Establishing Health Risk-Based Redevelopment Constraints at a Brownfield Site
Amy Goldberg Day, LFR Inc., Emeryville, CA

Benefits of Brownfields Cleanup and Redevelopment: Case Study of Lowell, MA
Aleksandra Simic, ICF International, Fairfax, VA
Bansari Saha, ICF International, Lexington, MA
Barry Galef, ICF International, Fairfax, VA

Real Estate Transaction Completed/No Further Action Achieved using Soil Mixing with In-Situ Chemical Oxidation for Chlorinated Solvents
Maureen Dooley, Regenesis, Wakefield, MA
Bob Kelley, Ph.D., Regenesis, Plainfield, IL

Establishing Health Risk-Based Redevelopment Constraints at a Brownfield Site
Amy Goldberg Day, LFR Inc., 1900 Powell Street, 12th floor, Emeryville, CA 94608, Tel: 510-596-9507, Fax: 510-652-4906, Email: Amy.Goldberg.Day@LFR.com

As part of a Brownfield redevelopment evaluation, LFR Inc. conducted a human health risk assessment (HHRA) at the Proposed Docks Area Project site in Sacramento , California (“the Site”). The Site is located in the downtown area and is adjacent to the Sacramento River . It was formerly used for heavy industry, including a manufactured gas plant.

The HHRA evaluated potential exposures associated with the proposed redevelopment land uses, which included high-density residential, commercial, retail, and park. Current U.S. and California Environmental Protection Agency HHRA methodologies were used to estimate potential adverse health effects under the proposed site uses.

The goal of the HHRA was to develop health based building constraints to be used in the redevelopment design. As part of this goal, three building types were considered for both the residential and commercial conditions: slab-on-grade, subterranean parking, and podium parking. The different building types were evaluated to assess the need to also incorporate vapor intrusion mitigation measures into the redevelopment design. Groundwater data were used as the source concentration for the Johnson & Ettinger vapor transport model. Various modeling parameters were adjusted to replicate the building types.

The results of the HHRA indicated that direct contact to soil could be a health concern. In addition, the slab-on-grade construction could be a vapor intrusion concern in the one identified groundwater hot-spot area. However, the Site could be safely redeveloped if the identified constraints are incorporated into the redevelopment design. These include eliminating or significantly reducing direct soil contact, preventing the use of shallow groundwater as a domestic supply source, and avoiding the placement of slab-on-grade buildings over the one identified groundwater hot-spot area.

Benefits of Brownfields Cleanup and Redevelopment: Case Study of Lowell, MA
Aleksandra Simic, ICF International, 9300 Lee Highway, Fairfax , VA , 22031 , USA , Tel: 703-218-2514, Fax: 703-934-3270, Email: asimic@icfi.com
Bansari Saha, ICF International, 33 Hayden Avenue, Lexington , MA 02421 , USA , Tel: 781-676-4086, Fax: 781-676-4005, Email: bsaha@icfi.com
Barry Galef, ICF International, 9300 Lee Highway, Fairfax , VA , 22031 , USA , Tel: 703-934-3064, Fax: 703-934-3270, Email: bgalef@icfi.com

Over the past two decades, substantial research has been conducted on the effects of Superfund sites on human health and the environment.  Much less research has been done on the impacts of brownfields.  This asymmetry is not surprising; though brownfields vastly outnumber Superfund sites, the level of contamination at brownfields, if any, is perceived to pose a lower risk to humans and the environment than contamination at Superfund sites.  Another likely reason for a lack of literature on brownfields is that, before promulgation of the All Appropriate Inquiries rule by the U.S. Environmental Protection Agency (EPA), transactions of such properties have been complicated by liability concerns, so solid facts on brownfields cleanups and redevelopment are few and far between.  This study, developed for the US EPA/Office of Brownfields and Land Revitalization (OBLR), attempts to fill an important gap in the existing literature on benefits of contaminated land cleanup programs.  Due to extensive data needs, our research focuses on the city of Lowell , MA, which was chosen by EPA as a Brownfields Showcase Community in 1998.  The study asks two questions.  First, what effect did brownfields have on the local residential property values?  Second, what effect did activities aimed at reversing the negative impacts of brownfields have on the residential property values?  To answer these questions, we compiled a rich dataset from federal, state, and local government sources for the period 1990 to 2006.  Using hedonic housing price approach, we found that brownfields did have a significant negative effect on the residential properties in Lowell , and that property values rebounded completely post-EPA/OBLR grant award.  The study also examines what the appropriate measure of brownfield externalities is on residential property values. 

Real Estate Transaction Completed/No Further Action
Achieved using Soil Mixing with In-Situ Chemical Oxidation for Chlorinated Solvents
Maureen Dooley, Regenesis, 19 Belmont Road, Wakefield, MA 01880, USA, Tel: 781-245-1320, Fax: 781-245-1328, Email: mdooley@regenesis.com
Bob Kelley, Ph.D., Regenesis, 4813 Hyacinth Court, Plainfield, IL 60544, USA, Tel: 815-230-3516, Fax: 815-230-3517, E-mail: bkelley@regenesis.com

Chlorinated solvent contamination was detected in fill material throughout a 2-acre industrial property in Hollywood , California . Before a pending real estate transaction could be finalized, approximately 1 acre of the site required treatment for perchloroethene (PCE) and trichloroethene (TCE) in the vadose zone soil. To achieve this, chemical oxidation using RegenOx™ was selected based on the product’s proven effectiveness, low-cost, and handling safety. To complete the soil treatment, a total of 217,000 pounds of RegenOx was mechanically blended into the contaminated vadose soil using soil mixing equipment. This application method was favored because it maximized contact between RegenOx and the contaminated soil, achieving more rapid treatment when compared to using traditional direct-push technology. RegenOx was added in an 8-percent solution and mixed throughout the soil at a rate of 11 lbs/yd³. The 1-acre treatment area was sampled using a grid system (111 grids) for observed effectiveness. After a single ex-situ soil mixing treatment using RegenOx, 83 treatment grids impacted with chlorinated solvents were reduced to below the cleanup goal of 20 parts per billion (ppb). In 61 or of the 83 treatment grids, RegenOx reduced concentrations from as high as 140 ppb to below the cleanup goal with a single application. This treatment approach successfully treated nearly 18,000 yd³ of soil within 30 days for approximately $34/yd³, which included the costs for RegenOx, the soil mixer, and support equipment.  As a result the the California Regional Water Quality Control Board granted no further action and the pending real estate transaction was allowed to proceed to completion.  We will discuss the design details for this site as well as the lessons learned about combining chemical oxidation with soil mixing technologies for rapid closure of contaminated sites.