La. Admin. Code tit. 51 § XII-209

Current through Register Vol. 50, No. 11, November 20, 2024

Section XII-209 - Specific Chemicals

A. Chlorine Gas. Chlorinators should be housed in a room separate from but adjacent to the chlorine storage room.

1. Chlorinator rooms should be heated to 60°F, and be protected from excessive heat. Cylinders and gas lines should be protected from temperatures above that of the feed equipment.

2. Both the chlorine gas feed and storage rooms should be located in a corner of the building on the prevailing downwind side of the building and be away from entrances, windows, louvers, walkways, etc.

3. If chlorine gas feed and storage is enclosed, the chlorine gas shall be separated from other operating areas. Both the feed and storage rooms shall be constructed so as to meet the following requirements:

a. a shatter resistant inspection window shall be installed in an interior wall unless secondary containment is provided for chlorine gas;

b. all openings between the rooms and the remainder of the plant shall be sealed;

c. doors shall be equipped with panic hardware, assuring ready means of exit and opening outward only to the building exterior;

d. a ventilating fan with a capacity to complete one air change per minute when the room is occupied; where this is not appropriate due to the size of the room, a lesser rate may be considered;

e. the ventilating fan shall take suction near the floor and as great a distance as is practical from the door and air inlet, with the point of discharge located so as not to contaminate air inlets to any rooms or structures;

f. air inlets with corrosion resistant louvers shall be installed near the ceiling;

g. air intake and exhaust louvers shall facilitate airtight closure;

h. separate switches for the ventilating fan and for the lights shall be located outside and at the inspection window. Outside switches must be protected from vandalism. A signal light indicating ventilating fan operation shall be provided at each entrance when the fan can be controlled from more than one point;

i. vents from chlorinator and storage areas must be screened and discharge to the outside atmosphere, above grade;

j. floor drains are discouraged. Where provided, the floor drains must discharge to the outside of the building and not be connected to other internal or external drainage systems; and

k. provisions should be made to chemically neutralize chlorine gas where feed and/or storage is located near residential or developed areas in the event of any measured chlorine release. The equipment must be sized to treat the entire contents of the largest storage container on site.

4. Chlorine gas not stored in a room shall be:

a. protected from direct sunlight and windblown debris;

b. shielded from public view;

c. located inside a fenced and secure area;

d. secured in a fixed position, and

e. all chlorine pipelines shall be under vacuum with no pressure chlorine lines allowed.

5. Chlorine gas feed systems shall be of the vacuum type and include the following.

a. vacuum regulators on all individual cylinders in service; and

b. service water to injectors/eductors shall be of adequate supply and pressure to operate feed equipment within the needed chlorine dosage range for the proposed system.

6. Pressurized chlorine feed lines shall not carry chlorine gas beyond the chlorinator room.

7. Full and empty cylinders of chlorine gas shall meet the following requirements:

a. housed only in the chlorine storage room or designated area conforming with §209. A.4 of this Part;

b. isolated from operating areas;

c. restrained in position;

d. stored in locked and/or secure rooms separate from ammonia storage; and

e. protected from direct sunlight or exposure to excessive heat.

B. Acids and Caustics. Acids and caustics shall:

1. be kept in closed corrosion-resistant shipping containers or bulk liquid storage tanks; and

2. not be handled in open vessels, but should be pumped in undiluted form to and from bulk liquid storage tanks and covered day tanks or from shipping containers through suitable hoses, to the point of treatment.

C. Sodium chlorite for chlorine dioxide generation. Proposals for the storage and use of sodium chlorite shall be approved by the state health officer prior to the preparation of final plans and specifications. Provisions shall be made for proper storage and handling of sodium chlorite to eliminate any danger of fire or explosion associated with its powerful oxidizing nature.

1. Storage. The storage of sodium chlorite shall comply with the following.

a. Sodium chlorite shall be stored by itself in a separate room and preferably shall be stored in an outside building detached from the water treatment facility. It shall be stored away from organic materials because many materials will catch fire and burn violently when in contact with sodium chlorite.

b. The storage structures shall be constructed of noncombustible materials.

c. If the storage structure shall be located in an area where a fire may occur, water shall be available to keep the sodium chlorite area cool enough to prevent heat induced explosive decomposition of the sodium chlorite.

2. Handling. The criteria for handling of sodium chlorite is as follows.

a. Care should be taken to prevent spillage.

b. An emergency plan of operation should be available for the clean-up of any spillage.

c. Storage drums shall be thoroughly flushed to an acceptable drain prior to recycling or disposal.

3. Feeders. Feeders shall comply with the following requirements.

a. Positive displacement feeders shall be provided.

b. Tubing for conveying sodium chlorite or chlorine dioxide solutions shall be Type 1 PVC, polyethylene or materials recommended by the manufacturer.

c. Chemical feeders may be installed in chlorine rooms if sufficient space is provided or in separate rooms meeting the requirements of §209. A.3 of this Part.

d. Feed lines shall be installed in a manner to prevent formation of gas pockets and shall terminate at a point of positive pressure.

e. Check valves shall be provided to prevent the backflow of chlorine into the sodium chlorite line.

D. Sodium Hypochlorite. Sodium hypochlorite storage and handling procedures should be arranged to minimize the slow natural decomposition process of sodium hypochlorite either by contamination or by exposure to more extreme storage conditions. In addition, feed rates should be regularly adjusted to compensate for this progressive loss in chlorine content.

1. Storage. The storage of sodium hypochlorite shall comply with the following.

a. Sodium hypochlorite shall be stored in the original shipping containers or in sodium hypochlorite compatible bulk liquid storage tanks.

b. Storage containers or tanks shall be located out of the sunlight in a cool area and shall be vented to the outside of the building when enclosed.

c. Wherever reasonably feasible, stored sodium hypochlorite shall be pumped undiluted to the point of addition. Where dilution is utilized, deionized or softened water should be used.

d. Storage areas, tanks, and pipe work shall be designed to avoid the possibility of uncontrolled discharges.

e. Reusable sodium hypochlorite storage containers shall be reserved for use with sodium hypochlorite only and shall not be exposed to contamination.

2. Feeders. Sodium hypochlorite feeders shall comply with the following.

a. Positive displacement pumps with sodium hypochlorite compatible materials for wetted surfaces shall be used.

b. To avoid air locking in smaller installations, small diameter suction lines shall be used with foot valves and degassing pump heads as required.

c. In larger installations flooded suction shall be used with pipe work arranged to ease escape of gas bubbles.

d. Calibration tubes or mass flow monitors which allow for direct physical checking of actual feed rates shall be provided.

e. Injectors shall be made removable for regular cleaning where hard water is to be treated.

E. Ammonia. Ammonia for chloramine formation may be added to water either as a water solution of ammonium sulfate, or as aqua ammonia, or as anhydrous ammonia (purified 100 percent ammonia in liquid or gaseous form). Special provisions required for each form of ammonia are listed below.

1. Ammonium Sulfate. A water solution is made by addition of ammonium sulfate solid to water with agitation. The tank and dosing equipment contact surfaces should be made of corrosion resistant non-metallic materials. Provision should be made for removal of the agitator after dissolving the solid. The tank should be fitted with an air-tight lid and vented outdoors. The application point should be at the center of treated water flow at a location where there is high velocity movement.

2. Aqua Ammonia (ammonium hydroxide). When the exception criteria in §209. E.2.i of this Part is not met, Aqua ammonia feed pumps and storage shall be enclosed and separated from other operating areas. The aqua ammonia room shall conform to §209. A.3 of this Part and to the following:

a. corrosion resistant, closed, pressurized tank shall be used for bulk liquid storage and day tanks, vented through inert liquid traps to a high point outside;

b. an incompatible connector or lockout provisions shall be provided to prevent accidental addition of other chemicals to the bulk liquid storage tank(s);

c. the bulk liquid storage tank(s) should be designed to avoid conditions where temperature increases cause the ammonia vapor pressure over the aqua ammonia to exceed atmospheric pressure. Such provisions shall include either:

i. refrigeration or other means of external cooling, and/or;

ii. dilution and mixing of the contents with water without opening the bulk liquid storage tank.

d. An exhaust fan shall be installed to withdraw air from high points in the room and makeup air shall be allowed to enter at a low point.

e. The aqua ammonia feed pump, regulators, and lines shall be fitted with pressure relief vents discharging outside the building away from any air intake and with water purge lines leading back to the headspace of the bulk storage tank.

f. The application point should be placed in a region of rapid, preferably turbulent, water flow.

g. Provisions should be made for easy access for removal of calcium scale deposits from the injector.

h. Provision of a modestly-sized scrubber capable of handling occasional minor emissions should be considered.

i. An exception to the requirement for enclosing aqua ammonia shall be made when aqua ammonia is stored in a manner which satisfies all of the following criteria:

i. protection is provided from direct sunlight and windblown debris;

ii. shielded from public view;

iii. located inside a fenced and secured area, and

iv. secured in a fixed position.

3. Anhydrous Ammonia. Anhydrous ammonia is readily available as a pure liquefied gas under moderate pressure in cylinders or as a cryogenic liquid boiling at ^-15° Celsius at atmospheric pressure. The liquid causes severe burns on skin contact.

a. When the exception criteria in §209. E.3.i of this Part is not met, anhydrous ammonia storage and feed systems (including heaters where required) shall be enclosed and separated from other works areas and constructed of corrosion resistant materials. Bulk anhydrous ammonia storage tanks holding more than 500 gallons shall not be located in an enclosed area.

b. An emergency air exhaust system, as in §209. A.3 of this Part but with an elevated intake, shall be provided in the ammonia storage room.

c. Leak detection systems shall be provided in all areas through which ammonia is piped.

d. Special vacuum breaker/regulator provisions must be made to avoid potentially violent results of backflow of water into cylinders or storage tanks.

e. Carrier water systems of soft or pre-softened water may be used to transport ammonia to the application point and to assist in mixing.

f. The ammonia injector should use a vacuum eductor or should consist of a perforated tube fitted with a closely fitting flexible rubber tubing seal punctured with a number of small slits to delay fouling by lime or other scale deposits.

g. Provision should be made for the periodic removal of lime or other scale deposits from injectors and carrier piping.

h. Consideration should be given to the provision of an emergency gas scrubber capable of absorbing the entire contents of the largest anhydrous ammonia storage unit whenever there is a risk to the public as a result of potential ammonia leaks.

i. An exception to the requirement for enclosing anhydrous ammonia shall be made when anhydrous ammonia is stored in a manner which satisfies all of the following criteria:

i. protection is provided from direct sunlight and windblown debris;

ii. shielded from public view;

iii. located inside a fenced and secured area, and

iv. secured in a fixed position.

F. Potassium Permanganate. Design criteria for potassium permanganate is as follows.

1. A source of heated water should be available for dissolving potassium permanganate, and

2. mechanical mixers shall be provided.

G. Fluoride. Sodium fluoride, sodium silicofluoride and fluorosilicic acid shall conform to the applicable AWWA Standards and be certified to NSF/ANSI Standard 60. Other fluoride compounds which may be available shall be approved by the state health officer.

1. Storage. Design criteria for storage of fluoride compounds is as follows.

a. Fluoride chemicals should be isolated from other chemicals to prevent contamination.

b. Compounds shall be stored in covered or unopened shipping containers and should be stored inside a building.

c. Unsealed storage units for fluorosilicic acid should be vented to the atmosphere at a point outside any building. The vents to atmosphere shall be provided with a corrosion resistant 24 mesh screen.

d. Bags, fiber drums and steel drums should be stored on pallets.

2. Chemical Feed Equipment and Methods. Design criteria for chemical feed and methods for fluoride compounds is as follows.

a. At least two diaphragm operated anti-siphon devices shall be provided on all fluoride saturator or fluorosilicic acid feed systems.

i. one diaphragm operated anti-siphon device shall be located on the discharge side of the feed pump; and

ii. a second diaphragm operated anti-siphon device shall be located at the point of application unless a suitable air gap is provided.

b. A physical break box may be required in high hazard situations where the application point is substantially lower than the metering pump. In this situation, either a dual head feed pump or two separate pumps are required and the anti-siphon device at the discharge side of the pump may be omitted.

c. Scales, loss-of-weight recorders or liquid level indicators, as appropriate, accurate to within five percent of the average daily change in reading shall be provided for chemical feeds.

d. Feeders shall be accurate to within five percent of any desired feed rate.

e. Fluoride compound shall not be added before lime-soda softening or ion exchange softening.

f. The point of application if into a horizontal pipe, shall be in the lower half of the pipe, preferably at a 45 degree angle from the bottom of the pipe and protrude into the pipe one third of the pipe diameter.

g. Except for constant flow systems, a device to measure the flow of water to be treated is required.

h. Water used for sodium fluoride dissolution shall be softened if hardness exceeds 75 mg/L as calcium carbonate.

i. Fluoride solutions shall be injected at a point of continuous positive pressure unless a suitable air gap is provided.

j. The electrical outlet used for the fluoride feed pump should have a nonstandard receptacle and shall be interconnected with the well or service pump, or have flow pacing as allowed by the state health officer,

k. Saturators should be of the up flow type and be provided with a meter and backflow protection on the makeup water line.

l. Consideration shall be given to providing a separate room for fluorosilicic acid storage and feed.

3. Secondary control systems for fluoride chemical feed devices shall be provided as a means of reducing the possibility for overfeed; these may include flow or pressure switches, break boxes, or other devices.

4. Personal protective equipment as outlined in §207. D of this Part shall be provided for operators handling fluoride compounds. Deluge showers and eye wash devices shall be provided at all fluorosilicic acid installations.

5. Dust control requirements are as follows.

a. Provision shall be made for the transfer of dry fluoride compounds from shipping containers to storage bins or hoppers in such a way as to minimize the quantity of fluoride dust which may enter the room in which the equipment is installed. The enclosure shall be provided with an exhaust fan and dust filter which places the hopper under a negative pressure. Air exhausted from fluoride handling equipment shall discharge through a dust filter to the outside atmosphere of the building.

b. Provision shall be made for disposing of empty bags, drums or barrels in a manner which will minimize exposure to fluoride dusts. A floor drain should be provided to facilitate the washing of floors.

6. Equipment shall be provided for measuring the quantity of fluoride in the water. Such equipment shall be subject to the approval of the state health officer.

H. Activated carbon is a potentially combustible material requiring isolated storage.

1. Storage facilities should be:

a. fire proof; and

b. equipped with explosion-proof electrical outlets, lights and motors in areas of dry handling.

2. Bags of powdered carbon should be stacked in rows with aisles between in such a manner that each bag is accessible for removal in case of fire.

La. Admin. Code tit. 51, § XII-209

Promulgated by the Department of Health, Office of Public Health, LR 44330 (2/1/2018), effective 8/1/2018.

AUTHORITY NOTE: Promulgated in accordance with the provisions of R.S. 40:4.A.(8), 40:4.13.D.(1)(2) and 40:5.A.(2)(3)(5)(6)(7)(17).