Friday 6 February 2015

Construction Sector - practicing environment

Training opportunities can be scarce for some of our friends who are working in the construction sector. They may either be preoccupied in keeping up with work schedules or aren't able to attend training for some reasons. Well, here is a form of summary that may be useful to address environmental concerns on the job. This article approaches the norms in constructions activities from the environmental perspective. It is solely based on the author's close proximity with the construction activities in terms of site audits, EMS ISO14001 assistance and on-site trainings rendered since 2003. This discussion represents environmental repercussion and effects incurred by many construction companies. These issues are, however, truly under the aegis of project proponents, developers or landowners. Environmental consideration in project design, planning and execution is indeed in their hands. Construction companies builds them according to the desired specifications. I may have left some points behind, so, you're welcome to remind below and share for others to benefit.


INTRODUCTION
Construction activities, including demolition and reconstruction are engineering practices which inevitably causes environmental impact. The existing geophysical on-site environment are affected from its land-clearing until project hand-over and extended further during its occupation, utilization and abandonment. Conflicts of land uses are also prime factors which affects existing human habitat and environmental systems.
Apart from the site's environmental elements which are being modified and transformed, building materials from external resources are being brought in as construction materials. In fact, materials from the natural resources are extracted to meet its specified demands. "Around half of all non-renewable resources mankind consumes are used in construction, making it one of the least sustainable industries in the world."(1) Thus an array of linked network of environmental aspects and impacts are interacting from various resources up to the site. It also appears to the author that 'green designs or green homes' projects aren't impeccably 'green' in environmental terms. So, in view of this realm while not precluding other human activities, obligates earnest environmental due-diligence in practice. 
EIA to EMP
The Environmental Impact Assessment (EIA) report contains important prediction of the probable environmental impact and their mitigating measures respectively. Are they au fait? "As a participant in the construction and development process, the success may depend on how well the environmental risks are identified, analysed and managed. Simply being oblivious of the environmental obligations does not relieve one of their liabilities."(2)
The subsequent obligation is to convert and transfer all related mitigating measures into practice. This is done by identifying what are recommended in the EIA and classify them based on project phases. By doing so a concise Environmental Management Program/Plan (EMP) can be developed concurrently. In short, this may be executed in the following steps;
  1. identify predicted environmental impact based on construction phases from the EIA report;
  2. identify recommended mitigating measures from the EIA report;
  3. obtain terms and conditions of EIA approval from the authority which approves the project (if any);
  4. study and identify these terms and conditions of approval from the authority by comparing them with the mitigating measures in (3) above;
  5. if steps (3) and (4) are identical, proceed to step (6) or, if they are complementing - add them on in step (6); and list them in order of 'priorities' by phase sequence;
  6. construct a comprehensive EMP according to the various construction phases by inserting what has been identified and understood in step (5) above; specific operational procedures (SOP) for delicate tasks or machines are usually recommended to be linked to each EMP steps;
  7. review and finalize the EMP with the respective Project Directors, Managers and Construction Managers in the presence of the Project Proponent;
  8. cascade down the verified EMP with all concerned sub-contractors appointed for their respective job-scopes - preferably in their respective agreements or purchase-orders;
  9. incorporate this EMP as part of the legal register and internal audit standard accordingly.
  10. use the EMS philosophy by reviewing construction procedures of the affected construction phase for every non-conformance noted in the audit and deploy means to prevent its redundancy;
  11. ensure personnel's preparedness to perform and comply with the stipulated EIA-EMP requirement;
AIR POLLUTION
Air pollutant begins its entry in the environmental media of any project site the moment the first machine such as prime movers bulldozes into the sites' boundaries. Its noise, vibration and smoke emissions from its diesel combustion engine marks the initial air pollution impact. Public complaints of dust fall-outs are more prominent in projects involving hill tops. Entry routes into construction sites which may involve transboundary issues and hill slopes cuttings to raised project sites are some exemplary contradictions and conflicts of land-use. Specialized management tools which addresses potential issues of conflicts are needed much earlier in the project planning stages, not during construction. Despite these efforts air pollution is still vivid as the construction first phase is executed. The following elements usually helps construction companies control, if not minimize air pollution effect from their activities;
  • identify geological information about sites' topography, vegetation, rock and soil types - they release varying properties of dust into the air;
  • identify meteorological wind patterns and strength affecting the construction area especially in addressing vehicles' movements, hill cutting works, boulder or rock blastings and other activities which agitates dust into the air;
  • identify environmental recipients especially 'environmental sensitive receptors' within adequate radial distance from access routes and project site (based on the above data);
  • identify how our construction activities subscribe to the local environmental law, in Malaysia, namely Environmental Quality (Clean Air) Regulations 2014; and the Diesel Engine Emission regulations, etc.
  • identify mitigating measures described and stipulated in the EIA approvals' 'terms and conditions' and verify its adequacy on-site
In some instances environmental mitigation measures were found to be lacking after projects were already awarded and underway. In many instances, construction companies had undertook those additional liability! This is especially common after these sites receives legal inspection and directives by the authorities or their representatives. Well, in reality, project proponents aren't holding much hands-on liability under conventional contracting laws. Judiciary practices for such matters may not be conducive enough. So, this should be addressed prior contractual-bidding! As gathered from practice, the following areas are common issues not well addressed in project contractual TOR (Terms of Reference) between developers and construction companies in relation to Air Pollution;
  • additional directive from local environmental enforcement agency: In one on-site example, a construction company was requested to raise its tarpaulin barricade to several more feet in height and conduct additional ambient air monitoring on fugitive dust emission around the area.
    The open sand-blasting area was apparently an ad-hoc fabrication of some of its customized metal structures. A tossed-off sub-work undertaken to please its customer. Additional material and man-hours are incurred as additional costs to raise and extend the barricade including several days of dust particulate monitoring.
  • air pollution control equipment; Construction companies have received impromptu directives to install control measures especially involving projects which are not subjected to EIA requirements. An example is in the control of noise which affects adjacent dwellers. Pneumatic drillers, rock borers, loading-unloading construction materials etc., are loud or annoying enough to degrade aesthetic qualities of its surrounding habitat, especially that of human. In one case, the construction company was given a limited 'working time' and 'less intensity of work' for such activities which resulted in slight overdue in their work schedule. Noise is a stress for their neighbours as much as lost time is a stress for the company.
  • environmental air monitoring; Some construction companies overlooked several tiny details of this requirement and ended up in an increased spending. One classic example involving air pollution aspect is the HVS (High Volume Sampling) ambient air monitoring. Out of either knowledge-less or care-less they conducted 15 stations for HVS for parameters TSP (Total Suspended Particulates) and
    PM10 (Particulate Matters smaller than 10 microns), whereby, only 2 of those stations were about 700m upwind and nearest from a small residential village, a direct environmental receptor. The remainder of HVS stations are bordering jungles, streams and a waterfall. Well, if the company is not interested or involved in studies on eco-bio-receptors or zoo-receptors, I think this is simply overwhelming. I'd love to learn how the legendary Malaya Tigers react to inhaling particles sizing less than 10 microns. A small cough or a snare? So, thorough understanding on what is required and how to apply them is predominant. 
  • environmental training; In many cases, the main contractor would include this in their bid for the project. And, in as many cases too they hire sub-contractors to do their hands-on activities.
    So, all the engineering and construction personnel of the main contractors are knowledgeable of their environmental responsibilities. Later it was learnt that the main contractor received several compounding of offences from the authority for two spots of illegal open burning of used form-works and a spillage evidence of spent lube oil from their gen-set. Both offences were committed by their sub-contractors. So, those in-house training was not well cascaded down the hierarchy. These offences costed RM6,000 from their margin, in this case. Apparently, some big-timer, family owned, or traditional-for-generations business empire 'sub-contractors' prefers to do it their 'own' way of the 'green practice'. They need to catch up with today's globalized construction practices which emphasizes human and environmental values if they wish to sustain or expand the empire. Huge banks are today financing big projects with environmental consideration. "Large infrastructure and industrial Projects can have adverse impacts on people and on the environment."(3) 
  • environmental competent persons; So far, there's no real issue with regards to the requirement of air pollution control equipment competent person in the local construction scenario.
    Unless, the construction site has a quarry or stone crushers, premix or asphalt plants operations within its area, then, these vendors or suppliers are subjected to air pollution control techniques and its associated laws. As such, the dust collector or filter baghouse operation in asphalt or premix cement hoppers and silos installed in the construction site are regulated. Thus, the operation of such systems require a fulltime competent persons certified for the particular types of air pollution control equipment.
Well, still the lowest cost which offers more value-added items and versatility appears more attractive to project owners, regardless of whether it had solicited through the BAFO, bonus system or the swiss challenge. This dilemma can be addressed at the highest level of policy makers of a governance. The national environmental policies and their 'upbringing'. They should inculcate what the International Finance Corporation under the World Bank Group has published in their document titled  "Performance Standards on Environmental and Social Sustainability" in January 1, 2012, which describes their commitments, roles, and responsibilities related to environmental and social sustainability.

Construction equipment which contributes to air pollution are

  • heavy machineries which are diesel fuel powered such as the prime-movers, bulldozers, excavators, etc.;
  • lorries and other loading vehicles;
  • power generation equipments such as the diesel-fuel powered gen-sets;
  • common equipments like bar-benders, metal cutters, etc.;
NOISE AND VIBRATION
Noise is generally any unwanted or undesirable sound to human. It is rather relative as the author is personally interrupted with sounds of water dripping from a leaking tap as he writes this article in a quiet environment. On the contrary and in rare occasion, he would bear listening to the classic 'stairway to heaven' at almost full volume. So, its magnitude or intensity coupled with exposure duration and frequency, and individual tolerance coupled with background ambience may constitute a better picture to define what is noise and sound. The author respectfully surrender this to the related experts to publish and share more enlightening facts.  The construction sector is stereotyped with noise generation from almost all their activities. It originates from both human and machine factors involved throughout the construction's hustle and bustle. It is for this banality that prompted the Department of Environment Malaysia to initiate its publication of noise management guidance for the sector. "The Department of Environment hereby published 3 sets of documents to provide guidance on acceptable noise limits for various types of land use and human activities. The Planning Guidelines for Environmental Noise Limits and Control provide noise acceptance criteria for quantitative assessment of noise to define disturbance or otherwise. The Guidelines for Noise Labeling and Emission Limits of Outdoor Sources prescribes comprehensive methodology to measure and report noise emission from outdoor sources. The Planning Guidelines for Vibration Limits and Control gives vibration acceptance criteria for quantitative assessment of vibration."(9).  Apparently noise monitoring is a requisite in most construction works to justify its levels are meeting; 


  • EIA terms and conditions of approval;
  • EIA recommendations in its mitigation;
  • terms and conditions stipulated in any general approval related to the project; such as approval to its initial proposal or construction proposal, etc.;
  • impromptu directives from relevant authorities;
How should noise monitoring be carried out? The following summary gathered from experience could be a representative overview;
What is the type of site? (geology and meteorology) What are the noise level parameters? What is the size of site? What are the major sources of noise? What is the loudest and longest in use equipment? What are the environmental receptors? What is the criterion in selecting monitoring points from the noise mapping contour?
  • Who are the interested parties prompting the monitoring? - authority or residential neighbours or NGO, political personnel or proponent or mass media, etc;
  • Where is the construction site versus where are the environmental receptors and interested parties? Where are the noise monitoring stations? Where to start first?
  • When to begin monitoring work and when to end it? When to start and finish each monitoring activity for each monitoring point?
  • How to select noise monitoring stations or points? How to establish the noise mapping contour? How to select most representative noise monitoring points after the contour? How much noise is permitted (permitted levels)? How to report and present these data? How to interpret them?
  • Why are we doing this? 
Therefore, noise level data should serve its purpose when it has been performed for the purpose. Construction companies should compile them in a manner that these information can be used as reference in future project plannings. They should be tabulated in a comparative scale for various geophysics of construction sites.

Vibration is another concern in environmental sciences of the construction activity. "Vibration consists of oscillatory movements of particles (molecules) around their equilibrium is a solid body, liquid or gas, in the area of infrasound (less than 20 Hz), and partially also in the audible sound frequency range (up to 1500 Hz)".(10) The magnitude and intensity of vibration from any construction sector are influenced by the following;
  • rigidity of surfaces when in contact with objects of great forces; By virtue that compact solid solid surfaces means less air pores in its packed molecular arrangement simply means they are good conductor for even the slightest and weakest force of impact.
  • energy of force that induces the vibration; such as machines' strengths and power used. For example, a moving excavator and the pneumatic-driller are both generating vibrations but the former has records of causing cracked walls on neighbouring residential concrete structures but not the latter. Thus, the frequency and strength of these vibrating forces that matters in terms of potential cause of environmental impact.
  • ergonomics?. Angle of force applied onto contact surfaces in the various elements of a construction is also a factor. Seemingly, its about quick versus unhurried jobs in a mass of rock, acres of soil surfaces and tonnes of construction materials. Unlike precision engineering of the watch making factory where the engineer leaves his work as clean as when he comes in the morning and deals with materials in their nanos and microns. Construction is bringing in, putting together, demolishing and refuse everything in tonnes. Its a tough Ergonomics. 
Vibration caused by stationary machines like the generator sets are easier to mitigate, where a suitable damper placed at the correct points of contact could absorb its vibration issues. Most other construction activities, however, involves an array of tasks, tools and machines which are moving or unfixed. Excavators, backhoes, power machining tools etc. are always mobile which is impossible to manage them at those points of contact between vibrating forces and rigid surfaces. Here is where the challenge is for construction engineers. We are not talking about building structures that withstands earthquake of typhoons, but, we are merely discussing the basic construction practices. And, not to cause 'typhoon or earthquake' -like effects to our neighbours.


WATER POLLUTION
Activities in construction sites can pollute various water bodies, namely inland waters; such as rivers and aquifers or marine waters which include estuarine. The majority of severe cases gathered so far infers to one most common polluters of water that is Suspended Solids.
Primarily, suspended solids are loosed soil particles or debris which are being swept away as surface runoff from bare land surfaces and flows gravitationally to lower lying areas and eventually into the respective water bodies. It causes mud floods, mud slides or flash floods along its way. The aftermath is probably not only clean up but also compensation expenses. Conventionally, most construction companies engineered a mitigation for such erosion and sediment transport effect by means of a retention pond. Its size varies in a calculated proportion of a few main factors such as area of open land, slope gradient, maximum rate of rainfall recorded, hydraulic loadings and type of soil etc. The overflow water from these ponds are often subjected to a certain arbitrary discharged standards by the authorities. In most cases, environmental parameter of concern is the suspended solids, but in some others this requirement includes biological and chemical oxygen demands (BOD and COD respectively). Usually the main construction company are required to liaise directly with the authorities. Other types of pollutants includes oil spills and slicks, solvents, oil-water mixtures, solid wooden debris and other solid wastes.
Fuel, especially diesel is a constant need for major machineries in construction activities. So, these fuels are stored in bulk storage tanks of various sizes. In a few remote cases, an industrial grade fuel tank ruptured and spilled out its oily content into a ditch and inundated a small river nearby which eventually flowed into a coastal area. In addition, there were such incidents involving medium fuel oil, light fuel oil, diesel fuel, cleaning solvents contaminated with paints and even acid and other chemicals commonly used in construction works. 
Such spillage usually cause accumulative and connective effects to the qualities of the receiving water bodies, aquatic lives and various trophic levels and food chains of the ecosystem. "Freshwater environmental impacts can be more severe because water movement is minimized in these habitats. In standing water bodies, oil tends to pool and can remain in the environment for long periods of time. In flowing streams and rivers, oil tends to collect on plants and grasses growing on the banks. Oil can also interact with the sediment at the bottom of the freshwater bodies, affecting organisms that live in or feed off of sediments"(4)

Thus, some lessons learnt from this and other accidental releases inferred the need for a proper secondary containment when storing oil and other liquid chemicals. Apparently there are some published guidelines about how these secondary containment should be like. These references are noteworthy and handy. Nonetheless, safety is always first and do construct them with plenty of common sense! 

As gathered from practice, the following areas are common issues not well addressed in project contractual TOR (Terms of Reference) between developers and construction companies in relation to Water Pollution;
  • additional directive from local environmental enforcement agency: In an example, a construction company as in many of its previous practises had installed a wash-trough and manually operated water-jet spraying to clean their lorries before they enter public roads. 
    In one 'spot-check' a sample of overflow wash water from this wash trough was taken by the authority and from their laboratory analysis was found to contain about 20 - 50 mg/L of Oil and Grease. They also photographed observations of its releases which flows into a nearby public ditch. About a month later the construction company received a legal directive to install a filtration system to ensure that the concentration of oil and grease and suspended solids discharged from the area complies to limits stipulated under Environmental Quality (Industrial Effluent) Regulations 2009 before entering into the nearby public ditch or drain. The premise belongs to the project or developer or land-owner. (For details of this regulation, kindly link to: http://sekitarsynergy.blogspot.com/p/iets-law.html) 
    The construction activity is primarily a liability of the main contractor. The wash trough, the lorries and washing workers were contracted out to one of their sub-contractors. However, the authority was keen to dart their directive towards the main contractor only. Hastily, the company cleaved to it and installed a physical separation system which consists of a smart integration of oil interceptor and grit chamber. And, at their expense as it wasn't listed in their awarded project's TOR. Later, they managed to convince their subcontractor to conceive of the responsibility to partially reimburse some cost, fully finance its maintenance and liable to all its legal risk. This kind of unexpected liability can be avoided with sound project TOR right from the top of the project planning and awarding contracts.
  • water pollution control equipment; Apart from the above example, there are several major projects that employs large number of construction workers.
    Some are provided with modest hut-type wooden squatter houses while others are housed in well constructed living quarters. These shaggy squatters are usually not equipped with hygienic sanitary facility and their domestic wastes are poorly managed. 
    The later are usually provided with decent toilet cabins which are connected to a set of imhoff tanks as its sewage treatment system. As such, sewage is the point source of water pollution in this area where the local law Environmental Quality (Sewage) Regulations 2009 regulates permissible levels of its water pollutant parameters. Installation, maintenance and repairs of these auxiliary facilities are cost worthy to be considered to ensure its continuous usability.
  • environmental water monitoring;  Today, it is a legal binding requisite for construction companies to perform various environmental water quality monitoring work at their construction sites. The overflow discharges from retention ponds, wash troughs and also sanitation facilities are some common sources which subscribes to such requirements. Apart from these samplings at source, the ambient monitoring of related environmental receptors aimed at gauging consequential impact is also a norm. As an example, for constructions site situated adjacent to rivers, lakes, water catchment areas or coastal areas, they are required to perform water quality monitoring for certain parameters of interest. In many instances, upstream and downstream points along the predicted plume of pollutant dynamics or movement are required in these ambient samplings.
    Affected construction companies would usually outsource competent environmental contractors to perform these samplings and analysis. The number of sampling points, accessibility to sampling sites, number and type of environmental parameters, legibility of sampling and monitoring equipments, credibility of personnel and laboratories, frequency and period of these specialized function are factors to consider in meeting the EIA and legal requirement. They must be well anticipated and constituted in construction scheduling and costing as well. 
  • environmental training; Unless constructions companies have a number of experienced public speakers cum experienced construction personnel to perform engaging in-house training for their staff, it's still worthy to outsource this function for a wider scope of shared experience and knowledge.
    In addition, construction personnel should be encouraged to undergo public training courses and undertake external audit jobs or multi-site audit as means to foster capacity building of own human capital. Hence, these emerging experienced personnel, by then, may in turn provide their version of training on identical if not expanded in-depth environmental topics for newer staffs. This must go on and on towards better, smarter, self-reliant, and more productive environmental human capital resource.
  • environmental competent persons;
    The operation of sewage treatment system is subjected to such competency requirement according to the Environmental Quality (Sewage) Regulations 2009. The following is a summary of this regulations; 
  • Written notification for new source (upgrade existing – nil);
  • No requirement for Professional Engineer’s undertaking;
  • To operate and maintain – sound engineering practice;
  • Parameters: specific to sewage characters i.e. not shared with industrial effluent;
  • COD inclusive – varies according to sewage treatment type for existing;
  • Full-time competent person – trained and certified by DOE;
  • Performance monitoring report is required based on legal format;
  • Best management practices requirement not regulated;
  • By-pass is prohibited – dilution ‘law is silent’;
  • Spills, accidental release or leakage – 6 hours to DOE;
  • No provision for Prohibition order by DOE for continued incompliance;
  • Direct judicial action under the regulation enabled;
  • Disposal of sludge into inland and marine waters not allowed;
  • Disposal of sludge onto land/soil – Written Permission DG DOE. 
Therefore, it is wise to send some civil engineers and other construction personnel to acquire such competencies. Contracting out by hiring external competent persons may not only be uneconomic in long term but pose a risk in its legal aspect. Please check with the law book and the authority in prior. In the context of environmental parameters, please take note of parameters such as Ammoniacal Nitrogen and Nitrates. These elements are primarily inferred as final products of the protein breakdown, typically, from human excretory or faecal wastes. They are indeed components of the natural nitrogen cycles. But, when their proportion are imbalanced, due to excess entry into the ecosystem, which in simple terms; when one component enters in quantities that is too much for 'on-time' assimilation for the cycle to work normally, this surged load causes subsequent impacts in the water body. There are various sources of ammonia in rivers as follows:- (8)
  • fertilizers for land and agricultural developments.
  • uncontrolled landfill leachate and land development.
  • untreated sewage from poultry farms, reverine squatters, septic tanks, factories, makeshift and toilets at construction sites.
  • wastewater discharges from domestic, commercial, institutional and similar facilities.
  • wastewater and toxic chemicals discharges from different types of industries
  • surface runoff and washouts resulting from rainfall
  • oil, sullage (wastewater) from bathrooms and kitchens
  • municipal sewage treatment plant effluent
However, excess use of detergents and fertilizers have also contributed to its persistence in natural water bodies. They are significant in the environmental sciences because of their potential to cause a condition known as eutrophication - a kind of water pollution which is toxic to aquatic life thus the human food. 
HAZARDOUS WASTES
Hazardous waste are materials which pose detrimental effects if not managed accordingly by virtue of not understanding its hazard potentials. Like any working areas they may also pose potential hazard and potential risks. Therefore, acquire their material origin's MSDS and read to understand them first! In other words; know them then manage them. Most hazardous waste are prescribed and listed in the Environmental Quality (Scheduled Wastes) Regulations 2005. Scheduled wastes (SW) commonly found in most construction activities are;
SW 102            Waste of lead acid batteries in whole or crushed form
SW 103            Waste of batteries containing cadmium and nickel or mercury or lithium
SW 110            Waste from electrical and electronic assemblies containing components such as                                    accumulators, mercury-switches, glass from cathode-ray tubes and other activated                                glass or polychlorinated biphenyl-capacitors, or contaminated with cadmium, mercury,                            lead, nickel, chromium, copper, lithium, silver, manganese or polychlorinated biphenyl.
SW 206            Spent inorganic acids
SW 303            Adhesive or glue waste containing organic solvents excluding solid polymeric materials
SW 305            Spent lubricating oil
SW 306            Spent hydraulic oil
SW 307            Spent mineral oil-water emulsion
SW 308            Oil tanker sludges
SW 310            Sludge from mineral oil storage tank
SW 311            Waste oil or oily sludge
SW 312            Oily residue from automotive workshop, service station, oil or grease interceptor
SW 325            Uncured resin waste containing organic solvents or heavy metals including epoxy resin  and phenolic resin.
SW 327            Waste of thermal fluids (heat transfer) such as ethylene glycol
SW 408            Contaminated soil, debris or matter resulting from cleaning-up of a spill of chemical,                                mineral oil or scheduled wastes
SW 409            Disposed containers, bags or equipment contaminated with chemicals, pesticides,  mineral oil or scheduled wastes.
SW 410            Rags, plastics, papers or filters contaminated with scheduled wastes.
SW 416            Sludges of inks, paints, pigments, lacquer, dye or varnish
SW 417            Waste of inks, paints, pigments, lacquer, dye or varnish
SW 418            Discarded or off-specification inks, paints, pigments, lacquer, dye or varnish products  containing organic solvent
SW 421            A mixture of scheduled wastes
SW 422            A mixture of scheduled and non-scheduled wastes
SW 425            Wastes from the production, formulation, trade or use of pesticides, herbicides or  biocides
SW 426            Off-specification products from the production, formulation, trade or use of pesticides,  herbicides or biocides
SW 429            Chemicals that are discarded or off-specification
However, the variety and quantity of SW do vary with the nature of construction activity. For instance, the tunnel boring for underground transport system encounters different environmental issues as compared to building hilltop residences. In the overall perspective, they are still similar if not identical types of SW being generated by common machines.

GEOLOGICAL DISRUPTION
We built this city on rock and roll. We pile the bedrock and roll fibre mats on slopes haven't we? The following activities are altering if not upsetting the already unstable rock formation underneath us; 


  • bore piling; drilling; blasting; tunnel boring; hill cutting; and others.

So, these 'natural' structures such as hills, mountains and bedrock have their own purpose. They store natural resources and stabilize the earth surfaces that we live on. The 'birds-eye' view is often spectacular. So, we build exclusive dream houses on hill tops or even slopes. Engineering are sciences for the thinking people who are always finding methods in making dreams come true. Our wishes are their command. They literally have to bout with natural forces and phenomena. They are the go-getters and daredevils of our physical nature. Well, they win some and lose some. They win in the expense of nature and they lose when nature reacts. The construction on slopes for instance is not done with just a flick of the engineers' fingers.
They have studied them by employing geologists who 'turns stones to bread' from their specializations. In other words, they know what they are dealing with. One of the primary geologic factors that contribute to mass wasting is the steepness of slope (topography,) generally the steeper the slope the more likely it is to fail.(5) In another construction's feat with nature is the tunnel boring activity. Mass of the earth's mesosphere are bored through in this infrastructure construction. The use of TBM enables the realization of such treacherous endeavour which pose different kind of challenge to engineers and the environment. Their desire is to build tunnels for underground public transport, underground highways, sewage or even flood control cum highways like the KL's SMART tunnel are realized through hard thinking, sweat, blood, perseverance and probably carpal tunnel syndrome. Their tenacity is unbelievable although their gallantry remains unsung.
All these are in response to cater for new demands in human civilization, usually, in the expense of the environment, thus, in this instance - the ground rock structures. Structures which happens to be the strongest natural 'civil engineering' by far that secure earth surfaces on its plates. Engineers are ingenious when at work. They not only find ways, but, solve problems which constantly emerges along their ways, relentlessly. In preventing sinkholes, for example, they grout the fractures. And, they have a handful of options to do this and it worked in engineering terms. In the Kuala Lumpur's Sungei Buluh - Kajang (SBK) line, an amazing challenge awaits tunnel borers.
They need to bore through two different geological rock formations; the Kenny Hills' cohesive and plastic type and the KL karstic limestones. Typically but amazingly they opted to yet another ingenious 'way' to do it - Variable Density TBM. The ‘variable density’ enhancement that led to this technological innovation is the first of its kind in the world.(6) They do encounter those various forms and symptoms of geological stresses, and, still mitigate using the conventional grouting method, but, with deeper engineering repertoire of surmounting results. While in some other parts of the world where grouting activities have mostly relied on artificial materials including those of petrochemical origin which poses buried hazard to the ecosystem, the SBK-Line have smarter and greener brains. Conventionally, "The ingredients for the preparation of mortars and grouting suspensions include: cements, bentonite, clay, sand and fillers, additives for stability and water. For sealing much precious fissured zones or small karst conduits, recommends the following materials and technologies: grouting using different types of cement mortar with additives and fillings (sand, gravel, chemicals, etc.); polyurethane foam grouting or grouting with asphalt or hot bitumen."(7) This SBK-Line, however, reuse bored materials by installing an adjacent on-site treatment of mud slurry which 'treat' it into its higher density forms for use as grouting media. (This fact is jaw-dropping but do correct me if I understood it wrongly). If I'm the premier, I'd probably have at least nominate them for the prestigious Hibiscus Award and text their experience in local engineering book! The Malaysian experience. 
It's about resource conservation through state-of-the art recycling!At this very point too, I'd implore that they go on a bit more.
I sincerely hope that the excess slurry (if any) be converted into 'brick-pavers' for use in this project as well. So, they could proudly name them the 'SBK-paver'. No, the company don't need any high-tech costly techno for this. This site have all its constituents already. Its just a matter of getting them together in the right proportion. As a tip, one may pragmatize the local 'Labu Sayong' village producers in Kuala Kangsar. Then, you'll see what I meant. Scheduled Wastes? Kindly pose a ponder to the agency by conveying my warmest regards to them and politely ask: "Recycling or Landfill Leachate? - Resource Conservation or No More Land for Landfills?" I believe the agency have worked so hard and gathered so much experience all these years and acquired much enough wisdom to differentiate the two sides of a coin. When they do, ask further: "The Law Books or Environmental Management?" Further checks beyond this point is surpassing my comprehension. Sorry, and with all due submission to the local convention and constitution.

BASIC BMPs IN CONSTRUCTION ACTIVITIES
With special reference to the Erosion and Sedimentation Control is the following summary for Effective Storm-water Site Plan in practice;
1.Minimize Clearing and Grading; Construction site operators should take all measures possible to avoid clearing/grading stream buffers; forest conservation areas; wetlands, springs and seeps; highly erodible soils; steep slopes; environmental features; and storm water infiltration areas. In addition, site fingerprinting (impact indicators) should be employed and limits of disturbance (LOD) should be mapped, clearly delineated on site with flags and conveyed to personnel. 
2.Protect Waterways; Construction site operators should identify water-bodies on site and adjacent to the site. If construction activities occur near a water-body, clearing/grading activities should be minimal and silt fencing and/or and earthen dikes should be installed
3.Phase Construction to Limit Soil Exposure;Prior to construction initiation, activities should be broken into stages or phasesGrading activities should be limited to the phase immediately under construction to decrease the time that soil is exposed, which, in turn, decreases the potential for erosion.
ü Additional phases should begin only when the last phase is near completion and preferably exposed soil has been stabilized.
ü Construction scheduling should facilitate installation of erosion and sediment control measures prior to construction start, detail time limits for soil stabilization after grading occurs, and schedule BMP maintenance.
4.Immediately Stabilize Exposed Soils; 
Exposed soils should be stabilized within two weeks of the onset of exposure. The long-term goal is to establish permanent vegetation after each phase of construction; however, mulching, hydroseeding, or other means of soil coverage may protect exposed soil while facilitating vegetation growth. The storm-water site plan should detail appropriate plant species to be seeded, as well as weather and climatic conditions necessary for germination and successful vegetation establishment.
5.Protect Steep Slopes and Cuts; Cutting and grading of steep slopes (>15 percent) should be avoided wherever possible.


If a steep slope exists, all water flowing onto the slope should be redirected with diversions or a slope drain. Silt fence at top and toe of the slope must be anchored well, although this measure may not provide adequate protection by itself. On steep slopes, padi-straw netting and erosion control blankets (geotextiles) should be used in conjunction with seeding or mulching, as seeding alone may not be effective.


6.Install Perimeter Controls to Filter Sediments; Silt fence should be properly installed around the perimeter of the construction site. A fiber roll on the inside (site-facing) of the silt fence works to provide additional filtration. In areas of heavy flows or breech concern, a properly sized earthen dike with a stabilized outlet should be created. In addition, catch basin inlets receiving storm-water flows from the construction site must be protected with adequate inlet controls
7.Employ Advanced Sediment Settling Controls; Sediment Basins should be created where space is available; however, discharge from basins must be non-turbid. The use of skimmers and multiple cell construction of basins assist in sediment drop-out.
8.Certify and Train Contractors on Storm-water Site Plan implementation; Contractors and/or construction staff should be trained in erosion and sediment control practices and procedures to effectively install and manage erosion and sediment control features. Meetings and site inspections by municipal staff provide opportunities for discussion of effective BMPs with site staff. Inspectors should make a strong commitment to contractor education to develop a constructive and responsive relationship.
9.Control Waste at the Construction Site; The site plan should describe the type of construction site waste found at the site (such as discarded building materials, concrete truck washout, chemicals, litter, and sanitary waste) and how that waste will be controlled to minimize adverse impacts to water quality. For example, concrete washout and trash storage areas should be clearly labeled on the plan and should be located away from water-bodies and catch basin inlets.

10.Inspect and Maintain BMPs. Each storm-water site plan should clearly describe the construction site operator's BMP inspection and maintenance, including who will inspect the site and how often. Ideally, an example inspection form should be included with the plan. Inspections should occur at a regular interval and should also occur immediately before and after rain events. The plan should also describe how BMPs will be maintained.

Thus, construction is building human civilization. It has been done since day-1 of man on this planet. Civilization has been built and lost. Some was down in rubble and humbled under our feet, while others were sunk like the legendary atlantis. We are never correct as there's always correction. Do what we need and seek HIS forgiveness.





Thank you for the attention.
Khalid Mohd Ariff
E-mail: sekitar5221@gmail.com
16th Rabi'ul Akhir 1436 @ February 7, 2015

REFERENCES (with many thanks and appreciation)
  1. http://www.willmottdixongroup.co.uk/assets/b/r/briefing-note-33-impacts-of-construction-2.pdf
  2. Environmental Impact Assessment (EIA) and Construction by Amit Bijon Dutta1 and Ipshita Sengupta, International Research Journal of Environment Sciences, Vol. 3(1), 58-61, January (2014) www.isca.in, www.isca.me
  3. THE EQUATOR PRINCIPLES, JUNE 2013, A financial industry benchmark for determining, assessing, and managing environmental and social risk in projects, www.equator-principles.com
  4. http://www.epa.gov/oem/docs/oil/edu/oilspill_book/chap1.pdf
  5. http://www.nature.nps.gov/geology/hazards/mass_wasting.cfm
  6. http://mymrt-underground.com.my/tunnelling-information/tunnel-boringmachines/
  7. Ognjen Bonacci,1* Sanja Gottstein2 and Tanja Roje-Bonacci1, "Negative impacts of grouting on the underground karst environment", ECOHYDROLOGY Ecohydrol. 2, (2009) page 493.
  8. http://www.iwk.com.my/v/knowledge-arena/ammonia
  9. www.gunungganang.com.my
  10. http://ro.uow.edu.au/cgi/viewcontent.cgi?article=3381&context=hbspapers









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