Highly developed environmental regulation systems in both countries have established clear guidance on managing soil pollution. In addition to national level regulatory structures, provinces, territories and states are allowed to enact regulatory guidelines more stringent than the national minimums. These layers of legislation contain risk-based numerical criteria for assessing sites, taking into account the nature and behaviour of contaminants in the environment and exposure pathways. In addition to soil pollution regulation promulgated by national and sub-national environmental regulatory agencies, separate agricultural and public health agencies generate complementary soil pollution regulations. Regulation development is informed by academic and government scientist generated data. In the United States of America it is often individual states which will take the lead on instigating new environmental regulations based on local impacts (e.g. PFAS in Minnesota due to large PFAS production in state) or public sentiment (e.g. California’s political willingness to adopt more stringent regulations) with federal agencies joining in to promulgate national level regulations. Cooperation between national and subnational agencies is typically very high.
Despite this high level of regulatory development, the US EPA openly states that their Report on the Environment (ROE) polluted land indicators are limited in two important ways:
These two limitations are equally applicable to Canadian land evaluation.
To address the need for additional soil-specific national level coordination the United States of America established a soil science interagency working group and produced a “Framework for a Federal Strategic Plan for Soil Science” to guide future efforts (National Science and Technology Council, 2016).
The CCME is working to address a range of issues associated with the completion of provincial/territorial and federal environmental assessments (EA) in Canada, including process inefficiencies, overlapping mandates and responsibilities, lack of timeliness, and differing criteria triggering EAs (CCME, 2014).
The production and release of new potential soil contaminants into the environment is a challenge in this region as it is worldwide. In the United States of America, new chemicals are not required to be proven non-hazardous before use and release into the environment which leads to environmental regulation always needing to catch up with contaminants and polluted sites. Canada has the New Substances Notification program under the Chemicals Management Plan to examine the potential risks to Canadians and their environment before the substances enter the Canadian marketplace (CCME, 2014; Health Canada, 2012).
Given the size and diversity of the national economies coupled with robust environmental monitoring programs, this region is often among the first to identify and begin to address new soil pollution problems as they arise. Unfortunately, information needs greatly outstrip the available resources and compete with the need to implement remedial actions (Health Canada, 2017a).
New research needs have been identified in the areas of interaction, fate and toxicity of micro plastics and plastics’ additives, pharmaceutical and personal care products, persistent organic chemicals (such as PFAS), and mercury, as well as their degradation products in soils (RWS Leefomgeving and OVAM, 2016; USGS, 2017b). All of these are pressing environmental topics deserving of far more investigation than funding allows.
Research funding for PFAS has been increasing in recent years as realization of the geographic scope of pollution and potential health problems has become more widespread. Currently about 3 000 fluorinated compounds have been produced and are used in many industrial and consumer applications. Out of these 3 000 compounds produced, longer chain PFAS, such as PFOA and PFOS, were identified as mobile, persistent and non-degradable in the environment (Mueller and Yingling, 2017). The US EPA has multiple programs addressing the PFAS (US EPA, 2019r). Both the United States of America and Canada have restricted the manufacture and usage of certain PFAS compounds, industry shifts to alternate non-regulated fluorinated compounds stymies soil clean up and regulations (Dean et al., 2020; OECD, 2020). Although at the national level the United States of America has not yet taken regulatory actions some states have moved forward on their own (Dintzer and Namuo, 2019). Canada is moving forward with further restrictions on PFAS compounds (Government of Canada Public Works and Government Services Canada, 2018).