Environmental Health & Safety

Cross Connection / Backflow Prevention Plan


January 2012

 

Scope:

The Cross Connection / Backflow Prevention Plan has been designed, implemented and maintained in accordance with the requirements of the Massachusetts Department of Environmental Protection 310 CMR 22.22. This plan, which is part of the Amherst College Environmental Compliance initiative shall meet or exceed the expectations of the Environmental Health and Safety Committee and the Standard Operating Guidelines of Amherst College.

Purpose:

Amherst College has put together this policy in an effort to prevent the contamination of drinking water both on campus and off. The goal is to eliminate the possibility of cross connections with the installation of backflow prevention devices when re-plumbing or re-piping is not a possibility. These backflow preventers are approved, installed and maintained in accordance with the Commonwealth of Massachusetts, Department of Environmental Protection and the Town of Amherst, Department of Public Works.

Applicability:

The approval, design, installation, maintenance and use of backflow prevention devices shall be the responsibility of the Physical Plant (Design & Construction, Environmental Health & Safety, the Plumbing/Mechanical Shop, if applicable), the Town of Amherst (Department of Public Works and the Board of Health, when applicable).

Definitions:

Air Gap Separation– a method of preventing backflow through the use of an unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe or faucet supplying water to a plumbing device or fixture, tank or other device and the flood level rim of the receptacle.

Atmospheric Vacuum Breaker – an approved backflow device used to prevent back siphonage that is not designed for use under static line pressure.

Back Pressure – pressure created which causes water or other liquids to flow or move in the opposite direction of that which is desired.

Back Siphonage – backflow which is due to reduced or sub-atmospheric pressure within a water system.

Backflow – the flow of water or other liquids into distribution pipes of a potable water supply from any source other than the intended source.

Backflow Preventer with Atmospheric Vent – a device which has (2) independently operating check valves separated by an intermediate chamber with a means for automatic venting into the atmosphere, in which the check valves are force loaded to a normally closed position and the venting means is force loaded to a normally open position.

Backflow Prevention Device (approved) – a method used to prevent backflow that has been approved by the Commonwealth of Massachusetts, Department of Environmental Protection.

Backflow Prevention Device Tester (certified) – the individual who holds a certificate for the testing of backflow preventers in the Commonwealth of Massachusetts.

Code of Massachusetts Regulations (C.M.R.) – regulatory requirements of the Commonwealth of Massachusetts

Contaminant – any biological, chemical, physical or radiological material or substance in water or other vehicle for which it was not intended.

Cross Connection – any actual or potential connection between a distribution pipe of potable water from a public water system and any waste pipe, soil pipe, drain or other unapproved source. Cross connection also includes any by-pass arrangements, jumper connections, removal section, swivel or changeover connection and other permanent or temporary connection through which backflow can or may occur.

Department – the Department of Environmental Protection for the Commonwealth of Massachusetts

Design Date Sheet – a report form, designated by the Department of Environmental Protection (D.E.P.), which is to be submitted to the D.E.P. or its designee (Town of Amherst, Department of Public Works) along with plans for each installation of a reduced pressure backflow preventer or double check valve assembly, or for each change to any such device already installed, describing and showing the details of the specific installation.

Double Check Valve Assembly – a backflow prevention device that incorporates an assembly of check valves, with strut-off valves at each end and appurtenances for testing.

Inspection – a survey by a qualified individual to determine the existence and location of cross connections and / or the physical examination and testing of an installed backflow prevention device to verify that the backflow prevention device is functioning properly.

Massachusetts General Law (M.G.L.) – Laws promulgated by the Commonwealth of Massachusetts.

Potable Water – water from any source which has been approved by the Department of Environmental Protection (D.E.P.) for human consumption.

Pressure Vacuum Breaker – an approved backflow prevention device designed to prevent only back siphonage and which is designed for use under static line pressure.

Reduced Pressure Vacuum Preventer – an approved backflow prevention device that incorporates:

  • two (2) or more check valves
  • an automatically operating differential relief valve located between (2) checks
  • two (2) strut-off valves
  • necessary appurtenances for testing; and which is designed to operate so that:
  1. The pressure in the zone between the two (2) check valves is maintained at a value less than the pressure on the public water system side of the device, and
  2. At cessation o normal flow, the pressure in the zone between the two (2) check valves is maintained at a value less than the pressure on the public water system side of the device, and
  3. In the case of leakage of either check valve, the differential relief valve shall operate to maintain reduced pressure in the zone discharging to the atmosphere.
Supplier of Water– The Town of Amherst, Department of Public Works

Unapproved Source – the source or distribution system for any water or other liquid which has not been approved by the Department of Environmental Protection as being safe or sanitary for human consumption, including but not limited to any waste pipe, soil pipe, sewer, drain, or non-acceptable potable water system material.

Cross Connections and the Public Water System

The Department of Public Works for the Town of Amherst in cooperation with the Amherst College Physical Plant Mechanical Department Supervisor or his / her designee shall inspect the water distribution systems on campus to determine hazards, identify solutions and implement corrective action to eliminate the potential for cross contamination. The representatives for the Town and the College shall conduct inspections at least twice annually to test the effectiveness of the existing backflow preventers and to determine where and what type of protection devices are needed elsewhere on campus.
  • The inspections will be performed during the months of April and October at the request of the Town of Amherst, Department of Public Works.

Degree of Hazard(s)

The Town of Amherst, Department of Public Works (a.k.a. Supplier of Public Water) will determine the "Degree of Hazard". This determination will help to establish the most appropriate type of backflow prevention device for the source of water. The conditions that identify the "Degree of Hazard" are classified as either a contamination hazard or pollution hazard. The types of hazard can be further defined as:
  1. Health Hazard which means that there is an actual or potential threat of contamination of a biological, chemicals, physical or radiological nature to the public potable water system or other consumable water system that will or could cause a danger to public health.
  2. Plumbing Hazardis an internal or plumbing type cross connection in a potable water system that may be either a contamination hazard or pollution hazard. This type of hazard could include, but is not limited to; cross connections of drench showers, eyewash stations, lavatories, lawn sprinkler systems, sinks, slop sinks, toilets, washing machines and water fountains. These types of hazards can be found in commercial, industrial and residential occupancies. In order to protect the potable water supply, the plumbing hazard would have to be protected by some type of appropriate cross connection control assembly.
  3. Pollution Hazard is an actual or potential treat to the physical properties of the water system or the potability of the public water supply system but which would not constitute a health or system hazard.
  4. System Hazard – is an actual or potential threat of severe danger to the physical properties of the public or private potable water system or of a pollution or contamination which would have a prolonged effect on the quality of the potable water in the system.

Potential Cross Connection Hazards

The Amherst College Physical Plant departments of Design & Construction, Environmental Health and Safety, and the Plumbing/Mechanical Shop shall be aware of and routinely inspect for potential threats to the water system that could adversely affect the health and safety of the community, both on and off campus. Areas of concern for Amherst College could include:
  • Chemical / Cleaning Mixing Stations
  • Cooling Towers
  • Custodial Sinks
  • Dishwashers
  • Emergency Drench Showers
  • Eyewash Stations
  • Firefighting Systems - including sprinklers and standpipes
  • Garbage Disposals
  • Heat Exchangers
  • Hose bibs (certain types)
  • Industrial Fluid Systems - those that contain cutting and hydraulic fluids, coolants and other similar types of contaminants.
  • Irrigation Systems
  • Laboratories
  • Laundries
  • Photography Studios
  • Pressure Cookers
  • Priming Lines – including air conditioning pumps, booster pumps, sewer pumps
  • Refrigeration Units
  • Steam Generating Facilities
  • Swimming Pools

Hazard Identification

When the Town of Amherst or College has identified a hazard or potential hazard to the public water system, the College, under the rules and regulations of the Town of Amherst and the Massachusetts Department of Environmental Protection (D.E.P.) shall install an approved backflow prevention device(s).
  1. The type of approved backflow prevention device and the designated location for that appliance shall depend upon the nature of the hazard and the recommendation of the Department of Public Works.
  2. All cross connection protection devices shall be approved and permitted in accordance with 310 CMR 22.22.
  3. The Town of Amherst or Massachusetts Department of Environmental Protection shall establish a time for completion of the necessary corrections or removal of actual or potential cross connections, taking into consideration the degree of hazard involved and the time required to obtain and install the needed equipment.
  • If proper protection has not been provided after a reasonable period of time (in accordance with local and state requirements), the Town can physically remove the public water supply from the College piping system in such a manner that the two (2) systems cannot again be connected by an unauthorized person(s).

Town of Amherst Responsibilities

The Town of Amherst is responsible for:
  1. The quality of water delivered to the College to the last free flowing outlet and for the health and safety of the public water system under its jurisdiction.
  2. An annual water quality is submitted to Amherst College by the Town and is made available on out web page at Environmental Health & Safety.
  3. Having a cross connection control distribution protection program plan, approved by the Department of Environmental Protection as specified in 310 CMR 22.22(3)(b)
  4. Maintaining a schedule of all facilities inspected and surveyed
  5. Maintaining records of all device locations
  6. Correspondence with the College, including "notices of violation".
  7. Keeping a list of devices and inspections of approved backflow prevention devices.
  8. Ensuring that all inspections and surveys for cross connections are conducted by a person who is certified by the D.E.P. as a Cross Connection Control Surveyor
  9. Not allowing any cross connection at any point in the system, unless the cross connection is approved in accordance with 310 CMR 22.22.
  10. Ensuring that all cross connection protection devices are inspected and tested in accordance with the public water supply system program plan, as approved by the D.E.P., 310 CMR 22.22(14).
  11. Establishing an audit program for devices not tested by the Town.
  12. Taking appropriate action to eliminate cross connections and hazardous conditions, strongly promote compliance, and take the appropriate enforcement action, if necessary.
  13. Notifying the College representative(s) of any violations.
  14. Reviewing and approving design data sheets and plans for proposed new installations of reduced pressure backflow preventers, double check valve assemblies, and air gap separations with tank and pump arrangements, effective January 01, 1999.
  15. Ensuring that, upon completion of the installation of the backflow device that they are installed according to the design data sheet and plans and tested for proper operation, effective January 01, 1999.

College Responsibilities

Amherst College is responsible for:
  1. Apply for, obtain and comply with all necessary approvals and permits from the Town of Amherst and/or the Massachusetts Department of Environmental Protection (D.E.P.) for the maintenance of cross connections, as specified in 310 CMR 22.22, including the permit issued by the D.E.P. for each cross connection protection device.
  2. Having suitable arrangements made so that inspections can be made during normal business hours
  3. Maintaining a spare parts kit and any special tools required for the removal and re-assembly of devices
  4. Providing the necessary labor for inspection and testing by the Certified Backflow Prevention Device Tester.
  5. Overhaul, repair or replacement of the backflow prevention device within 14 days of the initial inspection date and retest pursuant to 310 CMR 22.22 (14)(f).
  6. Submitting copies of the Inspection and Maintenance Report Form as required by the Town of Amherst.
  7. Maintaining a complete set of records for all devices for the life of said devices including as-built plans and design data sheets; maintaining for seven (7) years the Inspection and Maintenance Report Forms for tests conducted by the Certified Backflow Prevention Device Tester
  8. Making certain that the cross connection device is tested in accordance with 310 CMR 22.22(14), or as required by the Town.
  9. Preventing the placement of hoses in the sink below the top of the sink, to prevent the possibility of non-potable water from entering the potable water supply.

Certified Backflow Preventer Tester’s Responsibilities

The Certified Backflow Preventor Tester is responsible for:
  1. Having a backflow preventer test kit that is maintained in proper working order and calibrated annually.
  2. Recording the results for each inspection conducted on forms approved by the D.E.P.
  3. Submitting copies of the inspection reports to the Town and the College within 30 days of the inspection; and
  4. Maintaining records of all tests for a minimum of seven (7) years

Local Plumbing Inspector’s Responsibilities

The Local Plumbing Inspector is responsible for:
  1. Ensuring that potable water supply systems are designed, installed and maintained in a manner that prevents contamination from non-potable liquids, solids or gases which may be introduced to a potable water supply.
  2. Reviewing plans and specifications for plumbing work under 248 CMR 2.04(5) and before issuing a permit, the plumbing inspector, as required by 248 CMR 2.14, shall require the installation of appropriate devices in accordance with 310 CMR 22.00.

Approval Required

Amherst College shall not install or remove or contract with another company or person for the installation or removal of any reduced pressure backflow preventer or double check valve assembly required by 310 CMR 22.22, unless a design data sheet with plans showing the method of protection of the public water distribution system has been approved by the D.E.P., its designee or the Town of Amherst for the installation of such device. Thus, in order to pursue an installation:
  1. The College shall obtain approval from the local plumbing inspector or the head of the local fire department, to the extent required by the State Plumbing Code, 248 CMR 2.04(3) or M.G.L. Chapter 148, section 27A, for the initial installation or retrofit for any change in the installation of any air gap separation with tank and pump arrangement, reduced pressure backflow preventer, or double check valve assembly.
  2. All design data sheets and plans for the installation of backflow prevention devices shall be reviewed by a certified cross connection surveyor as of December 31, 1998.
  3. Before the installation of any pressure or atmospheric vacuum breaker, backflow preventer with intermediate atmospheric vent, or barometric loop, the plans and specifications for the plumbing work must receive a permit issued by the plumbing inspector in accordance with 248 CMR 2.04(3).
  • For these devices, a plumbing permit issued under 248 CMR 2.04(3) shall constitute installation approval pursuant to 310 CMR 22.22.

Permit Requirement

Amherst College shall apply for and obtain a permit from the D.E.P. for each reduced pressure backflow preventer and double check valve assembly installed on the premises and shall pay an annual permit fee to the D.E.P. pursuant to 310 CMR 4.00. The D.E.P. reserves the right to revoke or suspend any conditional approval and / or permit for cause.

Device Location

The location of each approved backflow prevention device, with respect to the plumbing on campus and the service connections to the premises, shall be based upon the degree of existing or potential health hazard, and shall conform to the following specific requirements:
  1. Approved backflow prevention devices shall be located so that protection of all cross connections is achieved with a minimum number of devices.
  2. Approved backflow prevention devices shall be located so as to provide in-plant protection.
The following types of facilities at Amherst College have the potential to present high health hazard conditions and in-plant protection shall be supplemented by installation of a reduced pressure backflow preventer or an air gap separation at the meter or property line unless otherwise specified by the D.E.P. or the Town of Amherst.
  • Laboratories, except when the D.E.P. or the Town has made specific determination that no health hazard exists on the premises.
If the College, the Town or the D.E.P. determine that it is unreasonable to locate all cross connections within the premises or the Town or D.E.P. determines that protection of all cross connections is unreasonable for economic reasons, then:
  1. The public water supply distribution system shall be protected by installation of a reduced pressure backflow preventer or an air gap separation at the meter or property line, and
  2. The College shall provide a safe, alternative supply of potable water, well marked and labeled to all domestic water fixtures on the premises.

Types of Backflow Prevention Devices Required

The type of backflow prevention devices required shall be determined by the provisions of 310 CMR 22.22(10), Table 310 CMR 22-1. See the guide for the type of protection required reference above.

Approval of Devices for Use in the Commonwealth of Massachusetts

Types and models of atmospheric and pressure vacuum breakers and types and models of backflow preventers with intermediate atmospheric vent which may be used in Massachusetts for certain low hazard applications referred to in the State Plumbing Code shall be those meeting the requirements of, and approved by, the Board of State Examiners of Plumbers and Gas Fitters. Except as further restricted by the D.E.P. as provided in 310 CMR 22.22 (10), all other backflow prevention devices meeting the requirements of, and approved by, the Board of State Examiners of Plumbers and Gas Fitters may be used in Massachusetts. Only types and models of reduced pressure backflow preventers, double check valve assemblies, and manufactured air gap separation devices which have been specifically evaluated and approved by the D.E.P., and included on the list of approved backflow prevention devices maintained by the D.E.P., may be used as cross connection control in Massachusetts.

Installation Requirements

Reduced Pressure Backflow Preventers may be used to protect against backflow caused by back pressure or back siphonage and to protect a public water supply system from substances which are hazardous to health only when they are installed in the following manner:
  1. For devices installed as in-plant protection, the reduced backflow preventer shall be installed on the College’s side of the water meter on the potable water supply line.
  2. Before installing a reduced pressure backflow preventer, all pipes shall be thoroughly flushed to remove all foreign material.
  3. Drinking and domestic water lines, lines for safety showers, and lines for eyewash stations must be taken off the upstream side of reduced pressure backflow preventers for devices installed as in-plant protection.
  4. The reduced pressure backflow preventer shall be located so as to permit easy access and provide adequate and convenient space for maintenance, inspection and testing.
  5. The College must be able to shut down water lines after reasonable notice during normal business hours to permit necessary testing and maintenance of the device provided that if it is not possible to meet the requirement a by-pass line equipped with an approved type reduced pressure backflow preventer shall be installed.
  6. The reduced pressure backflow preventer and strut-off valves must be installed in a horizontal alignment between three (3) and four (4) feet from the floor to the bottom of the device and a minimum of twelve (12) inches from any wall, unless the device is approved by the D.E.P. for vertical installations.
  7. Tightly closing valves must be installed at each end of the device and be immediately accessible unless otherwise approved by the D.E.P. or the Town of Amherst.
  8. The device must be protected against freezing, flooding and mechanical damage.
  9. If the device is to be installed on the hot water line, a device approved for use at the elevated temperature must be used.
  10. If a drain is to be provided for the relief valve port, there must be an approved air gap separation between the port and the drain line. To be approved, the air gap must be at least twice the internal diameter of the discharge line.
  11. Pit installation shall be approved only as provided in 310 CMR 22.22(12)(f).
  12. All water lines shall be color coded according to the state plumbing code, except that water filtration plants, pumping stations, sewage treatment plants and sewage pumping stations shall label all water lines in lieu of color coding.
  13. Non-potable water in the laboratories and at other locations that were not designed for human consumption must be labeled to prevent human consumption.

Double Check Valve Assemblies

Double check valve assemblies may be used to protect against backflow caused by back pressure or back siphonage and to protect a public water supply system from substances which are objectionable, but not hazardous to health, only if they are installed in the following manner:
  1. Drinking and domestic water lines, lines for safety showers, and lines for eye wash stations must be taken off the upstream side of the double check valve assembly for devices installed as in-plant protection.
  2. The double check valve assembly shall be installed with adequate space to facilitate maintenance, inspection and testing.
  3. The double check valve must be installed horizontally and the top of the double check valve assembly must be between 30 and 53 inches from the floor to the bottom of the device and a minimum of 12 inches from any wall, unless otherwise approved by the D.E.P. or the Town of Amherst.
  4. If a water meter is not provided on the upstream side of an approved swing type double check valve assembly, a three (3) to five (5) foot spacer must be installed between the check valves.
  5. Tightly closing valves must be installed at each end of the device and be immediately accessible unless otherwise approved by the D.E.P. or the Town.
  6. Double check valve assemblies must be provided with suitable connections and appurtenances for testing.
  7. The device must be protected against freezing, flooding and mechanical damage.
  8. Pit installation will be approved only as provided in 310 CMR 22.22(12)(f)

Vacuum Breakers

Vacuum breakers shall not be used to protect against backflow due to back pressure and shall not be installed as protection for high hazard conditions as determined by the D.E.P. or the Town of Amherst. Vacuum breakers may be used for low health hazards only if they are installed in the following manner:
  1. Vacuum breakers must be installed at least six (6) inches above the flood level rim of the fixture they serve
  2. Atmospheric vacuum breakers must be installed downstream of the last shut off servicing the fixture or equipment.
  3. Vacuum breakers must not be installed in locations where the device is subject to corrosive fumes, dust or grit.
  4. Vacuum breakers must be protected against freezing, flooding and mechanical damage.
  5. Atmospheric vacuum breakers shall not be used under conditions of static line pressure.
  • Pressure vacuum breakers may be used under conditions of static line pressure.

Air Gap Separation

Air gap separation may be used to protect against backflow caused by back siphonage and to protect public water supply system from substances which are hazardous to health and shall be approved for use only when installed in the following manner:
  • The minimum air gap must be twice the diameter of the effective opening of the inlet pipe above the flood level rim of the receptacle being fed, but in no case shall it be less than one (1) inch.

Pit Installation

No devices shall be installed in pits except as specifically approved by the D.E.P. or the Town of Amherst in cases of unique circumstances, and must comply with all OSHA standards where applicable for work in confined spaces then only as follows:
  1. The pit interior shall be a minimum of ten (10) feet long, six (6) feet wide and must have a clear height of six and one-half (6) feet.
  2. The pit must be watertight
  3. The pit opening and man hole cover must be at least 30" in diameter
  4. The foothold inserts must be of steel, aluminum, or other material approved by the D.E.P., must be a maximum of twelve (12) inches apart, and must be installed so that the top foothold is within twelve inches of the manhole cover and the bottom foothold is within twelve (12) inches of the pit floor.
  5. An adequate drain must be installed and shall meet the regulatory requirements imposed by the Town of Amherst.
  6. The pit floor shall be pitched to the drain, unless there is a possibility of chemical or oil entering that drain. If so, the drain shall be blocked with hydraulic cement or similar material.
  7. If built in a roadway, the top of the pit must be adequately reinforced.