Special use permits
A. An applicant proposing a use specified in the zoning use matrix as requiring a special use permit must apply to the zoning board of review under the provisions of article I, section l.3.F. The applicant for a groundwater protection district special use permit must prove by clear, convincing and scientifically valid evidence that the proposed use will not result in concentrations of pollutants in the groundwater that will adversely affect the groundwater as a source of potable water. After reviewing the application for a groundwater protection district special use permit, the Exeter zoning board shall either:
1. Approve the application;
2. Deny the application;
3. Approve the application with conditions; [or]
4. Request additional information.
B. Before review of a special use permit application, the applicant must show evidence of applicable state approval for storage of hazardous materials and petroleum products and for the disposal of waste products.
C. The applicant for a special use permit shall, at [a] minimum, conform to the following performance and design standards, unless an alternative is proposed that meets the same objective as the standard[s] specified below. The town may specify additional design, construction and operation standards.
D. Performance and design standards:
1. Interior floor drains designed to allow fluid from any interior space to be discharged into or onto the ground shall be prohibited; provided, however, that such interior floor drains may be permitted if designed to empty into an aboveground storage tank capable of completely containing anticipated flows. Such tanks, if provided, shall also be subject to containment provisions of this section.
2. Storage of hazardous materials and petroleum products shall be located within a building unless it is decided that indoor storage will not meet fire safety standards. The indoor storage shall be within a containment structure that meets the following standards:
a. Constructed in a way that prevents the release of hazardous material and petroleum products and constructed of such materials that are impermeable and compatible to the materials being contained;
b. The containment structure shall, at a minimum be designed to contain the following volumes:
i. For aboveground storage tanks, 100 percent of the capacity of the largest tank; [and]
ii. For individual containers, e.g., drums, ten percent of the total volume of the containers or the volume of the largest container.
3. Exterior storage of petroleum products or hazardous materials shall be located in a containment structure that meets the following standards:
a. An impermeable base and surrounding dike. Such base and dike shall be constructed of material that is impermeable and compatible with the material being contained.
b. The containment structure shall, at minimum, be designed to contain the following volumes:
i. For aboveground storage tanks, 100 percent of the capacity of the largest tank; [and]
ii. For individual containers, e.g., drums, 100 percent of the total volume of the containers, or the volume of the largest container.
c. The containment structure shall be protected by a roof and adequate sides to prevent exposure to precipitation.
4. Drums and storage containers shall be fitted with secure lids to prevent spills or leaks; storage as full as possible to prevent vapors and the chance of an explosion; drip pans shall be placed under spigots.
5. Storage areas shall be inspected monthly, and records of such inspections shall be maintained on-site and available for review.
6. Containers and tanks shall be clearly labeled.
7. Hazardous materials generation and storage areas shall be clearly marked.
8. Venting systems for evaporation or other type of discharge to the atmosphere of hazardous materials shall be designed with a recovery system to prevent the release of contaminated condensate or drips.
9. Areas used for loading and transferring hazardous materials and petroleum products shall have an impermeable surface and a dike to contain accidental spills or leaks.
10. Dumpsters used to store solid wastes shall be covered or located within a roofed area and have drain plugs intact.
E. Submission requirements:
1. Submit a groundwater protection plan, including the following sections as applicable:
a. Hazardous materials and petroleum product management. The proper management and housekeeping of hazardous materials and petroleum products shall be clearly outlined in the plan as follows:
i. A complete list and the maximum quantity of all hazardous materials and petroleum products to be handled or stored on the premises at any time;
ii. Evidence of a qualified professional supervision in the design, installation, operation and maintenance of facilities or containers to be used for the handling or storage of hazardous materials and petroleum products;
iii. Measures proposed to protect all hazardous materials and petroleum product storage containers from vandalism, corrosion, leakage or spillage;
iv. Proposed measures to mitigate any potentially adverse impact from hazardous materials or petroleum products on the groundwater;
v. Description of the method by which state and local authorities will be notified in case of an accident or spill of a hazardous material or petroleum product that will have a potentially adverse impact on the environment; [and]
vi. A schedule whereby periodic proof will be submitted to the zoning inspector (additional copies submitted to the conservation commission) that hazardous materials and petroleum products are managed as stated in the groundwater protection plan.
b. Waste management. The groundwater protection plan shall address the following:
i. A description of the waste products generated and the projected average and maximum daily volumes that will be generated;
ii. A description of the system to collect, store, treat (if necessary) and dispose off-site all waste products other than sanitary sewage;
iii. A nutrient loading analysis is required for an individual sewage disposal system proposed to discharge more than 2,000 gallons per day of sanitary sewage;
iv. Evidence of qualified professional supervision in the design, installation, maintenance and operation of the waste management system;
v. Measure proposed to protect the waste management system from vandalism, leakage, spillage or malfunction;
vi. Proposed measures to mitigate any potential adverse impact resulting from the failure of the waste management system;
vii. Description of the method by which state and local authorities will be notified in case of a failure of the waste management system that will potentially have an adverse impact on the environment; [and]
viii. A schedule whereby periodic proof will be submitted of the zoning inspector (additional copies submitted to the conservation commission) that the waste management system is being used and is operating as stated in the groundwater protection plan.
c. A map showing the location of all water bodies, wetlands, storm drains, and public and private wells within 1,000 feet of the property boundary.
d. Any other information the town decides is necessary to evaluate the potential for adverse impacts to groundwater quality.