Areas Susceptible to Groundwater Contamination

Description | Contacts | Attribute Information | Constraints

Description

Layer name: ASGWC
Subject category: enviro
Title: Areas Susceptible to Groundwater Contamination
Feature Count: 0
Feature Type: Polygon
Abstract: Areas susceptible to groundwater contamination
Purpose: This dataset was created to fulfill a requirement of the Growth Management Act: analysze and protect remaining areas of high aquifer susceptibility ot groundwater contamination.
Status: Complete
Updated: As needed
Time period of content: (single date,as YYYYMMDD)::
Time period of content: (date range, as YYYYMMDD):: -
Spatial reference: WA State Plane North
FGDC Documentation: Classic or FAQ
Open Data Availability: Yes
Place Keywords: Pacific NW, Washington state, King County, WA,
Theme Keywords: groundwater, natural resources, enviro,
Lineage: Available
Supplemental Information: The ASGWC data history: This data set represents the joining of 9 separate analyses for 9 different study areas. In most cases, surficial geology, soils and depth to groundwater were combined in a matrix to determine final susceptibility. SOURCES: Vashon - Maury Island : used new geology from U. of Wa. for PType, (WHPA's, DTW, to update ASGWC susceptibility data July 2007. New susceptibility data from U. of Wa. added for parts of Issaquah and Redmond/Bear Creek data updated Feb. 2008. Schema changes Feb. 2008, added "D_GW"; "RECHARGE" name changed to " SUSCEPT"; "RCH_SUM" changed to "SUSCP_SUM". REDMOND/BEAR CREEK GWMA - EMCON NW Date: 01/01/1992 Scale: Unknown VASHON GWMA - GERACHTY AND MILLER Date: 01/01/1993 Scale: Unknown Date: 01/01/1993 Scale: Unknown SOUTH KING GWMA - ECOMOMIC AND ENGINEERING SERVICES, INC. Date: 01/01/1991 Scale: Unknown EAST KING GWMA - US GEO. SURVEY, TACOMA Date: 01/01/1993 Scale: Unknown LOWER CEDAR S.A. - EMCON NW Date: 01/01/1993 Scale: Unknown ENUMCLAW, HWOLLYWOOD HILLS, AND S. BELLEVUE - KC STAFF(DDES) Date: 01/01/1994 Scale: Unknown MANUSCRIPTION: For all consultant work: please consult the studies. King County Staff interpreted geology, soils, and well log maps for their contribution to the process. List of steps: Interpretation - Looking at USGS Geology and SCS soils maps, they were interpreted for H-M-L as regards recharge. Interpretation - Well log data was plotted based on lat-long coords. Depth to groundwater was determined for each well. Polygons were then drawn for H-M-L D. to groundwater AUTOMATION: (King Co. Staff work only) 3 layers (GEO., soils,depth to GW) were over lanin. A matrix was used to determine resultant recharge in each resulting polygon. QUALITY ASSURANCE: March 2008, digitizing irregularities and null values have been noted by DNRP/WLRD/STS/WQQ - Hydrologic Services Group and KC GIS data steward. These irregularities will be addressed in future updates to ASGWC. The total area increased because the RBC has a greater mapped area than the previous ASGWC map extent. The ASGWC data history: This data set represents the joining of 9 separate analyses for 9 different study areas. In most cases, surficial geology, soils and depth to groundwater were combined in a matrix to determine final susceptibility. SOURCES: Vashon - Maury Island : used new geology from U. of Wa. for PType, (WHPA's, DTW, to update ASGWC susceptibility data July 2007. New susceptibility data from U. of Wa. added for parts of Issaquah and Redmond/Bear Creek data updated Feb. 2008. Schema changes Feb. 2008, added "D_GW"; "RECHARGE" name changed to " SUSCEPT"; "RCH_SUM" changed to "SUSCP_SUM". REDMOND/BEAR CREEK GWMA - EMCON NW Date: 01/01/1992 Scale: Unknown VASHON GWMA - GERACHTY AND MILLER Date: 01/01/1993 Scale: Unknown Date: 01/01/1993 Scale: Unknown SOUTH KING GWMA - ECOMOMIC AND ENGINEERING SERVICES, INC. Date: 01/01/1991 Scale: Unknown EAST KING GWMA - US GEO. SURVEY, TACOMA Date: 01/01/1993 Scale: Unknown LOWER CEDAR S.A. - EMCON NW Date: 01/01/1993 Scale: Unknown ENUMCLAW, HWOLLYWOOD HILLS, AND S. BELLEVUE - KC STAFF(DDES) Date: 01/01/1994 Scale: Unknown MANUSCRIPTION: For all consultant work: please consult the studies. King County Staff interpreted geology, soils, and well log maps for their contribution to the process. List of steps: Interpretation - Looking at USGS Geology and SCS soils maps, they were interpreted for H-M-L as regards recharge. Interpretation - Well log data was plotted based on lat-long coords. Depth to groundwater was determined for each well. Polygons were then drawn for H-M-L D. to groundwater AUTOMATION: (King Co. Staff work only) 3 layers (GEO., soils,depth to GW) were over lanin. A matrix was used to determine resultant recharge in each resulting polygon. QUALITY ASSURANCE: March 2008, digitizing irregularities and null values have been noted by DNRP/WLRD/STS/WQQ - Hydrologic Services Group and KC GIS data steward. These irregularities will be addressed in future updates to ASGWC. The total area increased because the RBC has a greater mapped area than the previous ASGWC map extent.

Contacts

Maintained by:
King County Dept. of Natural Resources and Parks, Water and Lands Resources Division
Primary: Ken Rauscher, Senior GIS Analyst, 206-296-1922
(How to e-mail a County contact)
Secondary: KCGIS Center; giscenter@kingcounty.gov. This mailbox is monitored during business hours.

Attribute Information

Item

Description

Domain

_GEOL_TYPE

_Geology type

Qw	Wetland Deposits, peat and alluvium, poorly drained and intermittently we annually Grades into unit Qyal
Qvt	Till-Compact diamict containing subrounded to well-rounded clasts, glacially transported and deposited. Includes minor stratified fluvial deposits. Generally forms an undulating surface a few meters to a few tens of meters thick. In ice-marginal areas and where covered by thin layer of recessional outwash, contact with recessional-outwash or ice-contact deposits (Qvr or Qvi) is gradational.
Qvrl	Silt-dominated lowland lacustrine depositis
Qvr	Recessional outwash deposits. Stratified sand and gravel, moderately to well sorted, and well-bedded silty sand to silty clay deposited in proglacial and ice-marginal environments.
Qvlc
Qvi	Ice-contact deposits
Qva	Advance outwash deposits
Qpogf
Qpog
Qpof	coarse-grained deposits -Sedimentary deposits of pre-Olympia interglaciation age (Pleistocene)
Qpft
Qpdc
Qos
Qoal
Qf	Alluvial fan depositis (Holocene)
Qb	Beach deposits (Holocene)-Loose sand deposited by wave action
Qal
af

_POT_G

_1 character code for the susceptibility as defined by geology type (High, Medium & Low)

H	High as defined by geology type
M	Medium as defined by geology type
L	Low as defined by geology type

_POT_G_CD

_number code for the POT_G code (High = 2.0, Medium = 1.00, Low = 0.00)

2.00	High = 2.00
1.00	Medium = 1.00
0.00	Low = 0.00

_GW_DEPTH

_Depth of Groundwater (in feet)

H	High is <25'
M	Medium is in between High and Low
L	Low is >75'

_POT_D

_1 character code for the susceptiblity as defined by depth to groundwater (High, Medium & Low)

H	High = 2.00
M	Medium = 1.00
L	Low = 0.00

_POT_D_CD

_Number code for the POT_D code (Hight = 2.00, Medium = 1.00 or Low = 0.00)

2.00	High = 2.00
1.00	Medium = 1.00
0.00	Low = 0.00

_POT_S

_1 character code for the susceptiblilty as defined by soil type (High, Medium or Low).

H	High = 2.00
M	Medium = 1.00
L	Low = 0.00

_POT_S_CD

_Number code for the POT_S code (Hight = 2.00, Medium = 1.00 or Low = 0.00)

2.00	High = 2.00
1.00	Medium = 1.00
0.00	Low = 0.00

_D_GW

_Range of Ground Water depth.

_SUSCP_SUM

_The total of adding of the three susceptibility categories as follow: POT_G + POT_D + (0.25 * POT_S). The possible range of values for this field is 0.00 to 4.50.

_SUSCEPT

_1 character code for the total susceptibility as defined by SUSCP_SUM (High, Medium or Low)

Constraints

Access: None

Use: King County data are made available with the understanding that they shall be used exclusively by the obtainer or his/her authorized agents. Digital products may not be reproduced or redistributed in any form or by any means without the express written authorization of King County.