d74a..8f0fe795be4 100644
--- a/src/Utilities/Idm/mf6blockfile/IdmMf6File.f90
+++ b/src/Utilities/Idm/mf6blockfile/IdmMf6File.f90
@@ -36,7 +36,7 @@ module IdmMf6FileModule
   !!
   !<
   type :: PackageLoad
-    procedure(IPackageLoad), nopass, pointer, public :: load_package => null() !< procedure pointer to the load routine
+    procedure(IPackageLoad), nopass, pointer, public :: load_package !< procedure pointer to the load routine
   end type PackageLoad
 
   abstract interface
@@ -63,9 +63,9 @@ end subroutine IPackageLoad
   !<
   type, extends(DynamicPkgLoadBaseType) :: Mf6FileDynamicPkgLoadType
     type(BlockParserType), pointer :: parser !< parser for MF6File period blocks
-    integer(I4B), pointer :: iper => null()
-    integer(I4B), pointer :: ionper => null()
-    class(AsciiDynamicPkgLoadBaseType), pointer :: block_loader => null()
+    integer(I4B), pointer :: iper
+    integer(I4B), pointer :: ionper
+    class(AsciiDynamicPkgLoadBaseType), pointer :: rp_loader
   contains
     procedure :: init => dynamic_init
     procedure :: df => dynamic_df
@@ -104,6 +104,9 @@ subroutine input_load(filename, mf6_input, component_filename, iout, &
     type(PackageLoad) :: pkgloader
     integer(I4B) :: inunit
     !
+    ! -- initialize
+    nullify (pkgloader%load_package)
+    !
     ! -- set parser based package loader by file type
     select case (mf6_input%pkgtype)
     case default
@@ -156,15 +159,17 @@ end subroutine static_init
 
   !> @brief load routine for static loader
   !<
-  function static_load(this, iout) result(period_loader)
+  function static_load(this, iout) result(rp_loader)
     class(Mf6FileStaticPkgLoadType), intent(inout) :: this
     integer(I4B), intent(in) :: iout
-    class(DynamicPkgLoadBaseType), pointer :: period_loader
-    class(Mf6FileDynamicPkgLoadType), pointer :: mf6_loader => null()
-    type(BlockParserType), pointer :: parser => null()
+    class(DynamicPkgLoadBaseType), pointer :: rp_loader
+    class(Mf6FileDynamicPkgLoadType), pointer :: mf6_loader
+    type(BlockParserType), pointer :: parser
     !
     ! -- initialize
-    nullify (period_loader)
+    nullify (rp_loader)
+    nullify (mf6_loader)
+    nullify (parser)
     !
     ! -- load model package to input context
     if (this%iperblock > 0) then
@@ -185,7 +190,7 @@ function static_load(this, iout) result(period_loader)
       call mf6_loader%set(parser)
       !
       ! -- set return pointer to base dynamic loader
-      period_loader => mf6_loader
+      rp_loader => mf6_loader
       !
     else
       !
@@ -228,6 +233,8 @@ subroutine dynamic_init(this, mf6_input, modelname, modelfname, source, &
     call mem_allocate(this%iper, 'IPER', this%mf6_input%mempath)
     call mem_allocate(this%ionper, 'IONPER', this%mf6_input%mempath)
     !
+    ! -- initialize package
+    nullify (this%rp_loader)
     this%iper = 0
     this%ionper = 0
     !
@@ -261,7 +268,7 @@ subroutine dynamic_df(this)
     ! -- read first iper
     call this%read_ionper()
     !
-    call this%block_loader%df()
+    call this%rp_loader%df()
     !
     ! -- return
     return
@@ -272,7 +279,7 @@ end subroutine dynamic_df
   subroutine dynamic_ad(this)
     class(Mf6FileDynamicPkgLoadType), intent(inout) :: this
     !
-    call this%block_loader%ad()
+    call this%rp_loader%ad()
     !
     ! -- return
     return
@@ -283,7 +290,6 @@ end subroutine dynamic_ad
   subroutine dynamic_rp(this)
     ! -- modules
     use TdisModule, only: kper, nper
-    use MemoryManagerModule, only: mem_setptr
     ! -- dummy
     class(Mf6FileDynamicPkgLoadType), intent(inout) :: this
     ! -- locals
@@ -292,7 +298,7 @@ subroutine dynamic_rp(this)
     if (this%ionper /= kper) return
     !
     ! -- dynamic load
-    call this%block_loader%rp(this%parser)
+    call this%rp_loader%rp(this%parser)
     !
     ! -- update loaded iper
     this%iper = kper
@@ -372,19 +378,19 @@ subroutine dynamic_create_loader(this)
     ! -- allocate and set loader
     if (this%readasarrays) then
       allocate (grid_loader)
-      this%block_loader => grid_loader
+      this%rp_loader => grid_loader
     else
       allocate (list_loader)
-      this%block_loader => list_loader
+      this%rp_loader => list_loader
     end if
     !
     ! -- initialize loader
-    call this%block_loader%init(this%mf6_input, &
-                                this%modelname, &
-                                this%modelfname, &
-                                this%sourcename, &
-                                this%iperblock, &
-                                this%iout)
+    call this%rp_loader%init(this%mf6_input, &
+                             this%modelname, &
+                             this%modelfname, &
+                             this%sourcename, &
+                             this%iperblock, &
+                             this%iout)
     !
     ! -- return
     return
@@ -396,8 +402,8 @@ subroutine dynamic_destroy(this)
     class(Mf6FileDynamicPkgLoadType), intent(inout) :: this
     !
     ! -- deallocate loader
-    call this%block_loader%destroy()
-    deallocate (this%block_loader)
+    call this%rp_loader%destroy()
+    deallocate (this%rp_loader)
     !
     ! -- deallocate parser
     call this%parser%clear()
diff --git a/src/Utilities/Idm/mf6blockfile/StressGridInput.f90 b/src/Utilities/Idm/mf6blockfile/StressGridInput.f90
index 0a65f59995c..e20d8a22040 100644
--- a/src/Utilities/Idm/mf6blockfile/StressGridInput.f90
+++ b/src/Utilities/Idm/mf6blockfile/StressGridInput.f90
@@ -30,16 +30,12 @@ module StressGridInputModule
   !<
   type, extends(AsciiDynamicPkgLoadBaseType) :: StressGridInputType
     integer(I4B) :: tas_active !< Are TAS6 inputs defined
-    integer(I4B) :: nparam !< number of dynamic parameters other than AUX
     type(CharacterStringType), dimension(:), contiguous, &
-      pointer :: aux_tasnames => null() !< array of AUXVAR TAS names
+      pointer :: aux_tasnames !< array of AUXVAR TAS names
     type(CharacterStringType), dimension(:), contiguous, &
-      pointer :: param_tasnames => null() !< array of dynamic param TAS names
-    character(len=LENVARNAME), dimension(:), &
-      allocatable :: param_names !< dynamic param names
+      pointer :: param_tasnames !< array of dynamic param TAS names
     type(ReadStateVarType), dimension(:), allocatable :: param_reads !< read states for current load
-    type(TimeArraySeriesManagerType), pointer :: tasmanager => null() !< TAS manager object
-    type(BoundInputContextType) :: bndctx !< boundary package input context
+    type(TimeArraySeriesManagerType), pointer :: tasmanager !< TAS manager
   contains
     procedure :: init => ingrid_init
     procedure :: df => ingrid_df
@@ -73,6 +69,8 @@ subroutine ingrid_init(this, mf6_input, modelname, modelfname, &
     call this%DynamicPkgLoadType%init(mf6_input, modelname, modelfname, &
                                       source, iperblock, iout)
     ! -- initialize
+    nullify (this%aux_tasnames)
+    nullify (this%param_tasnames)
     this%tas_active = 0
     this%nparam = 0
     this%iout = iout
diff --git a/src/Utilities/Idm/mf6blockfile/StressListInput.f90 b/src/Utilities/Idm/mf6blockfile/StressListInput.f90
index ae7778e908b..2a26905ea76 100644
--- a/src/Utilities/Idm/mf6blockfile/StressListInput.f90
+++ b/src/Utilities/Idm/mf6blockfile/StressListInput.f90
@@ -32,12 +32,9 @@ module StressListInputModule
     integer(I4B) :: ts_active
     integer(I4B) :: ibinary
     integer(I4B) :: oc_inunit
-    integer(I4B) :: ncol
     integer(I4B) :: iboundname
-    character(len=LENVARNAME), dimension(:), allocatable :: cols
-    type(TimeSeriesManagerType), pointer :: tsmanager => null()
+    type(TimeSeriesManagerType), pointer :: tsmanager
     type(StructArrayType), pointer :: structarray
-    type(BoundInputContextType) :: bndctx
   contains
     procedure :: init => inlist_init
     procedure :: df => inlist_df
@@ -99,7 +96,7 @@ subroutine inlist_init(this, mf6_input, modelname, modelfname, &
     call this%bndctx%init(mf6_input, .false.)
     !
     ! -- set SA cols in scope for list input
-    call this%bndctx%filtered_params(this%cols, this%ncol)
+    call this%bndctx%filtered_params(this%param_names, this%nparam)
     !
     ! -- construct and set up the struct array object
     call this%create_structarray()
@@ -180,7 +177,7 @@ subroutine inlist_destroy(this)
     ! -- modules
     class(StressListInputType), intent(inout) :: this !< StressListInputType
     !
-    deallocate (this%cols)
+    deallocate (this%param_names)
     deallocate (this%tsmanager)
     call destructStructArray(this%structarray)
     call this%bndctx%destroy()
@@ -211,16 +208,16 @@ subroutine inlist_ts_link(this, structvector, ts_strloc)
     type(StructVectorType), pointer, intent(in) :: structvector
     type(TSStringLocType), pointer, intent(in) :: ts_strloc
     ! -- locals
-    real(DP), pointer :: bndElem => null()
-    type(TimeSeriesLinkType), pointer :: tsLinkBnd => null()
-    type(TimeSeriesLinkType), pointer :: tsLinkAux => null()
+    real(DP), pointer :: bndElem
+    type(TimeSeriesLinkType), pointer :: tsLinkBnd
+    type(TimeSeriesLinkType), pointer :: tsLinkAux
     type(StructVectorType), pointer :: sv_bound
     character(len=LENBOUNDNAME) :: boundname
     !
     select case (structvector%memtype)
     case (2)
       !
-      tsLinkBnd => NULL()
+      nullify (tsLinkBnd)
       !
       ! -- set bound element
       bndElem => structvector%dbl1d(ts_strloc%row)
@@ -250,7 +247,7 @@ subroutine inlist_ts_link(this, structvector, ts_strloc)
       !
     case (6)
       !
-      tsLinkAux => NULL()
+      nullify (tsLinkAux)
       !
       ! -- set bound element
       bndElem => structvector%dbl2d(ts_strloc%col, ts_strloc%row)
@@ -325,18 +322,18 @@ subroutine create_structarray(this)
     integer(I4B) :: icol
     !
     ! -- construct and set up the struct array object
-    this%structarray => constructStructArray(this%ncol, this%bndctx%maxbound, &
+    this%structarray => constructStructArray(this%nparam, this%bndctx%maxbound, &
                                              0, this%mf6_input%mempath, &
                                              this%mf6_input%component_mempath)
     !
     ! -- set up struct array
-    do icol = 1, this%ncol
+    do icol = 1, this%nparam
       !
       idt => get_param_definition_type(this%mf6_input%param_dfns, &
                                        this%mf6_input%component_type, &
                                        this%mf6_input%subcomponent_type, &
                                        'PERIOD', &
-                                       this%cols(icol), this%sourcename)
+                                       this%param_names(icol), this%sourcename)
       !
       ! -- allocate variable in memory manager
       call this%structarray%mem_create_vector(icol, idt)
diff --git a/src/Utilities/Idm/netcdf/IdmNetCDFFile.f90 b/src/Utilities/Idm/netcdf/IdmNetCDFFile.f90
index 4f48fb19a3a..fc0d6377db4 100644
--- a/src/Utilities/Idm/netcdf/IdmNetCDFFile.f90
+++ b/src/Utilities/Idm/netcdf/IdmNetCDFFile.f90
@@ -24,12 +24,19 @@ module IdmNetCDFFileModule
   public :: open_ncfile
   public :: NC4StaticPkgLoadType
 
-  !> @brief base abstract type for netcdf source dynamic load
+  !> @brief base abstract type for netcdf dynamic loader
   !!
   !<
   type, abstract, extends(DynamicPkgLoadType) :: NCDynamicPkgLoadBaseType
+    integer(I4B) :: ncid
+    integer(I4B) :: iiper
+    integer(I4B) :: nparam
+    character(len=LENVARNAME), dimension(:), &
+      allocatable :: param_names
+    type(BoundInputContextType) :: bndctx
   contains
     procedure(nc_period_load_if), deferred :: rp
+    procedure :: validate
   end type NCDynamicPkgLoadBaseType
 
   abstract interface
@@ -41,66 +48,58 @@ subroutine nc_period_load_if(this, ncid, ncpkg)
     end subroutine
   end interface
 
+  !> @brief NetCDF4 file static loader type
+  !<
   type, extends(StaticPkgLoadBaseType) :: NC4StaticPkgLoadType
     integer(I4B) :: ncid
-    type(NC4ModelPackageInputType), pointer :: ncpkg => null()
+    type(NC4ModelPackageInputType), pointer :: ncpkg
   contains
     procedure :: init => static_init
     procedure :: load => static_load
+    procedure :: destroy => static_destroy
   end type NC4StaticPkgLoadType
 
+  !> @brief NetCDF4 file dynamic loader type
+  !<
   type, extends(DynamicPkgLoadBaseType) :: NC4DynamicPkgLoadType
-    integer(I4B), pointer :: iper => null()
-    integer(I4B), pointer :: ionper => null()
+    integer(I4B), pointer :: iper
+    integer(I4B), pointer :: ionper
     integer(I4B) :: iiper
     integer(I4B) :: ncid
-    type(NC4ModelPackageInputType), pointer :: ncpkg => null()
-    class(NCDynamicPkgLoadBaseType), pointer :: loader => null()
+    type(NC4ModelPackageInputType), pointer :: ncpkg
+    class(NCDynamicPkgLoadBaseType), pointer :: rp_loader
   contains
     procedure :: init => dynamic_init
     procedure :: set => dynamic_set
     procedure :: df => dynamic_df
-    procedure :: rp => dynamic_load
+    procedure :: rp => dynamic_rp
     procedure :: create_loader => dynamic_create_loader
     procedure :: destroy => dynamic_destroy
   end type NC4DynamicPkgLoadType
 
-  !> @brief NetCDF list based dynamic loader type
+  !> @brief NetCDF4 list based dynamic loader type
   !<
   type, extends(NCDynamicPkgLoadBaseType) :: NCListInputType
-    integer(I4B) :: ncid
-    integer(I4B) :: iiper
-    integer(I4B) :: nparam
-    character(len=LENVARNAME), dimension(:), &
-      allocatable :: param_names
-    type(BoundInputContextType) :: bndctx
   contains
     procedure :: init => inlist_init
     procedure :: rp => inlist_rp
-    procedure :: validate => inlist_validate
     procedure :: destroy => inlist_destroy
   end type NCListInputType
 
-  !> @brief NetCDF array based dynamic loader type
+  !> @brief NetCDF4 array based dynamic loader type
   !<
   type, extends(NCDynamicPkgLoadBaseType) :: NCGridInputType
-    integer(I4B) :: ncid
-    integer(I4B) :: iiper
-    integer(I4B) :: nparam !< number of in scope dynamic parameters
-    character(len=LENVARNAME), dimension(:), &
-      allocatable :: param_names !< dynamic param names
     type(ReadStateVarType), dimension(:), allocatable :: param_reads !< read states for current load
-    type(BoundInputContextType) :: bndctx !< boundary package input context
   contains
     procedure :: init => ingrid_init
-    procedure :: alloc => ingrid_alloc
     procedure :: rp => ingrid_rp
-    procedure :: validate => ingrid_validate
     procedure :: destroy => ingrid_destroy
   end type NCGridInputType
 
 contains
 
+  !> @brief static loader init
+  !<
   subroutine static_init(this, mf6_input, modelname, modelfname, source)
     use InputModelContextModule, only: GetModelNC4Context
     class(NC4StaticPkgLoadType), intent(inout) :: this
@@ -110,6 +109,9 @@ subroutine static_init(this, mf6_input, modelname, modelfname, source)
     character(len=*), intent(in) :: source
     type(NC4ModelInputsType), pointer :: nc4_context
     !
+    ! -- initialize
+    nullify (this%ncpkg)
+    !
     call this%StaticPkgLoadType%init(mf6_input, modelname, modelfname, source)
     !
     ! -- set context from input file
@@ -126,15 +128,18 @@ subroutine static_init(this, mf6_input, modelname, modelfname, source)
     return
   end subroutine static_init
 
-  function static_load(this, iout) result(period_loader)
+  !> @brief load routine for static loader
+  !<
+  function static_load(this, iout) result(rp_loader)
     use LoadNetCDFDataModule, only: input_load
     class(NC4StaticPkgLoadType), intent(inout) :: this
     integer(I4B), intent(in) :: iout
-    class(DynamicPkgLoadBaseType), pointer :: period_loader
-    class(NC4DynamicPkgLoadType), pointer :: nc4_loader => null()
+    class(DynamicPkgLoadBaseType), pointer :: rp_loader
+    class(NC4DynamicPkgLoadType), pointer :: nc4_loader
     !
     ! -- initialize
-    nullify (period_loader)
+    nullify (rp_loader)
+    nullify (nc4_loader)
     !
     ! -- load model package to input context
     call input_load(this%mf6_input, this%ncpkg, this%ncid, this%sourcename, iout)
@@ -154,7 +159,7 @@ function static_load(this, iout) result(period_loader)
       call nc4_loader%set(this%ncpkg, this%ncid)
       !
       ! -- set returned base pointer
-      period_loader => nc4_loader
+      rp_loader => nc4_loader
       !
     end if
     !
@@ -162,6 +167,17 @@ function static_load(this, iout) result(period_loader)
     return
   end function static_load
 
+  !> @brief static loader destroy
+  !<
+  subroutine static_destroy(this)
+    class(NC4StaticPkgLoadType), intent(inout) :: this
+    !
+    call this%StaticPkgLoadType%destroy()
+    !
+  end subroutine static_destroy
+
+  !> @brief dynamic loader init
+  !<
   subroutine dynamic_init(this, mf6_input, modelname, modelfname, &
                           source, iperblock, iout)
     use MemoryManagerModule, only: mem_allocate
@@ -181,6 +197,8 @@ subroutine dynamic_init(this, mf6_input, modelname, modelfname, &
     call mem_allocate(this%ionper, 'IONPER', this%mf6_input%mempath)
     !
     ! -- initialize package
+    nullify (this%ncpkg)
+    nullify (this%rp_loader)
     this%iper = 0
     this%ionper = 0
     this%iiper = 0
@@ -189,8 +207,12 @@ subroutine dynamic_init(this, mf6_input, modelname, modelfname, &
     return
   end subroutine dynamic_init
 
+  !> @brief dynamic loader set
+  !!
+  !! Set NC4 package context for dynamic loader
+  !!
+  !<
   subroutine dynamic_set(this, ncpkg, ncid)
-    use MemoryManagerModule, only: mem_allocate
     class(NC4DynamicPkgLoadType), intent(inout) :: this
     type(NC4ModelPackageInputType), pointer, intent(in) :: ncpkg
     integer(I4B), intent(in) :: ncid
@@ -214,6 +236,8 @@ subroutine dynamic_set(this, ncpkg, ncid)
     return
   end subroutine dynamic_set
 
+  !> @brief dynamic loader define
+  !<
   subroutine dynamic_df(this)
     use TdisModule, only: nper
     class(NC4DynamicPkgLoadType), intent(inout) :: this
@@ -230,7 +254,9 @@ subroutine dynamic_df(this)
     return
   end subroutine dynamic_df
 
-  subroutine dynamic_load(this)
+  !> @brief dyanamic loader read and prepare
+  !<
+  subroutine dynamic_rp(this)
     use TdisModule, only: kper, nper
     class(NC4DynamicPkgLoadType), intent(inout) :: this
     !
@@ -238,7 +264,7 @@ subroutine dynamic_load(this)
     if (this%ionper /= kper) return
     !
     ! -- package dynamic load
-    call this%loader%rp(this%ncid, this%ncpkg)
+    call this%rp_loader%rp(this%ncid, this%ncpkg)
     !
     ! -- update loaded iper
     this%iper = kper
@@ -253,7 +279,7 @@ subroutine dynamic_load(this)
     !
     ! -- return
     return
-  end subroutine dynamic_load
+  end subroutine dynamic_rp
 
   !> @brief allocate a dynamic loader based on load context
   !<
@@ -266,38 +292,36 @@ subroutine dynamic_create_loader(this)
     ! -- allocate and set loader
     if (this%readasarrays) then
       allocate (grid_loader)
-      this%loader => grid_loader
+      this%rp_loader => grid_loader
     else
       allocate (list_loader)
-      this%loader => list_loader
+      this%rp_loader => list_loader
     end if
     !
     ! -- initialize loader
-    call this%loader%init(this%mf6_input, &
-                          this%modelname, &
-                          this%modelfname, &
-                          this%sourcename, &
-                          this%iperblock, &
-                          this%iout)
+    call this%rp_loader%init(this%mf6_input, &
+                             this%modelname, &
+                             this%modelfname, &
+                             this%sourcename, &
+                             this%iperblock, &
+                             this%iout)
     !
     ! -- validate package netcdf inputs
-    if (this%readasarrays) then
-      call grid_loader%validate(this%ncpkg)
-    else
-      call list_loader%validate(this%ncpkg)
-    end if
+    call this%rp_loader%validate(this%ncpkg)
     !
     ! -- return
     return
   end subroutine dynamic_create_loader
 
+  !> @brief dynamic loader destroy
+  !<
   subroutine dynamic_destroy(this)
     class(NC4DynamicPkgLoadType), intent(inout) :: this
     !
     ! -- destroy and deallocate loader
-    call this%loader%destroy()
-    deallocate (this%loader)
-    nullify (this%loader)
+    call this%rp_loader%destroy()
+    deallocate (this%rp_loader)
+    nullify (this%rp_loader)
     !
     ! -- deallocate input context
     call this%DynamicPkgLoadType%destroy()
@@ -310,7 +334,6 @@ end subroutine dynamic_destroy
   !<
   function open_ncfile(nc_fname, iout) result(ncid)
     ! -- modules
-    use MemoryManagerExtModule, only: mem_set_value
     use LoadNetCDFDataModule, only: nc_fopen
     ! -- dummy
     character(len=*) :: nc_fname
@@ -338,6 +361,56 @@ function open_ncfile(nc_fname, iout) result(ncid)
     return
   end function open_ncfile
 
+  !> @brief dynamic loader validate
+  !<
+  subroutine validate(this, ncpkg)
+    ! -- modules
+    use InputDefinitionModule, only: InputParamDefinitionType
+    use DefinitionSelectModule, only: get_param_definition_type
+    ! -- dummy
+    class(NCDynamicPkgLoadBaseType), intent(inout) :: this
+    type(NC4ModelPackageInputType), pointer, intent(inout) :: ncpkg
+    ! -- local
+    type(InputParamDefinitionType), pointer :: idt
+    integer(I4B) :: iparam, ivar
+    character(len=LINELENGTH) :: tagname, varname
+    logical(LGP) :: found
+    !
+    ! -- verify required package variables are defined
+    do iparam = 1, this%nparam
+      tagname = this%param_names(iparam)
+      !
+      idt => &
+        get_param_definition_type(this%mf6_input%param_dfns, &
+                                  this%mf6_input%component_type, &
+                                  this%mf6_input%subcomponent_type, &
+                                  'PERIOD', tagname, '')
+      !
+      if (idt%required) then
+        found = .false.
+        do ivar = 1, ncpkg%blocklist(this%iperblock)%varnum
+          varname = ncpkg%blocklist(this%iperblock)%varnames(ivar)
+          if (varname == tagname) then
+            found = .true.
+            exit
+          end if
+        end do
+        !
+        if (.not. found) then
+          errmsg = 'Required PERIOD variable not found: "'//trim(tagname)// &
+                   '" for package "'//trim(this%mf6_input%subcomponent_name)//'".'
+          call store_error(errmsg)
+          call store_error_filename(this%sourcename)
+        end if
+      end if
+    end do
+    !
+    ! -- return
+    return
+  end subroutine validate
+
+  !> @brief dynamic list loader init
+  !<
   subroutine inlist_init(this, mf6_input, modelname, modelfname, &
                          source, iperblock, iout)
     ! -- modules
@@ -360,12 +433,16 @@ subroutine inlist_init(this, mf6_input, modelname, modelfname, &
     !
     ! -- allocate bound params
     call this%bndctx%alloc(this%sourcename)
+    !
+    ! -- set in scope param names
     call this%bndctx%filtered_params(this%param_names, this%nparam)
     !
     ! -- return
     return
   end subroutine inlist_init
 
+  !> @brief dynamic list loader read and prepare
+  !<
   subroutine inlist_rp(this, ncid, ncpkg)
     ! -- modules
     use LoadNetCDFDataModule, only: nc4_rp_list
@@ -385,63 +462,26 @@ subroutine inlist_rp(this, ncid, ncpkg)
     return
   end subroutine inlist_rp
 
-  subroutine inlist_validate(this, ncpkg)
+  !> @brief dynamic list loader destroy
+  !<
+  subroutine inlist_destroy(this)
     ! -- modules
-    use MemoryManagerModule, only: mem_setptr
-    use InputDefinitionModule, only: InputParamDefinitionType
-    use DefinitionSelectModule, only: get_param_definition_type
     ! -- dummy
     class(NCListInputType), intent(inout) :: this
-    type(NC4ModelPackageInputType), pointer, intent(inout) :: ncpkg
-    ! -- local
-    type(InputParamDefinitionType), pointer :: idt
-    integer(I4B) :: iparam, ivar
-    character(len=LINELENGTH) :: tagname, varname
-    logical(LGP) :: found
     !
-    ! -- verify required package variables are defined
-    do iparam = 1, this%nparam
-      tagname = this%param_names(iparam)
-      !
-      idt => &
-        get_param_definition_type(this%mf6_input%param_dfns, &
-                                  this%mf6_input%component_type, &
-                                  this%mf6_input%subcomponent_type, &
-                                  'PERIOD', tagname, '')
-      !
-      if (idt%required) then
-        found = .false.
-        do ivar = 1, ncpkg%blocklist(this%iperblock)%varnum
-          varname = ncpkg%blocklist(this%iperblock)%varnames(ivar)
-          if (varname == tagname) then
-            found = .true.
-            exit
-          end if
-        end do
-        !
-        if (.not. found) then
-          errmsg = 'Required PERIOD package variable not found => '//trim(tagname)
-          call store_error(errmsg)
-          call store_error_filename(this%sourcename)
-        end if
-      end if
-    end do
+    if (allocated(this%param_names)) deallocate (this%param_names)
+    call this%bndctx%destroy()
     !
     ! -- return
     return
-  end subroutine inlist_validate
-
-  subroutine inlist_destroy(this)
-    ! -- modules
-    ! -- dummy
-    class(NCListInputType), intent(inout) :: this
-    if (allocated(this%param_names)) deallocate (this%param_names)
-    call this%bndctx%destroy()
   end subroutine inlist_destroy
 
+  !> @brief dynamic grid loader init
+  !<
   subroutine ingrid_init(this, mf6_input, modelname, modelfname, &
                          source, iperblock, iout)
     ! -- modules
+    use MemoryManagerModule, only: mem_setptr
     ! -- dummy
     class(NCGridInputType), intent(inout) :: this
     type(ModflowInputType), intent(in) :: mf6_input
@@ -450,6 +490,10 @@ subroutine ingrid_init(this, mf6_input, modelname, modelfname, &
     character(len=*), intent(in) :: source
     integer(I4B), intent(in) :: iperblock
     integer(I4B), intent(in) :: iout
+    ! -- local
+    character(len=LENVARNAME) :: rs_varname
+    integer(I4B), pointer :: intvar
+    integer(I4B) :: iparam
     !
     ! -- initialize context
     call this%DynamicPkgLoadType%init(mf6_input, modelname, modelfname, &
@@ -457,25 +501,10 @@ subroutine ingrid_init(this, mf6_input, modelname, modelfname, &
     !
     this%iiper = 0
     !
+    ! -- initialize context
     call this%bndctx%init(this%mf6_input, .true.)
     !
     ! -- allocate bound params
-    call this%alloc()
-    !
-    ! -- return
-    return
-  end subroutine ingrid_init
-
-  subroutine ingrid_alloc(this)
-    ! -- modules
-    use MemoryManagerModule, only: mem_setptr
-    ! -- dummy
-    class(NCGridInputType), intent(inout) :: this !< StressGridInputType
-    character(len=LENVARNAME) :: rs_varname
-    integer(I4B), pointer :: intvar
-    integer(I4B) :: iparam
-    !
-    ! -- allocate period dfn params
     call this%bndctx%alloc(this%sourcename)
     !
     ! -- set in scope param names
@@ -495,8 +524,10 @@ subroutine ingrid_alloc(this)
     !
     ! -- return
     return
-  end subroutine ingrid_alloc
+  end subroutine ingrid_init
 
+  !> @brief dynamic grid loader read and prepare
+  !<
   subroutine ingrid_rp(this, ncid, ncpkg)
     ! -- modules
     use LoadNetCDFDataModule, only: nc4_rp_array
@@ -523,52 +554,8 @@ subroutine ingrid_rp(this, ncid, ncpkg)
     return
   end subroutine ingrid_rp
 
-  subroutine ingrid_validate(this, ncpkg)
-    ! -- modules
-    use InputDefinitionModule, only: InputParamDefinitionType
-    use DefinitionSelectModule, only: get_param_definition_type
-    ! -- dummy
-    class(NCGridInputType), intent(inout) :: this
-    type(NC4ModelPackageInputType), pointer, intent(inout) :: ncpkg
-    ! -- local
-    type(InputParamDefinitionType), pointer :: idt
-    character(len=LINELENGTH) :: tagname, varname
-    integer(I4B) :: iparam, ivar
-    logical(LGP) :: found
-    !
-    do iparam = 1, this%nparam
-      tagname = this%param_names(iparam)
-      !
-      idt => &
-        get_param_definition_type(this%mf6_input%param_dfns, &
-                                  this%mf6_input%component_type, &
-                                  this%mf6_input%subcomponent_type, &
-                                  'PERIOD', tagname, '')
-      !
-      if (idt%required) then
-        found = .false.
-        do ivar = 1, ncpkg%blocklist(this%iperblock)%varnum
-          varname = ncpkg%blocklist(this%iperblock)%varnames(ivar)
-          if (varname == tagname) then
-            found = .true.
-            exit
-          end if
-        end do
-        !
-        if (.not. found) then
-          errmsg = 'Required PERIOD variable not found: "'//trim(tagname)// &
-                   '" for package "'//trim(this%mf6_input%subcomponent_name)//'".'
-          call store_error(errmsg)
-          call store_error_filename(this%sourcename)
-        end if
-      end if
-      !
-    end do
-    !
-    ! -- return
-    return
-  end subroutine ingrid_validate
-
+  !> @brief dynamic grid loader destroy
+  !<
   subroutine ingrid_destroy(this)
     ! -- modules
     ! -- dummy