25 Pa. Code § 109.1
The following words and terms, when used in this chapter, have the following meanings, unless the context clearly indicates otherwise:
ANSI-The American National Standards Institute, Inc. of New York, New York.
Act-The Pennsylvania Safe Drinking Water Act (35 P. S. §§ 721.1-721.17).
Administrator-The Administrator of the EPA.
BAT-Best Available Technology-The best technology, treatment techniques or other means which the Administrator finds are available for achieving compliance with maximum contaminant levels. This chapter incorporates by reference the BAT specified in 40 CFR Parts 141 and 142 (relating to National primary drinking water regulations; and National primary drinking water regulations implementation).
Bag filter-A pressure-driven separation device that removes particulate matter larger than 1 micrometer using an engineered porous filtration media. It is typically constructed of a nonrigid, fabric filtration media housed in a pressure vessel in which the direction of flow is from the inside of the bag to outside.
Bank filtration-A water treatment process that uses a well to recover surface water that has naturally infiltrated into groundwater through a riverbed or bank. Infiltration is typically enhanced by the hydraulic gradient imposed by a nearby pumping water supply or other well.
Bin-A category based on the level of Cryptosporidium present in source water. Four potential bins exist, 1-4. The higher the bin, the higher the concentration of source water Cryptosporidium.
Bottled water system-A public water system which provides water for bottling in sealed bottles or other sealed containers. The term includes, but is not limited to, the sources of water and treatment, storage, bottling, manufacturing and distribution facilities. The term does not include a public water system which provides only a source of water supply for a bottled water system and excludes an entity providing only transportation, distribution or sale of bottled water in sealed bottles or other sealed containers.
Bulk water hauling system-A public water system which provides water piped into a carrier vehicle and withdrawn by a similar means into the user's storage facility or vessel. The term includes, but is not limited to, the sources of water, treatment, storage or distribution facilities. The term does not include a public water system which provides only a source of water supply for a bulk water hauling system.
CASRN-Chemical Abstracts Service Registry Number.
CCR-Consumer Confidence Report-An annual water quality report that community water systems deliver to their customers, as described in § 109.416 (relating to CCR requirements).
CPE-Comprehensive performance evaluation-A thorough review and analysis of a treatment plant's performance-based capabilities and associated administrative, operation and maintenance practices.
CT-The product of residual disinfectant concentration (C) measured in mg/L in a representative sample of water prior to the first customer, and disinfectant contact time (T); that is, "C" x "T." If disinfectants are applied at more than one point prior to the first customer, the CT is determined for each disinfectant sequence prior to the first customer to determine the total percent inactivation achieved by disinfection prior to the first customer. In determining the total percent inactivation, the residual disinfectant concentration of each disinfection sequence and corresponding contact time before subsequent disinfection application points shall be determined.
Cartridge filter-A pressure-driven separation device that removes particulate matter larger than 1 micrometer using an engineered porous filtration media. It is typically constructed as rigid or semirigid, self-supporting filter elements housed in pressure vessels in which flow is from the outside of the cartridge to the inside.
Coagulation-A process using coagulant chemicals and mixing by which colloidal and suspended material are destabilized and agglomerated into settleable or filterable flocs, or both.
Collection-The parts of a public water system occurring prior to treatment, including source, transmission facilities and pretreatment storage facilities.
Combined distribution system-The interconnected distribution system consisting of the distribution systems of wholesale systems and of the public water systems that obtain finished water from another public water system.
Community water system-A public water system which serves at least 15 service connections used by year-round residents or regularly serves at least 25 year-round residents.
Compliance cycle-A 9-year calendar year cycle during which public water suppliers shall monitor for contaminants. The first compliance cycle begins January 1, 1993, and ends December 31, 2001.
Compliance period-A 3-year calendar year period within a compliance cycle. Each compliance cycle is made up of three 3-year compliance periods. Within the first compliance cycle, the first compliance period runs from January 1, 1993, through December 31, 1995.
Confluent growth-Bacterial growth, with or without sheen, covering the entire membrane filter, or a portion thereof, in which bacterial colonies are not discrete.
Consecutive water system -A public water system which obtains all of its water from another public water system and resells the water to a person, provides treatment to meet a primary MCL, MRDL or treatment technique, or provides drinking water to an interstate carrier. The term does not include bottled water and bulk water systems.
Contaminant-A physical, chemical, biological or radiological substance or matter in water.
Conventional filtration-The series of processes for the purpose of substantial particulate removal consisting of coagulation, flocculation, clarification, and granular media filtration. The clarification step must be a solid/liquid separation process where accumulated solids are removed during this separate component of the treatment system.
Corrosion inhibitor-A substance capable of reducing the corrosivity of water toward metal plumbing materials, especially lead and copper, by forming a protective film on the interior surface of those materials.
Cross-connection-An arrangement allowing either a direct or indirect connection through which backflow, including backsiphonage, can occur between the drinking water in a public water system and a system containing a source or potential source of contamination, or allowing treated water to be removed from any public water system, used for any purpose or routed through any device or pipes outside the public water system, and returned to the public water system. The term does not include connections to devices totally within the control of one or more public water systems and connections between water mains.
DBP-Disinfection byproduct.
Diatomaceous earth filtration-A process for the purpose of substantial particulate removal in which a precoat cake of diatomaceous earth filter media is deposited on a support membrane (septum), and while the water is filtered by passing through the cake on the septum, additional filter media, known as body feed, is continuously added to the feed water, to maintain the permeability of the filter cake.
Direct filtration-A series of processes for the purpose of substantial particulate removal consisting of coagulation and filtration. The term normally includes flocculation after coagulation, but does not include sedimentation.
Disinfectant contact time-The time in minutes that it takes for water to move from the point of disinfectant application to the point where residual disinfectant concentration is measured. Contact time in pipelines is calculated based on plug flow by dividing the internal volume of the pipeline by the flow rate through that pipeline. Contact time within mixing basins and storage reservoirs is determined by tracer studies or an equivalent demonstration. Guidance for making these determinations appears in the "Guidance Manual for Compliance with the Filtration and Disinfection Requirements for Public Water Systems Using Surface Water Sources" (U. S. EPA, Office of Drinking Water, Criteria and Standards Division).
Disinfection-A process which inactivates pathogenic organisms in water by chemical oxidants or equivalent agents, such as ultraviolet light.
Disinfection profile-The summary of daily Giardia lamblia inactivation through the treatment plant as determined through procedures and measurement methods established by this chapter.
Dual sample set-A set of two samples collected at the same time and same location, with one sample analyzed for TTHM and the other sample analyzed for HAA5. Dual sample sets are collected for the purposes of conducting an IDSE and determining compliance with the TTHM and HAA5 MCLs under Subchapter G (relating to system management responsibilities).
Enhanced coagulation-The addition of sufficient coagulant for improved removal of disinfection byproduct precusors by conventional filtration treatment.
Enhanced softening-The improved removal of disinfection byproduct precusors by precipitative softening.
Entry point-A point acceptable to the Department at which finished water representative of each source enters the distribution system.
Environmental acts-The Clean Streams Law (35 P. S. §§ 691.1-691.1001), the Air Pollution Control Act (35 P. S. §§ 4001-4015), the Radiation Protection Act (35 P. S. §§ 7110.101-7110.703), the Surface Mining Conservation and Reclamation Act (52 P. S. §§ 1396.1-1396.31), the Noncoal Surface Mining Conservation and Reclamation Act (52 P. S. §§ 3301-3326), section 1917-A of The Administrative Code of 1929 (71 P. S. § 510-17), the Dam Safety and Encroachment Act (32 P. S. §§ 693.1-693.27), the Solid Waste Management Act (35 P. S. §§ 6018.101-6018.1003), the Plumbing System Lead Ban and Notification Act (35 P. S. §§ 723.1-723.17) and any other State or Federal statutes relating to environmental protection or to the protection of the public health, safety and welfare.
Facility-A part of a public water system used for collection, treatment, storage or distribution of drinking water.
Federal act-The Safe Drinking Water Act (42 U.S.C.A. §§ 300f - 300j - 10).
Federal regulations-The National Primary Drinking Water Regulations and the National Secondary Drinking Water Regulations.
Filter profile-A graphical representation of individual filter performance, based on continuous turbidity measurements or total particle counts versus time for an entire filter run, from startup to backwash inclusively, that includes an assessment of filter performance while another filter is being backwashed.
Filtration-A process for removing particulate matter from water by passage through porous media.
Finished water-Water that is introduced into the distribution system of a public water system and is intended for distribution and consumption without further treatment, except as necessary to maintain water quality in the distribution system (for example, booster disinfection or addition of corrosion control chemicals).
First-draw sample-A 1-liter sample of tap water collected in accordance with § 109.1103 (relating to monitoring requirements), that has been standing in plumbing pipes at least 6 hours and is collected without flushing the tap.
Flocculation-A process to enhance agglomeration or collection of smaller floc particles into larger, more easily settleable or filterable particles through gentle stirring by hydraulic or mechanical means.
Flowing stream-A course of running water flowing in a definite channel.
GAC-Granular Activated Carbon-A highly porous adsorbent carbon material produced by heating organic matter that can absorb various dissolved chemicals in the water.
GAC10-A granular activated carbon filter bed with an empty bed contact time of 10 minutes based on average daily flow and a carbon reactivation frequency of every 180 days, except that the reactivation frequency for GAC10 used as a BAT shall be 120 days.
GAC20-A granular activated carbon filter bed with an empty bed contact time of 20 minutes based on average daily flow and a carbon reactivation frequency of every 240 days.
GUDI-Groundwater under the direct influence of surface water-
Groundwater-Water that is located within the saturated zone below the water table and is available to supply wells and springs.
HAA5-Haloacetic acids (five)-The sum of the concentrations in milligrams per liter of the haloacetic compounds (monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid), rounded to two significant figures after addition.
IBWA-The International Bottled Water Association, Alexandria, Virginia 22314.
IDSE-Initial Distribution System Evaluation.
IOC-Inorganic chemical.
Initial compliance period-The first full 3-year compliance period during which a public water supply is required to monitor for a contaminant.
Innovative technology-A method, process or equipment for the treatment of drinking water which is not designated as BAT under EPA regulations and the effectiveness of which has not been commercially demonstrated in the water supply industry.
LRAA-Locational running annual average-The average, computed quarterly, of quarterly arithmetic averages of all analytical results for samples taken at a particular monitoring location during the most recent 4 calendar quarters.
Lake/reservoir-A natural or man made basin or hollow on the earth's surface in which water collects or is stored that may or may not have a current or single direction of flow.
Lead service line-A service line made of lead which connects a water main to a building inlet and a lead pigtail, gooseneck or other fitting which is connected to the lead line.
Level 1 assessment-An evaluation to identify the possible presence of sanitary defects, defects in distribution system coliform monitoring practices and, when possible, the likely reason that the system triggered the assessment.
Level 2 assessment-An evaluation to identify the possible presence of sanitary defects, defects in distribution system coliform monitoring practices and, when possible, the likely reason that the system triggered the assessment. This assessment provides a more detailed examination of the system, including the system's monitoring and operational practices, than does a Level 1 assessment through the use of more comprehensive investigation and review of available information, additional internal and external resources, and other relevant practices.
Liquid from dewatering processes-A stream containing liquids generated from a unit used to concentrate solids for disposal.
Log inactivation-A measure of the amount of viable microorganisms that are rendered nonviable during disinfection processes and is defined as:
Log inactivation = log
Where,
No = Initial concentration of viable microorganisms
ND = Concentration of viable microorganisms after disinfection
Log = Logarithm to base 10
Log inactivation is related to percent inactivation, defined as:
Percent inactivation =
Common log-inactivation values and corresponding percent inactivation values include:
| Log Inactivation | Percent Inactivation |
| 0.5-log | 68.4% |
| 1.0-log | 90.0% |
| 1.5-log | 96.8% |
| 2.0-log | 99.0% |
| 2.5-log | 99.7% |
| 3.0-log | 99.9% |
| 4.0-log | 99.99% |
Log removal-A measure of the physical removal of a targeted contaminant or disease-causing microorganism (or its surrogate) during water treatment processes and is defined as:
Log removal = log
Where,
No = Initial concentration of targeted contaminant or disease-causing microorganism (or its surrogate)
NR = Concentration of targeted contaminant or disease-causing microorganism (or its surrogate) after removal
Log = Logarithm to base 10
Log removal is related to percent removal, defined as:
Percent removal =
Common log removal values and corresponding percent removal values include:
| Log Removal | Percent Removal |
| 0.5-log | 68.4% |
| 1.0-log | 90.0% |
| 1.5-log | 96.8% |
| 2.0-log | 99.0% |
| 2.5-log | 99.7% |
| 3.0-log | 99.9% |
| 4.0-log | 99.99% |
Log treatment-A measure of the removal or inactivation, or Department-approved combination of removal and inactivation, of a targeted contaminant or disease-causing microorganism (or its surrogate) during water treatment processes and is defined as:
Log treatment = Log removal + Log inactivation
Or,
Log treatment = log
Where,
No = Initial concentration of a targeted contaminant or disease-causing microorganism (or its surrogate)
NT = Concentration of a targeted contaminant or disease-causing microorganism (or its surrogate) after treatment
Log = Logarithm to base 10
Log treatment is related to percent treatment, defined as:
Percent treatment =
Common log treatment values and corresponding percent treatment values include:
| Log Treatment | Percent Treatment |
| 0.5-log | 68.4% |
| 1.0-log | 90.0% |
| 1.5-log | 96.8% |
| 2.0-log | 99.0% |
| 2.5-log | 99.7% |
| 3.0-log | 99.9% |
| 4.0-log | 99.99% |
MCL-Maximum Contaminant Level-The maximum permissible level of a contaminant in water which is delivered to a user of a public water system, and includes the primary and secondary MCLs established under the Federal act, and MCLs adopted under the act.
MCLG-Maximum Contaminant Level Goal-
MDL-Method Detection Limit-The minimum measured concentration of a substance that can be reported with 99% confidence that the measured concentration is distinguishable from method blank results.
MRDL-Maximum Residual Disinfectant Level-The maximum permissible level of a disinfectant added for water treatment that may not be exceeded at the consumer's tap without an unacceptable possibility of adverse health effects. The consumer's tap means the entry point for bottled water and vended water systems, retail water facilities and bulk water hauling systems.
MRL-Minimum Reporting Level-The minimum quantitation limit that can practically and consistently be achieved, with 95% confidence, by capable analysts at 75% or more of laboratories using a specified analytical method.
Membrane filtration-
Microorganism-Any of a number of unicellular, multicellular or colonial bacteria, fungi, protozoa, archaea or viruses whose individuals are too small to be seen by the human eye without magnification.
NAMA-The National Automatic Merchandising Association of Chicago, Illinois.
NSF-NSF International, Ann Arbor, Michigan 48105.
NTU-Nephelometric Turbidity Unit.
National Primary Drinking Water Regulations-Primary drinking water regulations and implementation regulations promulgated by the Administrator under the Federal act at 40 CFR Parts 141 and 142 (relating to national primary drinking water regulations; and national primary drinking water regulations implementation). The term includes interim, revised and final regulations.
National Secondary Drinking Water Regulations-Secondary drinking water regulations promulgated by the Administrator under the Federal act in 40 CFR 143.1 - 143.4.
New source-A source of water supply that is not covered by a valid permit issued under the act of April 22, 1905 ( P. L. 260, No. 182) (35 P. S. §§ 711-716) (Repealed) or under this chapter as a regular source of supply for the public water system.
Noncommunity water system-A public water system which is not a community water system.
Nontransient noncommunity water system -A noncommunity water system that regularly serves at least 25 of the same persons over 6 months per year.
PDWEP-Guidelines for Public Drinking Water Equipment Performance issued by NSF.
PFAS-Perfluoroalkyl and polyfluoroalkyl substances.
PFOA-Perfluorooctanoic acid-CASRN 335-67-1.
PFOS-Perfluorooctanesulfonic acid-CASRN 176323-1.
Performance evaluation sample-A reference sample provided to a laboratory for the purpose of demonstrating that the laboratory can successfully analyze the sample within the limits of performance specified by the Department. The true value of the concentration of the reference material is unknown to the laboratory at the time of the analysis.
Person-An individual, partnership, association, company, corporation, municipality, municipal authority, political subdivision, or an agency of Federal or State government. The term includes the officers, employees and agents of a partnership, association, company, corporation, municipality, municipal authority, political subdivision, or an agency of Federal or State government.
Plant intake-The works or structures at the head of a conduit through which water is diverted from a source (for example, a river or lake) into the treatment plant.
Point-of-entry (POE) device-A treatment device used as an alternative to central treatment that is installed on a public water line or service connection to a house, building or other facility for the purpose of reducing contaminants in the water distributed throughout the house, building or facility.
Presedimentation-A preliminary treatment process used to remove gravel, sand and other particulate material from the source water through settling before the water enters the primary clarification and filtration processes in a treatment plant.
Public water supplier-A person who owns or operates a public water system.
Public water system-A system which provides water to the public for human consumption which has at least 15 service connections or regularly serves an average of at least 25 individuals daily at least 60 days out of the year. The term includes collection, treatment, storage and distribution facilities under control of the operator of the system and used in connection with the system. The term includes collection or pretreatment storage facilities not under control of the operator which are used in connection with the system. The term also includes a system which provides water for bottling or bulk hauling for human consumption. Water for human consumption includes water that is used for drinking, bathing and showering, cooking, dishwashing or maintaining oral hygiene.
RAA-Running annual average-The average, computed quarterly, of quarterly arithmetic averages of all analytical results for samples taken during the most recent 4 calendar quarters.
Recycle-The act of returning recycle streams to a conventional or direct filtration plant's treatment process.
Recycle flows-Any water, solid or semi-solid generated by a conventional or direct filtration plant's treatment process and residual treatment processes that is returned to the plant's treatment process.
Reliably and consistently below the MCL-
Repeat compliance period-A subsequent compliance period after the initial compliance period.
Retail water facility-A public water system which provides water for bottling without the use of a water vending machine by dispensing unit servings of water in containers whether or not the containers are provided by the customers.
SOC-Synthetic Organic Chemical.
SUVA-Specific ultraviolet absorption at 254 nanometers (nm)-An indicator of the humic content of water. It is a calculated parameter obtained by dividing a sample's ultraviolet absorption at a wavelength of 254 nm (UV254) (in m-1) by its concentration of dissolved organic carbon (DOC) (in mg/L).
Sanitary defect-A defect that could provide a pathway of entry for microbial contamination into the distribution system or that is indicative of a failure or imminent failure in a barrier that is already in place.
Sanitary survey-An onsite review and evaluation of a public water system's source, facilities and equipment and the operation and maintenance procedures used by a public water supplier for producing and distributing safe drinking water.
Seasonal system-A noncommunity water system that is not operated as a public water system on a year-round basis and starts up and shuts down at the beginning and end of each operating season.
Sedimentation-A process for the removal of solids before filtration by gravity or separation.
Significant deficiency-A defect in design, operation or maintenance, or a failure or malfunction of the sources, treatment, storage or distribution system that the Department determines to be causing, or has the potential for causing the introduction of contamination into the water delivered to consumers.
Slow sand filtration-A process for the purpose of substantial particulate removal by physical and biological mechanisms during the passage of raw water through a bed of sand at low velocity-generally less than .4 meters per hour.
Source -The place from which water for a public water system originates or is derived, including, but not limited to, a well, spring, stream, reservoir, pond, lake or interconnection.
Source water assessment -An evaluation documented in writing of the contamination potential of a drinking water source used by a public water system which includes identifying the contributing area to the water source, an inventory of potential contaminant sources and a determination of the susceptibility of the water source to contamination.
Source water protection area -A surface water intake protection area or a wellhead protection area, or both.
Source water protection program -A surface water intake protection program or a wellhead protection program, or both.
Spent filter backwash water -A stream containing particles dislodged from filter media when the filter is backwashed to clean the filter.
Substantial modification -A change in a public water system that may affect the quantity or quality of water served to the public or which may be prejudicial to the public health or safety and includes the addition of new sources; the expansion of existing facilities; changes in treatment processes; addition, removal, renovation or substitution of equipment or facilities; and interconnections.
Surface water -Water open to the atmosphere or subject to surface runoff. The term does not include finished water.
Surface water intake protection area -The surface and subsurface area surrounding a surface-water intake supplying a public water system through which contaminants are reasonably likely to move toward and reach the water source. A surface water intake protection area must consist of up to three zones:
Surface water intake protection program -A comprehensive program designed to protect each surface water source used by a public water system from contamination.
System-
TOC-Total organic carbon-The total organic carbon in mg/L measured using heat, oxygen, ultraviolet irradiation, chemical oxidants or combinations of these oxidants that convert organic carbon to carbon dioxide, rounded to two significant figures.
TTHM-Total trihalomethanes-the sum of the concentrations in milligrams per liter of the trihalomethane compounds (trichloromethane, bromodichloromethane, dibromochloromethane and tribromomethane), rounded to two significant figures after addition.
Thickener supernatant-A stream containing the decant from a clarifier, sedimentation basin, or other unit used to treat water, solids or semi-solids from the primary treatment process.
Too numerous to count-Two hundred or more total bacterial colonies on a 47-mm diameter membrane filter.
Transient noncommunity water system-A public water system which is not a community, nontransient noncommunity, bottled or vended water system, nor a retail water facility or a bulk water hauling system.
Transmission-The movement of water from the source to a point of storage, treatment or distribution or from the point of treatment to the distribution system.
Treatment technique-A requirement which specifies a specific treatment method known to cause a reduction in the level of a contaminant which cannot practically be regulated by establishing an MCL. The term includes treatment technique requirements established under the Federal act, and treatment technique requirements adopted under the act.
2-stage lime softening-A process in which chemical addition and hardness precipitation occur in each of two distinct unit clarification processes in series prior to filtration.
Type of product-A particular kind of water for bottling characterized by its source or treatment process. Examples of the water include distilled water, mineral water, spring water and well water.
VOC-Volatile synthetic organic chemical.
Vended water system-A public water system which provides water for bottling through the use of one or more water vending machines.
Waterborne disease outbreak-An illness of the same etiology experienced by two or more persons and attributed to pathogenic organisms in which the public water system is implicated as the source of illness by the Department of Health.
Water for bottling-Artificial or natural mineral, spring or other water for bottling as drinking water.
Water vending machine-A self-contained, self-service device which, upon insertion of a coin, paper currency, token, card, key or other similar means or through manual operation, dispenses unit servings of water, either in bulk or in packages, without the necessity of replenishing the device between each vending operation.
Wellhead protection area -The surface and subsurface area surrounding a water well, well field, spring or infiltration gallery supplying a public water system, through which contaminants are reasonably likely to move toward and reach the water source. A wellhead protection area must consist of up to three zones:
Wellhead protection program -A comprehensive program designed to protect each well, spring or infiltration gallery used by a public water system from contamination.
Wholesale system -A public water system that treats source water as necessary to produce finished water and then delivers some or all of that finished water to another public water system. Delivery may be through a direct connection or through the distribution system of one or more public water systems.
25 Pa. Code § 109.1
The provisions of this § 109.1 amended under section 4 of the Pennsylvania Safe Drinking Water Act (35 P.S. § 721.4); and section 1920-A of The Administrative Code of 1929 (71 P.S. § 510-20).
This section cited in 25 Pa. Code § 78a.1 (relating to definitions); 25 Pa. Code § 109.202 (relating to State MCLs, MRDLs and treatment technique requirements); 25 Pa. Code § 109.301 (relating to general monitoring requirements); 25 Pa. Code § 109.407 (relating to general public notification requirements); 25 Pa. Code § 109.408 (relating to Tier 1 public notice-categories, timing and delivery of notice); 25 Pa. Code § 109.1204 (relating to requirements for microbial toolbox components); 25 Pa. Code § 273.115 (relating to geology and groundwater description); 25 Pa. Code § 277.115 (relating to geology and groundwater description); 25 Pa. Code § 288.122 (relating to geology and groundwater description); 25 Pa. Code § 289.122 (relating to geology and groundwater description); and 25 Pa. Code § 302.101 (relating to definitions).