The purpose of this chapter is to protect critical aquifer recharge areas from degradation or depletion resulting from new or changed land use activities. Due to the exceptional susceptibility and vulnerability of groundwater underlying aquifer recharge areas to contamination and the importance of such groundwater as sources of public water supply, it is the intent of this chapter to safeguard groundwater resources and wellhead protection areas by mitigating or precluding future discharges of any contaminant from new land use activities.
(Ord. 17-513 § 3 (Exh. A))
A. 
General. Critical aquifer recharge areas are areas that have a critical recharging effect on groundwater used for potable water supplies and/or that demonstrate a high level of susceptibility or vulnerability to groundwater contamination from land use activities. These areas include the following:
1. 
Aquifer recharge areas, which are the boundaries of the two highest DRASTIC zones that are rated 180 and above on the DRASTIC index range, as identified in Map of Groundwater Pollution Potential, Edgewood, Washington, National Water Well Association, U.S. Environmental Protection Agency (EPA); and
2. 
Wellhead protection areas, as defined in Chapter 14.20 EMC.
(Ord. 17-513 § 3 (Exh. A); Ord. 25-0695, 12/23/2025)
A. 
General Requirements.
1. 
The city’s Critical Area GIS database provides an indication of where critical aquifer recharge areas are located within the city. This database utilizes the resources identified in EMC § 14.60.020 and is periodically updated as new information becomes available.
2. 
The department will complete a review of the city’s Critical Area GIS database for any development proposal to determine whether the proposed project area for a regulated activity falls within a critical aquifer recharge area.
3. 
Any regulated activity located within critical aquifer recharge areas shall comply with the standards set forth in this chapter.
4. 
Any hazardous uses, as detailed in EMC § 14.60.040D, shall require the submittal of a hydrogeologic assessment, as set forth in EMC § 14.60.050. Other uses do not require the submittal of a hydrogeologic assessment.
5. 
For the purposes of regulating this chapter, “director” means the Public Works Director or their designee.
B. 
Underground Storage Tank (UST) Permits. In addition to the requirements set forth in this title, the following authorities regulate the installation, repair, replacement, or removal of any UST:
1. 
The city’s Building and Fire Official regulates and authorizes permits for all USTs, and hazardous aboveground storage tanks, pursuant to the International Fire Code.
2. 
The Washington State Department of Ecology regulates and authorizes permits for all USTs (Chapter 173-360 WAC).[1]
[1]
Editor's Note: Chapter 173-360 WAC was repealed by WSR 18-15-083 (Order 16-02), filed 7/18/18, effective 10/1/18. See now Chapter 173-360A WAC.
3. 
The TPCHD regulates and authorizes permits for the removal of any UST (Pierce County Code, Chapter 8.34, as adopted by reference under Chapter 8.05 EMC).
(Ord. 17-513 § 3 (Exh. A); Ord. 25-0695, 12/23/2025)
A. 
Exemptions. In addition to the general exemptions listed in EMC § 14.30.030, the following uses or activities are exempt from the requirements of this chapter:
1. 
Sanitary sewer lines and their appurtenances; and
2. 
Individual on-site domestic septic systems or community septic systems releasing less than 14,500 gallons of effluent per day, subject to TPCHD permit requirements.
B. 
Prohibited Uses. Because of high potential for contamination, and low potential for remediation of ground waters used as potable water sources, the following uses of land shall be prohibited within critical aquifer recharge areas:
1. 
Landfills (other than inert and demolition landfills), including hazardous and dangerous waste.
2. 
Underground injection wells (UIC's), except those classes allowed pursuant to Chapter 173-218 WAC for surface water infiltration, remediation of groundwater contamination or aquifer enhancement subject to this Chapter and when permitted by the Washington State Department of Ecology and other applicable permitting authorities (the city, water purveyor, etc.).
3. 
Metals mining.
4. 
Wood treatment facilities.
5. 
Storage, transfer, processing, or disposal of radioactive substances.
6. 
Pesticide/fertilizer manufacturing facilities.
7. 
Storage of more than 70,000 gallons of liquid petroleum or other hazardous substances.
8. 
Other uses or activities determined by the department have a significant impact on groundwater.
C. 
Agricultural Activities. New agricultural activities that do not involve hazardous substance handling or application are allowed within an aquifer recharge or wellhead protection area provided that the criteria in subsection G of this section are met.
D. 
The following hazardous land uses may only be permitted after review and approval of a hydrogeological assessment demonstrating compliance with this section. The hydrogeologic assessment shall comply with EMC § 14.60.050 and will be reviewed by the department and sent to TPCHD for concurrence.
1. 
Animal containment areas;
2. 
Automobile washing facilities;
3. 
Below-ground storage tanks (UST's);
4. 
Hazardous substance processing or handling facilities;
5. 
Hazardous waste treatment, storage, or disposal facilities;
6. 
Inert and demolition waste landfills;
7. 
Significant diversion, alteration or reduction to the flow of ground water, or the impact on a regulated stream base flows or ability in sustaining regulated wetlands; and
8. 
Facilities with the potential to generate hazardous waste, including, but not limited to, boat repair facilities, biological research facilities, dry cleaners, furniture stripping, motor vehicle service garages, photographic processing, and printing shops.
E. 
General. All regulated activities that are not exempt or prohibited under the provisions of this chapter shall ensure sufficient groundwater recharge. In order to achieve sufficient groundwater recharge, the applicant shall comply with the city's adopted stormwater manual, Chapter 13.05 EMC, and demonstrate to the director that the total post-development infiltration rate for the project area will be equal to or better than the predevelopment rate.
F. 
The proposed land use and development shall comply with the critical area protective measure provisions contained in EMC § 14.10.070 unless the department waives these measures as deemed appropriate by the director and can be shown to meet the requirements associated with BAS.
G. 
Protection Standards – Nonhazardous Uses. Subdivision of land as defined in EMC Title 16, multi-family, commercial, and industrial uses or development that do not include or involve hazardous substance processing or handling in critical aquifer recharge areas are allowed subject to the following standards:
1. 
The land use and development complies with subsection D of this section, above.
2. 
Floor drains shall not be allowed to drain to the stormwater system and must be designed and installed to meet the Uniform Plumbing Code (UPC), as adopted in Title 15 EMC.
3. 
If any roof venting carries a contaminant, then the portion of the roof draining from this area must go through pretreatment pursuant to the UPC, as adopted in Title 15 EMC.
4. 
All nonresidential vehicle washing must be self-contained or be discharged to a sanitary sewer system, if approved by the sewer utility, and is subject to the UPC, as adopted in Title 15 EMC.
5. 
Application of household pesticides, herbicides, and fertilizers shall not exceed times and rates specified on the packaging.
6. 
On-site and off-site septic systems shall demonstrate compliance with TPCHD requirements.
7. 
Additional protective measures may be required if deemed necessary by the department to protect public health or safety.
H. 
Protection Standards – General Hazardous Uses. The land use and development shall demonstrate that the proposed activity will not cause contaminants to enter the aquifer and that the proposed activity will not adversely affect the recharging of the aquifer and complies with all federal and state laws. Based on the available information, the director shall have discretion to impose conditions designed to prevent degradation of ground water quality or quantity. Such conditions may include a hydrologic site evaluation, determination of background water quality, quantity, and ground water levels prior to approval and development of ground water quality and/or quantity management plans. All conditions shall be based on all known, available, and reasonable methods of prevention, control, and treatment.
I. 
Protection Standards – Hazardous Uses – Storage Tanks. In addition to the requirement to submit a hydrogeologic assessment, the following standards apply to storage tanks in critical aquifer recharge areas:
1. 
Underground. All new UST's used or to be used for the underground storage of hazardous substances or hazardous wastes shall be designed and constructed so as to:
a. 
Prevent releases due to corrosion or structural failure for the operational life of the tank;
b. 
Be protected against corrosion, constructed of noncorrosive material, steel clad with a noncorrosive material, or designed to include a secondary containment system to prevent the release or threatened release of any stored substance;
c. 
Use material in the construction or lining of the tank which is compatible with the substance to be stored; and
d. 
The installation of any UST shall also be subject to other state and local permit requirements, pursuant to EMC § 14.60.030B.
2. 
Aboveground.
a. 
No new above-ground storage facility or part thereof shall be fabricated, constructed, installed, used, or maintained in any manner which may allow the release of a hazardous substance to the ground, groundwater, or surface water within any critical aquifer recharge areas.
b. 
A new above-ground tank that will contain a hazardous substance will require both a double-walled tank and a secondary containment system separate from the tank that will hold 110 percent of the tank's capacity. The secondary containment system or dike system must be designed and installed/constructed with impervious materials to contain all of the material stored in the tank(s).
J. 
Protection Standards – Hazardous Uses – Vehicle Repair and Servicing.
1. 
Vehicle repair and servicing must be conducted over impermeable pads and within a covered structure capable of withstanding normally expected weather conditions. Chemicals used in the process of vehicle repair and servicing must be stored in a manner that protects them from weather and provides containment should any leaks occur.
2. 
No dry wells shall be allowed in critical aquifer recharge areas on sites used for vehicle repair and servicing. Dry wells existing on the site prior to facility establishment must be abandoned using techniques approved by the Washington State Department of Ecology prior to commencement of the proposed activity.
(Ord. 17-513 § 3 (Exh. A); Ord. 24-660 §§ 11 – 13 (Exh. B); Ord. 25-0695, 12/23/2025)
A. 
Hydrogeologic assessment shall, at a minimum, include the following:
1. 
Hydrological assessment shall include the general critical report requirements pursuant to EMC § 14.10.080.
2. 
Prepared, signed, and dated by a geotechnical professional.
3. 
Include, but not limited to:
a. 
Information sources;
b. 
Geologic setting — includes well logs or borings used to identify information;
c. 
Background water quality;
d. 
Groundwater elevations;
e. 
Location and depth to perched water tables;
f. 
Recharge potential of a facility site, i.e., the permeability and transmissivity;
g. 
Groundwater flow direction and gradient;
h. 
Currently available data on wells located within one-quarter mile of the site;
i. 
Currently available data on any spring within one-quarter mile of the site;
j. 
Surface water location and recharge potential;
k. 
Water source supply to a facility, e.g., a 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 Director.
(Ord. 25-0695, 12/23/2025)