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Part 1B substances have significant environmental and human health impacts at relatively low levels. They occur naturally in the environment, but human activities can concentrate them to toxic levels. Because minimal releases of Part 1B substances may result in significant adverse effects, the reporting thresholds for Part 1B substances are lower than those for Part 1A substances. As such, these substances are commonly referred to as the “alternate threshold substances.”

5.1    Reporting Criteria for Part 1B Substances

In general, any person who owns or operates a contiguous facility, a portable facility, or an offshore installation must submit a report for a Part 1B substance if both of the following criteria are met:

1. employees work a total of ≥ 20 000 hours, or activities to which the employee threshold does not apply (see Table 3) take place at the facility, and
2. the total amount of the Part 1B substance

• manufactured, processed or otherwise used, plus
• incidentally manufactured, processed or otherwise used as a by-product, plus
• contained in tailings disposed of during the calendar year, plus
• contained in waste rock that is not clean or inert (see section 3.7.4) disposed of during the calendar year

at the concentrations specified in Table 12, is greater than or equal to the mass threshold specified in Table 12.

Figure 3 illustrates the steps for determining if a report for Part 1B substances is required.

Table 12. Concentration and Mass Thresholds for Part 1B Substances

Substance	Occurrence of the Substance	Concentration Threshold (by Weight)	Mass Threshold (kg)
Mercury	manufactured, processed or otherwise used	any concentration	5
	incidentally manufactured, processed or otherwise used
	contained in tailings disposed of during the calendar year
	contained in waste rock disposed of during the calendar year
Cadmium	manufactured, processed or otherwise used	0.1% or more	5
	incidentally manufactured, processed or otherwise used	any concentration
	contained in tailings disposed of during the calendar year
	contained in waste rock disposed of during the calendar year
Arsenic Hexavalent chromium Lead Tetraethyl lead	manufactured, processed or otherwise used	0.1% or more	50
	incidentally manufactured, processed or otherwise used	any concentration
	contained in tailings disposed of during the calendar year
	contained in waste rock disposed of during the calendar year
Selenium	manufactured, processed or otherwise used	0.000005% or more	100
	incidentally manufactured, processed or otherwise used	any concentration
	contained in tailings disposed of during the calendar year
	contained in waste rock disposed of during the calendar year

Figure 3. Reporting for Part 1B Substances

5.1.1     Part 1B Substance Qualifiers

Mercury, cadmium, arsenic, hexavalent chromium, lead and selenium are listed with the qualifier “and its compounds.” The pure element and any compound, alloy or mixture of any Part 1B substance must be reported as the equivalent weight of the metal itself. For example, if potassium dichromate (K₂Cr₂O₇, molecular weight = 294 grams per mole [g/mol]) is used, only the mass contribution of hexavalent chromium (2 × 52 g/mol) in K₂Cr₂O₇ should be included in the threshold calculation for hexavalent chromium.

Note that lead has an additional qualifier: the lead contribution from tetraethyl lead, stainless steel, brass and bronze alloys should be excluded from threshold calculations for lead. Tetraethyl lead should be treated as a pure compound. If required, separate reports should be submitted for lead (and its compounds) and tetraethyl lead, with the reporting criteria applied to each substance separately.

5.2    Calculating the Reporting Threshold for Part 1B Substances

When calculating the reporting threshold, include the quantity of a Part 1B substance that is:

• manufactured at a concentration equal to or greater than the concentration threshold (if any);
• processed at a concentration equal to or greater than the concentration threshold (if any);
• otherwise used at a concentration equal to or greater than the concentration threshold (if any);
• a by-product, at any concentration, released on-site to the environment or disposed of on- or off-site;
• contained in tailings disposed of during the calendar year, at any concentration; and
• contained in waste rock disposed of during the calendar year, at any concentration.

Do not include quantities of a Part 1B substance contained in any of the sources that should not be considered, as listed in Table 4.

As noted previously, quantities of substances disposed of in inert or clean waste rock do not need to be included in threshold calculations. However, the quantity of arsenic contained in inert or clean waste rock can be excluded only if the concentration of arsenic is < 12 mg/kg of waste rock.

5.3    Calculating Releases, Disposals and Transfers for Recycling of Part 1B Substances

If the reporting threshold for a Part 1B substance is met (as discussed in section 5.2), a subsequent calculation is required to determine the quantities of that substance that are released, disposed of and transferred for recycling. If the reporting threshold is met, all releases, disposals and transfers for recycling of that substance must be reported, regardless of their concentration or quantity and regardless of whether or not the quantity is used in the threshold calculation.

5.4    Reporting Releases, Disposals and Transfers for Recycling of Part 1B Substances

All releases, disposals and transfers for recycling of Part 1B substances must be reported in kilograms (kg).

Note that even if on-site releases, disposals or off-site transfers for recycling are zero, a report must be submitted for a Part 1B substance once the mass reporting threshold has been met.

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Polycyclic aromatic hydrocarbons (PAHs) may be used as commercial chemicals, incidentally manufactured in certain industrial processes, or contained in tailings. There are 29 PAHs listed in Part 2 of the NPRI substance list.  For a list of these PAHs, consult the NPRI website.

6.1    Reporting Criteria for Part 2 Substances

With the exception of facilities where wood preservation using creosote takes place (see below), reporting for PAHs is based on the quantities of PAHs that are released, disposed of or transferred for recycling as a result of incidental manufacture or from the generation of tailings. A person who owns or operates a contiguous facility, a portable facility, or an offshore installation must submit reports for PAHs if both of the following criteria are met:

1. employees work a total of ≥ 20 000 hours, or activities to which the employee threshold does not apply (listed in Table 3) take place at the facility; and
2. the sum of all PAHs released, disposed of or transferred off-site for recycling as a result of incidental manufacture and/or as a result of the generation of tailings is ≥ 50 kg.

Wood preservation facilities using creosote must report for Part 2 substances, regardless of quantities and regardless of the number of hours worked by employees. See section 3.6.2 and the Guidance for Wood Preservation Facilities Reporting to the NPRI (www.ec.gc.ca/inrp-npri/default.asp?lang=En&n=29B3E589-1) for more information.

Figure 4 illustrates the steps for determining if reports for Part 2 substances are required, and, if so, what information must be reported.

6.2    Calculating the Reporting Threshold for Part 2 Substances

The sum of the quantities of individual PAHs incidentally manufactured and/or contained in tailings disposed of during the calendar year should be compared to the 50 kg threshold. In some cases, only information on unspeciated PAHs may be available, or a combination of information on individual and unspeciated PAHs may be available. Add the quantities of each individual PAH and the quantity of unspeciated PAHs to determine if the 50 kg reporting threshold is met.

Do not include anthracene (CAS RN 120-12-7) and naphthalene (CAS RN 91-20-3) when determining the reporting threshold for PAHs. Although anthracene and naphthalene are PAHs, they are NPRI Part 1A substances. Therefore, they are subject to Part 1A reporting requirements.

Figure 4. Reporting for Part 2 Substances

6.3    Reporting Releases, Disposals and Transfers for Recycling of Part 2 Substances

All releases, disposals and transfers for recycling of Part 2 substances must be reported in kilograms.

Releases, disposals and transfers for recycling must be reported for the individual PAHs, even though the 50 kg threshold applies to the aggregate total of all 29 PAHs. Depending on the information that is available, there are three ways to report PAHs (illustrated in Figure 4 and summarized in Table 13). If the 50 kg threshold is met, or if wood preservation using creosote takes place at the facility, and information on releases, disposals and transfers for recycling for individual PAHs is available, those PAHs that are incidentally manufactured and released, disposed of or transferred for recycling in amounts ≥ 5 kg must be reported individually.

If only a combination of information on individual and total PAHs is available, quantities of individual PAHs in amounts ≥ 5 kg and quantities of “total unspeciated PAHs” should both be reported. If the only available information is for total PAHs, total unspeciated PAHs should be reported.

Note that total unspeciated PAHs does not mean the sum of the 29 individual PAHs. In order to avoid double‑counting when reporting both individual and total unspeciated PAHs, the quantities of individual PAHs that are reported separately should not be included in the quantity reported for total unspeciated PAHs. In addition, do not include release, disposal and transfer for recycling quantities of the two PAHs listed in Part 1A (anthracene and naphthalene) when reporting for total PAHs.

Facilities using creosote for wood preservation must report for PAHs regardless of the quantity of PAHs released, disposed of or transferred for recycling or the number of hours worked by employees. Depending on the information available to the facility, reports can be submitted for: individual PAHs released, disposed of or transferred for recycling in quantities ≥ 5 kg; a combination of individual PAHs in quantities ≥ 5 kg and total PAHs; or total PAHs.

Table 13. How to Report Polycyclic Aromatic Hydrocarbons

Type of information available	Comparison to thresholds	What to report
Quantities of individual PAHs	Add quantities of individual PAHs If the total is ≥ 50 kg, reporting is required	Report quantities of individual PAHs that are incidentally manufactured and released, disposed of or transferred for recycling in quantities ≥ 5 kg Quantities of individual PAHs that are < 5 kg are not required to be reported
Combination of quantities of individual PAHs and quantity of total PAHs	Add quantities of individual and total PAHs If the total is ≥ 50 kg, reporting is required	Report quantities of individual PAHs that are ≥ 5 kg, and Report total unspeciated PAHs (not including quantities of individual PAHs) Quantities of individual PAHs that are < 5 kg are not required to be reported
Quantity of total PAHs	If total PAHs are ≥ 50 kg, reporting is required	Report total unspeciated PAHs