23. Airport Zone Volume Two 23.3.7.1. The Council must be notified at least 5 working days prior to the burning activity commencing. 23.3.7.2. The discharge must not occur during the months of May, June, July or August. 23.3.7.3. Any discharges for purposes of training people to put out fires must take place under the control of the NZ Fire Service or any other nationally recognised agency authorised to undertake firefighting research or firefighting activities. 23.3.8. Discharge of contaminants to air from the combustion of fuel (i.e., external combustion). 23.3.8.1. The discharge must not contain more than the following maximum heat output limits: (a) 10MW for natural or liquefied petroleum gas; (b) 40kW for untreated wood; (c) 100kW for coal; (d) 40kW for light fuel oil; (e) 1.0MW for pellet fuel when burnt in a custom designed pellet boiler; (f) 400kW for pellet fuel when burnt in a standard boiler converted for pellet fuel use; (g) 10MW for diesel; (h) 2MW for kerosene. 23.3.8.2. The limits in 23.3.8.1 apply to the total heat output from the site. Where more than one fuel type is used on the site, the combined heat output must not exceed the lowest MW or kW threshold of any of the fuel types used. 23.3.8.3. The fuel must be burned using fuel burning equipment, and the discharge must be from a chimney or exhaust structure designed so that the emission is effectively dispersed upwards. 23.3.8.4. The opacity of the discharge when measured at the point of entry to the atmosphere must not exceed 20%, except that a discharge in excess of this is allowed for a period of not more than 2 minutes continuously, or for an aggregate of 4 minutes, in any 60 minute period. 23.3.8.5. The fuel burning equipment must be maintained in accordance with the manufacturer’s specifications at least once every year by a person competent in the maintenance of that equipment. A log recording all maintenance must be made available to the Council on request. 23.3.8.6. The stack must comply with requirements in Appendix 8 – Schedule 5. 23.3.8.7. Coal must not be burned as a fuel if there are buildings higher than 6m within a 25m radius of the discharge. Fuels other than coal must not be burned if there are buildings higher than 5m within a 25m radius of the discharge. 23.3.8.8. The sulphur content of any coal burnt must be less than 2%. 23.3.9. Discharge of contaminants to air from combustion within a stationary internal combustion engine (i.e., internal combustion). 23.3.9.1. The fuel must be gas, LPG, petrol, diesel, vegetable oils or alcohol. 23 – 8