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On the eff ectiveness in implementing a waste management plan method in construction Vivian W Y Tam Griffi th School of Engineering Griffi th University PMB 50 Gold Coast Mail Centre QLD 9726 Australia Accepted 16 April 2007 Abstract The increasing awareness of waste management concerns from construction and demolition waste has led to the development of waste management as an important function of construction project management The Hong Kong government started employing the imple mentation of a waste management plan WMP method for all construction projects in 2003 During the trial period the government received diff erent version of feedback from the industry It also came out that detailed descriptions of waste management procedures in the WMP method largely aff ect the productivity of companies This paper investigates the eff ectiveness of the existing implementation of the WMP method in the Hong Kong construction industry A questionnaire survey and structured interviews were conducted The result showed that Propose methods for on site reuse of materials and Propose methods for reducing waste are the main benefi ts gained from the implementation of the WMP method However Low fi nancial incentive and Increase in overhead cost are consid ered as the major diffi culties in the implementation From that Use of prefabricated building components is considered as the major eff ective measure to encourage the implementation of the WMP method 2007 Elsevier Ltd All rights reserved 1 Introduction Waste management in the construction industry has not been successfully controlled and much more work is required to achieve a satisfactory standard In the past construction waste was commonly disposed in landfi lls However as landfi ll areas are expected to run out in the next few years Hong Kong Government Environmental Protection Department 2006 there is an urgent need to discover other methods to manage waste The Hong Kong government has employed various measures to control waste in the past few years including adopting a waste disposal ordinance launching a green manager scheme drafting a waste reduction framework plan commissioning a pilot concrete recycling plant stipu lating the implementation of a waste management plan WMP method and promoting a public landfi ll charging scheme Hong Kong Government 2006 Among these measures the newly employed scheme using the WMP method has received negative feedback from the industry Construction organizations commented on the detailed descriptions of waste management procedures in the WMP method which largely aff ect their productivity showing the ineff ectiveness of using the method in con struction projects This paper focuses on examining waste generation in construction and the existing waste controlling measures employed by the Hong Kong government exploring the eff ectiveness and diffi culties of the existing WMP method and proposing ways to improve the existing problems in implementing the WMP method 2 Existing waste controlling methods There has been an overwhelming promotion of waste management tools and sustainable development activities in recent years As a result there is a growing awareness of 0956 053X see front matter 2007 Elsevier Ltd All rights reserved doi 10 1016 j wasman 2007 04 007 Tel 61 07 5552 9278 fax 61 07 5552 8065 E mail address v tam griffi th edu au Waste Management xxx 2007 xxx xxx Please cite this article in press as Tam V W Y On the eff ectiveness in implementing a waste management plan Waste Manage ment 2007 doi 10 1016 j wasman 2007 04 007 ARTICLE IN PRESS wastemanagementissuesandthepotentialproblemsrelated to the negative impacts on the environment Generally speaking construction is not an environmentally friendly activity Comprehensive reviews were encouraged to pro vide waste management measures in construction activities Tam et al 2005b 2006 Various factors are aff ecting the environment whichincludelanduseandlanddeterioration resource depletion waste generation and various forms of pollution Tam et al 2005a 2006 Debris from construction and demolition projects con stitutes a large proportion of solid waste as shown in Table 1 In the United Kingdom more than 50 of land fi ll waste come from construction Ferguson et al 1995 while 70 million tons of waste is from construction and demolition activities annually Sealey et al 2001 In Australia about 14 million tons of waste have been land fi lled annually and 44 of the total waste is attributed to the construction industry Craven et al 1994 McDon ald 1996 In the United States of America around 29 of solid waste is from construction Hendriks and Pietersen 2000 and in Hong Kong about 38 of solid waste come from the construction industry Hong Kong Government Environmental Protection Department 2006 Several measures have been implemented under gov ernmentinitiativestohelpreducewastegeneration including i enactment of the Waste Disposal Ordi nance ii issuance of a white paper for a comprehensive 10 yr plan to reduce construction waste iii launching of a green manager scheme iv issuance of a practical note on the use of recycled aggregate v commission a pilot recycling plant to supply recycled aggregate to public projects vi issuance of a circular on waste manage ment and vii implementation of a charge for waste dumping The Hong Kong government has implemented various types of regulations and methods which aim at minimiz ing waste production and thus improving the environ ment Amongthem themandatorysystemin implementing the WMP method for all construction pro jects has received diff erent types of feedback during its trial period Some contractors found that the WMP method was useful and eff ective The management of the contractor required its site staff to carry out monthly reviews to ensure that operations on site follow the plan provided Poon et al 2004a b However some argued that detailed descriptions of waste management proce dures in the WMP method signifi cantly aff ect the produc tivity of companies Many construction organizations lack experience in drafting and using the WMP method The companies also found diffi culties in recycling construction materials on site The next section undertakes a survey to study the eff ec tiveness of implementing the WMP method Benefi ts and diffi culties in implementing the WMP method will be con sidered Recommended measures to eff ectively implement the WMP method are also proposed 3 Research methodology To examine the eff ectiveness of the existing requirements in implementing the WMP method for all construction pro jects a questionnaire survey was conducted A copy of the questionnaire is included in Appendix 1 The survey was Table 1 Comparison of construction waste concentration in various countries CountryConcentration of Construction waste in total waste in C A is the highest weight in this study A 5 N the total number of samples and RII the relative important index 0 6 RII 6 1 After receiving the questionnaire responses individual structured interviews were arranged with eight respon dents selected from diff erent business sectors one from a government department one building developer one envi ronmental consultant two registered building contractors two registered specialized contractors and one member of an environmental professional association The interviews were intended for gathering further comments elaboration and interpretation on the results obtained from the ques tionnaire and reducing the limitation of low response rates from G4 and G5 4 Results 4 1 Attitudes in implementing waste management FromtheresultsshowninTable3 itcanbeseenthatcon crete construction is the major source of construction waste corresponding to about 28 9 of the total construction waste This result is consistent with the fi ndings of Li 2002 Concrete was found to be the most signifi cant ele ment comprising about 75 of waste from construction sites 70 from demolition site 40 from general civil work and 70 from renovation work An interviewed govern mental staff pointed out that recovering concrete waste for use as recycled aggregate and as new concrete construction materials is a new direction in the construction industry This can provide good opportunities to reduce landfi ll dis posal and thus improve the environment In considering the willingness of the various stakehold ers to minimize waste generation the results show that gov ernmenthasthestrongestwillingnesstominimize construction waste generation at about 78 9 see Table 4 From the interview discussions with a contractor he explained that implementing a waste management program requires the investment of a large amount of money in the early stages of projects including implementing site plan ning using environmentally friendly materials and install ing waste management facilities and equipment which are the main obstacles aff ecting his willingness to minimize waste generation Among fi ve major project factors cost time quality environmental and safety most of the respondents pointed out that minimizing construction cost is the most important project goal while environmental concern is the least important factor see Table 5 One of the contrac tors explained that having a low tendering price can eff ec tivelyhelpthemtobeawardedprojects andthat companies can also increase profi ts if they can lower the construction cost A member of environmental profes sional associations group argued that implementing a waste management program can help in achieving a Table 2 Distribution of survey respondents GroupDescriptionNumberPercentage G1Registered general building contractor3444 7 G2Registered specialist contractor2228 9 G3Consultant1013 2 G4Governmental department and developer 56 6 G5Environmental professional association56 6 Total76100 Table 3 Survey results on major sources of construction waste Major sources of construction wastePercentage Concrete construction28 9 Steel reinforcement bar21 1 Formwork15 8 Temporary hoarding14 0 Scaff olding7 9 Material handling7 0 Finishing5 3 Total100 0 Table 4 Survey result on willingness to minimize waste generation Willingness to minimize waste Contractor Client Designer Government Yes26 318 421 178 9 Neutral57 955 347 315 8 No15 826 331 65 3 Total100 0100 0100 0100 0 V W Y Tam Waste Management xxx 2007 xxx xxx3 ARTICLE IN PRESS Please cite this article in press as Tam V W Y On the eff ectiveness in implementing a waste management plan Waste Manage ment 2007 doi 10 1016 j wasman 2007 04 007 long term cost savings goal although it increases the short time investment cost A government staff member agreed that the lowest tendering price is commonly con sidered as the most important factor in awarding a pro ject however a new trend from the government in promoting all tendering contractors is to require enough documentationofwastemanagementconsciousness including the implementation of an ISO 14000 environ mental management system From Table 6 it highlighted that only around 60 5 of the respondents agreed that the implementation of the WMP method can help in reducing waste production A member from an environmental professional association pointed out that the association had received assistance in implementing the method from construction organiza tions It is clear that those construction organizations lack experience in using the WMP method for their projects Once suffi cient experience in using the method is gained waste disposal levels will be lowered From Table 6 it can be seen that more than half of the respondents agreed that implementing the WMP method can help in minimizing waste generation It also showed that around half of the respondents 47 4 are dissatisfi ed with the existing implementation of the method in their companies During the interview discussions with a build ing contractor and a specialized contractor they explained that most of the construction organizations lack experience in implementing the method such that it takes a long time to draft their WMP methods On site applications also aff ect implementation of the method which need to be con tinuously revised A member of the environmental profes sional associations group recommended that periodic auditing of waste generation from various construction activities can help construction organizations in providing an early on site waste management plan and in making modifi cations on the existing management system The audits should address all aspects of waste related activities including waste generation storage recycling transport and disposal 4 2 Benefi ts in implementing the WMP method The implementation of the WMP method has several benefi ts Pollutionprevention betterallocationof resources better regulatory compliance evaluation of risks and plans for preventing potential problems can be achieved through implementation of the method Tibor 1996 Previous studies have identifi ed a number of benefi ts in implementing the WMP method for construction Jasch 2000 Kuhre 1998 Tam et al 2006 A list of benefi ts can be seen in Table 7 with the ranking by the relative impor tance index From the results of F statistics all of the benefi ts are consistent among the fi ve groups of respondents It is clear that all groups are providing the same arguments on the benefi ts in implementing the WMP method Table 6 survey results on reducing waste production in implementing a waste management plan method ResponsesReducing waste production in implementing a WMP Method in Satisfaction on WMP in Yes60 513 2 Neutral29 039 5 No10 547 4 Table 7 Relative importance index for benefi ts in implementing a WMP method Benefi ts in implementing a WMP method Pw Relative importance indexRanking Propose methods for reducing waste2920 7681 Propose methods for on site reuse of materials2920 7681 Propose methods for on site waste separation2900 7633 Propose disposal outlets2840 7474 Identify diff erent types of waste2760 7265 Propose methods of dealing with packing materials2620 6896 Develop an organization structure for waste management2560 6747 Estimate quantities of waste requiring off site disposal2540 6688 Help implementing trip ticket system2480 6539 Monitor and audit waste management programme2460 64710 Propose methods of processing storing and disposal of hazardous waste2460 64710 Estimate quantities of identifi ed waste2400 63212 Propose areas for waste storage2220 58413 Propose lists of materials to be reused or recycled2200 57914 Table 5 Survey results on project goal of construction projects Project goal of construction projects Most important Least important Cost39 55 3 Time15 818 4 Quality18 415 8 Environmental0 0047 4 Safety26 313 2 Total100 0100 0 4V W Y Tam Waste Management xxx 2007 xxx xxx ARTICLE IN PRESS Please cite this article in press as Tam V W Y On the eff ectiveness in implementing a waste management plan Waste Manage ment 2007 doi 10 1016 j wasman 2007 04 007 The survey results show that Propose methods for on site reuse of materials and Propose methods for reducing waste are recognized as the most important benefi tsinimplementingtheWMPmethod which requires a detailed procedure in showing how construc tion organizations reuse recycle and reduce construction waste before starting their projects A registered building contractor pointed out that he designed a detailed meth odology for reusing recycling and reducing major types of construction waste to implement the method including concrete tiles steel glass and plastic He claimed that these reuse recycling and reducing methods can be eff ec tively used in planning the use of materials and reducing material consumption Some local examples in material recycling are also recommended by the Hong Kong gov ernment Hong Kong Government Environmental Pro tection Department 2006 for example using recycled aggregate as sub base material for road construction using asphalt as aggregate fi ll and sub base and using glass as a substitute for sand and aggregate as pipe bed ding material However Propose lists of materials to be reused or recycled is not considered as a major benefi t in the survey An interviewed environmental consultant pointed out that the WMP method can provide a draft list of materials to be reused or recycled before a project starts however it levels of reuse and recycling sometimes diff er between the pro posal and the actual practices of projects A contractor claimed that most of construction organizations try to min imize their waste in other ways including using prefabri cated building components and reducing the use of wet trades before reusing or recycling the construction waste Therefore the fi nal waste generation can be greatly reduced 4 3 Diffi culties in implementing the WMP method Although many benefi ts can be gained in implement ing the WMP method there are still many construction organizations fi nding diffi culties in the implementation The major reason is high investment cost such as resource input for training courses Shen and Tam 2002 A study by Kuhre 1998 study showed that the support of the implementation of the method by top management was crucial at the early stage of the process A study by Tron 1995 considered that the lack of rel evant empirical experience on the method to support the development of a practical guideline was one of the main concerns for its implementation Other major diffi culties include lack of resources and expertise lack of staff involvement and poor co ordination between the government industryandbusiness ChanandLi 2001 Based on these previous studies nine major diffi culties are identifi ed and shown in Table 8 ranked by the relative importance index From the F statistics results Low fi nancial incentive is signifi cant The mean score of it for G4 governmental departments and developers is 5 00 which is higher than the overall average score of 4 11 indicating that govern ment departments and developers do consider low fi nan cial incentive in implementing the WMP method In the