HomeMy WebLinkAboutSUB201900042 Assessment - Groundwater 2024-04-0504 TIER II GROUNDWATER ASSESSMENT
County of Albemarle
a� Department of Community Development
401 McIntire Road, North Wing
t i Charlottesville, Virginia 22902
�(1it�e 434-296-5832 1 www.albemarle.org/cdd
DATE: 05/09/2019
APPLICATION: SUB 2019-00042
PROJECT NAME: Lots DI-D7 Preliminary
TMP: 04300-00-00-018DO
The pending development on the property affected by the above referenced application number
meets criteria outlined in Albemarle County Code Article IV - Groundwater Assessments to
warrant a Tier 2 Groundwater Assessment. The following assessment uses the best available
sources to outline the various groundwater conditions that could have an impact on this property.
Water Quantity
# of Wells within .5 Miles of Parcel: 15
Range of Depth of those wells: 0.0 to 436.0 feet
Range of Yield of those wells: 0.0 to 30.0 gallons per minute (gpm)
Median Yield for Wells in County: 6.0 gpm
Water Ouality
# of Leaking Underground Storage Tanks (LUSTS) within 2000 Feet of Parcel: 0
# of Superfund sites within .5 miles: 0
# of Landfills within .5 miles: 0
Hydroaraohv
of Parcel that Contains Required Stream Buffers: 8.5%
Watershed of Parcel(Y/N'):
Ivy Creek -Little Ivy Creek (Y) 100.0%
Geology
Bedrock:
Blue Ridge basement complex(Ybg) - porphyroblastic biotite plagioclase augen gneiss 100.0%
Hydrogeologic Units*:
Piedmont Foothills -III 100.0%
If you should have any questions, please contact the Community Development Department at
434-296-5832.
A "Y" indicates that the watershed is a water supply watershed. An "N" means that it is not.
1
*Hydrogeologic Units Defined
Taken from the 1213012003 Albemarle County Hydrogeologic Assessment Phase II -
Groundwater Availability and Sensitivity Assessment with Proposed Groundwater Assessment
Standards. Prepared by ENSAT Corporation, Culpeper, VA.
The process of investigating groundwater availability at the County -wide scale involved identifying distinct
hydrogeologic units and comparing the units based on groundwater availability characteristics for which data
could be obtained. Each hydrogeologic unit shares some common characteristics with regard to geology,
soils, and topography, although there is quite a bit of variability within each unit.
Nine hydrogeologic units were identified across the County, as follows, and as shown on the Albemarle
County Hydrogeologic Unit Map (Figure 2).
1.
2.
Figure 2 - Albemarle County Hydrogeologic Unit Map
Blue Ridge West-IW: This unit lies primarily
on the steep eastern slopes of the Blue Ridge
Mountains and is dominated by the Myersville
and Parker Soils, and to a lesser extent the
Chester. Slopes range from 2-60%. These soils
are residual in nature. The Myersville soils are
derived from weathered volcanic metamorphic
rocks (greenstone) and Parker and Chester soil
series are derived from weathered granite and
granite gneiss. These soils are considered to be
relatively deep and well drained.
Blue Ridge East-IE: The Blue Ridge East unit
overlies volcanic greenstone rock and represents
the eastern limb of the Blue Ridge Anticlinorium.
The area is characterized by the presence of a
prominent ridge and trends generally northeast
within the otherwise rolling pledmont landscape.
Portions of this ridge are known locally as Green
Mountain, Carters Mountain, and the Southwest
Mountains. This area Is dominated by the Rabun
and Myersville soils and to a lesser extent, the
Catoctin. The Rabun soil series is deep and well
drained and like the Myersville soil series is
formed from weathered greenstone. The
Catoctin soil series is considered to be
moderately deep and well drained and is also
formed from weathered greenstone.
Colluvial Fans -II: The Colluvial Fan unit lies at
the base of the eastern slopes of the Blue Ridge
Mountain and is characterized by relatively steep
drainage swales that extend to more gradual sloping conditions. The area includes a series of
intermittent drainages that include ephemeral drainage ways. Many of the intermittent drainages
become perennial streams as this area includes stream bottom valleys. A significant portion of the unit
area consists of transported soils including the Braddock and Thurmont. These soils are formed in
colluvial and alluvial materials found on colluvial fans and terraces and are the product of weathered
granite, granodiorite, granite gneiss, and greenstone. Both of these soil series are deep and well
drained with slopes ranging from 2-25%. Residual soils including the Hayesville and the Chester are
also abundant. These soils are also deep and well drained and are formed on upland slopes from
weathered products of granite and granite gneiss. Slopes of these soils typically range from 2-45%.
Bedrock geology consists largely of metagranitic rock of the Blue Ridge Basement Complex and
metasedimentary, metaconglomerate and phyllite of the Swift Run Formation. The accumulation of
transported soils (colluvial and alluvial) can form "cappings" over residual soils and parent material,
which can add to the overall thickness of the overburden.
4. Piedmont Foothills -III: The Piedmont Foothills unit is characterized by rolling upland to relatively
steep topography. Soils within this area dominated by the Hayesville, Ashe and Chester soil series
which are moderately deep to deep, and generally well drained. These soils are found on the piedmont
upland and foothills of the Blue Ridge Mountain on slopes ranging from 2-45%. These soils are formed