Category: LT2 Cryptosporidium

Appendix G

Envirochek™ Field Filtration for Cryptosporidium

Procedure for Field-Filtering Samples for Cryptosporidium Analysis Using the Pall Life Sciences Envirochek™ or Envirochek™ HV Capsules

1.0      Materials

The following materials should be available before collecting sample:

• Several pairs of new, powder-free latex gloves
• Sample collection form (Appendix F)
• Pall Life Sciences Envirochek™ or Envirochek™ HV capsule (recommend that two capsules be kept on hand in case the first one clogs prior to filtering 10 L)
• Sanitary $30 L carboy (if sample is not from a pressurized source)
•  Stopwatch
•  Sample label
• Cooler, approximately 16-quart
• Temperature monitoring device (e.g., thermometer vial, Thermochron™ iButton, or equivalent) (if measuring temperature during shipment)
• Two large plastic trash bags
• One 8-lb bag of ice or gel ice packs
• Three gallon size ziplock bags
• Strapping tape
• Two self-adhesive plastic airbill sleeves
• Airbill for shipment
• The following items may be purchased as a unit for sampling from a vendor or laboratory supplying sampling apparatus for field filtering Cryptosporidium samples:
• Pump (if sample is not from a pressurized source) – Electric centrifugal or Electric peristaltic pump, or any equivalent pump that can create a flow of approximately 2 L/min
• Two 0.5-in. X 0.375-in. barbed reducing connectors
• Five lengths of clean 12.7-mm (0.5-in.) internal-diameter clear, vinyl, laboratory tubing
• Five pairs of hose clamps fit to tubing
• One 0.5-in. x 3-in. nipple
• One coupling to fit 0.5-in. internal diameter tubing
• One roll teflon tape
• One 0.5-in. x 0.5-in. x 0.25-in. tee Q  Six 0.5-in. barbed male adapters            One garden hose barbed adapter  Pressure regulator

If the sample will be collected from a pressurized source, use the sample collection procedures in Section

2.1. If the sample will be collected from an unpressurized source, use the sample collection procedures in Section 2.2.

2.1                          Sample Filtration from a Pressurized Source

• Before connecting the sampling system to the tap or source, turn on the tap and allow the water to flow for 2 to 3 minutes until the temperature has stabilized or until any debris that has accumulated in the source water lines has cleared and the turbidity in the water becomes visibly uniform. Turn off the

• Put on a pair of powder-free latex gloves to prevent contamination from outside sources. Any contamination inside the sampling apparatus may bias the final

• Determine the pressure of the water source with the pressure

• Assemble the sampling system, minus the Envirochek™ /Envirochek™ HV capsule. In place of the Envirochek™ /Envirochek™ HV capsule, insert a 0.5-in. barbed connector between the outlet tubing from the sample valve or the pressure regulator or gauge and the inlet tubing of the flow totalizer, flow meter or control valve. For high pressure (>30 PSIG for Envirochek™ capsule or

>60 PSIG for Envirochek™ HV capsule) sites, the sampling system should be assembled in the following order, as shown in Figure 1 below:

• Reinforced influent tubing
• Pressure regulator
• Pressure gauge
• Reinforced inlet tubing
• Envirochek™ /Envirochek™ HV capsule
• Reinforced outlet tubing
• Flow totalizer (mechanical or graduated collection device)
• Flow rate meter with valve or flow control valve
• Effluent tubing to drain

Figure 1.Sample System Setup for Collecting Cryptosporidium Samples from a Pressurized Source ( >30 PSIG for Envirochek™ capsule or >60 PSIG for Envirochek™ HV capsule)

For low pressure (1 to 30 PSIG for Envirochek™ capsule or 1 to 60 PSIG for Envirochek™ HV capsule) sites, the sampling system should be assembled at the sample port valve in the following order, as shown in Figure 2 below :

• Influent tubing
• Envirochek™ /Envirochek™ HV capsule
• Outlet tubing
• Flow rate meter with valve or flow control valve
• Flow totalizer (mechanical or graduated collection device)
• Effluent tubing to drain

Figure 2.Sample System Setup for Collecting Cryptosporidium Samples from a Pressurized Source (1 – 30 PSIG for Envirochek™ capsule or 1 – 60 PSIG for Envirochek™ HV capsule)

• Connect the sampling system, with the connector in place of the Envirochek™ /Envirochek™ HV capsule, to the pressurized water system, using appropriate fittings and
• Slowly turn the tap to fully open. Allow a minimum of 20 L to flush the system. During this period, perform the following steps:
• Measuring the flow rate with the flow rate meter or the flow totalizer and a stopwatch, adjust the flow rate to approximately 2 L/min (approximately 0.5 gpm) for the Envirochek™ capsule or 4 L/min (approximately 1.0 gpm) for the Envirochek™ HV capsule. If a flow control valve at the appropriate flow rate is used, no adjustment of the flow rate is necessary. Using the pressure regulator, adjust the pressure to a maximum of 30 PSIG if using the Envirochek™ or 60 PSIG if using the Envirochek™ HV. Observe the system for leaks and take the necessary corrective action if any are
• Record the following information on the sample collection form (Appendix F):
  • Public water system (PWS) name
  • PWS address
  • Sampler name
  • Sample ID (optional)
  • Public Water System Identification (PWS ID) number
  • Public Water System facility ID number
  • Facility name
  • Sample collection point ID O Sample collection point name            Sample collection date
  • Source water type (optional [but required for E. coli sample forms])
  • Requested analysis (circle Cryptosporidium field sample for routine monitoring sample; circle both “Cryptosporidium field sample” and “Cryptosporidium matrix spike” sample if you are sending an additional sample with the monitoring sample for matrix spike analysis)
• After the assembly has been flushed, measure the turbidity of the source water and any optional water quality parameters such as temperature, and/or

• Turn off the water at the sample port valve when the flow rate has been adjusted and the system has been

• Record the following information on the capsule label with a waterproof pen:

PWS ID

Facility name

Date of sample collection

• Record the following information on the sample collection form:

Initial meter reading

• Remove the connector and in its place, install the Envirochek™ /Envirochek™ HV capsule in line, securing the inlet and outlet ends with the appropriate fittings/clamps.

Note!   Retain the vinyl caps provided with the Envirochek™ /Envirochek™ HV capsule. These caps will be needed to seal the capsule for shipment.

• Slowly turn on the pressurized water source. Adjust the flow rate to approximately 2 L/min for Envirochek™ capsule or 4 L/min for Envirochek™ HV capsule, if necessary. Record the following information on the capsule label or sample collection form:

Start time

• Vent the residual air in the capsule using the bleed valve by turning it counter-clockwise. When the capsule is full of water, close the bleed

• Monitor the water meter. When the targeted volume (actual sample volumes will be selected by the utility, but volumes are typically 10 L [2.64 gal] to 50 L [13.2 gal] and preferred to be consistent between sampling events for each source) has passed through the Envirochek™

/Envirochek™ HV capsule, shut off the water source. Allow the pressure to decrease until the water stops.

• Record the following information on the capsule label and/or sample collection form:

Stop time (when the water was shut off)

Final meter reading

Comments to laboratory, if needed

• With the capsule inlet pointed up, loosen the outlet end of the Envirochek™ /Envirochek™ HV capsule and allow water to drain as much as possible. Water drainage from the capsule through the outlet is acceptable, as the sample has passed through the membrane. Opening the bleed valve during the draining will speed the process. Be sure to close the valve when

• Disconnect the inlet end of the Envirochek™ /Envirochek™ HV capsule, making sure not to spill any of the water remaining in the capsule through the inlet port. This water is part of your sample. Capsule may be shipped with or without residual

• Seal the inlet of the capsule with the vinyl end cap that was previously

• Seal the outlet of the capsule with the vinyl end cap that was previously saved. Place the Envirochek™ /Envirochek™ HV capsule in a plastic ziplock bag for

• Immediately following sample collection, place the bag containing the capsule in a refrigerator to chill prior to packing the shipping cooler for shipment. If no refrigerator is available, and the sample will not be shipped for several hours, place the bag in the shipping cooler with ice to chill. Replace the ice with fresh ice before

Note!   Method 1622/1623 requires that the temperature of the sample upon arrival at the laboratory must be #20°C (but not frozen), and the laboratory must begin sample processing within 96 hours of sample collection. If the sample temperature and holding time requirements are not met, then the sample is invalid and must be recollected.

2.2                          Sample Filtration Using an Unpressurized Source

• Put on a pair of powder-free latex gloves to prevent contamination from outside sources. Any contamination inside the sampling apparatus may bias the final

• If sampling from a source of unlimited volume, it may be desirable to pre-flush the sampling system. Assemble the sampling system, minus the Envirochek™ /Envirochek™ HV capsule. In place of the Envirochek™ /Envirochek™ HV capsule, insert a 0.5-in. coupling to connect the influent tubing to the inlet tubing of the pump. The sampling system should be assembled in the following order, as shown in Figure 3 below:

Influent tubing

Envirochek™ /Envirochek™ HV capsule

Outlet tubing

Centrifugal or peristaltic pump

Tubing

Flow rate meter with valve or flow control valve

Flow totalizer (mechanical or graduated collection device)

Effluent tubing to drain

Figure 3.          Sample System Setup for Collecting Cryptosporidium Samples from an Unpressurized Source

When assembling sample chain, make sure that it is as airtight as possible in order to create a vacuum. To accomplish this, make sure that clamps are used at each connection and that rubber washers are inserted into the hose connections on the inlet and outlet ends of the centrifugal pump.

• Place the inlet end of the inlet tubing into the sample source, away from any walls, bottom, or other environmental

• Turn on the pump and allow a minimum of 20 L to flush the system. If sampling source water from a carboy, continuously refill the carboy as necessary to flush the system. As a recommendation, the carboy should not be removed from the sampling chain and should be refilled using a separate container. Observe the system for leaks and take the necessary corrective action if any are present. During this period, perform the following steps:

• Measuring flow rate with the flow rate meter or the flow totalizer and a stopwatch, adjust the flow rate to approximately 2 L/min (approximately 0.5 gpm) for the Envirochek™ capsule or 4 L/min (approximately 1.0 gpm) for the Envirochek™ HV capsule by varying the pump speed or adjusting the valve (if pump is not variable speed). If a flow control valve at the appropriate flow rate is used, no adjustment of the flow rate is

• Record the following information on the sample collection form:
  •          Public water system (PWS) name
  •          PWS address
  •          Sampler name
  •          Sample ID (optional)
  •          Public Water System Identification (PWS ID) number
  •          Public Water System facility ID number
  •          Facility name
  •          Sample collection point ID O Sample collection point name O           Sample collection date
  •          Source water type (optional [but required for E. coli sample forms])
  •          Requested analysis (circle Cryptosporidium field sample for routine monitoring sample; circle both “Cryptosporidium field sample” and “Cryptosporidium matrix spike” sample if you are sending an additional sample with the monitoring sample for matrix spike analysis)

• Turn off the pump when the flow rate has been adjusted and the assembly has been

• Record the following information on the capsule label:

PWS ID

Facility name

Date of sample collection

• Record the following information on the sample collection form:

Initial meter reading

• Install the Envirochek™ /Envirochek™ HV capsule in line, securing the inlet and outlet ends with the appropriate fittings/clamps.

Note!   Retain the vinyl caps provided with the Envirochek™ /Envirochek™ HV capsule. These caps will be needed to seal the capsule for shipment.

• Refill the carboy with the sample to be filtered. As a recommendation, the carboy should not be removed from the sampling assembly and should be refilled using a separate

• Turn on the pump. Adjust the flow rate to approximately 2 L/min for the Envirochek™ capsule or 4 L/min for the Envirochek™ HV capsule, if necessary. Record the following information on the capsule label and/or sample collection form:

Start time

• Monitor the water meter continuously refilling the carboy as needed. When the targeted volume (actual sample volumes are selected by the utility, but volumes are typically 10 L [2.64 gal] to 50 L [13.2 gal] and preferred to be consistent between sampling events for each source) is reached, remove tubing from the carboy and then shut off the

• Record the following information on the capsule label and/or sample collection form:

Stop time (when the pump was shut off)

Final meter reading

Comments to laboratory, if needed

• With the capsule inlet pointed up, loosen the outlet end of the Envirochek™ /Envirochek™ HV capsule and allow water to drain as much as possible. Water drainage from the capsule through the outlet is acceptable, as the sample has passed through the membrane. Opening the bleed valve during the draining will speed the process. Be sure to close the valve when

• Disconnect the inlet end of the Envirochek™ /Envirochek™ HV capsule, making sure not to spill any of the water remaining in the capsule through the inlet port. This water is part of your sample. Capsule may be shipped with or without residual

• Seal the inlet of the capsule with the vinyl end cap that was saved

• Seal the outlet of the capsule with the vinyl end cap that was saved previously. Place the Envirochek™ /Envirochek™ HV capsule in a plastic ziplock bag for

• Immediately following sample collection, place the bag containing the capsule in a refrigerator to chill prior to packing the shipping cooler for shipment. If no refrigerator is available, and the sample will not be shipped for several hours, place the bag in the shipping cooler with ice to chill. Replace the ice before

Note!   Method 1622/1623 requires that the temperature of the sample upon arrival at the laboratory must be #20°C (but not frozen), and the laboratory must begin sample processing within 96 hours of sample collection. If the sample temperature and holding time requirements are not met, then the sample is invalid and must be recollected.

3.0                     Packing the Sample

• Insert two large plastic trash bags into the shipping cooler to create a double liner. Immediately before packing the cooler, create two 4-pound bags of ice in two separate ziplock bags. To prevent leaks place each ice pack into an additional ziplock bag. Gel packs or blue ice may be used instead of wet ice, as long as the sample is maintained in the appropriate temperature Seal the ziplock bags, expelling as much air as possible, and secure top with tape.

Note!   Shipping companies may delay sample shipments if leakage occurs. Double liners and ziplock bags around ice will prevent leakage and delays.

• Place the bag containing the capsule into the shipping container. Wrap the capsule in bubble wrap to prevent freezing. Inflated, empty sample bags can be placed between the capsule and the ice packs to prevent the sample from

• If you will be monitoring sample temperature during shipment, place in the cooler the temperature monitoring device (e.g., extra sample bottle for measuring sample temperature upon receipt at the laboratory, thermometer vial, or Thermochron™ iButton). Seal each liner bag by twisting top of bag and tying in a

• Peel the backing off one of the plastic airbill sleeves and attach the sleeve to the inside of the cooler

Sign and date the sample collection form.

Fold the completed sample collection form, and place it inside the plastic sleeve.

• Close the cooler lid, seal the horizontal joints with strapping tape, and secure the lid with tape by taping the cooler at each end, perpendicular to the

Note!   Shipping companies may delay sample shipments if leakage occurs. Be sure to seal the cooler joints.

• Peel the backing off of the second airbill sleeve and attach the sleeve to the outside of the cooler lid. Complete the shipping airbill with the laboratory address, billing information, sample weight, and shipping service. Remove the shipper’s copy of the airbill, and place the remainder of the airbill inside the plastic

4.0                     Shipping and Tracking

• Ship samples on the day of collection and use a reliable shipping service for overnight delivery. If samples are not shipped the day of collection, the sample must be maintained between 1°C and 10°C (but not frozen) by chilling in a refrigerator or cooler filled with

• Contact the laboratory to notify them of the sample shipment. Request that the laboratory contact you the next day if the sample is not

• Using the airbill number on the shipper’s copy of the airbill, track the sample shipment using the shipping company’s web page or by contacting the shipping company over the

• If problems are encountered with the shipment, communicate with the shipping company to resolve, and update the laboratory regarding the status of the

Original PDF from EPA

In the past 30 years, the Safe Drinking Water Act (SDWA) has been highly effective in protecting public health and has also evolved to respond to new and emerging threats to safe drinking water. Disinfection of drinking water is one of the major public health advances in the 20th century. One hundred years ago, typhoid and cholera epidemics were common through American cities; disinfection was a major factor in reducing these epidemics.

In the past 15 years, we have learned that there are specific microbial pathogens, such as Cryptosporidium, which can cause illness, and are highly resistant to traditional disinfection practices. We also know that the disinfectants themselves can react with naturally-occurring materials in the water to form byproducts, which may pose health risks.

Amendments to the SDWA in 1996 require EPA to develop rules to balance the risks between microbial pathogens and disinfection byproducts (DBPs). The Stage 1 Disinfectants and Disinfection Byproducts Rule and Interim Enhanced Surface Water Treatment Rule, promulgated in December 1998, were the first phase in a rulemaking strategy required by Congress as part of the 1996 Amendments to the Safe Drinking Water Act.

The Long Term 2 Enhanced Surface Water Treatment Rule builds upon earlier rules to address higher risk public water systems for protection measures beyond those required for existing regulations.

The Long Term 2 Enhanced Surface Water Treatment Rule and the Stage 2 Disinfection Byproduct Rule are the second phase of rules required by Congress. These rules strengthen protection against microbial contaminants, especially Cryptosporidium, and at the same time, reduce potential health risks of DBPs.

Questions and Answers

What is the LT2ESWTR?

The purpose of Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) is to reduce illness linked with the contaminant Cryptosporidium and other pathogenic microorganisms in drinking water. The LT2ESWTR will supplement existing regulations by targeting additional Cryptosporidium treatment requirements to higher risk systems. This rule also contains provisions to reduce risks from uncovered finished water reservoirs and provisions to ensure that systems maintain microbial protection when they take steps to decrease the formation of disinfection byproducts that result from chemical water treatment.

Current regulations require filtered water systems to reduce source water Cryptosporidium levels by 2-log (99 percent). Recent data on Cryptosporidium infectivity and occurrence indicate that this treatment requirement is sufficient for most systems, but additional treatment is necessary for certain

higher risk systems. These higher risk systems include filtered water systems with high levels of Cryptosporidium in their water sources and all unfiltered water systems, which do not treat for

Cryptosporidium.

The LT2ESWTR is being promulgated simultaneously with the Stage 2 Disinfection Byproduct Rule to address concerns about risk tradeoffs between pathogens and DBPs.

What are the health risks of Cryptosporidium?

Cryptosporidium is a significant concern in drinking water because it contaminates most surface waters used as drinking water sources, it is resistant to chlorine and other disinfectants, and it has caused waterborne disease outbreaks. Consuming water with Cryptosporidium can cause gastrointestinal illness, which may be severe and sometimes fatal for people with weakened immune systems (which may include infants, the elderly, and people who have AIDS).

Who must comply with this rule?

This regulation will apply to all public water systems that use surface water or ground water under the direct influence of surface water.

What does the rule require?

Monitoring: Under the LT2ESWTR, systems will monitor their water sources to determine treatment requirements. This monitoring includes an initial two years of monthly sampling for Cryptosporidium. To reduce monitoring costs, small filtered water systems will first monitor for E. coliCa bacterium which is less expensive to analyze than CryptosporidiumCand will monitor for Cryptosporidium only if their E. coli results exceed specified concentration levels.

Monitoring starting dates are staggered by system size, with smaller systems beginning monitoring after larger systems. Systems must conduct a second round of monitoring six years after completing the initial round to determine if source water conditions have changed significantly. Systems may use (grandfather) previously collected data in lieu of conducting new monitoring, and systems are not required to monitor if they provide the maximum level of treatment required under the rule.

Cryptosporidium treatment: Filtered water systems will be classified in one of four treatment categories (bins) based on their monitoring results. The majority of systems will be classified in the lowest treatment bin, which carries no additional treatment requirements. Systems classified in higher treatment bins must provide 90 to 99.7 percent (1.0 to 2.5-log) additional treatment for Cryptosporidium. Systems will select from a wide range of treatment and management strategies in the Amicrobial toolbox@ to meet their additional treatment requirements. All unfiltered water systems must provide at least 99 or 99.9 percent (2 or 3-log) inactivation of Cryptosporidium, depending on the results of their monitoring. These Cryptosporidium treatment requirements reflect consensus recommendations of the Stage 2 Microbial and Disinfection Byproducts Federal Advisory Committee.

Other requirements: Systems that store treated water in open reservoirs must either cover the reservoir or treat the reservoir discharge to inactivate 4-log virus, 3-log Giardia lamblia, and 2-log Cryptosporidium. These requirements are necessary to protect against the contamination of water that occurs in open reservoirs. In addition, systems must review their current level of microbial treatment before making a significant change in their disinfection practice. This review will assist systems in maintaining protection against microbial pathogens as they take steps to reduce the formation of disinfection byproducts under the Stage 2 Disinfection Byproducts Rule, which EPA is finalizing along with the LT2ESWTR.

What are the benefits of the rule?

The LT2ESWTR will improve the control of Cryptosporidium and other microbiological pathogens in drinking water water systems with the highest risk levels. EPA estimates that full compliance with the LT2ESWTR will reduce the incidence of cryptosporidiosis – the gastrointestinal illness caused by ingestion of Cryptosporidium – by 89,000 to 1,459,000 cases per year, with an associated reduction of 20 to 314 premature deaths. The monetized benefits associated with these reductions ranges from $253 million to $1.445 billion per year. The additional Cryptosporidium treatment requirements of the LT2ESWTR will also reduce exposure to other microbial pathogens, such as Giardia, that co-occur with Cryptosporidium. Additional protection from microbial pathogens will come from provisions in this rule for reviewing disinfection practices and for covering or treating uncovered finished water reservoirs, though EPA has not quantified these benefits.

What are the costs of the rule?

The LT2ESWTR will result in increased costs to public water systems and states. The average annualized present value costs of the LT2ESWTR are estimated to range from $92 to $133 million (using a three percent discount rate). Public water systems will bear approximately 99 percent of this total cost, with states incurring the remaining 1 percent. The average annual household cost is estimated to be $1.67 to $2.59 per year, with 96 to 98 percent of households experiencing annual costs of less than $12 per year.

What technical information will be available on the rule?

The following guidance documents will be available:

• • Source Water Monitoring Guidance

• • Microbial Laboratory Guidance

• • Small Entity Compliance Guidance

• • Microbial Toolbox Guidance Manual

• • Ultraviolet Disinfection Guidance Manual

• • Membrane Filtration Guidance Manual

• • Simultaneous Compliance Guidance Manual

• • Low-pressure Membrane Filtration for Pathogen Removal: Application, Implementation, and Regulatory Issues

Where can I find more information about this notice and the LT2ESWTR?

For general information on the LT2ESWTR, contact the Safe Drinking Water Hotline at (800) 426-4791. The Safe Drinking Water Hotline is open Monday through Friday, excluding legal holidays, from 10:00 a.m. to 4:00 p.m., Eastern time. For copies of the Federal Register notice of the regulation or technical fact sheets, visit the EPA Safewater website at  http://www.epa.gov/safewater/disinfection/lt2. For technical inquiries, email  stage2mdbp@epa.gov.

Office of Water (4607M) EPA 815-F-05-009 December 2005   www.epa.gov/safewater