18E.50.030 Aquifer Recharge and Wellhead Protection Area Review Procedures.
A. General Requirements.
1. The Pierce County Critical Areas Atlas-Aquifer Recharge and Wellhead Protection Area Map provides an indication of where aquifer recharge and wellhead protection areas are located within the County.
2. The Department will complete a review of the Aquifer Recharge Area Map for any development proposal to determine whether the proposed project area for a regulated activity falls within an aquifer recharge or wellhead protection area.
3. When the Department's maps or sources indicate that the proposed project area for a regulated activity is located within an aquifer recharge or wellhead protection area, the Department shall require aquifer recharge and wellhead protection area review as set forth in this Chapter.
4. Any regulated activity located within an aquifer recharge or wellhead protection area shall comply with the standards set forth in PCC 18E.50.040.
5. Any hazardous uses, as defined in PCC 18E.50.040, shall require the submittal of a hydrogeologic assessment, as set forth in PCC 18E.50.030 B. below.
6. The Department may waive some of the critical area protective measure provisions contained in PCC 18E.10.080.
B. Hydrogeologic Assessment.
1. The hydrogeologic assessment shall be prepared under the responsible charge of an appropriately licensed geotechnical professional, and signed, sealed, and dated by an appropriately licensed geotechnical professional.
2. The hydrogeologic assessment shall be submitted in the form of a report detailing the subsurface conditions, the design of a proposed land use action, and the facilities operation which indicates the susceptibility and potential for contamination of groundwater supplies. The hydrogeologic assessment shall, at a minimum, include the following:
a. Information sources;
b. Geologic setting – Include well logs or borings used to identify information;
c. Background water quality;
d. Groundwater elevations;
e. Location/depth to perched water tables;
f. Recharge potential of facility site (permeability/transmissivity);
g. Groundwater flow direction and gradient;
h. Currently available data on wells located within 1/4 mile of the site;
i. Currently available data on any spring within 1/4 mile of the site;
j. Surface water location and recharge potential;
k. Water source supply to facility (e.g., high capacity well);
l. Any sampling schedules necessary;
m. Discussion of the effects of the proposed project on the groundwater resource;
n. Discussion of potential mitigation measures, should it be determined that the proposed project will have an adverse impact on groundwater resources; and
o. Any other information as required by the TPCHD, including information required under Washington Department of Ecology Publication 97-30.
3. The TPCHD shall provide written notice to all Group A water systems in whose wellhead protection area the proposed regulated activity lies. The TPCHD shall consider comments received from the water system(s) when reviewing the hydrogeologic assessment.
4. Uses requiring a hydrogeologic assessment may be conditioned or denied based upon the TPCHD's evaluation of the hydrogeologic assessment. Any project denied a permit based upon the TPCHD's evaluation of the hydrogeologic assessment shall receive a written explanation of the reason(s) for denial and an explanation of standards required, if any, to comply with these regulations.
C. Storage Tank Permits. In addition to the requirements set forth in this Title, the following agencies also have the authority to regulate the installation, repair, replacement, or removal of underground storage tanks:
1. The Pierce County Fire Prevention Bureau regulates and authorizes permits for underground storage tanks, pursuant to the International Fire Code (Article 79) and this Chapter.
2. The Washington Department of Ecology regulates and authorizes permits for underground storage tanks (Chapter 173-360 WAC).
3. The TPCHD regulates and authorizes permits for the removal of underground storage tanks (Chapter 8.34 PCC).