Midterm

Question 1

What is the difference between reclamation and remediation?

Answer 1

Reclamation: Stabalization, reconstruction, maintenence, recontouring, re-vegetation of the surface or subsurface.
Remediation: Removal or neutralization of all chemical substances from surface or subsurface.

Question 2

List 4 things that should be known for a site

Answer 2

Size, where spills/ incidents occurred, before and after aerial images, waterways, geological formations, site history, future land use, drilling waste disposal, any known contaminants.

Question 3

What happens if there is no evidence, not enough evidence or evidence of contamination?

Answer 3

move on
Intrusive sampling
Intrusive sampling

Question 4

What are 5 different kinds of sites in Alberta?

Answer 4

Oil well, gas plant, power plants, waste water, gasoline retail, dry cleaners, mine sites, snow storage, natural, residential, commercial, agricultural, industrial

Question 5

What are benefits of conducting Environmental Site Assessments?

Answer 5

Legal liability, knowledge of contaminants, public image improvement

Question 6

What are the 5 levels of Environmental Site Assessments?

Answer 6

Phase I, Phase II, Phase III, Phase IV, Phase V

Question 7

What is the purpose of a Phase I?

Answer 7

Collect existing information, evaluate current and historical land use, estimate likelihood that contaminants exist

Question 8

Is a Phase I always its own report?

Answer 8

No. It is always done but not always its own report.

Question 9

What is a Phase II and when is it used?

Answer 9

Intrusive sampling to determine types, levels, location, depth and range of contaminants. It is used when a Phase I indicates further assessment is required or not enough information is available.

Question 10

What is a Phase III?

Answer 10

The solution phase of an ESA. This develops a remediation plan.

Question 11

What is a Phase IV?

Answer 11

Regulatory closure. A regulator must agree that a site can be returned to its former and future land use. (Reclamation certificate)

Question 12

What is a Phase V?

Answer 12

Follow up and ongoing monitoring

Question 13

What is the purpose of records review

Answer 13

Collect available information on past activities that may have lead to site contamination. Neighboring sites must be considered.

Question 14

What information should be included in a Phase I ESA

Answer 14

Prior site assessments, regulatory info, land titles, site visit info.

Question 15

What is the purpose of a site visit?

Answer 15

Site observations, evidence of contamination, document all equipment, buildings, wells, storage, pits, lagoons, standing water, waste water, stains, odours, stressed vegetation.

Question 16

Who should be interviewed and why for an ESA

Answer 16

Landowners, employees, operators, neighbors, residents, occupants. To corroborate info gathered in the previous activities.

Question 17

What are the 4 parts of a Phase I

Answer 17

Records review, site visit, interviews, evaluation and reporting.

Question 18

What are sources of salt contamination?

Answer 18

Oil and gas wells, irrigation, roadways, naturally occurring in salty soils, excavation.

Question 19

Why is salt contamination a problem for vegetation?

Answer 19

Plants allow water into their roots across a semi-permeable membrane. This relies on a concentration gradient between the roots and soil. If soils are too saline, vegetation will be unable to absorb water.

Question 20

Define saline soils

Answer 20

Soil containing enough soluble salts to adversely impact plant growth.

Question 21

Define sodic soils

Answer 21

Contain clay particles and organics have a high sodium exchange ratio.

Question 22

How do sodic soils work?

Answer 22

Anions and cations absorb to clay surfaces and repel each other causing the clay to flocculate.

Question 23

What are the differences between normal and sodic soils.

Answer 23

normal soils are packed tightly, sodic soils are loose and crumbly because the salts bonding to the clay are causing a separation.

Question 24

What is a saline-sodic soil?

Answer 24

Soils with high concentrations of exchangeable Na but also high concentrations of other types. Saline conditions counter act the sodic conditions and prevent soil separation of clay particles but the soils still have enough salts to adversely impact vegetation health.

Question 25

What are the visible signs of salt contamination?

Answer 25

White crusts, erosion, healthy adult vegetation but no seedlings.

Question 26

What is the SAR

Answer 26

The SAR (Sodium adsorption ratio) measures the relative amount of sodium compound to calcium and magnesium. SAR=[Na]/(SQRT([Mg]+[Ca]/2))

Question 27

How are soils differentiated based on SAR and EC values?

Answer 27

Normal: EC >4 SAR >13
Saline: EC >4 SAR 13
Saline-Sodic EC >4 SAR >13

Question 28

How can Salt contamination be remediated?

Answer 28

Addition of calcium by gypsum (slow) or CaNO3 (fast) can be added. Turning/ mixing the soil, irrigation, leachate collection, time.

Question 29

Equivalent land capability

Answer 29

Ability of land to support uses after reclamation similar to the ability prior to the development.

Question 30

Reclamation certificate

Answer 30

Given once it is proved the land has returned to equivalent land capability.

Question 31

Decommisioning

Answer 31

Permanent closure of a facility followed by the dismantling of equipment, buildings and structures plus reclamation.

Question 32

Tier 1 guidlines

Answer 32

Acceptable levels for a series of potentially toxic materials

Question 33

Tier 2 guidelines

Answer 33

When assumptions at the site do not match the assumptions that were developed in Tier 1. Adjustments to tier 1 based on site specific conditions.

Question 34

Tier 3

Answer 34

Full risk assessment using learnt processes

Question 35

Soil particle size

Answer 35

> 75um Fine

<75um Coarse