The usability of the IR,RAC and MRI indices of heavy metal distribution to assess the environmental quality of sewage sludge composts

To assess the environmental quality of compost, it is insufficient to use only total metal concentration. Therefore in this study, the stability of metals in compost and the environmental risk they pose were assessed by three indices that have been proposed for soils or sediments: the I_R, the RAC and the MRI. In mature composts, the highest bonding intensity was for Ni (0.79 < I_R < 0.93), then for Cu (0.56 < I_R < 0.65) and Pb (0.55 < I_R < 0.73), and the lowest for Zn (0.19 < I_R < 0.25). Although, both the I_R and the RAC are useful indices for evaluating the mobility of metals, they do not take into account their toxicity. Therefore, the overall classification of compost should also include the MRI, at which metal toxicity from the most available fractions is considered. Based on the MRI ranged between 10.0 and 11.6, all composts evaluated posed a low risk.     

Estimating the amount of WEEE generated in South Korea by using the population balance model

We estimated the amount of waste electrical and electronic equipment (WEEE) generated in South Korea by using the population balance model (PBM) based on a lifespan distribution analysis. This is the first study to apply PBM to estimate WEEE generation in South Korea. The lifespan distribution analysis of electrical and electronic equipment (EEE) was based on the results of a questionnaire survey of 1000 households, which were analyzed with the Weibull distribution. As a result, we could estimate the domestic service lifespan and lifespan distribution shape parameter for eight selected products. Using the lifespan distribution analysis and other data, such as the shipment volume and the number of products owned by households, we estimated the amount of WEEE generated for the eight selected items from 2000 to 2020. We found that 1.2 million air conditioners, 2.5 million televisions, 1.3 million microwave ovens, 1.2 million kimchi refrigerators, 17.0 million mobile phones, 1.7 million refrigerators, 2.0 million vacuum cleaners, and 1.4 million washing machines were generated as WEEE in 2010. We also compared our WEEE estimates with the number of items collected through the official WEEE recycling program from 2003 to 2009 and found that in 2009 washing machines had the highest collection rate (28%) and air conditioners had the lowest rate (7%).     

Greenhouse gas emissions from landfill leachate treatment plants: A comparison of young and aged landfill

With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH₄ emissions were observed from the fresh leachate storage pond, with the fluxes values (2219–26,489 mg C m^?2 h^?1) extremely higher than those of N₂O (0.028–0.41 mg N m^?2 h^?1). In contrast, the emission values for both CH₄ and N₂O were low for the aged leachate tank. N₂O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8–12% of the removal of N-species gases. Per capita, the N₂O emission based on both leachate treatment systems was estimated to be 7.99 g N₂O–N capita^?1 yr^?1. An increase of 80% in N₂O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO₂, with a small portion as CH₄ (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO₂ eq yr^?1, respectively, for a total that could be transformed to 9.09 kg CO₂ eq capita^?1 yr^?1.     

VFA and ammonia from residential food waste as indicators of odor potential

Research was conducted to determine suitable chemical parameters as indicators of odor from decomposing food wastes. Prepared food scraps were stored in 18 l plastic buckets (2 kg wet weight each) at 20 °C and 8 °C to reproduce high and low temperature conditions. After 1, 3, 7, 10 and 14 days of storage, the odor from the buckets were marked to an intensity scale of 0 (no odor) to 5 (intense) and the corresponding leachate analyzed for volatile fatty acids, ammonia and total organic carbon. A linear relationship between odor intensity and the measured parameter indicates a suitable odor indicator. Odor intensified with longer storage period and warmer surroundings. The study found ammonia and isovaleric acid to be promising odor indicators. For this food waste mixture, offensive odors were emitted if the ammonia and isovaleric acid contents exceeded 360 mg/l and 940 mg/l, respectively.     

Decomposition of forest products buried in landfills

The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5 yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C + H) loss of up to 38%, while loss for the other wood types was 0–10% in most samples. The C + H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27 g OC g^?1 dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than previously reported.     

GHG emission factors developed for the collection,transport and landfilling of municipal waste in South African municipalities

Greenhouse gas (GHG) emission factors are used with increased frequency for the accounting and reporting of GHG from waste management. However, these factors have been calculated for developed countries of the Northern Hemisphere and are lacking for developing countries. This paper shows how such factors have been developed for the collection, transport and landfilling of municipal waste in South Africa. As such it presents a model on how international results and methodology can be adapted and used to calculate country-specific GHG emission factors from waste. For the collection and transport of municipal waste in South Africa, the average diesel consumption is around 5 dm³ (litres) per tonne of wet waste and the associated GHG emissions are about 15 kg CO₂ equivalents (CO₂ e). Depending on the type of landfill, the GHG emissions from the landfilling of waste have been calculated to range from ?145 to 1016 kg CO₂ e per tonne of wet waste, when taking into account carbon storage, and from 441 to 2532 kg CO₂ e per tonne of wet waste, when carbon storage is left out. The highest emission factor per unit of wet waste is for landfill sites without landfill gas collection and these are the dominant waste disposal facilities in South Africa. However, cash strapped municipalities in Africa and the developing world will not be able to significantly upgrade these sites and reduce their GHG burdens if there is no equivalent replacement of the Clean Development Mechanism (CDM) resulting from the Kyoto agreement. Other low cost avenues need to be investigated to suit local conditions, in particular landfill covers which enhance methane oxidation.     

Measurement of carbon storage in landfills from the biogenic carbon content of excavated waste samples

Landfills are an anaerobic ecosystem and represent the major disposal alternative for municipal solid waste (MSW) in the U.S. While some fraction of the biogenic carbon, primarily cellulose (Cel) and hemicellulose (H), is converted to carbon dioxide and methane, lignin (L) is essentially recalcitrant. The biogenic carbon that is not mineralized is stored within the landfill. This carbon storage represents a significant component of a landfill carbon balance. The fraction of biogenic carbon that is not reactive in the landfill environment and therefore stored was derived for samples of excavated waste by measurement of the total organic carbon, its biogenic fraction, and the remaining methane potential. The average biogenic carbon content of the excavated samples was 64.6 ± 18.0% (average ± standard deviation), while the average carbon storage factor was 0.09 ± 0.06 g biogenic-C stored per g dry sample or 0.66 ± 0.16 g biogenic-C stored per g biogenic C_.     

Sustainable sanitary landfills for neglected small cities in developing countries: The semi-mechanized trench method from Villanueva,Honduras

Open dumping is the most common practice for the disposal of urban solid wastes in the least developed regions of Africa, Asia and Latin America. Sanitary landfill design and operation has traditionally focused on large cities, but cities with fewer than 50,000 in population can comprise from 6% to 45% of a given country’s total population. These thousands of small cities cannot afford to operate a sanitary landfill in the way it is proposed for large cities, where heavy equipment is used to spread and compact the waste in daily cells, and then to excavate, transport and apply daily cover, and leachate is managed with collection and treatment systems. This paper presents an alternative approach for small cities, known as the semi-mechanized trench method, which was developed in Villanueva, Honduras. In the semi-mechanized trench method a hydraulic excavator is used for 1–3 days to dig a trench that will last at least a month before it is filled with waste. Trucks can easily unload their wastes into the trench, and the wastes compact naturally due to semi-aerobic biodegradation, after which the trenches are refilled and covered. The exposed surface area is minimal since only the top surface of the wastes is exposed, the remainder being covered by the sides and bottom of the trench. The surplus material from trench excavation can be valorized for use as engineering fill onsite or off. The landfill in Villanueva has operated for 15 years, using a total land area of approximately 11 ha for a population that grew from 23,000 to 48,000, with a land requirement of 0.2 m²/person year, a cover to waste ratio of 0.2, and an estimated soil surplus of 298,000 m³ that is valorized and used onsite. The landfill has been operated solely by the municipality with an operational cost in 2010 estimated at US$4.60 per ton. A modified water balance analysis at Villanueva shows negligible leachate generation from covered trenches and 700 m³/yr (60 m³/ha yr) from the two open trenches required for daily operation. If the site were an open dump, however, leachate generation is estimated to be 3900 m³/ha yr and contaminated runoff 5000 m³/ha yr. A simple model used to estimate dilution of generated leachate based on groundwater flow data and aquifer stratigraphy suggests that the leachate will be diluted by a factor of 0.01 in the aquifer. Leachate contaminants will not accumulate because the aquifer discharges to the Ulua River 2 km south of the landfill. While not suitable for all sites, the Villanueva method nevertheless serves as an excellent example of how a small city landfill with natural compaction of waste and attenuation of leachate can be sustainably operated.     

Impact of nitrate-enhanced leachate recirculation on gaseous releases from a landfill bioreactor cell

This study evaluates the impact of nitrate injection on a full scale landfill bioreactor through the monitoring of gaseous releases and particularly N₂O emissions. During several weeks, we monitored gas concentrations in the landfill gas collection system as well as surface gas releases with a series of seven static chambers. These devices were directly connected to a gas chromatograph coupled to a flame ionisation detector and an electron capture detector (GC-FID/ECD) placed directly on the field. Measurements were performed before, during and after recirculation of raw leachate and nitrate-enhanced leachate. Raw leachate recirculation did not have a significant effect on the biogas concentrations (CO₂, CH₄ and N₂O) in the gas extraction network. However, nitrate-enhanced leachate recirculation induced a marked increase of the N₂O concentrations in the gas collected from the recirculation trench (100-fold increase from 0.2 ppm to 23 ppm). In the common gas collection system however, this N₂O increase was no more detectable because of dilution by gas coming from other cells or ambient air intrusion. Surface releases through the temporary cover were characterized by a large spatial and temporal variability. One automated chamber gave limited standard errors over each experimental period for N₂O releases: 8.1 ± 0.16 mg m^?2 d^?1 (n = 384), 4.2 ± 0.14 mg m^?2 d^?1 (n = 132) and 1.9 ± 0.10 mg m^?2 d^?1 (n = 49), during, after raw leachate and nitrate-enhanced leachate recirculation, respectively. No clear correlation between N₂O gaseous surface releases and recirculation events were evidenced. Estimated N₂O fluxes remained in the lower range of what is reported in the literature for landfill covers, even after nitrate injection.     

Evolution of butyric acid and the methanogenic microbial population in a thermophilic dry anaerobic reactor

Knowledge of the relationship between the evolution of butyric acid, the main precursor of methane, and the methanogenic microbial population, quantified by fluorescent in situ hybridization (FISH), is important for understating and controlling the anaerobic digestion of solid waste. In this study, a statistical analysis has been made of this relationship in a laboratory-scale continuously stirred tank reactor (CSTR) without recycling of biomass. The CSTR has been operated at four organic loading rates (OLR) between 4.42 and 7.50 kg VS m^?3 day^?1, using the Organic Fraction of Municipal Solid Waste (OFMSW) as the substrate. During the start-up stage, the consumption of butyric acid is related to the population of H₂-utilising methanogens (R² = 0.774), whereas in the stabilization stage, it is related to that of acetoclastic methanogens (R² = 0.716). Therefore, it can be concluded that the methanogenic population dynamics are closely correlated with the concentration of volatile fatty acids, and in particular, with that of butyric acid.     

The operation of cost-effective on-site process for the bio-treatment of mixed municipal solid waste in rural areas

The application of on-site waste treatment significantly reduces the need for expensive waste collection and transportation in rural areas; hence, it is considered of fundamental importance in developing countries. In this study, the effects of in-field operation of two types of mini-scale on-site solid waste treatment facilities on de-centralized communities, one using mesophilic two-phase anaerobic digestion combined with composting (TPAD, 50 kg/d) and another using decentralized composting (DC, 0.6–2 t/d), were investigated. Source-separated collection was applied to provide organic waste for combined process, in which the amount of waste showed significant seasonal variation. The highest collection amount was 0.18 kg/capital day and 0.6 kg/household day. Both sites showed good performance after operating for more than 6 months, with peak waste reduction rates of 53.5% in TPAD process and 63.2% in DC process. Additionally, the windrow temperature exceeded 55 °C for >5 days, indicating that the composting products from both facilities were safe. These results were supported by 4 days aerobic static respiration rate tests. The emissions were low enough to avoid any impact on nearby communities (distance <100 m). Partial energy could be recovered by the combined process but with complicated operation. Hence, the choice of process must be considered in case separately.     

Effect of nine years of animal waste deposition on profile distribution of heavy metals in Abeokuta,south-western Nigeria and its implication for environmental quality

Uncontrolled deposition of waste from animal farms is a common practice in south-western Nigeria, and the presence of heavy metals in soil constitutes environmental and health hazards by polluting the soil, ground water, adjoining streams and rivers. The study investigated the profile distribution of Mn, Pb, Cd, Zn, Fe, Cu, Ni and Cr in some tropical Alfisols in south-western Nigeria after nine years disposal of animal wastes. The amount of these metals in the soil horizons was high enough to cause health and phytotoxic risks. All the metals except Zn and Cr increased down the profile, while Mn, Pb, Cd, Fe, Cu and Ni accumulated at 80–120 cm depth. The increment of these metals at this depth over the top soil were 26%, 143%, 72%, 47%, 328% for Mn, Pb, Cd, Cu and Ni, respectively. It thus, shows their mobility and the possibility of polluting ground water. The Mn content at the poultry and cattle waste sites increased by 127% and 25%, respectively over the control, while that of cattle and swine dump site for Cd content were 9.82 and 15.63 mg kg^?1, respectively. Lead content also increased by 8.52 and 5.25 mg kg^?1, respectively.There was the accumulation of Zn and Cu at the swine dump site while the cattle dump site had the highest amounts of nickel and chromium. The least amount of Fe was recorded at the swine waste dump site. The reduction in organic matter with depths together with the reduced pH might have favored the mobility of the metals. The ranking of pollution among the sites was poultry > swine > cattle > sheep and could be due to the type of ration fed, the vaccination programmes, sanitation programmes and other management practices.     

Pathogen reduction in minimally managed composting of bovine manure

Spread of manure pathogens is of considerable concern due to use of manure for land application. In this study, the effects of four static pile treatment options for bovine manure on die-off of a generic Escherichia coli, E. coli O157:H7 surrogate, Salmonella Senftenberg, Salm. Typhimurium, and Listeria monocytogenes were evaluated. Bovine manure spiked with these bacteria were placed in cassettes at the top, middle, and bottom sections of four static pile treatments that reflect minimal changes in pile construction with and without straw. Temperatures were monitored continuously during the 28 day self-heating period. E. coli and salmonellae were reduced from 8 to 9 log₁₀ CFU g^?1 to undetectable levels (<1.77 log₁₀ MPN g^?1) at 25–30 cm depths within 7 days in all pile sections except for the manure-only pile in which 3–4 logs of reduction were obtained. No L. monocytogenes initially present at 6.62 log₁₀ CFU g^?1 were recovered from straw-amended piles after 14 days, in contrast with manure-only treatment in which this pathogen was recovered even at 28 days. Decline of target bacterial populations corresponded to exposure to temperatures above 45 °C for more than 3 days and amendments of manure with straw to increase thermophilic zones. Use of straw to increase aeration, self-heating capacity, and heat retention in manure piles provides producers a minimal management option for composting that enhances pathogen die-off and thereby reduces risk of environmental spread when manure is applied to land.     

Two-year performance by evapotranspiration covers for municipal solid waste landfills in northwest Ohio

Evapotranspiration (ET) covers have gained interest as an alternative to conventional covers for the closure of municipal solid waste (MSW) landfills because they are less costly to construct and are expected to have a longer service life. Whereas ET covers have gained acceptance in arid and semi-arid regions (defined by a precipitation (P) to potential evapotranspiration (PET) ratio less than 0.75) by meeting performance standards (e.g. rate of percolation), it remains unclear whether they are suitable for humid regions (P:PET greater than 0.75). The goal of this project is to extend their application to northwest Ohio (P:PET equals 1.29) by designing covers that produce a rate of percolation less than 32 cm yr^?1, the maximum acceptable rate by the Ohio Environmental Protection Agency (OEPA). Test ET covers were constructed in drainage lysimeters (1.52 m diameter, 1.52 m depth) using dredged sediment amended with organic material and consisted of immature (I, plants seeded onto soil) or mature (M, plants transferred from a restored tall-grass prairie) plant mixtures. The water balance for the ET covers was monitored from June 2009 to June 2011, which included measured precipitation and percolation, and estimated soil water storage and evapotranspiration. Precipitation was applied at a rate of 94 cm yr^?1 in the first year and at rate of 69 cm yr^?1 in the second year. During the first year, covers with the M plant mixture produced noticeably less percolation (4 cm) than covers with the I plant mixture (17 cm). However, during the second year, covers with the M plant mixture produced considerably more percolation (10 cm) than covers with the I plant mixture (3 cm). This is likely due to a decrease in the aboveground biomass for the M plant mixture from year 1 (1008 g m^?2) to year 2 (794 g m^?2) and an increase for the I plant mixture from year 1 (644 g m^?2) to year 2 (1314 g m^?2). Over the 2-year period, the mean annual rates of percolation for the covers with the M and I plant mixtures were 7 and 8 cm yr^?1, which are below the OEPA standard. The results suggest the application of ET covers be extended to northwest Ohio and other humid regions.     

The impact of tourism on municipal solid waste generation: The case of Menorca Island (Spain)

Tourism can sustain high levels of employment and income, but the sector is a source of environmental and health impacts. One of the most important is the generation of municipal solid waste (MSW). However, there is a lack of studies which quantify how much the tourist population engages in total MSW and separately collected recyclables. The aim of this paper is to estimate the impact of the tourist population on MSW, both total and separately collected, for the period 1998–2010, for the Mediterranean island of Menorca (Spain). We use dynamic regressions models, including data for monthly stocks of tourists. The results show that, on average, a 1% increase in the tourist population in Menorca causes an overall MSW increase of 0.282% and one more tourist in Menorca generates 1.31 kg day^?1 (while one more resident generates 1.48 kg day^?1). This result could be useful to better estimate the seasonal population of different regions, since intrannual fluctuation of MSW is used as a proxy measure of actual population (the sum of residents and tourists). Moreover, an increase of 1% in the tourist population causes an increase of 0.232% in separately collected recyclables and an additional tourist generates 0.160 kg day^?1. One resident selectively collects on average 47.3% more than one tourist. These results can help in the planning of waste infrastructure and waste collection services in tourist areas.     

Dimensional and chemical characterization of particles at a downwind receptor site of a waste-to-energy plant

In the last years numerous epidemiological studies were carried out to evaluate the effects of particulate matter on human health. In industrialized areas, anthropogenic activities highly contribute to the fine and ultrafine particle concentrations. Then, it is important to characterize the evolution of particle size distribution and chemical composition near these emission points. Waste incineration represents a favorable technique for reducing the waste volume. However, in the past, municipal waste incinerators (MWIs) had a bad reputation due to the emission of toxic combustion byproducts. Consequently, the risk perception of the people living near MWIs is very high even if in Western countries waste incineration has nowadays to be considered a relatively clean process from a technical point of view. The study here presented has an exemplary meaning for developing appropriate management and control strategies for air quality in the surrounding of MWIs and to perform exposure assessment for populations involved. Environment particles were continuously measured through a SMPS/APS system over 12 months. The monitoring site represents a downwind receptor of a typical MWI. Furthermore, elements and organic fractions were measured by means of the Instrumental Neutron Activation Analysis and using dichotomous and high volume samplers. Annual mean values of 8.6 × 10³ ± 3.7 × 10² part. cm^?3 and 31.1 ± 9.0 μg m^?3 were found for number and mass concentration, typical of a rural site. Most of the elements can be attributed to long-range transport from other natural and/or anthropogenic sources. Finally, the Polycyclic Aromatic Hydrocarbons present low concentrations with a mean value of 24.6 ng m^?3.     

Performance evaluation of a completely stirred anaerobic reactor treating pig manure at a low range of mesophilic conditions

Many Chinese biogas plants run in the lower range of mesophilic conditions. This study evaluated the performance of a completely stirred anaerobic reactor treating pig manure at different temperatures (20, 28 and 38 °C). The start-up phase of the reactor at 20 °C was very long and extremely poor performance was observed with increasing organic loading rate (OLR). At an OLR of 4.3 g ODM L^?1 d^?1, methane production at 28 °C was comparable (3% less) with that at 38 °C, but the risk of acidification was high at 28 °C. At low OLR (1.3 g ODM L^?1 d^?1), the biogas process appeared stable at 28 °C and gave same methane yields as compared to the reactor operating at 38 °C. The estimated sludge yield at 28 °C was 0.065 g VSS g^?1 COD_removed, which was higher than that at 38 °C (0.016 g VSS g^?1 COD_removed).     

Impacts of industrial waste resources on maize (Zea mays L.) growth,yield, nutrients uptake and soil properties

Discharging untreated highly acidic (pH < 4.0), organic and nutrients rich monosodium glutamate wastewater (MW), and highly alkaline (pH > 10.0) paper-mill wastewater (PW) causes environmental pollution. When acidity of MW neutralized (pH 6.5 ± 0.1) with PW and lime (treatments represented as MW + PW and MW + Lime), then MW may be utilized as a potential source of nutrients and organic carbon for sustainable food production. Objectives of this study were to compare the effects of PW and lime neutralized MW and chemical fertilizers on maize (Zea mays L. cv. Snow Jean) plant growth, yield, nutrients uptake, soil organic matter and humic substances. The field experiment was carried out on maize using MW at 6000 L ha^?1. Impacts of the MW application on maize crop and soil properties were evaluated at different stages. At harvest, plant height, and plant N and K uptake were higher in MW treatment. Leaf area index at 60 days after sowing, plant dry matter accumulation at harvest, and kernels ear^?1 and 100-kernel weight were higher in MW + Lime treatment. Kernel N, P, K, Mn, Fe and Zn, and plant Zn uptake were highest in MW + Lime. Plant Fe uptake, and soil organic matter and humic substances were highest in MW + PW. The MW + PW and MW + Lime treatments exhibited comparable results with chemically fertilized treatment. The MW acidity neutralized with lime showed positive impacts on growth, yield and nutrients uptake; nevertheless, when MW pH neutralized with PW has an additional benefit on increase in soil organic matter and humic substances.     

Evaluating the effect of vehicle impoundment policy on illegal construction and demolition waste dumping: Israel as a case study

Construction and demolition (C&D) waste dumped alongside roads and in open areas is a major source of soil and underground water pollution. Since 2006, Israeli ministry for environmental protection enacted a policy of vehicle impoundment (VI) according to which track drivers caught while dumping C&D waste illegally have their vehicles impounded. The present study attempted to determine whether the VI policy was effective in increasing the waste hauling to authorized landfill sites, thus limiting the number of illegal unloads of C&D waste at unauthorized landfill sites and in open areas. During the study, changes in the ratio between the monthly amount of C&D waste brought to authorized landfills sites and the estimated total amount of C&D waste generated in different administrative districts of Israel were examined, before and after the enactment of the 2006 VI policy. Short questionnaires were also distributed among local track drivers in order to determine the degree of awareness about the policy in question and estimate its deterrence effects. According to the study’s results, in the district of Haifa, in which the VI policy was stringently enacted, the ratio between C&D waste, dumped in authorized landfill sites, and the total amount of generated C&D waste, increased, on the average, from 20% in January 2004 to 35% in October 2009, with the effect attributed to the number of vehicle impoundments being highly statistically significant (t = 2.324; p < 0.05). By contrast, in the Jerusalem and Southern districts, in which the VI policy was less stringently enforced, the effect of VI on the above ratio was found to be insignificant (p > 0.1). The analysis of the questionnaires, distributed among the local truck drivers further indicated that the changes observed in the district of Haifa are not coincident and appeared to be linked to the VI policy’s enactment. In particular, 62% of the truck drivers, participated in the survey, were aware of the policy and 47% of them personally knew a driver whose vehicle was impounded. Furthermore, the drivers estimated the relative risk of being caught for unloading C&D waste in unauthorized sites, on the average, as high as 67%, which is likely to become a deterrent on its own. Our conclusion is that the VI policy appears to have a deterring effect on truck drivers, by encouraging them to haul C&D waste to authorized landfill sites. As we suggest, the research methodology implemented in the study and its results may help policy makers in other regions and countries, which experience similar environment enforcement problem, to analyze policy responses.