Opinion: Environmental Assessment Crucial for Successful Urban Infill Projects


By Chris Spengler

With San Diego facing a housing shortage, ever increasing traffic congestion, and escalating construction costs, the answer seems to be higher density in already developed areas, otherwise known as urban infill. However, working on urban infill projects as opposed to “greenfields” — otherwise previously undeveloped land — comes with added issues, namely environmental contamination.

This contamination includes gasoline, diesel and oil leaking from underground storage tanks and pipelines, solvents from former industrial and automotive industries, toxic metals such as lead, arsenic and chromium, and burn ash that contains heavy metals, carcinogens and dioxins.

Opinion logoThere are three major issues with these contaminants that must be addressed: Do they pose a health risk to humans at the property? Do they pose a risk to the environment? What is the proper handling, management and disposal of contaminated soil and groundwater?

Given this daunting task, one would think that it is common practice for developers to expend considerable resources to understand the extent of contamination and in planning to address it before or during construction. But that’s not always the case.

There’s an old saying that “poor planning on your part does not necessitate an emergency on mine.” When it comes to construction and environmental contamination issues, the lack of proper planning will create an emergency for everyone involved. By emergency I mean budget-busting unanticipated costs, schedule-destroying delays, compounding change orders, missed milestones, stressed relationships, and agonizing uncertainty. All of this before the first cubic yard of concrete is poured.

The amount of planning for construction projects is phenomenal. Enormous resources are expended to estimate every aspect of the process, every cubic foot of concrete, pound of steel, inch of wire, square foot of drywall and so on. Then there’s the 3D modeling, building information modeling, mobile apps, 3D scanning and more.

However, when it comes to environmental contamination, doing the bare minimum and flying blind seems to be the “go to” approach for many developers. Putting the risk onto the construction manager or general contractor will unnecessarily increase costs. In any event, they may push back and insist the owner take on the risk.

This happens because planning for environmental issues during construction needs to begin before the construction starts, which means before the construction loan disbursements. Therefore, developers must pay with their own “soft money.” This leads to hiring consultants who promise the most for the least but deliver the worst in terms of assessment and plans.

The old rule for evaluating construction bids of throwing out the lowest and the highest is not a bad one for evaluating environmental bids. However, that assumes the scope of work is equal across the proposals and they rarely are. If consultants say they can assess an entire city block with only a handful of soil borings, it’s time for the buyer to beware.

A good assessment for an urban infill site is made up of three parts: A thorough understanding of the history of a site; effective sampling methods and frequency that correspond to the types of contamination suspected to be present; and a full understanding of the future land use and grading plans to understand and minimize the extent of remediation required.

Failures in one or more of these components are common, but can be avoided by doing more than the bare minimum. Here are three examples:

Failure to understand that historical residential land uses can result in contamination. From the 1800s into the early 1900s it was common to burn trash in the back lots of residential and some commercial properties, leaving behind burn ash, lead and carcinogens. The historical use of lead-based paint and aerially deposited lead from older gasoline can also result in the soil on historically residential properties being hazardous waste.

Using direct-push soil sampling, a method using a small diameter rod to collect soil samples, to assess a property for metals. Direct-push sampling severely limits detailed observations of the soil. Distinguishing fill soil from native soil is often the key to understanding the extent of the contamination.

Not correlating the project’s grading plans with the data to determine what contaminants will be left in-place versus what will be exported will likely result in poorly conceived remediation plans and lost opportunities to save money and time.

These principles were put to the test when I managed the assessment and remediation of the 19 city blocks for the Petco Park and East Village Remediation project. It began with a thorough assessment of the history of each property back to the late 1800s, and then individualized assessment and remediation plans were designed. The remediation of the first six blocks for the future ballpark was completed in three and a half months, and the remainder was completed ahead of the construction schedule. As a result of this thorough planning, there was never a need to go back for additional sampling to satisfy the regulatory agencies.

Too many times consultants choose to limit the effort they put into their assessments because of restrictive budgets. This results in too little historical research, too few sample points, reports without data plotted, and not enough budget for a true understanding of site conditions. Is this the right way to start that new $120 million condominium tower? It’s like asking your tailor to use as little thread as possible and then being surprised when the suit falls apart.

Just as the construction industry is moving to 3D modeling to avoid conflicts and design flaws, developers need to invest sufficiently in the environmental assessment so the consultant can develop a full 3D understanding of the subsurface that allows for the proper planning and execution of the remediation.

With a solid assessment and a well thought out plan, remediation costs can be kept to the bare minimum and schedules can be saved.

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