The Georgia Department of Natural Resources has mapped "significant recharge areas" for the State of Georgia. Several recharge areas have been identified in Troup County. Recharge areas are vulnerable to urban development activities as well as agricultural activities. Pesticides, herbicides sprayed on crops, animal waste and septic tank affluence contribute to deterioration in the groundwater quality and can threaten the health of residents relying on well water. Development usually means an increase in the amount of land covered with impervious surfaces. Paving land in recharge areas can alter or impair their recharge characteristics thereby decreasing groundwater supplies. The purpose of the groundwater recharge area protection district is to establish measures to protect Troup County's identified recharge areas from potential sources of contamination by spills, discharges, leaks, impoundment's, application of chemicals, injections and other development pressures.

The following definitions shall apply to the groundwater recharge district:

(a)

Pollution susceptibility means the relative vulnerability of an aquifer to being polluted from spills, discharges, leaks, impoundment, and applications of chemicals, injections and other human activities in the recharge area.

(b)

Pollution susceptibility maps means maps of relative vulnerability to pollution prepared by the Department of Natural Resources, using the DRASTIC methodology. Pollution susceptibility maps categorize the land areas of the state into areas having high, medium and low groundwater pollution potential.

(c)

Recharge area means any portion of the earth's surface, where water infiltrates into the ground to replenish an aquifer.

(d)

Significant recharge areas mean those areas mapped by the Department of Natural Resources in Hydrologic Atlas 18 (1989 edition). Mapping of recharge areas is based on outcrop area, lithology, soil type and thickness, slope, density of lithologic contacts, geologic structure, the presence of karst, and potentiometric surfaces.

This article will create zoning districts to be known as the "groundwater recharge districts," hereinafter referred to as the "districts." The boundary shall be set at places readily identifiable on the groundwater recharge map. The groundwater recharge map overlies the Troup County zoning map, which is hereby incorporated and made a part of this article by referral.

The groundwater recharge area protection map is delineated according to the Georgia Department of Natural Resources' "Significant Recharge Areas, Hydrological Atlas 18 (1989 Edition)" and the Georgia Department of Natural Resources "Pollution Susceptibility Map Hydrological Atlas 20 (1992 Edition)," standards for this district shall comply with the DNR Rule 391-2-02, Criteria for the Protection of Groundwater Recharge Areas.

Unless otherwise noted in the groundwater recharge district regulations, the regulations of the underlying zoning district shall be maintained and not affected.

The following criteria shall apply in significant recharge areas:

(a)

New aboveground chemical or petroleum storage tanks, having a minimum volume of 660 gallons, shall have secondary containment for 110 percent of the volume of such tank or 110 percent of the volume of the largest tank in a cluster of tanks. Such tanks used for agricultural purposes are exempt, provided they comply with all federal requirements.

(b)

New agricultural waste impoundment sites shall be lined if they are within:

(1)

A low pollution susceptibility area and exceed 50 acre feet.

(2)

As a minimum, the liner shall be constructed of compacted clay having a thickness of one-foot and a vertical hydraulic conductivity of less than 5 × 10-7 cm/sec or other criteria established by the U.S. Soil Conservation Service. (The average size of existing agricultural waste impoundment's in Georgia is about 15 acre-feet; sheeps-foot rollers or pans with heavy rubber tires, which are normal equipment for most Georgia earth moving contractors, should be able to compact clay to the recommended vertical hydraulic conductivity.)

(c)

New homes served by septic tank/drainfield systems shall be on lots having the following minimum size limitations as identified on table MT-1 of the Department of Human Resources' Manual for On-Site Sewage Management Systems (hereinafter "DHR table MT-1"):

(1)

One hundred ten percent of the subdivision minimum lot or space size of DHR table MT-1 if they are within a low pollution susceptibility area.

(d)

New mobile home [manufactured home] parks served by septic tank/drainfield systems shall have lots or spaces having the following size limitation as identified on table MT-2 of the Department of Human Resources' Manual for On-Site Sewage Management Systems (hereinafter "DHR table MT-2"):

(1)

One hundred ten percent of the subdivision minimum lot or space size of DHR table MT-2 if they are within a low pollution susceptibility area.

(e)

All multifamily development located within a high pollution susceptibility groundwater recharge area shall be required to have the following minimum lot sizes: where individual on-site sewer systems are installed in conjunction with public water systems the minimum lot size for multifamily structure shall be 10,890 square feet per unit; where individual on-site sewer systems are installed in conjunction with an individual water system the minimum lot size shall be 21,780 square feet per unit. The Troup County health department shall approve all multifamily developments. If there are conflicts between provisions of these regulations, the stricter shall apply.

(f)

If a local government requires a larger lot size than that required by subsection (c) above for homes or by subsection (d) above for mobile homes [manufactured homes], the larger lot size shall be used.

(g)

Troup County at its option may exempt from the requirements of subsection (c) or (d) any lot of record on the date of their adoption of these lot size standards.

(h)

No construction may proceed on a building or mobile home [manufactured home] to be served by a septic tank unless the county health department first approves the proposed septic tank installation as meeting the requirements of the DHR manual and subsections (c), (d), (f), and (g) above.

(i)

New facilities which handle hazardous materials of the types listed in section 312 of the Resource Conservation and Recovery Act of 1976, excluding underground storage tanks, in amounts of 10,000 pounds or more on any one day, shall perform their operations on impervious surfaces and in conformance with any applicable federal spill prevention requirements and any local fire code requirements.