Land Remediation

Yes. No exemptions are provided in the regulation for this situation.

No, such authorization is not required. However, before conducting work on or near sites with a history of activities that may have caused contamination, you should obtain the services of a qualified environmental consultant.

He or she would carry out the excavation and associated work and would also make appropriate enquiries including a review of the ministry's Site Registry and municipal records. If contamination is encountered during excavation you must provide a notification of commencement of independent remediation to the ministry.

Notifications of offsite migration are required only when a responsible person for a source site is conducting independent remediation or investigating a site. If either of these is occurring at the service station, we suggest that you contact the station owner again and notify them of this requirement. If that fails to produce results, we suggest that you notify the ministry at Site@gov.bc.ca.

Yes, the legislation is written such that the ministry makes a decision for the entire site, so information in the site profile would take into account all activities over the entire site.

Currently, most reserve land is under Federal jurisdiction and most requirements under the Environmental Management Act would not apply, including the requirement to submit a site profile. However, as treaties are established between bands and the Provincial Government, the provisions under EMA may apply. We expect that many First Nations will operate in a similar fashion to other local governments and will have to choose whether to opt out of the site profile process.

Landfilling of wastes is a Contaminated Sites Regulation Schedule 2 activity. When the landfill, permitted or not, no longer accepts waste this is considered decommissioning. At that time the owner or operator is required to submit a site profile directly to the ministry. Any landfill that has closed since April 1, 1997 should submit a site profile to the ministry advising of decommissioning, if they have not already done so.

The approval of a closure plan does not exempt the property owner from the duty to submit a site profile nor does it release a local government to issue an authorization specified in section 40(1) of EMA.

The ministry recommends that landfill closure and site remediation professionals work together to gather information that will satisfy both landfill closure plan requirements and a Certificate of Compliance for the site.

Many local governments have developed policy and bylaws that require site profiles be submitted when any authorizations are required from them. A municipality may also request submission of a site profile under the Contaminated Sites Regulation section 2(2). These site profiles are likely retained for information purposes by the local government. Only site profiles required under the provincial legislation are forwarded to the ministry for inclusion in the Site Registry and possibly for a decision by the director.

Sometimes. However, contamination migrating onto a residential property is a Schedule 2 activity for the residential property and can trigger the duty to submit a site profile. Other circumstances where a site profile is required for a residential property are the operation of an illegal drug lab or a commercial operation such as small engine or vehicle repair, paint shop, welding shop or other activity specified in the regulation.

For sites falling under Schedule 2 of the regulation that are undergoing an upgrade we would not require assessment of soil vapours on site to satisfy the requirements of the closure meeting. However, one of the release conditions is that the applicant commit to obtaining an Approval in Principle (AiP) for any offsite contamination. The preliminary site investigation, detailed site investigation, and remediation plan in support of the offsite AiP would have to include assessment of soil vapours if relevant to the type of activity onsite.

For more information regarding the release process and site upgrades, please refer to Administrative Guidance document 6.

Continued operation of the facility would have to comply with all WorkSafeBC regulations.

No, railway tracks do not fall within the definition of either G6 or G7 in Schedule 2. A rail line would only be a Schedule 2 activity where a "rail yard", maintenance facility or other freight handling occurred.

If the shafts were solely for the purposes of accessing the ore body or for ventilation, they would not be considered "coal mining". If the underground workings below your client's property were areas where coal extraction occurred, then that is a Schedule 2 activity and submission of a site profile would be triggered as per the Contaminated Sites Regulation. In spite of a Schedule 2 activity being identified, a ministry decision to require a site investigation generally does not occur unless there is some surface activity identified in sections IV to IX of the site profile.

No, a Contaminated Soil Relocation Agreement would not be required. The need for a CSRA is exempted by CSR section 41(3)(b).

Note that written permission is required if the receiving site is located within the Agricultural Land Reserve (regardless of our exemptions).

Yes, the contaminated soil may be treated on the source site without a CSRA (it must be clear that the source of contamination is migration from the source property and the impacted property is adjacent to the source property). Any soil stored and treated on the source property would have to comply with requirements of the Environmental Management Act and regulations. For the purpose of a CSRA the source and affected sites are considered one site.

If any soil with concentrations of substances exceeding CSR Schedule 7 standards is to be imported into the province a CSRA would be required. If the soil quality exceeds applicable land use standards for the site, a risk assessment may be required as part of the application. This would enable the ministry to determine if the risk-based standards of section 46 of the CSR would be met.

Yes, contaminated sediments are subject to CSRA requirements under section 55 of EMA as long as the soil is going to be deposited on land, rather than undergoing ocean disposal.

Yes, if contaminated soil is temporarily stored en route to an authorized facility, a CSRA is required unless the intermediate site is under federal jurisdiction (such as first nations reserve land) or is a site authorized to take waste. In support of the CSRA, the ministry would require details on the method of storage, length of storage and confirmation the soil has been transported to its final destination. Another CSRA would not be required when the soil is ultimately relocated to an authorized facility.

It may be necessary to assess soil pH at the source site if cadmium, copper, zinc and/or pentachlorophenol are potential contaminants of concern to determine whether the site is contaminated above land use standards for the receiving site. Also, pH measurements may be required to determine if the soil is hazardous waste and requires special management.

Under the Contaminated Sites Regulation golf courses are defined as having a commercial land use. As long as the soil to be relocated to a commercial property meets the commercial land use standards, no risk assessment will be required.

If a contaminant was present on site, it should be listed on the Certificate of Compliance, regardless of the source.

The site has a Schedule 2 activity - industrial woodwaste disposal. Although the woodwaste may not have been treated with pesticides you might detect non-chlorinated phenols in soil and/or groundwater which are listed in CSR Schedules 4 and 6. It may also be worthwhile to check for metals. A woodwaste landfill would be a contaminated site based on the presence of non-chlorinated phenols.

The definition (see Schedule 4 of the CSR) for LEPH and HEPH is for petroleum hydrocarbons so the intent of the parameter would be to not capture coal. Work at other coal impacted sites has shown PAHs and metals to be the predominant contaminants. Acid rock drainage has also been found in association with coal mining and processing. Petroleum hydrocarbons, if present, are generally associated with industrial operations surrounding coal production.

Yes. Assessment down gradient of the site for contamination originating from the service station is necessary.

The ministry's expectation is that contamination from a source site should be fully delineated. It needs to be confirmed that there is no contamination that has migrated from the source site. To sample groundwater only on the source site would demonstrate that the groundwater in the backfilled material is clean; that the cleanup at the source site has been successful; and that there is no ongoing source or recontamination. However, such a limited site investigation would not rule out any remaining down gradient offsite contamination.

Where groundwater contamination is significant and there is a reasonable possibility that groundwater could migrate along a preferential pathway to a receptor in less than 50 years (for aquatic life water use) or 100 years (for drinking water, irrigation or livestock watering uses), appropriate hydrogeochemical information should be obtained. However, where groundwater contamination is marginal (less than 10% in excess of the standards) and migration distances along preferential pathways are large (greater than 500 metres), a more qualitative assessment may be acceptable.

There are many possibilities that exist between these two requirements that would influence the extent of investigative effort. In addition to issues of significance of contamination and likelihood of transport there are issues of technical difficulty and risk of working around underground utilities. All of these have to be considered when making decisions about the type and extent of intrusive investigations to be conducted around preferential pathways.

As a result, we have not developed prescriptive guidelines for groundwater and preferential pathway investigations and we allow environmental professionals the ability to make decisions most appropriate for the conditions of their site. However, in making those decisions, the professional is responsible for defending them on the basis of factual information, lines of evidence and proper scientific analysis and interpretation.

It is not mandatory to install a well in sewer backfill, to measure water levels within the utility corridor or to conduct rigorous tests to determine hydraulic conductivity. However, professionals do need to know where utilities are located, where the point of discharge to surface is, and the utility invert and preferably backfill invert elevations. Also, environmental professionals should have a good idea if and how long (temporarily) the regional water table intersects the utility corridor and the approximate gradient of the submerged portion. The water level of the surrounding aquifer at a site can be predicted from wells nearest the utility and reasonable assumptions about the gradient between the site and the receptor (from utility plans and topographic maps). Professionals can do a grain size determination of the backfill or assume pea gravel or coarse sand and calculate a hydraulic conductivity value from empirical equations.

If the predicted pathway of the groundwater plume doesn't reach a receptor and does not move beyond the property line of the site and onto a neighbouring property, professionals should conduct sufficient investigations to verify that contamination has not migrated offsite.

Other supporting lines of evidence that might be presented in a preferential pathway assessment, particularly where a more qualitative approach has been taken, include the time frame over which the contamination has existed on site, whether the source has been removed, chemical characteristics of the contaminant that affect transport and any trends data showing a stable or shrinking groundwater plume. These supporting factors are not considered in Protocol 7 but would lend strength to conclusions where preferential pathways have been discounted.

As supplemental information, a definition of preferential flow pathways is also included in Protocol 13 (Screening Level Risk Assessment).

It depends on site-specific considerations. An approach that conforms to the intent of Protocol 7 would require calculation of the travel time through the aquifer to the pathway and then through the pathway to the receptor. On this basis, environmental professionals would have to consider both current and predicatively intersected preferential flow pathways. However, the effort one puts into the assessment again must be evaluated with respect to the significance of the problem and the likelihood of transport to and along the pathway. A similar approach to the response outlined in the previous question would be reasonable.

Fire halls are instutional and often contain living quarters so residential land use is appropriate for these sites.

The situation you describe is one where the resin material removed from the site had visual properties which made its removal an easy process. While the resin's composition is known from the manufacturer's information, the specific constituent substances were never detected in confirmatory samples from the site. In the current situation, for completeness, remediation undertaken was confirmed using phenol and formaldehyde. Therefore, it would be preferable to list phenol and formaldehyde as contaminants of concern.

Where there is contamination at the boundary of a site and engineered works need to be put in place in order to prevent recontamination these works should be stamped by an engineer certified to practice in British Columbia. The engineer signing off on the engineered works need not be an Approved Professional.

If metal or other contamination is shown not to be mobile and there is no significant risk of migration of these contaminants from the source site, there is no need to install engineered works to prevent contamination of neighbouring sites.

Under the Oil and Gas Waste Regulation, the Oil and Gas Commission may issue effluent permits associated with operations and remediation in the oil and gas sector.

Peat farming or mining would be considered an industrial activity. Therefore, Contaminated Sites Regulation standards for industrial land use would apply. However, if the land is to revert to a natural state or be used for some other activity following decommissioning of the extraction operations industrial land use may no longer apply.

From the contaminated sites legal perspective, there would be nothing preventing an applicant from obtaining a landfill permit or operational certificate. However, it would be prudent to thoroughly characterize soil and groundwater prior to constructing the facility. When the facility is to be decommissioned it might be necessary to show that contaminants not associated with operation of the facility are due to background concentrations.

To establish whether drinking water standards apply, the following process should be followed:

• Check existing water well records and with the local municipal government to determine if wells exist in the area. Existing water well records can be searched for on-line using the BC Water Resources Atlas (http://www.env.gov.bc.ca/wsd/data_searches/wrbc/index.html).
• Where water wells exist, confirm with the property owner that the wells are not used for drinking water and are not reasonably anticipated to be used for drinking water in the future.
• Obtain confirmation from the local government that the area in question is supplied by municipal water and that groundwater is no reasonably anticipated to be used for drinking water in the future.

In general, at the preliminary site investigation stage of investigation, if the receptor is greater than 1.0 [1.5] kilometre for AW and DW respectively from the site boundary depending on the receptor water use, then the distance is considered to be generally consistent with a travel time greater than 50 [100] years AW and DW respectively, for most sites. However, if for some reason the site conditions would suggest a travel time of less than 50 [100] years, then additional work should be considered or, professional judgement should be applied to ensure that the 50 [100] year travel time factor has been met.

At the detailed site investigation stage of investigation, it is the travel time estimate that should be used as the basis for determining the applicable water use standards, not the distance. Consequently, the water use must be re-established at the detailed site investigation level using a travel time calculation as the basis for this determination.

Wide area sites are complicated scenarios, each with a unique set of circusmtances. As such, general guidance is not applicable. Please contact the ministry case file worker for the site for advice.

They may be applied but do not have to be applied. The definitions for a number of agriculturally-related uses for soil and water relate to food production and consumption. This is apparent when one reviews the definitions for agricultural soil use, irrigation use, and livestock watering water use. If a proponent for a sports field or golf course wished to be reassured that the water applied in their irrigation system was protective for the grass at their site then they may wish to apply the water standards for the irrigation use as these are deemed protective.

There may also be drinking water uses or aquatic life uses that would apply.

Under section 12 of the Contaminated Sites Regulation, the Director may specify land, water and sediment uses at a site (see sections 12 (3), (4), (4.1). Note that this is a discretionary power of the Director. Also, please see section 12 (5) which lists the factors that the Director must consider when exercising the above discretionary power.

In the case of Approved Professional submissions, it would be unusual for the Director to exercise directly this power under section 12 since Approved Professionals are qualified to make such assessments.

Further, should your client wish to seek the Director's approval for a "no water use" designation, your client should anticipate being required to submit a contaminated sites service application together with a report describing all relevant information required under section 12 (5) prior to the Director making such a ruling. Note that the Director may elect not to exercise his or her discretionary authority under section 12 of the Contaminated Sites Regulation.

The ministry does not recognize travel time estimates in the vertical direction. At this time, the groundwater travel time calculation to determine applicable groundwater use is based on horizontal flow. This means that a groundwater drinking water use would apply at a site where a drinking water wells exists within 1.5 km or 100 years horizontal travel time from the site. This is a conservative approach where the contaminated groundwater is shallow and there are confining layers of substantial thickness above the drinking water aquifer. However, it is necessary to have simple clear rules for the application of regulatory standards and generally these rules tend towards conservatism. The horizontal flow assumption of the travel time calculation was made because:

• the thickness, conductivity and continuity of underlying confining layers are often not investigated at sites;
• the conditions and continuity of confining layers between a site and the drinking water well(s) are typically not known;
• the extraction rate, zone of influence and construction details of the drinking water well(s) are typically not known;
• the integrity of the drinking water well, i.e. potential cross-connection between deep and shallow aquifer, are not known; and
• the potential complexity, time and cost introduced in the investigation and the audit of investigations considering the above information.

In some sections of Surrey the following interpretation has been applied - thick regionally significant confining units - the ministry has permitted, where these conditions have been satisfactorily demonstrated, that the groundwater use of the shallow aquifer be determined on the basis of receptors of the shallow groundwater alone. In such a situation, different groundwater uses for the shallow and deep aquifers have been permitted. To provide adequate protection of the deep aquifer and avoid the need to make complex assessments of confining units, the groundwater use determined for the deep aquifer and by default the Schedule 5 soil standard to protect this groundwater use is applied to the lower 5 m of the overlying confining unit.

The remediation standards for NAPL are not explicitly defined in the CSR. The Director's current advice on application of the default generic numerical soil and water standard for "non-aqueous phase liquids not present" may be found in Protocol 13, Screening Level Risk Assessment.

The following interim procedure sets out the purpose, rationale, rules of application, administrative process and decision basis by which groundwater standards that apply to a deep confined aquifer at a site may be deemed not to apply to an overlying unconfined aquifer. These rules derive from Section 12(4) and 12(5) of the CSR that grants discretionary authority to the Director to determine groundwater use. They expand upon and further clarify existing guidance around use determinations and applicable standards provided in Technical Guidance 6. The strict interpretation of the travel time rules of Technical Guidance 6 is that travel time is calculated on the basis of horizontal advective flow in the aquifer of interest from the location of the plume front to the location of the nearest groundwater receptor. Definition of "groundwater travel time" and "plume front" can be found in Protocol 7.

Purpose:

This interim procedure allows groundwater uses and applicable standards (and dependent matrix soil standards) for shallow unconfined aquifers to be determined on the basis of shallow groundwater uses alone and independent of groundwater uses that may apply to an underlying confined aquifer in circumstances where thick natural confining units separate the two. Groundwater use determinations made under this procedure will be on the basis of a formal submission to the ministry. A determination so made can be used by an Approved Professional for purposes of completing regulatory reviews authorized under Protocol 6. This interim procedure applies until such time as guidance for vertical travel time assessment is developed.

Rationale:

Continuous natural confining units comprised of thick alluvial silts and clays can significantly impede groundwater flow in the vertical direction and in some circumstances act as near-impermeable barriers to vertical flow. Present CSR guidance assigns the most sensitive groundwater use determined for all aquifers underlying a contaminated site to the entire hydrogeologic profile. In simple terms this means that a drinking water use determined for a deep groundwater aquifer at a particular site would render all groundwater underlying the site subject to the CSR drinking water standards and all soils subject to CSR soil standards protective of this groundwater use. This interim procedure establishes simple conservative rules to allow consideration of the significant reduction in groundwater flow velocities and travel times where thick natural confining units separate shallow contaminated soil horizons from deep confined aquifers.

Rules of Application:

• the groundwater use (and Schedule 6 standards) that applies to the confined aquifer also applies to the lower 5 m of the overlying aquitard/aquiclude and likewise the Schedule 5 soil standards protective of this use;
• the groundwater standard (and soil standard) determined for the shallow unconfined aquifer will be based on groundwater uses of that aquifer alone.

• Required hydrogeological conditions (decision basis):
  • the semi-confining unit must be a continuous mapable unit identifiable on a regional scale (much greater that a square kilometre) and continuous across the site and between the site and nearest receptor of groundwater in the confined aquifer;
  • the semi-confining unit must be mapped as mainly silt to clay in composition with a maximum K of 1 x 10-7 m/s and must be reasonably determined to be absent of sand interbeds, unfractured, and continuous across the extent and future migration trajectory of the shallow subsurface contamination;
  • the unit must be mapped at 5 metres minimum in thickness across the site and reasonably determined to extend at this thickness between the site and nearest receptor of groundwater in the confined aquifer;
  • the above must be confirmed at the site of interest on the basis of detailed hydrogeological investigations and offsite on the basis of a search of available geological records, maps and reports (as might be available in Geological Survey of Canada (GSC), provincial, municipal or other regional reports) as reasonably augmented by field investigations;
  • contamination must be contained within the shallow aquifer, must be determined not to have penetrated to the deeper aquifer or within the lower 5 m of the natural confining unit and these conditions must be anticipated to persist;
  • dense nonaqueous phase liquids (DNAPLs) have not contaminated the subsurface.

Process:

• determinations of applicable water uses under this interim procedure will be made on the basis of a formal written application to the ministry and supporting technical information. The application should be submitted to the Client Information Officer;
• supporting technical information to include a hydrogeological report prepared by a qualified hydrogeologist on the basis of detailed hydrogeological investigations and qualified hydrogeologist's statement that required hydrogeological conditions are satisfied;
• Ministry reviews completed under this procedure will be subject to hourly review fees in accordance with the CSR.

Currently we lack a protocol to establish site-specific standards for water so it is not possible at this time to develop SSS for groundwater under the CSR.

Ministry pre-approval of the background groundwater estimates under Protocol 9 is required.

The remediation standards of the ditch will depend on whether the ditch is considered aquatic or terrestrial habitat. If a ditch is regularly maintained by a private party, a local government or provincial ministry and is dredged or bottom scoured on a regular basis, the ditch would likely be considered terrestrial habitat and applicable soil standards would apply. If the ditch is considered aquatic habitat, sediment standards would apply. If the local government is not able to advise you on the appropriate habitat classification, a professional biologist should be consulted to characterize the habitat of the ditch.

The ground underlying the stream would be considered sediment while the riparian strip is considered to be wildlands. The width of the riparian strip is often specified in local government bylaws. In the absence of local government direction on riparian strip width, please refer to the Riparian Areas Regulation.

In order to get ministry signoff for a Certificate of Compliance, these exceedances would need to be addressed. This could be/may be done by:

• Ruling out the application of the drinking water standards for groundwater based on flow direction and/or travel time.
• Assessing background levels of substances and getting a release under Protocol 9, "Determining Background Groundwater Quality".
• Low flow sampling which may identify lower concentrations.
• If reducing conditions resulting from the presence of residual hydrocarbons from the former gas station result in the metal exceedances and it is not known how long it will take until metal concentrations will decrease, then the remaining route is to undertake a risk assessment.

No, it has not. The use of the 10x multiplier was dictated as a matter of ministry policy to reconcile CSR regulatory consistency with long-standing considerations of dilution capacity when authorizing discharge permits under the former Waste Management Act, and other existing regulations (e.g. Antisapstain Regulation). At the time the CSR was under development, many permits assumed an availability of 20:1 dilution. The Contaminated Sites Standards Taskgroup (CSST) considered three options related to typical dilution capacity in B.C. receiving waters:

1. Assume no dilution is available (i.e., set CSR aquatic life standards equal to ambient aquatic life water quality guidelines);
2. Assume standard 20:1 dilution was routinely available (i.e., set CSR aquatic life standards equal to 20x ambient aquatic life water quality guidelines); and
3. Assume standard 10:1 dilution was routinely available (i.e., set CSR aquatic life standards equal to 10x ambient aquatic life water quality guidelines).

In the end the ministry adopted the compromise 10:1 assumption (see attached excerpt re: Regulatory Consistency from Contaminated Sites Standards Review Workshop. March 20-22, 1996. BC Environment Responses to Expert Panel Recommendations - available at: http://www.env.gov.bc.ca/epd/remediation/standards_criteria/standards/bc_en_res_to_expert.htm

This, along with a similar error in allowable cadmium concentrations, will be corrected in the omnibus updating of the CSR standards planned for 2010/11. In the meantime, please use the following when determining applicable aquatic life standards:

The short answer is that neither ammonia (NH₃) nor ammonium (NH₄+) are prescribed substances in soil under the Contaminated Sites Regulation. Consequently they are not regulated in soil for CSR purposes and you have no duty to characterize the soil of your site for these two substances.

Ammonia salts can be found as a normal constitutent of virtually all soils as a consequence of natural nitrogen fixation.

Ammonia is a prescribed substance in water (see CSR Schedule 6). Furthermore the herbicide ammonium sulfamate is also a prescribed substance in soil (see CSR schedule 10).

Typically, a site is only characterized for a substance for which there is historical evidence of commercial/industrial use at the site, or for which a spill or other source of contamination by the substance is suspected or can be reasonably inferred.

Historically, the Land Remediation Section has accepted statistical approaches to characterizing concentrations in single wells where concentrations fluctuate temporally or trends are downward. We have also accepted a statistical argument for characterizing zinc concentrations in single wells where both the pH and zinc concentrations fluctuated temporally. We have also accepted localized exceedances that are within 10% of the CSR standard.

The Section has not accepted statistical representations of spatial groundwater data for purposes of site characterization except for approvals under Protocol 9, “Determining Background Groundwater Quality”. We have used this approach in some circumstances for sites under remediation. Because groundwater investigations are so limited and methods so imprecise relative to the temporal and spatial variability that exists, there are rarely circumstances where adequate data is available to conduct valid statistical analysis except for single wells. However, we are reviewing how statistical approaches might be considered in future technical guidance.

Based on the limited data provided, it is recommended that the applicant proceed with a background groundwater quality determination application.

The CSR irrigation water standards for molybdenum ensure that molybdenum present in irrigation water used at a site will not result in molybdenum enrichment in the soil to such an extent that forage crops grown on the site will bioconcentrate molybdenum to a level which would induce molybdenosis in herbivores (i.e. cattle).

Depending on the forage conditions at your site, apply the following:

See: http://www.em.gov.bc.ca/Mining/Geolsurv/Terrain&Soils/frbcguid.htm

Unlike Technical Guidance 9, “Chlorophenol Aquatic Life Water Quality Standards” there is no compiled Land Remediation Section guidance for ammonia, hence the footnote to consult the Director for further advice.

The aquatic life water (AW) standards of CSR Schedule 6 are based on the B.C. Approved Water Quality Guidelines for Nitrogen – nitrate, nitrite, ammonia circa 1986 (freshwater AW) and 1990 (marine AW). These guidelines were updated in 2001; however, the changes (to marine guidelines) have not yet been used to revise the Schedule 6 standards. That is expected as part of an omnibus updating to the CSR environmental quality standards planned for 2011/12.

Freshwater

The freshwater CSR Schedule 6 aquatic life standards are based on “Table 4. Average 30-day Concentration of Total Ammonia Nitrogen for Protection of Aquatic Life” from the approved guidelines see http://www.env.gov.bc.ca/wat/wq/BCguidelines/nitrogen/nitrogen.html#tab4. That table provides pH (6.5 – 9.0) and temperature (0° C – 20° C) dependent freshwater guidelines for ammonia.

Marine

The marine CSR Schedule 6 aquatic life standards are based on “Table 2. Average 5 to 30 day Concentration of total Ammonia Nitrogen for Protection of Saltwater Aquatic Life” from the ministry’s approved water quality guidelines — see http://www.env.gov.bc.ca/wat/wq/BCguidelines/ammonia.html#tab2. Note that the marine water quality guidelines were changed between 1990 and 2001 so the Schedule 6 standards in some cases differ from the Table 2 water quality guidelines). Table 2 provides pH (7 – 9), temperature (0° C – 25° C) and salinity (10 -30 g/kg) dependent marine water quality guidelines for ammonia.

The director would use these two tables to derive: pH and temperature specific freshwater, and pH, temperature and salinity, specific CSR freshwater and marine water quality standards if asked to provide further advice.

The CSR Schedule 6 livestock watering water quality standard for fluoride is based on the B.C. Approved Water Quality Guidelines for fluoride.

The Schedule 6 standard is specific to:

• wildlife,
• dairy cows,
• breeding stock (e.g. laying hens, sows, etc.), and
• any livestock raised on high fluroide feed or mineral or bone meal supplements.

The standard does not incorporate a wide margin of toxicological safety and should be viewed as a general, worst-case maximum to protect all livestock.

For short-lived, non-reproductive livestock (i.e., livestock other than those listed above), the director might raise the standard to a maximum of 2000 µg/L.

However, that level would severely limit the type of livestock associated with a CSR agricultural land use and would likely require specific livestock type restrictions on any Certificate of Compliance issued.

The arsenic livestock ingesting soil and fodder standard was derived in 2000. At that time, no suitable herbivore TRV was available for arsenic. Consequently, a surrogate TRV was derived using a carnivore (beagle dog) in accordance with the Contaminated Soils Standards Taskgroup protocol. So, it is not surprising that you can’t find a TRV for arsenic in the literature.

Terms

TRV: Toxicity Reference Value (mg/kg/d - calculated value)
BW: Body Weight (kg - derivation assumes young pig BW = 30 kg)
IRfood: Ingestion Rate Food (kg/d - derivation assumes young pig IRfood = 2.93 kg/d)
Bv Soil: Soil to plant transfer coefficient (unitless - derivation assumes Bv = 0.0371, Bechtel and Jacobs, 1998)

MATC: Maximum Tolerable Concentration (mg/kg/d – calculated value)
UF: Uncertainty factor cross species extrapolation (unitless - derivation assumes UF = 3 extrapolation from dog LOAEL to pig)

LOAEL: Lowest Observed Adverse Effect Level (mg/kg/d – derivation used LOAEL of 2.2 mg/kg/d for beagle dog)
NOAEL: No Observed Adverse Effect Level (mg/kg/d - calculated value)

ACR: Acute to Chronic Ratio (unitless - derivation assumes ACR of 5.6)

Derivation

(Soil standard) Csoil (mg/kg) =

Where:
TRV =
MATC =
NOAEL =

The math works out to 24.5575 mg/kg. For the Schedule 5 matrix this was rounded up to 25 µg/g.

SLRA is a screening tool that may be utilized on a voluntary basis at contaminated sites. It provides screening mechanisms primarily for contaminants in the soil, vapour, and groundwater media where, subject to precluding conditions, it is deemed that the contaminants in the respective media pose an acceptable risk to human and ecological health. SLRA may be used in support of an instrument application to the ministry and may also be used in tandem with remediation and/or Detailed Risk Assessment activities. For further information, please consult Protocol 13, the ministry responses on the comments to the earlier draft of Protocol 13 and Q/A responses in these FAQs.

SLRA and Detailed Risk Assessment (DRA) are both risk-based approaches to site remediation. The approaches are independent of one another and vary in scope and complexity where SLRA is a constrained screening type risk assessment while DRA is an unconstrained comprehensive risk assessment. In terms of application, SLRA may be applied independent of, or in coordination with, DRA. However, where both SLRA and DRA are applied at a site, pathways screened using SLRA should be re-evaluated in the problem formulation stage of the DRA to confirm that the assumptions and conditions inherent in SLRA are satisfied at the site.

Use of risk management measures is permitted in SLRA (e.g., placement of permanent barriers, cover material, groundwater control measures, etc.). Such measures could be utilized to render an exposure pathway as inoperable. Where a risk management approach is undertaken, prescription of monitoring, maintenance and reporting measures is required. Such measures must be specified in the SLRA report and referenced in the existing conditions in the approval in principle and certificate templates submitted as part of risk-based instrument applications to the ministry. This is to ensure that risk management measures undertaken to render a pathway as inoperable remain in effect into the future. Note that where the design and/or implementation of a particular risk management measure falls within the field of practice of a registered professional (e.g., P.Eng., P.Geo., P.Ag. or RPBio), sign-off by the respective registered professional of the risk management measure implemented (in support of a Certificate of Compliance application), or to be implemented (in support of an Approval in Principle application) must be included in the SLRA report.

The 1 m depth scenario (for soil contamination located greater than 1 m of ground surface) includes the requirement that contamination will not migrate vertically upwards into the 1 m interval of soil (e.g., by capillary transport or diffusion). To account for any such potential vertical migration, an appropriate additional depth separation or use of a capillary break must be utilized. The vertical migration aspect is to be included in a subsequent version of Protocol 13.

The intent of section 3.2 is to only preclude assessment of the listed substances or conditions in SLRA and not limit application of SLRA in its entirety. It is acknowledged that the text is unclear and will be revised in a subsequent version of Protocol 13. As an example, for the case where groundwater contamination has migrated off-site and exceeds the CSR drinking water use standards (at sites where drinking water use applies), in effect, application of only the human health exposure pathway (HW) would be precluded at the site. All other exposure pathways could still be assessed using SLRA.

Ionizing organic substances are not included in SLRA at present due to the complexity associated with the pH and temperature dependency of the Koc parameter for the substances. However, ionizing organic substances are intended to be included in subsequent version of Protocol 13.

The deep-rooting plants or trees precluding condition applies to any palnts or trees at the present time. This issue remains under review and is subject to revision in subsequent versions of Protocol 13.

Reclamation with shallow rooting species would technically result in the precluding condition not applying at the site. However, as noted, this type of reclamation measure is essentially a mitigative measure and therefore would need to be monitored and maintained into the future to ensure that the system remains shallow rooting.

An appropriately designed liner system would be considered an example of a satisfactory permanent barrier.

The vapour exposure pathway may only be assessed at sites where wildlands land use applies, i.e., at present, there is no screening mechanism available for the human health vapour exposure pathway in SLRA for non-wildlands land use sites.

Following the introduction of vapour standards in the Stage 6 amendments to the Contaminated Sites Regulation, the pathway is assessed by: 1) comparison of site vapour concentrations to the vapour standards in CSR Schedule 11 (HV-1); and 2) comparison of calculated vapour exposures relative to the prescribed scenario exposure durations (HV-2).

The environmental health terrestrial soil exposure pathway would pass for this case as the pathway would be exited at TS-2 (contamination is not within, or may migrate to within, 1 m of ground surface). Application of SLRA at upstream oil and gas sites is not precluded.

A "No" response for HW-3 can only be provided by applying Appendix A as per Note 9 of the SLRA questionnaire. This involves predicting the concentration of manganese at the property boundary using the leaching and groundwater transport assessment tools in Appendix A. This is a future prediction of plume extent as opposed to the current state of the plume. If the predicted concentration at the property boundary exceeds the CSR DW standards, then the water exposure pathway fails. The plume should then be addressed by further remediation and/or Detailed Risk Assessment.

As the substance concentration does not exceed a soil standard (or have a soil standard as the subject substance), it is difficult to determine what soil should be tested for leachate assessment. Accordingly, only application of the groundwater transport assessment in Appendix A is necessasry for the substance exceedance in groundwater in such cases.

The determination of what water uses apply at a site is done in accordance with Technical Guidance Document 6. In TGD6, aquatic life water use is determined on the basis of the site boundary unless the plume has migrated off-site in which case the reference point is the leading edge of the plume. For this case, CSR AW standards would be deemed to apply based on the proximity of the site to the river. However, in evaluation of the environmental health aquatic life water exposure pathway in SLRA, at question AW-3 in the SLRA questionnaire, the transport assessment is based on the leading edge of the plume. Therefore, although aquatic life water use may apply to the site, you may be able to screen out the aquatic life exposure pathway using the screening transport assessment in SLRA.

The reference to theoretical solubility in the transport assessment was removed in the current version of Protocol 13 as the presence of nonaqueous phase liquids are a precluding condition in SLRA. For organic substances in SLRA, transport assessment (Appendix A) is conducted using the highest concentrations from leachate assessment (Steps 1 and 2) or actual groundwater concentrations. Where groundwater concentrations are considered biased by entrained sediment or other causes, refined groundwater sampling measures are recommended to remove the respective biases. Where this is not possible, groundwater concentrations exceeding theoretical solubilities should be used as a conservative measure.

It is acknowledged that this is not clear in the current questionnaire and will be clarified in a subsequent version of Protocol 13. On an interim basis, for sites where application of an exposure pathway is not possible because of a precluding condition, it is considered satisfactory to mark in "n/a" as the Yes/No response to the respective questions in the SLRA questionnaire and to specify the respective precluding conditions in the SLRA report. For example, for a site where it’s not possible to apply the human health vapour exposure pathway because wildlands land use does not apply, an “n/a” response should be provided for question HV-1 in the SLRA questionnaire and soil vapours should be identified as a precluding condition in the SLRA report.

Signature by the registered professional biologist should be included in the signatory section of the completed SLRA report. This signatory requirement is to be included in a subsequent version of Protocol 13.

The TCLP test was selected for the soil pH range of 5 to 5.5 to be conservatively representative of leachate that may be developed in acidic soils based on the recommendation in the Science Advisory Board SLRA report. Although the test is intended to simulate biological degradation in municipal solid waste landfills, it is noted that both organic and inorganic contaminants may be leached in such environments and thus TCLP analysis is intended to be a conservative test in this regard.

Before January 1, 2010

If you do not have soil, sediment (if applicable), and water data for a particular vapour PCOC, then you cannot complete this vapour PCOC refinement step for that substance – i.e., you will have to retain that substance as a vapour PCOC for your site. Furthermore, since you do not have soil, sediment, and water concentration data for the substance, you will need to collect vapour data to investigate potential vapour contamination by that substance – i.e., you will not be able to model the concentration of that substance in vapour using soil, sediment, or water concentration data.

Yes. Note that neither the parent laboratory nor the mobile laboratory actually has to be CAEAL (now the Canadian Association for Laboratory Accreditation, or CALA) certified for the particular analyte of concern. The Environmental Data Quality Regulation allows the Director to request that environmental samples be analyzed for “designated characteristics” at a CALA registered laboratory. Designated characteristics means characteristics, analytes, or parameters designated for inclusion in a CALA inter-laboratory quality assurance / quality control (QA/QC) comparison program. Typically, the Director would only request analyses for designated characteristics where the results would constitute legal samples for use in legal proceedings under the Environmental Management Act in a court of law. For most regulatory purposes (e.g., assessment/ confirmatory samples under the CSR), the Director simply requires that the laboratory be CALA certified for one or more of the analytes or services that the lab offers. Basically, CALA certification shows that the lab is cognizant of proper QA/QC procedures and is participating in at least one formal CALA inter-laboratory QA/QC comparative program.

No. If you do not detect VPHs or VPHw in soil or water at your APEC, then you do not need to retain VPHv as a vapour PCOC for that APEC (i.e., you do not have to analyze vapour for VPHv), even if you do detect LEPHs or LEPHw.

Note that this question arises because VPHv includes the C6-13 carbon range, while VPHs/w includes the C6-10 carbon range and LEPHs/w includes the C10-19 carbon range. So, screening out VPHv as a vapour PCOC where LEPHs/w is detected in soil/water equates to ignoring the potential vapour risks associated with the C10-13 range of LEPHs/w. Based on information currently available to the ministry, the C10-13 fraction of VPHv is generally a minor contributor to the overall toxicity of VPHv. As a result, the ministry considers the potential vapour risks associated with the C10-13 fraction of LEPHs/w to be quite small, and thus the elimination of VPHv as a vapour PCOC where VPHs and VPHw are not detectable in soil or water is considered to be defensible.

Note also that elimination of VPHv as a vapour PCOC where VPHs/w is not detectable but LEPHs/w is detectable is optional – for completeness, one may want to retain VPHv as a vapour PCOC under these conditions.

Yes, as long as you have thoroughly investigated the soil, sediment, and water at this APEC. Note that the detection of benzene in vapour at your APEC may indicate inadequate soil, sediment, or water characterization; the presence of an adjacent or overlapping APEC; or sampling or laboratory error. All of these possibilities should be thoroughly investigated and discussed in the site investigation report(s) if you choose to eliminate benzene as a vapour PCOC for the APEC in question.

One vapour sampling event is considered sufficient for characterizing vapour contamination when the applicant makes a convincing scientific argument (citing literature, modeling results, etc.) that additional sampling events are not needed to confidently predict the worst-case (i.e., highest) substance concentration expected in the breathing zone of the site over the period of time the desired contaminated sites legal instrument is to remain valid.

This policy exists for vapour characterization because substances with a liquid specific gravity greater than one have the potential to form dense nonaqueous phase liquids (DNAPL). DNAPL in soil is difficult to characterize, so vapour arising from DNAPL in soil will also be difficult to characterize through modeling alone. Note that this policy only applies to vapour characterization – the use of modeling to estimate substance concentrations in vapour from substance concentrations in soil for substances with a liquid specific gravity equal to or greater than one is permissible in risk assessment as long as it is supported by defensible scientific rationale.

Generally speaking, vapour contamination (along with soil, sediment, and water contamination) must be fully delineated before an Approval in Principle will be issued.

Yes, but note that given the scarcity of guidance on such sampling, collection and use of vapour data from groundwater monitoring wells raises many questions to which the ministry currently does not have answers. For instance, how does one collect a representative vapour sample from an apparatus that is designed specifically for groundwater monitoring? What are the potential sources of sampling error? Should vapour attenuation factors be applied to such data? If so, should they be based on the distance from the base of a building to the top of the capillary fringe, the top of the vapour sampling screen, the bottom of the bentonite seal, or some other reference point? Furthermore, is such vapour sampling appropriate for sites with potential vapour sources in soil?

Given these issues, the ministry strongly recommends that when you use vapour data collected from groundwater monitoring wells to characterize vapour contamination at your site, you (a) provide a detailed description and diagram of your sampling apparatus and how it works, (b) thoroughly discuss the representativeness of the vapour data, (c) thoroughly discuss the rationale for all professional judgement decisions (e.g., explain why a particular vapour attenuation factor was chosen), and (d) thoroughly discuss all your assumptions and uncertainties.

Yes.

No. As for other environmental media (i.e., soil, sediment, and water), you must first identify and fully delineate vapour contamination onsite and offsite, and then remediate the vapour contamination via source removal, risk assessment, or risk management.

The Approved Professional soil vapour advice and practical guidelines development panel provided the ministry with the following draft recommendation regarding leak testing, which the ministry endorses:

"It is recommended that leak testing be completed at least once for every soil vapour sampling installation (whether the installation is temporary or permanent). If additional sampling events are to be conducted at permanent installations that were previously tested, leak testing should be completed at approximately 10% of the installations during each subsequent sampling event.”

The Approved Professional soil vapour advice and practical guidelines development panel provided the ministry with the following draft recommendation regarding duplicate sampling, which the ministry endorses:

“...at least one field duplicate should be collected per sampling event, or one per ten samples, whichever is greater. Field duplicates should be collected using a “T” splitter, as opposed to collecting the two samples sequentially."

The risk assessment needs to address all human and ecological exposure pathways –— the risk assessor must demonstrate and confirm that all site PCOCs meet risk-based standards for all human and ecological exposure pathways. This policy exists because (a) the CSR numerical standards do not address all exposure pathways, and (b) assumptions used to derive the numerical standards may not apply at your site. Note that a statement from the risk assessor that the assumptions inherent in the numerical standards apply for a given exposure pathway should suffice to address the risks for most, if not all, exposure pathways at the site other than the human-vapour pathway.

No. You are required to verify that the vapour management system works (i.e., that substance concentrations in breathing zone vapour meet CSR numerical or risk-based standards), but this does not mean that you must conduct post-implementation indoor vapour sampling as this may not be feasible for some substances or some sites. Other system verification approaches, such as a combination of leak tracer testing, vapour modeling, literature citation, and qualitative discussion are acceptable to the ministry as long as they are supported by defensible, documented scientific rationale.

Yes. Either approach is acceptable as long as you verify that substance concentrations in breathing zone vapour will meet CSR numerical or risk-based standards at the time of occupancy and will continue to meet these standards over the period of time the Certificate of Compliance is to remain valid.