The Q1 earnings season is going full throttle with over 180 companies on the S&P 500 index reporting this week. Taking into consideration the 132 companies that have reported results till Friday (Apr 22), the earnings trend has more or less confirmed the grim projections for the quarter. Based on the hitherto declared results, Q1 is widely expected to be the fourth consecutive quarter to suffer an earnings decline for the benchmark index.Plagued by a plethora of macroeconomic issues and continued volatility in the equity market, Q1 earnings estimates for the S&P 500 index have gone downhill over the last three months, albeit improving slightly in the last few days. Per the latest Earnings Trend Report, overall Q1 earnings for the S&P 500 companies are expected to be down 9.4% on a 0.8% decline in revenues. Guidance for most companies that have reported so far was lowered to easy-to-beat levels, resulting in better-than-expected earnings and revenues.However, the overall Q1 earnings scenario still remains clouded with uncertainty. What is more alarming is that the likely dismal earnings performance is not attributable to the inherent weakness of the Energy sector alone. Rather, downward estimate revisions are expected in almost all the sectors, barring a few. About 9 of the 16 sectors are expected to witness an earnings decline in the quarter under review, with Oil/Energy, Basic Materials, Industrial Products, Aerospace, and Conglomerates being the most notable.Among the waste management stocks slated to report this week, let’s have a sneak peek at three major players to see how things are shaping up for the upcoming quarterly results.Republic Services, Inc. RSG will report first-quarter 2016 results before the closing bell on Apr 28. Increasing customer engagement on the digital platform may act as a growth catalyst for the first quarter. During the quarter, the company launched “click-to-buy capabilities” for approximately 50% of residential subscription markets. Given the evolving needs of the customers’ buying preferences, Republic Services expects solid market traction for its latest offering, which in turn will likely be conducive to growth. For the impending quarter, Republic Services has an Earnings ESP of 0.00% with a Zacks Rank #2 (Buy) (read more: Republic Services Q1 Earnings: A Surprise in Store?).Waste Management, Inc. WM is scheduled to report first-quarter 2016 results before the opening bell on Apr 28. During the quarter, Waste Management completed the acquisition of some business assets in Florida from regional waste management firms, Southern Waste Systems and Sun Recycling, which are likely to be accretive to earnings. The transaction is a strategic fit for the company and is in sync with its existing operations and service offerings. At the same time, the takeover enables Waste Management to extend its geographic footprint and foray into the lucrative South Florida market. A steady stream of accretive acquisitions is likely to drive earnings for this Zacks Rank #2 stock (read more: Is Waste Management Set for a Beat in Q1 Earnings?).Stericycle, Inc. SRCL will report first-quarter 2016 results before the closing bell on Apr 28. Stericycle had earlier acquired the information destruction services provider Shred-it International. With Shred-it on board, Stericycle enhanced its core compliance solutions portfolio and began offering specialized services, thereby augmenting its value proposition to clients. These efforts are likely to improve its profitability in the first quarter as well. For the soon-to-be-reported quarter, Stericycle has an Earnings ESP of +1.74% with a Zacks Rank #4 (Sell) (read more: Will Stericycle Disappoint in Q1 Earnings?).Stay tuned! Check later on our full write-up on earnings releases of these stocks.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report WASTE MGMT-NEW (WM): Free Stock Analysis Report STERICYCLE INC (SRCL): Free Stock Analysis Report REPUBLIC SVCS (RSG): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research